Flight Simulation

Year in Review

FY97

Aeronautical Test and Simulation Division 1

Foreword

Aeronautical Test and Simulation

Division

NASA/Ames Research Center

Moffett Field, California 94035

29 December1997

This document is the Fiscal Year

1997 Annual Performance Summary of

the NASA-Ames Vertical Motion

Simulation (VMS) Complex and the

Crew Vehicle Systems Research

Facility (CVSRF). It is intended to

report to our customers and management on the more significant events of

FY97. What follows are an Executive

Summary with comments on future

plans, the FY97 Schedule, a projection

of simulations to be performed in FY98,

performance summaries that report on

the simulation investigations conducted

during the year, and a summary of

Simulation Technology Update Projects.
4 Aeronautical Test and Simulation Division

Acknowledgment

Special thanks to Tom Alderete, Matthew Blake, Girish Chachad, Ron Gerdes, Margaret Salas and

Barry Sullivan for contributions made to the production of this document.
Aeronautical Test and Simulation Division 5

Table of Contents

Foreword ............................................................................................................................... 3

Executive Summary ............................................................................................................ 6

FY97 Simulation Schedule .................................................................................................... 9

FY97 VMS Flight Simulation Project Summaries ................................................................ 10

FY97 CVSRF Flight Simulation Project Summaries ........................................................... 11

FY98 VMS Simulation Planned Project Schedule............................................................... 12

FY98 CVSRF Simulation Planned Project Schedule .......................................................... 13

Vertical Motion Simulator Research Facility .................................................................. 15

Variable Diameter Tiltrotor .............................................................................................. 16

High Speed Civil Transport 4 .......................................................................................... 17

The Technical Control Panel 1 ........................................................................................ 18

Space Shuttle Vehicle ..................................................................................................... 19

Comanche ...................................................................................................................... 20

Advanced Short Takeoff and Vertical Landing ................................................................ 21

The Technical Control Panel 2 ........................................................................................ 22

CH-53 Accident Investigation.......................................................................................... 23

Slung Load 4.................................................................................................................. 24

Space Shuttle Vehicle ..................................................................................................... 25

High Speed Civil Transport 5 .......................................................................................... 26

Partial Authority............................................................................................................... 27

Boeing-1 ......................................................................................................................... 28

Civil Tiltrotor's 20th Anniversary ...................................................................................... 29

Crew-Vehicle Systems Research Facility ....................................................................... 31

Tactical Decision-Making System ................................................................................... 32

Propulsion Controlled Aircraft 2 ...................................................................................... 33

Converging Approaches ................................................................................................. 34

TRACON-Flight Management System Trajectory Synthesis 2 ....................................... 35

Advanced Air Transportation Technologies Free Flight 2................................................ 36

Obstacle Free Zone Balked Landings ............................................................................ 37

Wide Area Augmentation System Bias Error .................................................................. 38

Aural Alerting .................................................................................................................. 39

Decision-Making ............................................................................................................. 40

Technology Upgrades....................................................................................................... 41

Transport Cab (TCAB) .................................................................................................... 41

Virtual Laboratory (VLAB) Demonstrator Project ............................................................ 42

Simulation Fidelity Requirements ................................................................................... 43

747-400 Visual System Upgrade .................................................................................... 44

Advanced Concepts Flight Simulator Upgrade Phase 3................................................. 45

List of Acronyms .................................................................................................................. 46

Appendix 1 .......................................................................................................................... 48
6 Aeronautical Test and Simulation Division

This Annual Report addresses the major simulation accomplishments of the Aeronautical Test and Simulation Division of the NASA Ames Research Center. The Ames Simulation Facilities operated by this Division

consist of the Crew-Vehicle Systems Research Facility (CVSRF) and the Vertical Motion Simulation Complex

(VMS). In addition to the continuing efforts to streamline and reduce facility operations costs at NASA, paramount to Division operations has been the continuing commitment to uncommon excellence in the development and production of efficient, real-time, high fidelity, safe, piloted flight simulations. The Division has also

continued to aggressively modernize in order to maintain reliability, our competitive edge and enhance our

responsiveness to users needs. The staff places very high value on customer relations and has successfully

provided highly responsive, cost-effective, value-added simulation support to all simulation customers.

The simulation laboratories, contained in two separate buildings at Ames Research Center, are part of the

Aeronautical Test and Simulation Division organization. The CVSRF comprises a Boeing 747-400 simulator,

the Advanced Concepts Flight Simulator (ACFS), and an Air Traffic Control (ATC) simulator. The VMS Complex comprises the Vertical Motion Simulator (VMS), five Interchangeable Cockpits (ICABs) and two fixedbase simulation labs. A brief description of these facilities follows this report in Appendix 1.

The purpose of this document is to briefly describe our accomplishments of the past year. Its outline

includes the Executive Summary, Simulation Schedule for FY97, Planned Projects for FY98, VMS Simulation

Projects, CVSRF Simulation Projects, and Technology Upgrades. The “Simulation Projects” sections state the

goal of each simulation and discusses high level results. Researchers and pilots from NASA and private

industry are identified as well as simulation engineers from the staff. The “Technology Upgrades” section

reports changes made, or in-process, in order to keep our simulation facilities state-of-the-art. Finally, a “List

of Acronyms” is included for the reader’s convenience.

Notable accomplishments for FY97 include:

There were 22 major simulation experiments conducted in the flight simulation laboratories in FY97. These

simulations reflect a continued concentration on NASA’s focused programs such as High Speed Research

(HSR), Advanced Subsonic Technology (AST), NASA’s Space Operations, and FAA/NASA Airspace Operations Systems. Support was also provided to other Government research issues with emphasis in Army

Rotorcraft and the Joint Strike Fighter (JSF) programs. In addition, there were several technology upgrade

projects either completed or with significant progress being accomplished during the year.

All simulation experiments conducted at Ames support significant research that is responsive to the needs

of the Nation with a focus on applied aeronautics research. Diversity, fidelity and breadth of simulation distinguish the research projects conducted at Ames as can be seen by reviewing the “Simulation Projects” sections of this report.

Technology upgrade projects for the past year include:

Within the CVSRF, a major upgrade to the capabilities of the Advanced Cockpit Flight Simulator was

completed this year. Host computers and Cockpit Graphics Systems were replaced by state-of-the-art systems which have substantially reduced operational cost with improved capabilities as well. The ACFS also

received a new advanced Vital VIII(i) image generation system with a 180 degree image presentation system

as part of the upgrade. Finally, the cab interior was completely reconfigured to better represent future commercial airliners. The 747-400 also received a new advanced Vital VIII(i) Image Generation Systems with a

180 degree Image Presentation System to complete its upgrade begun in FY96.

At the VMS, the new Transport Interchangeable Cab (TCAB) was completed this year and utilized in an

HSR simulation in August. This effort was in direct response to HSR and AST customer requirements for a

transport cockpit that better supported their future research needs.

The VMS developed a rapid response plan to replace an obsolete Computer Generated Image (CGI)

system used in the Vertical Motion Simulator. A 12 year old, 3-channel Evans & Sutherland(E&S) CT5-A was

replaced by a state-of-the art ESIG 4530 also built by E&S of Salt Lake City, UT. This was accomplished in an

innovative and cost effective manner by obtaining a surplus system from Johnson Space Center(JSC). In a

separate action, Ames is contracting for additional channels to bring the system to its full 8-channel capability.

When fully expanded, this new system will be used by both the High Speed Civil Transport and Civil Tiltrotor

programs in the new TCAB in the Ames Vertical Motion Simulator Complex.

The Virtual Laboratory, or VLAB, project was conceived this year and conducted a very successful demonstration with the June Space Shuttle Vehicle simulation at the Johnson Space Center. The VLAB project was

to develop a prototype that demonstrates the technology and methodology for remote access to a research
Aeronautical Test and Simulation Division 7

Executive Summary

facility employing an interactive, virtual reality interface. Although VLAB was prototyped in the VMS, the

concepts being developed have a much broader applicability - essentially to any remote access, virtual

control room situation, such as wind tunnels, flight test facilities, and multiple, interoperable labs.

Future Plans

All of the simulation facilities continue to be in high demand. There is a full list of projects for FY98 that

build on past research efforts and bring some new activities as well. We will continue our tradition of supporting mainstream NASA and national aeronautical development programs and being second to none in state-ofthe-art real-time simulation and enabling technologies. Automated tools for simulation and modeling, improvements in graphics and displays, and efficient computational environments are continuing efforts.

The new ESIG 4530 will be expanded to at least 5 channels and begin production operations by the 3rd Q.

of FY98

The VLAB activity began last year to make NASA simulation resources and research facilities more accessible, will continue. Using concepts such as Virtual Reality and other modern techniques, enhancements to

Virtual SimLab will be demonstrated. Next year will also see increased emphasis in interoperability between

Ames Facilities and outside customers.
8 Aeronautical Test and Simulation Division
 Oct ‘97

Simulation Operations BranchAeronautical Test and Simulation DivisionAmes Research Center FY97 Simulation Schedule

Simulation Facilities

Oct ‘96 Nov ‘96 Dec ‘96 Sept ‘97 Jan ‘97 Feb ‘97Mar ‘97Apr ‘97 May ‘96June ‘97 July ‘97 Aug ‘97

VMS

30 7 14 21 28 4 11 18 25 2 9 16 23 30 6 13 20 27 3 10 17 24 3 10 17 24 31 7 14 21 28 5 12 19 26 2

Shift A

9 16 23 30 7 14 21 28 4 11 18 25 1 8 15 22 29 6 13 20 27

I-Cab Fixed Base

Shift B

B747

ACFS

Shift A

Shift B

VDTR

NASASikorsky

HSCT

NASA/BoeingMcDD

SIMFR4

NASA-JSCRockwell

SSV SSV

NASAArmy

HSCT5

NASA/BoeingMcDD

PARTAUTH BOEING

ASTOVL

(BG)

SIMFR4 TTCP SIMFR 5 SSV Demo

NASA NASA

HSCT TTCP Comanche

ConvAppr

TRACONFMS Decision-Making AATT Free Flt OFZ Balked Lndgs WAAS Bias & OFZ PCA

FAA FAA NASA NASA FAA NASA NASA

AuralAlerting

Cert. OFZ Balked lndgs

NASA

Aeronautical Test and Simulation Division 9

MotionTuning

MotionTuning SIMFR4.5 TTCP

NASA NASA Lockheed NASA NASA

SLOAD 4 ASTOVL

NASA NASA-JSC

Rockwell

NASAArmy

NASABoeing

NASA

SSV Demo

NASABoeing McD

NASAArmy Army

ASTOVL

NASA

FAA Cert. Cert.

Facility Upgrade

TDMS ATC

Visual System Upgrade

NASA

FAA Cert.

NASA

NASA NASA

Army

SSV CH-53

IAF

TCABMotionTuning

TitlRotor Event Open

House

←

Boeing

NASABoeing
10 Aeronautical Test and Simulation Division

VMS Flight Simulation Projects

1. Variable Diameter Tiltrotor (VDTR)

Sept 9 - Oct 18 (VMS)

Aircraft type: Variable Diameter Tiltrotor

Purpose: To quantify VDTR performance and

handling qualities in terminal area operations.

2. High Speed Civil Transport 4 (HSCT 4)

Oct 7 - 18 (FB); Oct 21 - Nov 21 (VMS)

Aircraft type: High Speed Civil Transport

Purpose: To investigate handling qualities, control

requirements and guidance concepts for this type of

aircraft.

3. The Technical Control Panel 1 (TTCP 1)

Dec 2 - 5 (FB); Dec 9 - Dec 27 (FB)

Aircraft type: UH-60 Black Hawk helicopter

Purpose: To investigate a helmet-mounted display

alerting system.

4. Space Shuttle Vehicle (SSV)

Dec 28 - Feb 1 (FB); Jan 6 - Feb 7 (VMS)

Aircraft type: Space Shuttle Orbiter

Purpose: To study the directional control handling

qualities and other orbiter landing issues.

5. Comanche

Jan 27 - Feb 13 (FB)

Aircraft type: RAH-66

Purpose: To implement and validate the math model.

6. Advanced Short Takeoff and Landing (ASTOVL)

Feb 24 - Mar 7 (FB); Mar 31 - Apr 18 (VMS)

Aircraft type: ASTOVL Lift Fan Aircraft

Purpose: To study the control mode integration and

head-up display conformality.

7. The Technical Control Panel 2 (TTCP 2)

Mar 3 - Mar 27 (VMS)

Aircraft type: UH-60 Black Hawk Helicopter

Purpose: To demonstrate the helmet mounted

display alerting system.

8. CH-53 Accident Investigation

Mar 3 - Mar 17 (VMS)

Aircraft type: CH-53D

Purpose: To investigate a CH-53D accident.

9. Slung Load 4 (SLOAD 4)

Apr 21 - May 16 (VMS)

Aircraft type: UH-60 Black Hawk helicopter

Purpose: To further study cargo-class helicopter

operations with an external load.

10. Space Shuttle Vehicle (SSV)

June 2 - July 11 (VMS); June 16 - July 27 (VMS

Demo)

Aircraft type: Space Shuttle orbiter

Purpose: To study the directional control handling

qualities and other orbiter landing issues.

11. High Speed Civil Transport 5 (HSCT 5)

July 14 - Aug 14 (VMS)

Aircraft type: High Speed Civil Transport

Purpose: To investigate handling qualities, control

requirements and guidance concepts for this type of

aircraft.

12. Partial Authority (PARTAUTH)

Aug 18 - Sept 11 (VMS)

Aircraft type: CH-53 helicopter

Purpose: To study the effects of partial-authority

control laws on longitudinal handling qualities.

13. Boeing-1

Sept 1 - Sept 11 (FB); Sept 22 - Oct 17 (VMS)

Aircraft type: JSF

Purpose: To test control law refinement, flying

qualities development and pilot induced oscillation.

VMS Technical Upgrades

1. Transport Cab (TCAB)

Purpose: To support the special needs of the Civil

Tiltrotor and High Speed Civil Transport programs.

2. Virtual Laboratory (VLAB)

Purpose: To develop, integrate and operate a remote-access system that facilitates interactive

participation for off-site VMS customers.

3. Simulation Fidelity Requirements (SIMFR)

Purpose: To improve simulation fidelity by evaluating

and modifying the motion and visual cueing system

performance.

(FB) - Fixed Base Simulators

(VMS) - Vertical Motion Simulator
Aeronautical Test and Simulation Division 11

FY97 Projects Summaries

CVSRF Flight Simulation Projects

1. Tactical Decision-Making System (TDMS)

Nov. 5 - Nov. 22 (ATC)

Purpose: To examine workload issues for Free-Flight

and the transition from an overloaded free-flight

environment to a ground controlled environment.

2. Propulsion Controlled Aircraft 2 (PCA 2)

Nov 25 - Dec 20 (B747)

Purpose: To examine the use of a fly-by-throttle

control system as a backup primary flight control

system for a four engine transport aircraft in the

event of an emergency or malfunction.

3. Converging Approaches

Jan 6 - Jan 17 (B747)

Purpose: To examine potential operational efficiencies during converging approach operations utilizing

the capabilities of modern flight management

systems.

4. TRACON-Flight Management System (FMS)

Trajectory Synthesis 2

Feb 3 - Feb 21 (B747)

Purpose: To evaluate the human factors issues

associated with pilots’ abilities to fly optimized

trajectory approaches utilizing the advanced automation capabilities of today’s flight management

systems and data-link.

5. Advanced Air Transportation Technologies (AATT)

Free Flight 2

Mar 17 - Mar 31 (B747)

Purpose: To evaluate the “alert” and “protected”

zone airspace definitions for free flight and pilots

interpretations of applying visual flight rules right-ofway procedures to the “free flight” environment.

6. Obstacle Free Zone (OFZ)

Jan 6 - Jan 17, Apr 28 - May 14, Jun 16 - Jul 2

(B747)

Purpose: To define the safe spacing and dimension

requirements for new and existing large transport

aircraft when conducting aborted takeoffs or balked

landings below established decision heights.

7. Wide Area Augmentation System (WAAS) Bias

Error

June 16 - July 6 (B747)

Purpose: To examine the maximum bias error

acceptable to pilots for Category I landings in large

carrier aircraft when conducting Wide Area Augmentation System (WAAS), like precision approaches.

8. Aural Alerting

July 14 - 18 (B747)

Purpose: To evaluate whether or not the aural height cue

enhances pilot performance during landing operations.

9. Decision-Making

Aug 28 - Oct 8 (B747)

Purpose: To examine flight crew communications in low

and high risk situations, and how these risks affect pilots

decision-making.

CVSRF Technical Upgrades

1. 747-400 Simulator Visual System Upgrade

Purpose: Increase the fidelity of the 747-400 simulator’s

visual system in order to enhance its realism for human

factors and airspace operations research, primarily during

ground operations.

2. Advanced Concept Flight Simulator (ACFS) Upgrade

Phase 3

Purpose: To ensure the simulator remains capable of

supporting mission critical research in the areas of human

factors and aviation safety for NASA.

Special Events

1. Civil Tiltrotor's 20th Anniversary

May 22 (VMS)

Aircraft type: Civil Tiltrotor

Purpose: To commemorate the 20th anniversary of the

XV-15 development and first flight.

2. NASA Ames Open House

Sept. 18 - 20 (VMS & CVSRF)

Aircraft type: Civil Tiltrotor, 747, ACFS

Purpose: To demonstrate the Ames simulation capabilities

to the community and visitng VIPs.

(ATC) - Air Traffic Control Simulator

(B747) - Boeing 747 Simulator
12 Aeronautical Test and Simulation Division

FY98 VMS Simulation Projects

PROJECT PROGRAM CUSTOMERS TEST OBJECTIVES

SUPPORTED

Boeing DoD Boeing, NASA Ames, Investigate handling qualities, control requirements and

US Air Force, Marines, & Navy guidance concepts for an lift fan type of aircraft.

Boeing-A1DoD Boeing NASA Ames, Investigate an advanced flight control system as well as(Advanced Flight US Air Force, Marines, & Navy handling qualities, control requirements and quidanceControl Systems 1) for a lift fan type of aircraft.Simulation Fidelity Requirement - 5 Other Lockheed Martin, Improve simulation fidelity by evaluating and modifyingpilot-vehicle NASA Ames the motion and visual cueing system performance.

This particular simulation period focuses on linear oscillations.

Civil Tiltrotor 7 AST FAA, NASA Ames Continue investigation of tiltrotor aircraft vertiport design,(CTR7) terminal area operations and certification issues.Lockheed DoD Lockheed Martin, NASA Ames, Investigate handling qualities, control requirements and

US Air Force, Marines, & Navy guidance concepts for a lift fan type of aircraft.

Space Shuttle Space Ops Rockwell, Honeywell, JSC Study directional contol handling qualities and other

orbiter landing issues.

OH-58 DoD US Army, NASA Ames In vestigate techniques being developed to support the DoD

Air Platform, rotary wing sub area to improve the agility andmaneuverability of the OH_58D Kiowa Warrior aircraft.

ADS33 DoD US Army, NASA Ames To access, develop and revise the Army’s rotor craft

handling qulaitites specification, the ADS-33D by usingthe Army/NASA/UH-60 helicopter model and the VMS.

Catagory-A FAA FAA, NASA Ames To evaluate flight procedures, advanced cockpit displays,One Engine Inoperative pilot inceptor cueing, and auditory cueing which assist the(CATA-OEI) pilot in conducting safe optimal recoveries from engine

failures.

Boeing - 2FY98 DoD Boeing, NASA Ames, Investigate handling qualities, control requirements and

US Air Force, Marines, & Navy guidance concepts for a lift fan type of aircraft.

Boeing-A2 DoD Boeing, NASA Ames, Investigate an advanced flight control system as well as(Advanced Flight US Air Force, Marines, & Navy handling qualities, control requirements andControl Systems 2) guidance concepts for a lift fan type of aircraft.High Speed Civil AST Boeing, NASA Ames Investigate handling qualities, control requirements andTransport 7 (HSCT7) guidance concepts for a high speed type of aircraft to be

used for civilian transport.

Partial Authority DRA US Army, NASA Ames Apply and evaluate a new Partial Authority SCAS concept

integrated in a helicopter.

Slung Load DoD US Army, NASA Ames Study cargo-class helicopter operations in a degraded

visual environment with an external load.

Space Shuttle Space Ops Rockwell, Honeywell, JSC Study directional contol handling qualities and other

orbiter landing issues.
Aeronautical Test and Simulation Division 13

FY98 Planned Simulation Projects

Decision Making TAP NASA Flight Management & Examine flight crewcommunications in low and high risk

(747-400) Human Factors Division situations, and how these risks affect pilots decision making.

Propulsion Controlled Aircraft PCA NASA Ames, NASA Dryden Evaluate the use of a low cost fly-by-throttle control law

(747-400) systems as an emergency backup flight control system in

the event of a hydraulic system failure.

Taxiway Navigation & Situation TAP/LVLASO NASA Flight Management & Increase safety and efficiency of aircraft movement on the Awareness (T-NASA) (ACFS) Human Factors Division airport surface through use of a Head Up Display (HUD) &

Electronic Moving Map (EMM).

Obstacle Free Zone FAA FAA Aeronautical Center Explore airspace and dimension requirements for new and

(747-400) (Oklahoma City) large transport aircraft to conduct aborted takeoffs or

landings in below weather minimums.

Air-Ground Communications AATT NASA Flight Management & Evaluate human factors issues associated with the use of

(747-400) Human Factors Division automated air-ground communications in high density

terminal area operations.

Cockpit Situational Display AATT NASA Flight Management & Examine the use of advanced self separation and traffic andFeatures (747-400) Human Factors Division collision avoidance system display symbology in support of

free-flight.

Propulsion Controlled Aircraft PCA NASA Ames, NASA Dryden Evaluate the use of a low cost fly-by-throttle control law

(ACFS) systems as an emergency backup flight control system in

the event of a hydraulic system failure.

Multiple Parallel Approaches FAA FAA Technical Center Evaluate traffic handling capabilities and spacing require-

(747-400) ments for running multiple simultaneous parallel approach

operations.

Taxiway Navigation & Situation TAP/LVLASO NASA Flight Management & Increase safety and efficiency of aircraft landing & taxing on Awareness (T-NASA) (ACFS) Human Factors Division the airport surface through integrating T-NASA and a Roll

Out & Turn Off (ROTO) system.

Airborne Instrumentation for TAP NASA Langley Evaluate independent instrument approach operations toLateral Spacing (AILS) (747-400) closely spaced parallel runways in adverse weather

conditions utilizing advanced/emerging technologies.

Flight Replanning AATT NASA Flight Management & Assess flight crews’ strategies for making flight replanning

(747-400) Human Factors Division decisions under current or “free flight”rules.

CTAS/FMS Data-link AATT NASA Flight Management, Investigate pilot performance utilizing automatic data-link of

(ACFS) FAA CTAS approaches into on-board Flight Management

Computers (FMS).

Roles & Responsibilities AATT NASA Flight Management & Explore the determination of roles & responsiblities

(747-400) Human Factors Division between the ground operators and pilots in the “free flight”

environment.

FY98 CVSRF Simulation Projects

PROJECT PROGRAM CUSTOMERS TEST OBJECTIVES

SUPPORTED
14 Aeronautical Test and Simulation Division
VMS Projects

Aeronautical Test and Simulation Division 15

Vertical Motion Simulator

Research Facility

The Vertical Motion Simulator

(VMS) complex is a world-class

research and development facility that

offers unparalleled capabilities for

conducting some of the most exciting

and challenging aeronautics and

aerospace studies and experiments.

The six-degree-of-freedom VMS, with

its 60-foot vertical and 40-foot lateral

motion capability, is the world's largest

motion-base simulator. The large

amplitude motion system of the VMS

was designed to aid in research issues

relating to controls, guidance, displays,

automation and handling qualitites of

existing or proposed aircraft. It is an

excellent tool for investigating issues

relevant to nap-of-the-earth flight, and

landing and rollout studies.
16 Aeronautical Test and Simulation Division

Variable Diameter Tiltrotor

Karen Studebaker, NASA ARC

Steven Belsley, Philip Tung, Norm Bengford, Logicon Syscon/Syre

Summary

The Variable Diameter Tiltrotor is a Sikorsky

Aircraft Corporation concept in which the rotors

change diameter during flight in an attempt to optimize the performance characteristics of the rotor. The

rotor operates at maximum diameter in helicopter

mode and decreases in size during conversion to

66% diameter in airplane mode (Figure 1). This small

diameter in airplane mode has the benefit of reduced

tip speed for low noise and results in higher propulsive efficiency.

Introduction

In 1992, a wind tunnel test was conducted jointly

by Sikorsky and NASA of a 1/6-scale Variable

Diameter Tiltrotor (VDTR) rotor. The rotor was

successfully converted between helicopter and

airplane modes by remotely changing the rotor

diameter and nacelle angle. Figure 2 shows the

blade retraction mechanism from the test consisting

of a jackscrew which moved an outer blade in and

out over an inner torque tube to change diameter.

This demonstrated the feasibility of the VDTR

concept and motivated continued VDTR development

including the current simulation activity to address

the challenges of the Short Haul Civil Tiltrotor (SHCT)

Program.

The simulation's primary objective was to quantify

the performance and handling quality characteristics

of the VDTR to that of a fixed diameter tiltrotor CTR8/96, for a SHCT mission. The test points included

steep approach procedures, terminal one engine

inoperative (OEI) approach and departure procedures, and all engine inoperative procedures.

Related research includes ongoing VDTR activity

such as vehicle sizing and economic analysis for the

SHCT mission, proprotor aerodynamic design

optimization and acoustic analysis. Also planned are

isolated rotor and full-span wind tunnel tests at Ames

and Langley tunnels.

Simulation Results

Preliminary results showed that both aircraft

exhibited Level I, or satisfactory handling qualities

during normal operations. However, for the more

demanding tasks such as 9-degree instrument

approaches, OEI operations and power-off autorotations, the VDTR exhibited superior performance and

improved handling qualities.

For example, VDTR Category A type continued

takeoff distances were typically 1/3 of that required

by the fixed diameter tilt rotor, and rejected takeoff

distances were about 1/2.

During Category A type landing procedures, the

VDTR’s ability to safely fly at lower airspeeds with

one engine inoperative enabled it to be flown on a 9

degree glide slope to a lower decision height than the

fixed diameter tiltrotor aircraft, resulting in a more

comfortable approach and landing touchdown.

Evaluation pilots were universally enthusiastic

about the performance improvements attributable to

the VDTR’s lower disk loading and higher rotor

inertia. Pilot workload during power-off autorotations

was significantly reduced with touchdown airspeeds

as low as 25 knots; about half of that of the fixed

diameter tiltrotor case.

Investigative Team

The Boeing Company

Sikorsky Aircraft

Federal Aviation Administration

NASA Ames Research Center

Figure 2. The VDTR blade used in the 1992 wind tunnel

test.

Figure 1. The VDTR shown airplane and helicopter

modes.
VMS Projects

Aeronautical Test and Simulation Division 17

Summary

This piloted VMS investigation studied the selection of an optimum arrangement of flight control

inceptors for the High Speed Civil Transport. Results

indicated a slight preference for a center-mounted

stick over the wheel column or sidestick.

Introduction

The High Speed Research (HSR) program is a

collaborative effort among NASA and the Boeing

Aircraft and McDonnell Douglas Aerospace companies. The goal is to develop the high leverage technologies necessary for an environmentally acceptable, economically viable high speed civil transport

(HSCT) that provides a three hundred passenger,

Mach 2.4, intercontinental service beginning in the

year 2005. In support of this goal, the HSR program’s

Guidance and Flight Controls (GFC) team is conducting a series of simulations and flight tests designed to

validate guidelines and methods to meet the flying

qualities and certification criteria for an HSCT development program.

The VMS has played a significant part in its

development. There have been seven HSR simulation sessions at the VMS since 1993. These simulations researched flight control systems, guidance

algorithms, HUD issues, and aircraft configurations.

The simulations used Boeing's basic airframe model,

which has been evolving since its first release in July,

1994. Each new release incorporates further wind

tunnel testing, computational fluid dynamics analyses,

and modeling improvements.

High Speed Civil Transport 4

Dan Dorr, Joe Conley, NASA ARC

Chris Sweeney, Robert Morrison, Emily Lewis, Logicon Syscon/Syre

The simulation objective was to provide handling

quality comparisons and pilot commentary of wheel/

column, center stick, and side stick control inceptors

to support the GFC team's inceptor recommendation.

Simulation Development

Simulation modifications showed incremental

gains being made toward the HSCT development.

The baseline used was the Ref H-Cycle IIb version

of the Boeing basic airframe model. Routines for the

Boeing flight control system were updated from the

previous simulation as was the McDonnell Douglas

lateral-directional control system. Modifications were

made to the landing gear side force model and the

wind model for better realism. A soft-stop was added

to the pitch and roll axes of the wheel and column

and side stick inceptors.

Remarkable competence and efficiency was

shown by the VMS hardware group. The test plan

called for each pilot to evaluate three control inceptors. This required the exchange of inceptors being

pulled out of the cab and replaced by another

inceptor on a daily basis. Reconfiguration included

disassembling the cab, removal of the incepter,

installation of another inceptor and reassembling the

cab. Final steps included verification of the entire

simulation system with each new installation.

Simlab's performance demonstrated its versatility

and flexibility in meeting our customer requirements.

Simulation Results

Preliminary results indicate a slight pilot preference for the center stick. Of the ten pilots in the

study, three significantly preferred the center stick,

one preferred the wheel and column, and one

preferred the side stick. Others said any of the

control inceptors would be acceptable with training,

because they did not identify any handling qualities

deficiencies between the three choices.

Investigative Team

Boeing Aircraft Company

McDonnell Douglas Aircraft Corp.

NASA Ames Research Center

The goal is to develop the high leverage technologies

necessary for an environmentally acceptable,

economically viable high speed civil transport.
18 Aeronautical Test and Simulation Division

The Technical Control Panel 1

Joseph DeMaio, U.S. Army ATCOM

Luong Nguyen, Logicon Syscon/Syre; Duc Tran, NASA ARC

Summary

A helmet-mounted display equipped with an

ambient vision system was evaluated for alerting the

pilot. It was also compared to the conventional panelmounted display. Improved performance reduced

response times, and favorable pilot comments were

noted.

Introduction

This was the first experiment in a series to evaluate a novel approach to alerting through the helmetmounted display using the pilot’s ambient vision

system. The ambient system allows perception

without attention, making it the primary visual pathway for alerting an observer to a change in an

unattended part of the visual field. The ambient

system draws from the entire retina, and the strength

of its output is proportional to the area of the retina

stimulated. Therefore, it is most effective when there

is a sudden change in the stimulation of a large

retinal area.

The second objective established the interaction

between the field-of-view of the display and the area

reserved for symbology. Past work showed that

presentation of symbology at an angular separation

that is greater than twenty degrees from the center of

the display is not very effective. Therefore, it might be

expected that the effective field-of-view for symbology might be restricted to about 40 degrees, while

that for imagery might be 80 to 100 degrees. The

research examined acceptability and effectiveness of

symbolic arrays that are 40 degrees wide when they

are superimposed upon imagery displays of the

same or greater fields-of-views.

Simulation Results

Overall, the ambient helmet-mounted display

(HMD) alerting mode eliminated very long (> 6 s)

response latencies. It was speculated that such long

latencies occur because the pilot becomes absorbed

in flying and forgets the alert. The reduced set of test

field-of-views yielded comparable flying performance

results to those obtained with larger sets in prior

research. Results also showed that the HMD alerting

was not disruptive and pilots’ comments were generally favorable.

Investigative Team

British Defense Evaluation Research Agency

Hughes Training Systems

NASA Ames Research Center

The ambient system allows perception without attention,

making it the primary visual pathway for alerting.

10

48 %

5

5

40K 746

10

15

10

15 33 03

The HMD ambient vision system above shows the

symbology used to alert the pilot.
VMS Projects

Aeronautical Test and Simulation Division 19

Summary

The Shuttle orbiter landing and rollout studies are an

ongoing part of the Space Program. Every six months

simulations are performed at the VMS to fine-tune the

Shuttle orbiter’s landing systems. Nose gear loads,

aiming point position vs. speed brake angle, drag chute

deployment speed, and single Auxillary Power Unit

landings were investigated. Also, upcoming crews and

astronaut candidates were provided training.

Introduction

The Space Shuttle orbiter model has been simulated at SimLab since the late 1970s. The basic model

has evolved and matured over the years. The simulation at Ames has been used to test flight control

improvements, safety features, head-up display

development, proposed flight rule modifications, and

model changes. The guidance and controls include the

latest modifications (OI-24). The simulation is also

used to give astronauts realistic landing and roll out

scenarios, including some with system failures, as part

of the training.

Many of the Shuttle orbiter’s components were

investigated and evaluated. Objectives included: (1)

Studying the effects of an extended nose gear strut

with I-load changes to the flight control system, and

evaluating the effects of the nose gear extension on

slapdown, gear loads, load persistance and derotation

speed. (2) Studying the vehicle’s handling qualities and

performance using the close-in aimpoint versus a large

speedbrake angle, and evaluating the pilots preference. (3) Studying a proposed flight rule to deploy the

drag chute ten knots prior to derotation. (4) Studying

the effects of a single Auxillary Power Unit (APU)

landing. (5) Provide upcoming crews and astronaut

candidates with training.

Simulation Results

The data gathered on the extended nose gear strut

showed the proposed lengths of seventeen and

twenty-five inches were found to greatly reduce the

maximum gear load on the main gear struts. No

adverse roll out handling qualities were observed.

Preliminary results further showed that an extended

nose strut and a change to the elevon trim position

during slapdown would allow the orbiter to survive a

tire failure.

Data gathered on the vehicle’s handling qualities

and performance using the close-in aimpoint versus a

large speedbrake angle showed that handling qualities

Space Shuttle Vehicle

Howard Law, NASA JSC

Chris Sweeney, Estela Hernandez, Leslie Ringo, Logicon Syscon/Syre

are not a problem with a large speedbrake angle

landing. The findings were in view of the main concern

with landing into a head wind, the inner aimpoint may

be required to have enough energy to land. Another

concern was landing into a tail wind, which may result

in the degradation of handling qualities. Pilots did not

have a preference between the large speedbrake

angle or close-in aimpoint. Other considerations, such

as sun glare, were of greater concern.

Another preliminary result was the flight rule for the

drag chute may be modified to specify that drag chute

deployment should be ten knots prior to derotation for

all vehicles. The final study of the single Auxillary

Power Unit showed that a single APU landing may be

handled as long as the pilot minimizes control inputs in

order to avoid control surface saturation.

The training session of the simulation reinforced the

importance of the VMS in preparing upcoming crews

for the landing and roll out phase as well as for possible failures at that time.

Investigative Team

Boeing North American

NASA Ames Research Center

NASA Johnson Space Center

Rockwell International

Rockwell Space Operations Company

The orbiter model used in this simulation was the baseline

model used previously at the VMS complex with model

options and improvements specific to this simulation.
20 Aeronautical Test and Simulation Division

Summary

The purpose of this simulation was to implement

the RAH-66 Comanche math model and validate the

entire flight envelope on the VMS. U.S. Army and

Sikorsky personnel concluded that the implementation of the real-time, pilot-in-the loop math model was

both accurate and complete.

Introduction

The RAH-66 Comanche is a reconnaissance/

attack helicopter being developed by the BoeingSikorsky team as a replacement for the U.S. Army’s

OH-58 Kiowa Warrior and the AH-1 Cobra helicopters. The U.S. Army’s Aeroflightdynamics Directorate

(AFDD) began an effort in 1993 to acquire a realtime, pilot-in-the-loop Comanche simulation. The

contract was awarded to Boeing-Sikorsky in 1994 to

provide engineering documentation and check cases

for the Comanche math model. Subsequently,

SimLab engineers were assigned the task to code

and verify the complete computer model.

The goal of the simulation was to validate the

entire flight envelope of the real-time Comanche

math model and correct any discrepancies in the

SimLab version of the model.

The complex math model for Comanche was

entirely implemented and integrated by SimLab

engineers over a period of two years. Sikorsky

provided the airframe model and Boeing provided the

control system. The major subsystems modeled

were: the airframe, rotor (using blade element

approach), engine/fuel control, drive train, core and

mission Primary Flight Control System (PFCS), and

the Automated Flight Control System (AFCS). The

final step was to validate the model with a pilot-inthe-loop fixed-base simulation this February at

SimLab. The goal of the simulation was to verify the

math model implementation at SimLab and validate it

over the entire flight envelope of the Comanche.

Comanche

John Mayo, Sikorsky; Hossein Mansur, U.S. Army, AFDD

Chuck Perry, Leslie Ringo, Logicon Syscon/Syre

Simulation Results

Prior to the fixed-base session, the model was

rigorously verified by running a multitude of static and

dynamic checks at the module and system level.

During fixed-base operations, the model validation

was accomplished by test pilots flying specific tasks

as defined in the "Handling Qualities Requirements

for Military Rotorcraft (ADS-33)" document and other

aggressive maneuvers designed to exercise the

entire flight envelope of the helicopter. Four NASA

pilots and one Syre pilot flew over 250 data runs as

well as numerous additional runs to flush out and

correct any discrepancies in the model.

The U.S. Army and Sikorsky investigative team

declared the simulation to be successful and were

very satisfied with the accurate implementation of this

first real-time Comanche simulation model. AFDD

now has a fully validated, pilot-in-the-loop,

Comanche model ready for future simulations at the

SimLab facility. The model has also been transferred

to an AFDD workstation where it is used for engineering studies.

Investigative Team

U.S. Army, AFDD

NASA Ames Research Center

Sikorsky Aircraft

SimLab engineers were assigned the task to code and

verifiy the complete computer model for a real-time, pilotin-the-loop Comanche simulation.
VMS Projects

Aeronautical Test and Simulation Division 21

Advanced Short Takeoff and Vertical Landing

James Franklin, NASA ARC

Steven Belsley, Norm Bengford, Phil Tung, Logicon Syscon/Syre

Summary

A piloted simulation of an Advanced Short Takeoff

and Vertical Landing Lift Fan aircraft was conducted

to demonstrate control mode integration and head-up

display conformality to Joint Strike Fighter program

participants. Major contributions to Joint Strike

Fighter design and operational procedures were

realized, and the unique capabilities of the VMS were

also demonstrated.

Introduction

NASA Ames Research Center is participating in

technology development for advanced short takeoff

and vertical landing fighter aircraft as a member of

the Advanced Research Projects Agency's (ARPA)

Advanced Short Takeoff and Vertical Landing

(ASTOVL) program. Integration of flight and propulsion controls is one of the critical technologies being

pursued in that program. NASA’s role is to develop

design guidelines for integrated flight/ propulsion

controls, support ARPA technology development for

ASTOVL demonstrator aircraft, and provide consultation on integrated control design to ARPA contractors.

Specifically, NASA will carry out design guidelines

analyses for the control system and conduct piloted

simulations on the Ames Research Center Vertical

Motion Simulator to assess the merits of contending

design approaches.

A piloted simulation of an ASTOVL Lift Fan aircraft

was conducted on the Vertical Motion Simulator. The

simulated aircraft was a Harrier-like strike fighter with

a propulsion system consisting of a turbofan liftcruise engine equipped with a two-dimensional cruise

nozzle in addition to vectorable lift nozzles and a

shaft-driven lift fan for low speed and hover flight.

This experiment investigated control mode integration and head-up display conformality over a range of

STOVL aircraft operations applicable to that of the

Joint Strike Fighter (JSF). Ames was joined by

engineers and pilots from the U.S. Marine Corps and

Navy, the United Kingdom Defense Research

Agency, and Boeing and Lockheed Martin, the two

contractors competing in the JSF program.

The specific objectives for the experiment were as

follows: (1) Evaluate the integration of the throttletype controller with flight control laws that provide for

controllability during transition from cruising flight to

hover. (2) Evaluate control mode blending for pitch,

roll, yaw, and flightpath control during transition. (3)

Evaluate the effect of conformal vs. non-conformal

HUD presentation of flightpath and guidance symbology. (4) Demonstrate advanced control and display

systems for STOVL operations to visiting JSF program pilots and engineers.

Simulation Results

The demonstrations gave the JSF visitors a view

of alternative control design concepts and how they

function for all aspects of STOVL operations,

landbased and aboard ship. The simulation allowed

all involved to experience ground operations, short

and vertical takeoffs, transition to and from cruise

flight, approach to landing, precision hover, and

vertical and slow landings. They were able to see

how the various control modes blended from one

flight phase to another and the interface of the

controllers and cockpit displays with these modes.

The government and industry participants departed with a number of applications to design their

flight control systems and cockpit interface. They also

recognized the unique capability that the VMS offers

for evaluating their respective designs.

Investigative Team

The Boeing Company

British Defense Research Agengy

Lockheed Martin

NASA Ames Research Center

U.S. Marine Corps

This experiment investigated control mode integration and

head-up display conformality over a range of STOVL

aircraft operations.
22 Aeronautical Test and Simulation Division

The Technical Control Panel 2

Joseph DeMaio, U.S. Army ATCOM

Luong Nguyen, Logicon Syscon/Syre; Duc Tran, NASA ARC

Summary

The second experiment in The Technical Control

Panel series, evaluated a helmet-mounted display

alerting system. The alert signals the pilot to attend to

an immediate issue in the cockpit. In addition, two

navigation displays, which were integrated into the

helmet-mounted display to supplement paper or

moving maps, were also investigated. It was found

that a timely alert response was achieved with the

ambient alert system. Neither of the two navigation

displays was particularly effective when the moving

map was available as a head-down display.

Introduction

The Technical Control Panel (TTCP) series of

experiments evaluate a novel approach to alerting

the pilot through the helmet-mounted display using

the pilot’s ambient vision system. The ambient

system allows perception without attention, making it

the primary visual pathway for alerting an observer to

a change in an unattended part of the visual field.

The ambient system draws from the entire retina, and

the strength of its output is proportional to the area of

the retina stimulated.

This simulation was the second experiment in the

series. The objectives of this simulation were: (1) To

compare an ambient visual processing Helmet

Mounted Display (HMD) alert with a focal processing

alert to draw the pilot’s attention into the cockpit. The

ambient alert consisted of flashing of all symbology

displayed on the HMD. The focal alert consisted of

flashing only the alert symbol itself. The pattern of

stimuli and responses were similar to that on the AH64 Comanche. The pilot’s response was measured in

a laboratory task intended to capture the characteristics of an actual flight procedure. (2) To evaluate two

navigation displays integrated into the HMD display,

similar to the Comanche, with an “instrument”

presented on the HMD.

The simulation used the UH-60 math model and

an IHADSS HMD with standard AH-64 cruise mode

symbology. Two focal and two ambient alerts were

used in the display, informative and non-informative.

Focal and ambient flashing was defined as in the

TTCP1 simulation.

Simulation Results

Preliminary analysis shows that: (1) The low alert

frequency, stresses the pilot’s vigilance in a realistic

way, resulting in occasional missing of alerts. This

tendency to miss alerts was eliminated by the

ambient alert presentation. (2) Neither of the two

navigation displays was particularly effective when

the cockpit moving map was available. When the

moving map was made stationary, the pilots were

able to use the nav aid displays. The Course Deviation Indicator (CDI) did not provide a clear indication

when the pilot had passed the waypoint, and if the

pilot strayed from the course, neither CDI or Lolipop

waypoint marker provided adequate information to

avoid disorientation.

Investigative Team

British Defense Evaluation Research Agency

Hughes Training Systems

NASA Ames Research Center

U.S. Army ATCOM

68 %

30 33 N 03 06

0 K 23

69 %

22 24 N 30 33

1 K 26

68 %

30 33 N 03 06

0 K 23

Three helmet-mounted displays are shown. The first, at left, shows a lollipop symbology that indicates the next waypoint

is to the left. The middle display shows a short angled line beneath the N that indicates the waypoint is to the left by 50

degrees. And the far right display, shows a short straight line below the N that indicates the waypoint is directly ahead.
VMS Projects

Aeronautical Test and Simulation Division 23

CH-53 Accident Investigation

Summary

This simulation was effectively used to assist

members of an investigation team in analyzing the

cause of a fatal accident involving a mid-air collision

of two CH-53D helicopters. A study of the recreated

trajectories of the two helicopters indicated that one

of them may have unknowingly descended upon the

other.

Introduction

On February 4, 1997 at 7:00 P.M., two Israeli Air

Force (IAF) CH-53D helicopters collided while

ferrying troops, killing all 73 passengers and crew. An

accident investigation committee was formed to study

the incident and to discover why it had occurred. Two

members of the accident investigation team contacted the Vertical Motion Simulator (VMS) SimLab

for assistance.

The request for help was received on the 3rd of

March. A math model of the CH-53 helicopter was

brought up. Verification of the model and integration

with the existing cab in the VMS was completed

during the 1st week of March. The capability of

driving and viewing two separate CH-53D graphical

images was also verified.

The simulation goals were identified as: (1) To

recreate the last two minutes of flight of the IAF CH53D helicopters to help give insight into the accident.

(2) To create a video showing the collision of the

helicopters from varying viewing angles. (3) To

recreate the final thirty seconds of the incident when

one of the helicopters inflight tail section broke off

and the helicopter spun to the ground.

The accident investigation team members arrived

on March 10th with eyewitness testimony and a radar

map of the positions of the two helicopters. The radar

map contained eleven points for one helicopter and

sixteen points for the other during the final ninety

seconds of flight. These points were time tagged, but

did not include altitude data. Since this map was two

dimensional and the time of each point was not

correlated, the investigation team members wished to

get a graphical viewing of the events leading to the

collision.

The map was placed on a digitizing tablet and the

positions of the points were recorded into a file. This

Zvi Avigal, Israeli Air Force

Chris Sweeney, Robert Morrison, Logicon Syscon/Syre

file was reformatted to be read real-time into the

drives for the two helicopters. After fine tuning the

trajectories to make the helicopters fly reasonably

well, without the jerkiness apparent with so few data

points, runs were recorded on video. The video

showed sixty different angles of the collision, including each of the pilot's views, “chase plane” viewpoints of the incident, a view from the eyewitness

perspective, and straight overhead views. The

investigation team left March 13th with the desired

data and videos as well as a better understanding of

the collision.

Simulation Results

As the primary goal of the simulation, the trajectories of the two CH-53D helicopters were successfully

replayed and video recorded. These trajectories led

the accident investigation team to re-examine the

original hypothesis of how the collision may have

occurred. Results indicate that one helicopter may

have unknowingly drifted over the flight path of the

other helicopter before descending practically on top

of it; however, more analysis of the crash site and

tapes is needed before a final conclusion can be

reached.

Preliminary results of the accident investigation indicate

that one helicopter may have unknowingly drifted over the

flight path of another helicopter before descending

practically on top of it.
24 Aeronautical Test and Simulation Division

Slung Load 4

Chris Blanken, U.S. Army AMCOM

Bob Morrison, Soren LaForce, Luong Nguyen, Logicon Syscon/Syre

Summary

The US Army’s heavy cargo helicopter, the Boeing

CH-47D “Chinook,” was simulated for the U. S. Army

Aeroflightdynamics Directorate. In support of the U.S.

Army’s Improved Cargo Helicopter program, the

aircraft was simulated with and without external slung

loads. Findings will be used to upgrade the cargo

helicopter through the year 2025.

Introduction

The fourth experiment in the Slung Load series,

was conducted by the Aeroflightdynamics Directorate

(AFDD) with participation from Boeing Helicopter,

ATTC at Ft. Rucker, R. Heffley Engineering, and Hoh

Aeronautics, Inc. The focus of the experiment was to

obtain further data for expanding the U.S. Army’s

rotorcraft handling qualities specification (ADS-33D),

which includes cargo helicopters, especially for slung

load operations. This research is being conducted in

support of the U.S. Army’s Improved Cargo Helicopter (ICH) program, which is a plan to upgrade its

cargo helicopters in order to sustain them through the

year 2025. In addition, this research is needed to

correct deficiencies in the helicopters that adversely

affected their mission operations during Desert

Storm.

For the experiment, the Boeing CH-47D “Chinook,”

the U.S. Army’s heavy cargo helicopter, was simulated with and without an external slung load weighing 16,000 pounds. With a slung load, the dynamics

of the aircraft are affected by not only the basic

aircraft response but the coupled response from the

external load configuration.

The experiment had the following principal objectives: (1) Refine the pitch and roll bandwidth data

base relative to the current boundaries using the

ADS-33D tasks and their equivalent cargo/slung load

tasks. (2) Refine the definition/characterization of

heading hold. (3) Add roll-due-to-yaw and yaw-dueto-roll coupling requirements.

Simulation Results

Various configurations of the helicopter, with and

without a slung load and with different control gains,

were investigated. The configurations included single

and dual point suspended loads with various sling

lengths and hook-to-aircraft-cg distances.

Five pilots, two from NASA Ames and one each

from the U.S. Army, Boeing, and Syre, flew the

different configurations to perform the lateral reposition, precision hover, hover turn, and acceleration/

deceleration tasks to assess handling qualities with

and without a slung load. Frequency sweeps of the

configurations were performed with a pilot in the cab

in both motion and fixed base. The researcher

analyzed the data using comprehensive identification

from frequency responses (CIFER) to determine

bandwidths. The experiment was very successful,

completing 1,693 runs and meeting all principal

objectives.

Investigative Team

U.S. Army Aeroflightdynamics Directorate

Airworthiness Qualification and Test Directorate

Boeing Defense & Space Group,

Helicopter Division

NASA Ames Research Center

Hoh Aeronautics Inc.

R. Heffley Engineering

Naval Air Test Center

Various configurations of the helicopter, with and without

a slung load and with different control gains, were

investigated.
VMS Projects

Aeronautical Test and Simulation Division 25

Space Shuttle Vehicle

Howard Law, NASA JSC

Chris Sweeney, Estela Hernandez, Logicon Syscon/Syre

Summary

Space Shuttle orbiter landing and rollout studies

are conducted at the VMS to evaluate the Shuttle

orbiter’s landing systems. The major goal of this

simulation was to study the proposed forward expansion of the center of gravity envelope. This experiment indicated that the center of gravity expansion

results in acceptable handling qualities and structural

safety margins for the orbiter.

Introduction

The Space Shuttle orbiter has been simulated at

SimLab since the late 1970s. The basic model has

evolved and matured in the intervening years. The

simulation at Ames has been used to test flight

control improvements, safety features, head-up

display development, proposed flight rule modifications, and orbiter model changes. The simulation is

also used to give astronauts realistic landing and

rollout scenarios, including some scenarios with

system failures, before their flight. The guidance and

controls include the latest modifications (OI-27).

The simulation objectives were: (1) Evaluate

forward center of gravity (c.g.) limit expansion. The

space station assembly flights will require a more

forward c.g. than is currently certified. The effect of

this forward movement on nose gear slapdown rates,

main gear loads, and handling qualities were studied.

(2) Evaluate an extended nose gear with the proposed center of gravity extension. (3) Study a flight

rules issue concerning ceilings and visibility. (4)

Study tire failure/tire certification flight rules. (5)

Evaluate the usefulness of the Ames Virtual Laboratory (VLAB) at JSC.

Simulation Development

Model development for this simulation focused on

ensuring the nose gear slapdown and main gear

loads data generated at Ames agreed with the high

frequency Boeing North American loads simulation.

After a week of data collection, a discrepancy was

found between the Ames data and the loads simulation. Many comparison checks were run and the

runs disclosed that the loads simulation was running

with an old aerodynamic database. After updating

the aerodynamics, the loads simulation delivered a

new aero increment for the main gear loads and the

simulations matched more closely. The tire failure

model was updated to include the temperature and

pressure of the tires.

Simulation Results

Results of the forward c.g. expansion study

indicate acceptable handling qualities and structural

safety margins for accepting the more forward c.g..

Preliminary results of the extended nose gear study

show an increase in safety margin with the longer

nose gear as well as no degradation in handling

qualities. Preliminary results of the visibility and

ceiling matrix indicate the flight rules should remain

at the current levels as lowering the ceilings and

visibility does not give enough benefits. Preliminary

results of the tire failure study show no changes

should be made to flight rules due to low pressure or

low temperature tires. Results of the VLAB trial at

JSC were very successful. The researchers who

saw VLAB thought it was a great tool and should be

used for all orbiter simulations.

Investigative Team

The Boeing Company

Lockheed Martin

NASA Ames Research Center

NASA Johnson Space Center

United Space Alliance

The major goal of this simulation was to study the

proposed forward expansion of the center of gravity

envelope.
26 Aeronautical Test and Simulation Division

High Speed Civil Transport 5

Tod Williams, Boeing; Gordon Hardy, Logicon Syscon/Syre

Chris Sweeney, Robert Morrison, Joe Ogwell, Jennifer Moga, Logicon Syscon/Syre;

Duc Tran, NASA Ames

Summary

A two-phase piloted experiment was conducted for

the High Speed Research program. Part one studied

flight envelope protection, head-up display symbology, and some preliminary vertical guidance algorithms. Part two studied the refinement of the lateral

flying qualities criteria for High Speed Civil Transport,

specifically the roll control effectiveness criterion, and

evaluated the lateral-directional characteristics of the

current model.

Introduction

The High Speed Research program is a collaborative effort between NASA and The Boeing Company.

The goal of this effort is to develop the high leverage

technologies necessary for an environmentally

acceptable, economically viable, High Speed Civil

Transport (HSCT) providing a three hundred passenger, Mach 2.4, intercontinental service beginning in

the year 2005. In support of this goal, the HSR

program’s Guidance and Flight Controls team is

conducting a series of simulations and flight tests

designed to validate guidelines and methods to meet

the flying qualities and certification criteria for an

HSCT development program.

Part one goals were to provide pilot opinion

regarding the current state-of-flight control envelope

protection, downselect a variety of head-up display

(HUD) symbology, and give feedback on the current

vertical guidance algorithms. Part two goals were to

refine the lateral flying qualities of an HSCT and

evaluate the lateral-directional characteristics of the

current aircraft model.

Simulation Development

The airframe model was upgraded to Ref. H-Cycle

III for this simulation. The major revisions for the

upgrade were to the aerodynamic database and the

engine model. The Cycle III aero model included data

from three Langley wind tunnel tests. The longitudinal

flight control system was updated as was the lateraldirectional flight control system. Modifications were

made to the HUD driver in order to display various

new symbols needed for part one of the simulation.

Simulation Results

Part one results indicated that pilots believed the

envelope protection (annunciation and flight control

system intervention when limits were exceeded) was

appropriate for the aircraft. They felt that it could

have been more aggressive in preventing the pilot

from exceeding structural limits. The preliminary

guidance algorithms were acceptable, and the added

HUD symbology was helpful. Part two data is helping

to define a database of acceptable criteria for an

HSCT.

Investigative Team

The Boeing Company

Federal Aviation Administration

Honeywell

NASA Ames Research Center

 A series of simulations and flight tests are designed to

validate guidelines and methods to meet the flying

qualities and certification criteria for an HSCT

development program.
VMS Projects

Aeronautical Test and Simulation Division 27

Partial Authority

Chris Blanken, U.S. Army AMCOM

Estela Hernandez, Luong Nguyen, Logicon Syscon/Syre

Summary

This simulation experiment was conducted in

preparation for a flight test program to develop a

flight control system upgrade for an Improved Cargo

Helicopter. The Improved Cargo Helicopter program

will sustain the CH-47D fleet into the next century.

Since it was not possible to flight test all significant

variants of the existing analog flight control system,

they were simulated at the VMS instead. The simulation objective was to explore two types of variations.

The first was to explore variations in baseline system

parameters (Boeing 8/4/97 version), and the second

was to explore alternative mechanization concepts.

Introduction

The Boeing CH-47D “Chinook” is the US Army’s

heavy cargo helicopter. The Chinook first flew as the

YCH-47 in September 1961. There have been

several modernization plans over the years which

have upgraded the aircraft from the A-model to the

“B-”, “C-” and to its present CH-47D configuration.

The first D-model has been in service for 15 years

since its remanufacture. As the end of the century

approaches, CH-47D’s operational costs will increase

and its readiness will deteriorate as the aircraft reach

the end of their economic life.

At the request of the U.S. Army Aviation and

Missile Command (AMCOM), the U.S. Army Airworthiness Qualification Test Directorate (AQTD),

located at Edwards Air Force Base, conducted

handling qualities flight tests with a CH-47D. The

purpose of these flight tests were to document the

CH-47D dynamic response characteristics and to

develop and refine a set of flight test maneuvers

specifically for evaluating cargo helicopters and sling

load operations. The results of the AQTD flight test

formed a basis from which piloted simulations have

been conducted by Boeing and the U.S. Army

Aeroflightdynamics Directorate (AFDD) toward

development of criteria for this size and class of

helicopter. These simulations have been used to

investigate different control response types and

dynamics, different aircraft load configurations,

reduced thrust margins, interactions between the

slung load and the aircraft Advanced Flight Control

System, and the potential for achieving attitude

stabilization through the partial authority control

system.

This simulation was the last opportunity to investigate/resolve issues prior to submitting initial handling

qualities requirements for the Improved Cargo

Helicopter program. The focus of this simulation was

to refine the CH-47D partial-authority control laws to

improve the longitudinal handling qualities for aggressive maneuvering. Based on the VMS investigation of

alternate control laws, the best designs will be

implemented into a CH-47D flight control computer

and flight tested at the U.S. Army Aviation Technical

Test Center, Ft. Rucker, Alabama.

Simulation Results

Pilots from the Army, NASA, Navy, and Boeing

flew 1159 data runs, which included a variety of low

altitude, low speed precision flight task. In addition,

some forward flight tasks were evaluated. These

consisted of an Instrument Landing System (ILS)

approach, transition to hover, missed approach and

traffic pattern back to the ILS. A total of eight flight

control system variations were studied. After further

analysis of the data, the best designs will be identified and selected for flight testing at Ft. Rucker, AL.

Investigative Team

U.S. Army Aeroflightdynamics Directorate

Aviation Technical Test Center

Boeing Defense & Space Group, Helicopter Division

NASA Ames Research Center

Hoh Aeronautics, Inc.

R Heffley Engineering

Naval Air Systems Command

The Boeing CH-47D “Chinook” is the US Army’s heavy

cargo helicopter. There have been several modernization

plans over the years which have been used to upgrade the

aircraft.
28 Aeronautical Test and Simulation Division

Boeing-1

Boeing Aircraft Company

William Chung, James Franklin, NASA ARC

Chuck Perry, Leslie Ringo, Girish Chachad, Al Sanchez, Logicon Syscon/Syre

Summary

A piloted simulation of Boeing’s X-32 Joint Strike

Fighter (JSF) design was conducted as part of their

design and development process. Boeing ran their

aircraft model on SimLab’s large motion VMS to

complement their in-house simulation. Boeing, U.S.

and U.K. Service, and NASA test pilots evaluated

Boeing’s JSF design utilizing the unique capabilities

of the VMS.

Introduction

NASA Ames Research Center is playing a key role

in support of the U.S. government’s Joint Strike

Fighter (JSF) Program which will field an affordable,

highly common family of next-generation multi-role

strike fighter aircraft for the Navy (USN), Air Force

(USAF), Marine Corps (USMC), United Kingdom

Royal Navy and other U.S. allies. The Military

Services have stated their needs for the JSF as

follows:

• USN - first day of war, survivable strike fighter

aircraft to replace the A-6 and F-14 and complement

the F/A-18E/F

• USAF - multi-role aircraft (primary-air-to-ground)

to replace the F-16 and A-10 and to complement the

F-22

• USMC - STOVL aircraft to replace the AV-8B and

F/A-18A/C/D

• United Kingdom Royal Navy - STOVL aircraft to

replace the Sea Harrier

The Boeing Company is one of two manufacturers

selected to build and fly a pair of (X-32) JSF Concept

Demonstration Aircraft (CDA). Real-time, piloted flight

simulation is an important step in Boeing’s approach

to JSF design and development. Simulations using

the large motion-base at Ames’ VMS were conducted

by Boeing to complement their in-house simulation

efforts prior to conducting in-flight simulations and

flight testing. The objectives of the VMS simulation

included control law refinement, flying qualities

development, pilot-induced oscillation (PIO) analysis.

Besides Boeing pilots, Navy, Air Force, Marine

Corps, United Kingdom Royal Air Force and Royal

Navy and NASA test pilots participated in the evaluations.

The simulation ran fixed-base for two weeks,

followed by 4 weeks of motion-based operations. The

fixed-base session was primarily to validate the

simulation system, finalize flight tasks and scenarios

and exercise data collection processes in preparation

for the motion-base experiment. The validation was a

critical step since the computer code for the entire

aircraft model generated by Boeing was integrated

into SimLab’s simulation environment. The validation

was performed with Boeing personnel on site.

 Simulation Results

The primary objectives of the simulation were met,

and 819 piloted evaluation runs were completed.

Pilots from Boeing, U.S. and U.K. Services and

NASA were favorably impressed with the important

part that large motion cueing played in enhancing

their evaluations of Boeing’s JSF flying qualities and

mission capabilities in general.

For SimLab, this simulation marks the first time

that a customer’s entire aircraft model has been

integrated into SimLab’s real-time system. Also,

special security measures were put in place to

safeguard information relating to Boeing’s simulation

hardware and software due to the competition

sensitive nature of the project, thus limiting the

details contained in this write-up.

Note: For further information regarding the Boeing

JSF program, please refer to the Boeing and JSF

Program Office World Wide Web pages:

http://www.boeing.com

VMS Projects

The Joint Strike Fighter is envisioned as the next

generation fighter to replace several aircraft in service

with the United States Air Force, Navy, Marines, the

United Kingdom Royal Navy and several other countries.
Aeronautical Test and Simulation Division 29

Civil Tiltrotor's 20th Anniversary

William Decker, NASA ARC

Steve Belsley, Philip Tung, Logicon Syscon/Syre

Summary

Ames Research Center celebrated the 20th

Anniversary of the first flight of the XV-15 Tiltrotor.

After hundreds of hours of flight, the XV-15 is still a

critical link in tiltrotor research and future development of this technology.

Introduction

On May 22, 1997, Ames Research Center celebrated the 20th Anniversary of the first flight of the

NASA/ Army/ Bell XV-15 Tiltrotor Research Aircraft. A

new era in aviation was introduced with the V-22

Osprey tiltrotor aircraft and the announcement of the

Model 609 Civil Tiltrotor by Bell Helicopter Textron

and Boeing Helicopters. The technology development and the demonstration of capability achieved

with the XV-15 was essential to the launching of

these aircraft. As such, the XV-15 Tiltrotor Research

Aircraft is one of the most versatile aircraft ever

designed.

Tiltrotor aircraft combined features of helicopters

and fixed-wing aircraft. They have the vertical takeoff

and landing capability of the helicopter and the cruise

speed, range, and fuel economy of fixed-wing

aircraft. Tiltrotors achieve this by the use of

proprotors that operate like helicopter rotors during

takeoff and landing, then tilt to provide horizontal

thrust acting like turboprops during cruise.

The development of the XV-15 Tiltrotor was

initiated in 1973 with joint NASA/Army funding, and

SimLab was involved from the start to support its

development. In the early 70’s, the Flight Simulator

for Advanced Aircraft (FSAA) was used for XV-15

simulation, evaluation and contractor downselect to

Bell. By the mid 70’s, the FSAA assisted the design

and development of the XV-15 prior to its first flight.

The late 70’s and early 80’s saw the XV-15 further

developed and its operational use evaluated. Also at

this time, a transition was made from the FSAA to the

Vertical Motion Simulator (VMS). Early 80’s research

led to the V-22 program and evaluations of the Army

LHX. Finally, the Civil Tiltrotor (CTR) series began in

1989 and is still in development.

The Event

To help commemorate this 20th Anniversary, a

Civil Tiltrotor was configured on the VMS in order to

showcase its unique capabilities. The CTR-6 simulation math model and cockpit hardware arrangement

were utilized for the demonstration. Visitors were

able to monitor the pilot’s cockpit displays as well as

observe the VMS motion system excursions. An

Ames research pilot flew the approaches while the

project engineer described the various approach

segments and associated operational procedures.

Special Event

The development of the XV-15 tiltrotor research aircraft

was initiated in 1973 with joint Army/ NASA funding as a

"proof of concept", or "technology demonstrator"

program, with two aircraft being built by Bell Helicopter

Textron.

One way the commercial tiltrotor aircraft could help

reduce airport congestion and traffic delay problems

would be by using off-airport vertiports for urban area to

urban area and city center to city center service, diverting

travelers away from crowded hub airports and their access

roads.
30 Aeronautical Test and Simulation Division
Aeronautical Test and Simulation Division 31

CVSRF Projects

Crew-Vehicle Systems

Research Facility

The Crew-Vehicle Systems Research Facility, a

unique national research resource, was designed for the

study of human factors in aviation safety. The facility is

used to analyze performance characteristics of flight crews;

formulate principles and design criteria for future aviation environments; evaluate new and contemporary air traffic control procedures; and develop new training and simulation

techniques required by the continued technical evolution of flight systems.

Studies have shown that human error plays a part in 60 to 80 percent of all aviation accidents. The CrewVehicle Systems Research Facility allows scientists to study how errors are made, as well as the effects of

automation, advanced instrumentation, and other factors, such as fatigue, on human performance in aircraft.

The facility includes two flight simulators-- a Boeing 747-400 and an Advanced Concepts Flight Simulator as

well as a simulated Air Traffic Control System. Both flight simulators are capable of full-mission simulation.
32 Aeronautical Test and Simulation Division

Summary

An experiment was conducted to determine

Dynamic Density, which characterizes the transition

from unconstrained flight to constrained flight, or from

free-flight to ground based Air Traffic Control flight.

Additional goals of the study were to identify controller techniques used to transition between control

types, evaluate two alert zone graphical displays, and

compare route efficiencies for constrained and

unconstrained flight.

Introduction

One of the concepts for increasing airspace capacity

is the implementation of “free flight,” which allows

aircraft on instrument flight plans to provide their own

separation independent of ground controllers. Important issues are to determine at what traffic density this

becomes a problem and how to safely revert to

ground-based control of the aircraft separation. To

study these issues, the CVSRF Air Traffic Control

(ATC) simulator was configured to use three of the four

sector displays as “pilot” stations and one as an ATC

Controller Station. Actual FAA controllers performed as

both pilots and controllers. Three of the controllers

were positioned at the pilot sector displays and each

controlled several aircraft in free-flight mode. They

were provided with graphical conflict alert ellipses

around each aircraft in order to identify aircraft flight

paths in conflict. They would then radio the other

aircraft crew and agree on a maneuver to avoid

collision. A fourth controller, stationed at the ATC

controller station sector display, was to intervene if the

aircrafts were not able to maintain safe separation.

Tactical Decision-Making System

Irene Laudeman, NASA ARC

Connie Brasil, San Jose State University

The Air Traffic Control (ATC) simulator was configured to

use three of the four sector displays as “pilot” stations and

one as an ATC Controller Station.

Simulation Results

For this study, the ATC simulator was modified to

support 20 ATC sector displays, which provided

stations for 19 pilots and one controller. Data was

collected regarding Dynamic Density, procedures,

alert zone graphical displays, and route efficiencies

for constrained and unconstrained flight. A second

experiment is planned to further study the performance of pilots concurrently. Although the experimental setup is complete, the series of studies has

been put on hold pending NASA and FAA agreement

on program responsibility issues.
Aeronautical Test and Simulation Division 33

CVSRF Projects

Summary

The second experiment in the PCA series, examined the use of a fly-by-throttle control system as a

backup flight control system in the case of an emergency, or malfunction to an airplane’s primary flight

control system.

Introduction

Over the years, numerous aircraft accidents have

been caused as a result of primary flight control

system failures. Most vivid is the Sioux City, Iowa

incident, where the primary flight controls of a United

Airlines DC-10 were rendered inoperable due to a

loss of hydraulic power. The pilots were able to land

by skillfully manipulating the engine controls, and

successfully saved many lives. Subsequent to this

accident investigation, the National Transportation

Safety Board (NTSB) recommended to NASA the

need to “encourage research and development of

backup flight control systems for newly certified widebody airplanes that utilize an alternate source of

motive power separate from that source used for the

conventional control system.”

In compliance with the NTSB recommendation,

NASA-Dryden in conjunction with Ames Computational Sciences Division, conducted a study which

further examined the use of a fly-by-throttle control

system as a backup flight control system in case of

an emergency, or malfunction to an airplane’s

primary flight control system. This experiment, called

the Propulsion Controlled Aircraft (PCA) 2 study,

evaluated the PCA control laws for the 747’s full

operational envelope in realistic, worst case scenarios. The PCA concept was originally developed at

NASA-Dryden, using a two-engine aircraft. Later, this

study was moved to NASA-Ames and tested on the

Advanced Concepts Flight Simulator, using two- and

three-engine aircrafts. Recently, after evaluating PCA

control algorithms, it was performed on the 747-400

simulator, using a four-engine aircraft.

Propulsion Controlled Aircraft 2

 Robert Mah, NASA ARC

John Bull, CAELUM Research Corp.

Simulation Results

The PCA control laws essentially allow pilots to fly

an aircraft using only the throttles for pitch and roll

commands, without the use of the airplane’s primary

flight control systems. When PCA mode is selected,

the airplane’s pitch and roll commands are controlled

by the vertical speed and heading select knobs on

the airplane’s Mode Control Panel. Using the throttle

commands, thrust inputs are translated through

software into equivalent pitch and roll commands,

allowing pilots to maintain control of the malfunctioning aircraft.

Various scenarios were examined such as jammed

controls, hydraulic and engine failures, and out-oftrim roll and yaw moments. Data collected during

these runs included performance metrics of aircraft

state data, touchdown snapshots, Cooper-Harper

Ratings Scale, and post-simulation pilot questionnaires. Participating pilots represented NASA, the US

Air Force, Boeing and United Airlines. Findings

showed that subject pilots rated the PCA control laws

satisfactory to adequate using the Cooper-Harper

ratings. It was also determined that the PCA performed well during single-engine failures, recoveries

from unusual attitudes (including high altitude conditions), and at aft center-of-gravity conditions.

This simulation focused on the adaptability of the PCA

control laws for a four-engine aircraft during approach

and landing operations.

VERT SPD

TRACK

VERTICAL

SPEED

DN

UP

Flight

Control

Computer

Flight Path 

& Track 

Command

-1000

Pilot

Inputs

Flight Path Angle

Bank Angle/Track

Right Throttle Command

Left Throttle Command

HDG

230
34 Aeronautical Test and Simulation Division

Summary

Potential operational efficiencies were further

tested, utilizing the capabilities of modern flight

management systems during converging approach

operations.

Introduction

This series of study, conducted by the System

Capacity Office, Federal Aviation Administration

(FAA) in Washington D.C., in cooperation with the

Standards Development Branch at the FAA Aeronautical Center in Oklahoma City, tests increasing airport

capacities to develop a standard for air-carrier

airplanes equipped with state-of-the-art Flight Management Systems (FMS). Also studied are simultaneous Instrument Landing System (ILS) approaches

and missed approaches on a primary traffic flow

runway and on a converging runway by airplanes

utilizing a modern FMS. The FAA with participation

from the airlines, aircraft manufacturers and oversight

agencies have been investigating flight-track data

obtained as a result of using high-end FMS equipped

air-carrier-aircraft simulators when operating with

FMS Lateral Navigation (LNAV) guidance. To further

enhance data previously obtained, additional testing

is necessary to assess the safety aspects of the

converging missed approach during FMS LNAV

tracking as well as evaluating flight-crew human

factors issues.

Converging Approaches

Ralph Dority, FAA System Capacity Office, Washington D.C.

Allen Jones, Frank Hasman, FAA Standards Dev. Branch, Oklahoma City

Barry Scott, FAA Field Office, NASA ARC

Simulation Results

This experiment was designed to examine the use

of a revised missed approach procedure for FMS

equipped aircraft. Specific goals were to determine:

1) aircraft geographic position relative to the runway

threshold position during missed approach procedures, 2) aircraft state versus geographic position

during the missed approach maneuvers, and 3) if

there are any human performance issues associated

with flying these specialized procedures. The experiment examined the use of a lateral course offset from

the localizer using Chicago O’Hare’s runway 4R and

the aircraft’s FMS for positive guidance during the

converging missed approach operation. To support

the converging missed approach, a customized FMS

database was provided by Honeywell through the

FAA, in order for pilots to fly the given procedure.

Conclusive statements are pending.

This simulation examined the use of a revised missed

approach procedure for FMS equipped aircraft.

Converging Approaches

MAP

MAP

MAP: Missed Approach Point

TERPS: Terminal Procedures

nmi: Nautical Miles

At least 3 nmi required

Non-Overlapping TERPS
Aeronautical Test and Simulation Division 35

CVSRF Projects

TRACON-Flight Management System Trajectory Synthesis 2

Summary

A pilot’s ability to fly optimized trajectory approaches utilizing today’s flight management systems

and advanced features such as data-link was evaluated.

Introduction

The Human-Automation Integration Research

Branch of the Flight Management & Human Factors

Division conducted a study on the 747-400 simulator

to evaluate the feasibility of using current data-link

messages to perform Flight Management System

(FMS) operations in the terminal area. Quantitative

flight path tracking data (using FMS data) were

compared to similar results of an earlier study, but

flown manually or as autopilot assisted. Trajectory

approaches for both studies were generated by the

Center TRACON Automation System (CTAS), which

was developed by NASA. CTAS is an automated air

traffic control system designed to allow more efficient

flight in the national airspace system without jeopardizing safety. Other factors studied were the effects

of various arrival procedures on pilot workload,

communications and coordination, and head-down

time. This study was conducted in support of the

Terminal Area Productivity (TAP) Program.

Simulation Results

Scenarios consisted of approaches from the

southeast, with landings to runway 17C at the DallasFort Worth International (DFW) Metroplex. Line

qualified 747-400 crews participated in this study.

Data collection included aircraft position and state

data, videotapes and pilot questionnaires. In addition

to the quantitative flight path tracking data that was

collected, subject pilots were asked to provide ratings

of the FMS approach procedures and phraseology to

determine whether Future Air Navigation System

(FANS) messages and data-link interfaces are

acceptable for terminal area operations.

Rhonda Slattery, NASA ARC

Beverly Sanford, Katherine Lee, Sterling Software

Preliminary results indicate the necessity for clear

representation of the exact route changes on the

pilot’s navigation displays, with the ability to review

previous clearances as compared to the new routes,

and to depict route compliance with airspace restrictions. In addition, subject pilots had acceptability

issues using the FANS data-link messages with the

tested procedures. Speculation suggests this may be

due to FANS messages, which were originally

designed for the oceanic arena and not the terminal

area. Other issues included timeliness of reviewing

changes, inexperienced pilots using vertical navigation (VNAV) in the terminal area, and the amount of

head-down time it took the pilots to review and

implement the revised route changes. Conclusive

statements are pending.

A study was conducted on the 747-400 simulator to

evaluate the feasibility of using current data-link messages

to perform Flight Management System (FMS) operations

in the terminal area.
36 Aeronautical Test and Simulation Division

Summary

This study evaluated the “alert” and “protected”

zone airspace definitions for free-flight and investigated pilots’ interpretation of Visual Flight Rules rightof-way procedures and their application to the freeflight environment.

Introduction

The Human-Automation Integration Research

Branch of the Flight Management & Human Factors

Division conducted a study to evaluate the “alert” and

“protected” zone airspace definitions for free-flight

and investigate pilots’ interpretation of Visual Flight

Rules (VFR) right-of-way procedures and their

application to the free flight environment. In the freeflight environment, aircraft will presumably be able to

maneuver with more autonomy. However, free-flight

will require the definition of new zones around each

aircraft, similar to the zones currently provided by the

Traffic Alerting and Collision Avoidance System

(TCAS) alert algorithms. These zones will be defined

as the “alert” and “protected” zones. Further, roles

and responsibilities associated with the transgression

of these zones need to be defined and evaluated.

Unlike an earlier experiment in this series, this test

examined higher density levels of traffic.

The continued use of a new alerting scheme logic,

developed by MIT, further defined “alert” and “protected” zones around the ownship of an aircraft and

provided intruder information up to 100 miles beyond

the currently used TCAS zones. The “alert” zone is

defined by a complex algorithm based on the spatial

geometry between an aircraft’s ownship position and

that of an intruder, the probabilities of a conflict, and

the ability to maneuver out of the conflict. The

“protected” zone is within the alert zone and is

defined as the separation distance of five miles

between two aircraft. In order to make the flight crew

aware of their situation with respect to other aircraft,

new symbology was also developed and integrated

on the flight crew’s navigation displays. Whenever an

intruder penetrates the “alert” zone of the 747,

prediction lines extend from the 747’s ownship

position to the point of closest approach on its route,

as well as from the intruder aircraft’s ownship to the

point of closest approach on the 747’s route. At that

time, an aural warning is triggered to alert the 747’s

flight crew.

Advanced Air Transportation Technologies Free Flight 2

Another tested feature was the use of a customized “predictor” control panel. This control panel

enabled subject pilots to determine the position of

intruders up to ten minutes ahead of time in order to

avoid possible encounters or potential collisions.

Simulation Results

Experiment runs consisted of several enroute

scenarios flown in the Denver airspace. Scenarios

involved the 747 simulator and other pseudo-aircraft

generated by the CVSRF’s Air Traffic Control (ATC)

simulator. Depending on the threat levels of the

pseudo-aircraft, subjects were required to negotiate

with another aircraft and to execute an avoidance

maneuver. Data runs, with the assistance of linequalified 747-400 flight crews, consisted of four

training legs and eight data recorded legs, including

videotapes and pilot questionnaires. Conclusive

statements are pending.

Sandy Lozito, NASA ARC

Alison McGann, Margaret-Anne MacKintosh, Patricia Cashion, San Jose State University

In this display, the position of intruder airplanes are

depicted by chevrons as well as their predicted positions in

seven minutes which are shown by the circles, and their

corresponding predictor lines extrapolated from their

current positions.
Aeronautical Test and Simulation Division 37

CVSRF Projects

Summary

Large aircarrier aircraft flight-tracks and heightloss arrest points were explored and analyzed

relative to Obstacle Free Zone space and dimension

requirements.

Introduction

The Federal Aviation Administration’s (FAA)

Standards Development Branch in Oklahoma City,

conducted a series of studies to explore large

aircarrier aircraft flight-tracks and height-loss arrest

points as a result of crew-induced aborted or balked

landings after reaching decision-height altitude and

beyond; to a minimum of 50 ft above ground level.

Approaches using both auto-land and manual flight

procedures were conducted in Categories I and II

weather conditions, respectively, and analyzed

relative to Obstacle Free Zone (OFZ) space and

dimension requirements. Findings will be used in the

development of FAA standards and operations

criteria and to assist The Boeing Company in new

large airplane design.

Obstacle Free Zone Balked Landings

Barry Scott, FAA Field Office, NASA ARC

Frank Hasman, Allan Jones, FAA Standards Development Branch, Oklahoma City

The Advisory Circular 150/5300-13, Airport Design

is used to prescribe runway design dimensions for

various elements of large airplanes affecting runway

utilization, such as runways, shoulders, blast pads,

clearways, runway safety areas, and separation

requirements to adjacent taxiways. Runway elements

and OFZ dimensions are referenced to airplane

design groupings based on wingspan. These groupings account for wingspans up to but not including

262 ft. For planning future airplane wing designs

exceeding 262 ft, data is required to assure that the

OFZ needed by these airplanes is calculated to

provide operationally safe conditions below the

decision-height altitude under all expected conditions

of flight.

Simulation Results

Three tests were conducted on the 747-400

simulator throughout this year. The first test studied

approaches designed to land at runway 4R at

Chicago’s O’Hare Airport. Flight-track and height-loss

data, occurring subsequent to arrival at Categories I

and II decision-height altitudes, were collected for

missed approach and aborted/balked landings.

Particular attention was given to conditions (i.e.

extreme winds and gross weight) allowable for the

type of approach being tested and their possible

impact on OFZ required space and crew response/

techniques. Data collection included digital readouts

of aircraft state and performance data, videotapes

and pilot questionnaires. The other two tests focused

attention on aborted takeoffs, engine-out takeoffs and

traffic conditions. Conclusive statements are pending.

Traditional missed

approach

Balked landing/

climb out Decision

height

The Obstacle Free Zone will provide operationally safe

conditions below the decision-height altitude.
38 Aeronautical Test and Simulation Division

Summary

This study examined the maximum bias error

acceptable to pilots for Category I landings in large

aircarrier aircraft, such as the B-747, while conducting Wide Area Augmentation System-like precision

approaches.

Introduction

The Standards Development Branch at the

Federal Aviation Administration (FAA) Aeronautical

Center in Oklahoma City, examined the maximum

bias error acceptable to pilots for Category I landings

in large aircarrier aircraft, such as the B-747, using

Wide Area Augmentation System (WAAS)-like

precision approaches. Because a bias error changes

the aircraft aimpoint on the runway rather than just

the angle of the glidepath and threshold crossing

height, questions are raised about pilot acceptability

of the system. Unlike an Instrument Landing System

(ILS), the vertical guidance on a WAAS precision

approach could be misleading after reaching visual

conditions and could provide information which

conflicts with the pilot’s visual picture and visual

landing aid systems. This study supported the FAA in

determining the integrity limit for WAAS precision

approaches. Further testing may be required to

determine ceiling and visibility requirements for

actual WAAS approaches, while accounting for

variations between Visual Approach Slope Indicator

and Precision Approach Path Indicator systems, as

well as various lighting systems.

Wide Area Augmentation System Bias Error

Barry Scott, FAA Field Office, NASA ARC

Steve Jackson, Frank Hasman, Standards Dev. Branch, Oklahoma City

The vertical guidance on a WAAS precision approach

could be misleading after reaching visual conditions and

could provide information which conflicts with the pilot’s

visual picture and visual landing aid systems.

Simulation Results

To simulate a bias type error, Catgeory I approaches were conducted with the Glide Path

Intercept point offset along the runway. Bias errors of

plus or minus ten meters vertically were introduced

into the scenarios, which offset the glideslope

intercept point plus or minus 626 ft horizontally along

the runway. Each scenario was set up for approaches into runway 35L at the new Denver International Airport. Results were analyzed relative to

vertical flight track, threshold crossing height, touchdown point, number of missed approaches, vertical

speed required for correcting to the actual glidepath

for landings, and pilot comments gathered via post

approach questionnaires. Conclusive statements are

pending.
Aeronautical Test and Simulation Division 39

CVSRF Projects

Summary

The aural height cue was examined to determine

pilot performance during landing operations in large

transport category-type aircraft.

Introduction

The Human Information Processing Research

Branch, Flight Management & Human Factors

Division, in conjunction with researchers from

McDonnell-Douglas, conducted a study to quantitatively determine the handling qualities effects of the

aural height cue during landing operations. Correlation of results with previous large airplane handling

qualities investigations exposed different touchdown

performances and handling qualities ratings for

similar aircraft-types. A hypothesis is that the presence of the aural height cue improved touchdownlanding performance and handling qualities ratings.

This study supported the High Speed Research

Program, performed earlier on the Vertical Motion

Simulator.

Simulation Results

The 747-400 simulator was used to conduct a

series of offset approaches and landings. Subject

pilots were asked to fly down a laterally offset

Aural Alerting

Jeffery Schroeder, NASA ARC

Edmund Field, McDonnell-Douglas

glideslope to a predetermined altitude (about 250 ft).

Pilots were then instructed to maneuver the airplane

to land on the runway at a predetermined landing

zone, with and without the help of the aural height

cue. Flight conditions included day, night and dusk

scenes for runway 30 at Long Beach Airport. To make

the approaches more challenging, updrafts were

inserted into the simulations through the 747-400

simulator’s “Microburst” model, which was modified for

this experiment. Approaches were also configured for

landings at both light- and heavy-weight conditions.

The aural height cue was modified for these tests to

“50, 40, 30, 20, 10” as opposed to “50, 30, 10”, which

is the normal 747-400 aural height cue during landing

operations. Test pilots from NASA Ames, NASA

Dryden, McDonnell-Douglas and the U.S. Air Force

participated in this study. Conclusive statements are

pending.

ARRESTING WIRE

ADEQUATE

PERFORMANCE

DESIRED

PERFORMANCE

30

AIMPOINT

ILS/GLIDEPATH

INTERCEPT POINT

2.5

MIDDLE MARKER

200'

AGL

300'

LATERAL OFFSET

CL

Subject pilots were asked to fly down a laterally offset glideslope to a predetermined

altitude (about 250 ft). Pilots were then instructed to maneuver the airplane to land on the

runway at a predetermined landing zone, with and without the help of the aural height cue.
40 Aeronautical Test and Simulation Division

Decision-Making

Summary

Flight crew communications in low and high risk

situations were examined and analyzed with regard

to pilot decision-making.

Introduction

The Aviation Safety Research Branch, Flight

Management & Human Factors Division, conducted a

study to determine factors that influence pilots’

success in monitoring and detecting problems.

Identified problems were pilot- or in-flight errors and

communication strategies used to call attention to or

correct problems. In a 1994 analysis of flight-crewcaused accidents, the National Transportation Safety

Board found 31 out of 37 accidents involved “monitoring and challenging” failures. That is, errors and

problems were left unattended resulting in an unsafe

situation. In most cases, it was the first officer who

was unable to get the attention of the captain, or

induce him to change his decisions or actions. Little

research has been done to determine when crew

members notice problems and decide to intervene,

and what the selection-process is for choosing the

most successful intervention strategy.

Simulation Results

Flight scenarios differed in the degree of pilot-error

or problem, and the level of risk posed by the error or

problem. Pilot-free problems were mainly caused by

either air traffic control, air, traffic, or weather condiJudith Orasanu, NASA ARC

 Jeanie Davison, Laura Tyzzer, Eric Villeda, Lori McDonnell,

Christina Van Aken, San Jose State University

CVSRF Projects

The FAA conducted a study to acquire missed approach

tracking data for use in determining the degree of safety

and landing operations.

tions. Pilot error was interpreted as the verbal

challenge directed to another crew member of

different status. In order to create the “scripted”

scenarios, an experienced 747-400 airline captain,

played either the pilot or first officer role and committed the scripted errors, according to experimental

design. Five different line-oriented flight scenarios

introduced low and high risk situations, each designed to look at three factors: (1) crew position -

captain versus first officer, (2) risk levels, and (3) face

threat (type of problem). Verbal responses to errors

and problems created by air traffic controllers or the

subject pilot constituted the dependent measure. In

addition, the timeliness of pilot response after cues

signaling was analyzed. Conclusive statements are

pending.
Aeronautical Test and Simulation Division 41

Technology Upgrades CVSRF Projects

Transport Cab (TCAB)

Introduction

The aeronautical research done at the VMS

assists in the design and development of cuttingedge technology to meet the aeronautical needs of

the future. Two such programs that have unique

research requirements are the Civil Tiltrotor (CTR)

and High Speed Civil Transport (HSCT). Both

identified a need for a two-seat, side-by-side, wide

out-the-window (OTW) field-of-view (FOV) civil

transport cockpit simulation capability on the Vertical

Motion Simulator (VMS). To support the special

needs of these programs, a fifth interchangeable cab,

designated the Transport cab (TCAB), was designed

and built at the VMS facility.

After a two and a half year effort to design, build

and become certified for Human Occupancy, the

TCAB was completed on May 27, 1997. The TCAB is

a special achievement that provides a newer, larger,

and more capable simulator cab for the future needs

of aeronautics. It is now part of the VMS interchangeable cab system, and “flew” its maiden mission in

July as part of the HSCT-5 simulation.

TCAB represents current and future generation

airliners (e.g. 777, 747-400, MD-11, and A320), which

have a wide OTW FOV. The visual system provides a

270 deg. horizontal field-of-view (HFOV), which is

more than twice the HFOV of any of the four existing

I-cabs used on the VMS. The “all glass cockpit” is an

instrument console that uses cathode ray tubes

(CRT) instead of analog instruments to simplify

cockpit layout design and reduce maintenance costs.

A collimated display of six CRT monitors casts a

high-quality image on six spherical mirrors; the

mirrors are arranged to form a dome-like section

providing a continuous field-of-view image to the pilot

and co-pilot. CRT monitors allow for very low distortion, high brightness, and high resolution image,

which typical dome projection simulator systems are

not capable of producing. This two-seat cockpit

provides both programs the capability to research

flight deck designs, crew coordination, and related

aircraft handling qualities issues. It also provides the

capability towards “full mission” simulation to research the interfaces with the air traffic control

system and other terminal area operations.

A compatible ICAB configuration can be used for

both programs. The HSCT program will operate from

the left pilot seat, and the CTR program will operate

from the right pilot seat. Since the opportunity exists

for both programs to operate the ICAB simultaneously, the TCAB is configured for “quick” equipment exchanges that may be unique to each program.

TCAB Key Features

• A wide out-the-window field-of-vision of 240° X 60°

• A small “chin-bubble” window on the right pilot seat

• A high resolution video mixing of HUD symbology

with the computer generated image (CGI)

• A primary instrument panel that houses six large 8"

X 8" CRTs to present the primary flight displays,

navigation displays, engine information, etc.

• Two control display units (CDUs) in the center

console, one for each pilot

• An audio system to simulate the noise environment

typical within the flight deck

• Video cameras to monitor and record flight crew

activities

Dean Giovannetti, NASA ARC

Hai Huynh, Joel Rosado, Logicon Syscon/Syre

Interior view of the new TCAB with a Civil Tiltrotor outthe-window display.
42 Aeronautical Test and Simulation Division

Virtual Laboratory (VLAB) Demonstrator Project

Introduction

The Virtual Laboratory (VLAB) represents a fresh

approach to conducting simulation experiments. It

allows researchers at remote sites to interactively

participate in live simulation experiments conducted

in research laboratories at the Ames Research

Center.

VLAB uses enabling technology to provide a

virtual reality environment to the remote users, who

can “see” various simulation data as if they were

physically present in the VMS complex. Currently,

VLAB delivers the pilot’s front-window scene, headup and head-down displays, a graphical depiction of

the motion platform, time-history graphs and end-ofrun data displays. Also integrated into the package

are video-conferencing and two-way ambient sound

capabilities for the remote user to actively affect the

conduct of the experiment. Future versions of VLAB

will feature simulation model control, aircraft controls,

display development, virtual prototyping, and data

browsing.

VLAB embodies Ames Research Center’s mission

to lead the world in Information Technology. It allows

government and industry greater access to NASA

expertise in a hands-on fashion. VLAB is an extension of a national research facility that enables

industry to improve and accelerate its design process, yielding cutting-edge, aeronautical products.

Goals

The goal of the VLAB Demonstrator Project was to

develop, integrate and operate a remote-access

system that facilitates interactive participation for offsite VMS customers. Integral to this goal was the

participants’ evaluation of VLAB as a useful research

tool. Answers were sought to questions such as: Did

VLAB allow users the desired level of interaction?

Was the timeliness of information delivered satisfactory? Was the graphical interface inviting and easy to

use? Most importantly, did VLAB further enable the

users to meet their research goals?

Results

The Virtual Laboratory completed a very successful run of tests, demonstrations, and productive

engineering use at the Johnson Space Center. For

six weeks, VLAB provided continuous, highly interactive, remote access to the Space Shuttle approach

and landing simulation being conducted on the

Vertical Motion Simulator at Ames Research Center.

The remote users at JSC emphatically responded

that VLAB is a very useful tool. All research goals

were met. The data transmission rate provided near

perfect “remote fidelity,” with little or no delay, including the video of the out-the-window display. Initial

estimates put the data rate at between 100 and 150

mega bits/second.

The VLAB client was exhibited at the NREN

Workshop, Ames Research Center, and for Ames

Community Day, September 20th. As requested, the

VLAB will be exhibited at Super Computing ’97.

Future Plans

Future work will include enhancing the fidelity of

the “immersive” nature of VLAB; providing additional

“user I/O” features; increasing VLAB’s applicability to

several simulation experiments; collaborating with

technology experts, both within and outside of Ames,

and increasing its diversity by applying the VLAB

technology in areas beyond flight simulation at the

VMS. Other plans include exploring possible partnerships with education and local aeronautics museums.

For more information, including who the principal

contributors were, visit VLAB’s website at:

http://www.simlabs.arc.nasa.gov/vlab

Above is a screen capture of the virtual laboratory

showing the custom displays.
Aeronautical Test and Simulation Division 43

Technology Upgrades CVSRF Projects

Simulation Fidelity Requirements

Goals

To investigate and determine the motion-based

flight simulation cueing requirements for visual and

motion cues. The investigations determined if previous criteria had general applications with respect to

the aircraft characteristics and visual content. Another investigation examined the effects of the motion

platform characteristics, such as small motion versus

large motion, and the task with various control force

gradients.

Investigated simulation cueing requirements

focused on roll-lateral degrees-of-freedom (DOF). By

using the two DOF aircraft response, a lateral

translational task was developed to provide the oneto-one visual and motion cueing response within the

Vertical Motion Simulator. This approach isolated the

perceived motion cueing abnormality, which is a

design parameter to the roll and lateral axes. The

one-to-one motion cueing configuration would then

provide the near-truth motion cues.

Results

Participating pilots from FAA, Lockheed Martin,

NASA and Fort Rucker flew a structured test matrix

that included two aircraft roll damping characteristics

and two visual density contents. Also pilots flew five

motion cueing configurations for the platform characteristics investigation.

Data supported the criteria established from

previous study. Criteria for the visual and motion

cueing fidelity requirements were: (1) Handling

qualities in ground-based flight simulations are

affected by more than visual delay. (2) Synchronized

motion cues can be allowed to lag, not lead visual

cues. (3) Mismatch of no more than 40 msec equivalent time delay between roll and lateral motion cues,

and between the visual cues and roll motion cues is

recommended.

In the motion platform characteristics investigation,

data supported the benefit of the large motion

platform. Under large motion configurations, pilot

handling qualities ratings showed better matches with

predicted handling qualities when control

forcegradient were varied.

William Y. Chung, Jeffrey Schroeder, Walter W. Johnson, NASA ARC

Soren LaForce, Logicon Syscon/Syre

For further information please refer to the following

publications:

“Effects of Vehicle Bandwidth and Visual SpatialFrequency on Simulation Cueing Synchronization

Requirements,” AIAA AFM Conference, August 1997.

“An Initial Evaluation of the Effects of Motion

Platform and Drive Characteristics,” AIAA MST

Conference, August 1997.

“Visual and Roll-Lateral Motion Cueing Synchronization Requirements for Motion-Based Flight Simulations “ AHS 53rd Annual Forum, April 1997

“Effects of Roll and Lateral Flight Simulation

Motion Gains on a Sidestep Task,” AHS 53rd Annual

Forum, April 1997.

“Phase Response Requirements Between CrossCoupled Motion Axes for Handling Qualities Research Simulators,” AIAA MST Conference, August

1996.

An effort by NASA Ames Research Center was made to

determine required cueing fidelities for motion-based

flight simulation operations.
44 Aeronautical Test and Simulation Division

Introduction

To support research objectives of low visibility

conditions and terminal area operations improvement, the NASA 747-400 Simulator was upgraded

with a new Flight Safety International VITAL VIIIi

visual system. The new visual system is a wraparound projector based system, which provides a

cross-cockpit viewing capability and an enhanced

field-of-view (40 degrees vertical by 180 degrees

horizontal). The previous system was a CRT monitorbased system, which did not allow pilots to see

across the cockpit during taxi operations. This was a

limitation when conducting ground operations such

as taxiing. The new visual system will support human

factors research programs such as the Terminal Area

Productivity and the Advanced Air Transportation

Technologies Programs.

Accomplishments

The VITAL VIII(i) visual system includes a new

MultiView display screen, mirror and plenum, three

skylight projectors, optical alignment tools and a new

Image Generator (IG). The system replaces the

previous Flight Safety International VITAL VIIe

system, which was a CRT monitor based system with

a limited field-of-view. The VITAL VIII(i) IG is a threechannel system, which provides full color geospecific

photo scenes from satellite and aerial imagery,

calligraphic lightpoints, elaborate weather and special

effects, weather radar system correlation, and full

continuous time of day viewing capability. The IG

747-400 Visual System Upgrade

also contains improved texture memory and pixel

resolution during both day and night scenes and

comes with numerous customized airport database

scenes and a “reconfigurable airport”, which is

provided to represent any airport that currently does

not exist as part of the visual database library.

Moving models depicting other aircraft and ground

vehicles, weather cells, storms, or storm fronts are

also available.

The new visual system was delivered in October

1996, installed in November and acceptance testing

was completed in December. Level D recertification

of the 747 Simulator by the FAA’s National Simulator

Program Office occurred on December 12th.

Principal Contributors

Barry Sullivan, Matt Blake, NASA Ames Research

Center; Dave Bent, Joe King, Sil Corpuz, Gary

Uyehara, Tom Prehm, David Bayat, Eric Gardner,

Glenn Ellis, Jerry Jones, Elliott Smith, Rod Ketchum,

Dave Brown, Norm Martello, NSI Technology Services Corp.; Flight Safety International.

The new visual system is a wrap-around projector based

system, which provides a cross-cockpit viewing capability

and an enhanced field-of-view (40 degrees vertical by 180

degrees horizontal).
Aeronautical Test and Simulation Division 45

CVSRF Projects

Advanced Concepts Flight Simulator Upgrade Phase 3

Introduction

The goal of the ACFS Upgrade Project is to ensure

the simulator’s capability to continue its support of

NASA mission critical research in the areas of

aeronautical human factors, aviation safety, and

airspace capacity. To accomplish this goal, a comprehensive upgrade of nearly all simulator systems was

performed in order to achieve much higher fidelity

with systems that are flexible, reliable, and inexpensive to maintain. Phase 1 and 2 of the ACFS Upgrade Project were completed in previous years and

comprised the upgrade of many of the simulator

computational systems and the cockpit. This included

the host computer, flight display computers, Experimenter Operator Station (EOS) computers, data

communication systems, the construction of a new

cockpit, including elaborate auto-throttle system, new

flight displays, and new aural cueing system. The

final phase of the upgrade was completed this year

and included the installation of a new projection

visual system, Input/Output (I/O) system, and HeadUp Display (HUD) device. The specific goal of this

final phase was to return the simulator to an operational state and begin conducting experimental

research.

Results

A new simulator enclosure and Flight Safety

International (FSI) MultiView projection system was

installed, which provides 180 degree horizontal fieldof-view (FOV) and 40 degree vertical FOV, presenting both raster and calligraphic images. The new

image generator is a FSI Vital VIII(i), which presents

daylight, dusk, and night scenes with many special

effects and includes databases representing numerous airport areas throughout the world. The FSI

system provides outstanding visual cue performance.

Additionally, a new VME based I/O system was

installed to perform all communication between the

host computer and the analog devices in the cockpit

and a Flight Dynamics Inc. (FDI) HUD projector and

combiner were installed in the simulator. The HUD

system is capable of presenting existing transport

aircraft symbology or new research graphics. The

upgraded simulator achieved Human Occupancy

Review Board (HORB) approval to return to service

on August 25, 1997. The “new” simulator is now

capable of providing an excellent research platform

for current and future NASA airspace operations

research programs.

Plans

The ACFS Upgrade Project is complete. The

simulator has now entered an operational phase

where most resources are dedicated to specific

research programs. An additional effort is currently

underway to significantly enhance the Flight Management System (FMS). This effort includes a team

comprised of personnel from both the Aeronautical

Test and Simulation Division and the Flight Management and Human Factors Division. This system will

be integrated into the ACFS in the beginning of FY98.

Some possible future enhancements to the ACFS

include replacement of some of the cockpit control

panels and the motion electronics to improve reliability and installation of additional software systems

modeling such systems as weather radar.

Simulation Support Team

Matthew Blake, Dean Giovannetti, NASA Ames

Research Center; Dave Bayat, Dave Bent, Don

Bryant, Dave Brown, Bruce Cogan, Sil Corpuz, Anna

Dabrowski, Glenn Ellis, Eric Gardner, Joe King, Vic

Loesche, Cindy Nguyen, Craig Pires, Thomas

Prehm, Hector Reyes, Gary Uyehara, NSI Technology Services Corporation

Technology Upgrades

The new ACFS flight deck and visual scene.
46 Aeronautical Test and Simulation Division

AATT ..................................................... Advanced Air Transportation Technologies

ACAH .................................................... Attitude Command, Attitude Hold

ACARS.................................................. ARINC Communications & Reporting System

ACFS .................................................... Advanced Concepts Flight Simulator

ADS....................................................... Automatic Dependent Surveillance

AFDD .................................................... Aeroflightdynamics Directorate

AGL ....................................................... Above Ground Level

AMCOM ................................................ Aviation & Missile Command, U.S. Army

ANOE .................................................... Automated Nap-Of-the-Earth

AOC DL................................................. Airline Operational Communications Data-Link

AO Div................................................... Aeronautical Test & Simulation Division

AQTD .................................................... Airworthiness Qualification Test Directorate, U.S. Army

ARC ...................................................... Ames Research Center

ASN....................................................... Advanced Simulator Network

ASTOVL ................................................ Advanced Short Takeoff & Vertical Landing

ATC ....................................................... Air Traffic Control

BAC....................................................... Boeing Aircraft Company

BHT ....................................................... Bell Helicopter Textron

British CAA ............................................ British Civilian Aviation Authority (regulatory agency)

CAE....................................................... Canadian Aeronautics & Electronics

CATAPOD ............................................. Category A Terminal Area Procedures

CFIT ...................................................... Controlled Flight Into Terrain

c.g. ........................................................ Center of gravity

CH-47D “Chinook” ................................ Heavy cargo helicopter, U.S. Army

CIFER ................................................... Comprehensive Identification from Frequency Responses

CTAS ..................................................... Center TRACON Automation System

CTR....................................................... Civil Tiltrotor

CVSRF .................................................. Crew-Vehicle Systems Research Facility

DA ......................................................... Descent Advisor

DASH .................................................... Differential Air Speed Hold

DARP .................................................... Dynamic Aircraft Route Planning

DOF (6) ................................................. Six Degree-Of-Freedom

DVE....................................................... Degraded Visual Environment

EICAS ................................................... Engine Indication and Crew Alerting System

EOS ...................................................... Experiment Operator Station

ESIG-3000 ............................................ Evans & Sutherland Image Generator- 3000

FAA ....................................................... Federal Aviation Administration

FANS..................................................... Future Air Navigation System

FCS ....................................................... Flight Control System

FMC ...................................................... Flight Management Computers

FMS ...................................................... Flight Management System

FTE ....................................................... Flight Technical Error

GFC ...................................................... Guidance Flight Control

GNSSU ................................................. Global Navigation Satellite Sensor Unit

GPS ...................................................... Global Positioning System

GTRS .................................................... Generic Tiltrotor System

HDD ...................................................... Head-Down Display

HelMEE ................................................. Helicopter Maneuver Envelope Enhancement

HSCT .................................................... High Speed Civil Transport

HSR ...................................................... High Speed Research

HUD ...................................................... Head-Up Display

IATA....................................................... International Air Transport Association

IBM........................................................ International Business Machines

IC .......................................................... Initial Conditions
Aeronautical Test and Simulation Division 47

List of Acronyms CVSRF Projects

ICAB...................................................... Interchangeable Cab

ICAO ..................................................... International Civil Aeronautics Organization

ICH ........................................................ Improved Cargo Helicopter

IHADSS................................................. Integrated Helmet Display and Sighting System

ILCA ...................................................... Integrated Lower Control Actuators

ILS/MLS ................................................ Instrument Landing System/Microwave Landing System

IMC ....................................................... Instrument Meteorological Conditions

I/O ......................................................... Input/ output

IQS ........................................................ International Qualification Standard

KSC....................................................... Kennedey Space Center

LNAV ..................................................... Lateral Navigation

MAWEA................................................. Modular Avionics and Warning Electronics Assembly

MCDU ................................................... Multifunctional Control Display Unit

MCP ...................................................... Mode Control Panel

MEDS.................................................... Multifunction Electronic Display System

MIDI ...................................................... Musical Instrument Digital Interface

MIT ........................................................ Massachusettes Institute of Technology

NASA .................................................... National Aeronautics & Space Administration

NCA ...................................................... Neuro Controlled Aircraft

NOE ...................................................... Nap-of-the-earth

OEI ........................................................ One Engine Inoperative

PCA....................................................... Propulsion Controlled Aircraft

PDG ...................................................... Pilot Directed Guidance

PDGTRS ............................................... Preliminary Design Generic Tiltrotor Simulation

PIO ........................................................ Pilot-Induced Oscillation

PRM ...................................................... Precision Runway Monitor

R-cab .................................................... Rotorcraft Cab

RC ......................................................... Rate Command

RNP ...................................................... Required Navigation Performance

RTA ....................................................... Required Time of Arrival

RTF ....................................................... Return To Flight

S-cab..................................................... Space Shuttle (interchangeable) Cab

SATCOM ............................................... Satellite-based Communications

SCAS .................................................... Stability & Control Augmentation System

SFO....................................................... San Francisco International Airport

SGI ........................................................ Silicon Graphics Incorporated

SHCT .................................................... Short Haul Civil Tiltrotor

SimLab .................................................. Simulation Laboratories (part of the AO Division)

SSV ....................................................... Space Shuttle Vehicle

STA ....................................................... Shuttle Training Aircraft

STOVL .................................................. Short TakeOff and Vertical Landing

TAEM .................................................... Terminal Area Energy Management

TAP ....................................................... Terminal Area Productivity

TCAS .................................................... Traffic Alerting and Collision Avoidance System

TERPS .................................................. Terminal Procedures

TIFS ...................................................... Total In-Flight Simulator

TRACON ............................................... Terminal Radar Control

TRC....................................................... Translational Rate Command

VFR ....................................................... Visual Flight Rules

VLAB ..................................................... Virtual Laboratory

VMS ...................................................... Vertical Motion Simulator

VNAV .................................................... Vertical Navigation

XV-15 .................................................... Experimental Vehicle 15, a tiltrotor

YCH-47 ................................................. 1961 “Chinook”
48 Aeronautical Test and Simulation Division

A very brief description of the Aeronautical

Test and Simulation Division facilities follows.

More detailed information can be found on the

world wide web at:

http://www.simlabs.arc.nasa.gov

Boeing 747-400 Simulator

This simulator represents a cockpit of one of

the most sophisticated airplanes flying today.

The simulator is equipped with programmable

flight displays that can be easily modified to

create displays aimed at enhancing flight crew

situational awareness and thus improving

systems safety. The simulator also has a fully

digital control loading system, a six degree-offreedom motion system, a digital sound and

aural cues system and a fully integrated

autoflight system which provides aircraft guidance and control. It is also equipped with a

weather radar system simulation. The visual

display system is a Flight Safety International

driven by a VITAL VIIIi. The host computer

driving the simulator is one of the IBM 6000

series of computers utilizing IBM’s reduced

instruction set computer (RISC) Technology. An

additional IBM 6000 computer is provided solely

for the purpose of collecting and storing data in

support of experiment studies.

The 747-400 simulator provides all modes of

airplane operation from cockpit preflight to

parking and shutdown at destination. The

simulator flight crew compartment is a fully

detailed replica of a current airline cockpit. All

instruments, controls and switches operate as

they do in the aircraft. All functional systems of

the aircraft are simulated in accordance with

aircraft data. To ensure simulator fidelity the

747-400 simulator is maintained to the highest

possible level of certification for airplane simulators as established by the Federal Aviation

Administration (FAA). This ensures credibility of

the results of research programs conducted in

the simulator.

Advanced Concepts Flight Simulator

This unique research tool simulates a generic

commercial transport aircraft employing many

advanced flight systems as well as features

existing in the newest aircraft being built today.

The ACFS generic aircraft was formulated and

sized on the basis of projected user needs

beyond the year 2000. Among its advanced

flight systems, the ACFS includes touch sensitive electronic checklists, advanced graphical

flight displays, aircraft systems schematics, a

flight management system, and a spatialized

aural warning and communications system. In

addition, the ACFS utilizes side stick controllers

for aircraft control in the pitch and roll axes.

ACFS is mounted atop a six degree-of-freedom

motion system.

The ACFS utilizes SGI computers for the host

system as well as graphical flight displays. The

ACFS uses visual generation and presentation

systems that are the same as the 747-400

simulator’s. These scenes depict specific airports and their surroundings as viewed at dusk,

twilight, or night from the cockpit.

Air Traffic Control Simulator

The Air Traffic Control (ATC) environment is a

significant contributor to pilot workload and,

therefore, to the performance of crews in flight.

Full-mission simulation is greatly affected by the

realism with which the ATC environment is

modeled. From the crew’s standpoint, this

environment consists of dynamically changing

verbal or data-link messages, some addressed

to or generated by other aircraft flying in the

immediate vicinity.

The CVSRF ATC simulator is capable of

operating in three modes: stand-alone, without

participation by the rest of the facility; single-cab

mode, with either advanced or conventional cab

participating in the study; and dual-cab mode,

with both cabs participating.
Aeronautical Test and Simulation Division 49

Appendix 1

Vertical Motion Simulator Complex

The VMS is a critical national resource supporting the country’s most sophisticated aerospace R&D programs. The VMS complex offers

three laboratories fully capable of supporting

research. The dynamic and flexible research

environment lends itself readily to simulation

studies involving controls, guidance, displays,

automation, handling qualities, flight deck

systems, and accident/incident investigations.

Other areas of research include the development of new techniques and technologies for

simulation and defining requirements for training

and research simulators.

The VMS’ large amplitude motion system is

capable of 60 feet of vertical travel and 40 feet

of lateral or longitudinal travel. It has six independent degrees of freedom and is capable of

maximum performance in all axes simultaneously. Motion base operational efficiency is

enhanced by the interchangeable cab (ICAB)

system. Each of the five simulation cockpits is

customized, configured and tested at a fixedbase development station and then either used

in place for a fixed base simulation or moved on

to the motion platform.

Digital image generators provide full color

daylight scenes and include 6 channels, multiple

eye points, and a chase plane point of view.

The VMS simulation lab maintains a large

inventory of customizable visual scenes with a

unique in-house capability to design, develop

and modify these databases. Real-time aircraft

status information can be displayed to both pilot

and researcher through a wide variety of analog

instruments, and Head-Up, Head-Down or

Helmet-Mounted Displays.
50 Aeronautical Test and Simulation Division
Aeronautical Test and Simulation Division 51

Notes
For additional information, please contact

A. D. Jones

Associate Chief-Simulations

Aeronautical Test & Simulation Division

(650) 604-5928

E-mail: adjones@mail.arc.nasa.gov