TARGET GENERATION FACILITY

TO

FLIGHT SIMULATOR\
INTERFACE CONTROL DOCUMENT

(FINAL)

Prepared for:

Dan Warburton

ACB-860

Simulation Group (ACB-860)

Real & Virtual Division (ACB-800)

Federal Aviation Administration

William J. Hughes Technical Center

Atlantic City, NJ 08405

Prepared by:

System Resources Corporation

MAY 15, 1995

**This updated version of the Target Generation Facility to Flight
Simulator Interface Control Document has been revised from the original
document that SIR/AS& T TGF and Documentation personnel researched,
wrote and produced on August 24, 1992.**

**NOTE: Comments and updates to this document should be submitted to
ACT-510. See Appendix F, Update Form for exact procedure.**

**LEVEL DATE COMMENTS**

-   August 24, 1992 New Document

-   October 20, 1993 Redesigned data formats.

-   February 14, 1994 Added Pressure Altitude field to site data.

-   February 16, 1994 Added two flight simulators

-   March 11, 1994 Added climb/descend rate to site data. Will allow
    either \< CR\> or \< LF\> as terminated for site data.

-   May 2, 1994 Changed sim time to be GMT at site.

-   May 15, 1995 1) Changes to Aircraft Update Message (AUM), (Table
    4-2) 2) Misc. corrections and updates to the present

TABLE OF CONTENTS

1\. INTRODUCTION [1](#introduction)

1.1 PURPOSE [1](#purpose)

1.2 ORGANIZATION [1](#organization)

2\. FLIGHT SIMULATOR OVERVIEW [2](#flight-simulator-overview)

3\. HARDWARE [3](#hardware)

3.1 TARGET GENERATION FACILITY [3](#target-generation-facility)

3.1.1 Simulation Pilot Subsystem [3](#simulation-pilot-subsystem)

3.1.2 Target Generation Subsystem [4](#target-generation-subsystem)

3.1.3 Development and Support Subsystem
[5](#development-and-support-subsystem)

3.2 FLIGHT SIMULATOR HARDWARE [6](#flight-simulator-hardware)

3.3 COMMUNICATION CHANNEL [7](#communication-channel)

3.3.1 Communication Equipment [7](#communication-equipment)

3.3.2 Terminal Server [7](#terminal-server)

3.3.3 Router [7](#router)

4\. DATA INTERFACE [11](#data-interface)

4.1 MESSAGE FLOW [11](#message-flow)

4.2 DATA DESCRIPTION [12](#data-description)

4.3 TARGET GENERATION TO FLIGHT SIMULATOR MESSAGE
[13](#target-generation-to-flight-simulator-message)

4.3.1 Sim-Time-Status Message [13](#sim-time-status-message)

4.3.1.1 Data Field 1 - Start of Message (START)
[14](#data-field-1---start-of-message-start)

4.3.1.2 Field Separator [14](#field-separator)

4.3.1.3 Data Field 2 - Simulation Time (SIM-TIME)
[14](#data-field-2---simulation-time-sim-time)

4.3.1.4 Data Field 3 - Simulation Status (SIM-STATUS)
[14](#data-field-3---simulation-status-sim-status)

4.3.1.5 Data Field 4 - Aircraft Identification (ACID)
[14](#data-field-4---aircraft-identification-acid)

4.3.1.6 Data Field 5 - Beacon Code (BEACON)
[14](#data-field-5---beacon-code-beacon)

4.3.1.7 Data Field 6 - Frequency (FRQUENCY)
[15](#data-field-6---frequency-frquency)

4.3.1.8 Data Field 7 - End of Message (END)
[15](#data-field-7---end-of-message-end)

4.4 FLIGHT SIMULATOR TO TGF [16](#flight-simulator-to-tgf)

4.4.1 Aircraft-Update Message [16](#aircraft-update-message)

4.4.1.1 Data Field 1 - Start of Message (START)
[17](#data-field-1---start-of-message-start-1)

4.4.1.2 Data Field 2 - Aircraft Identification (ACID)
[17](#data-field-2---aircraft-identification-acid)

4.4.1.3 Data Field 3 - Beacon Code (BEACON)
[17](#data-field-3---beacon-code-beacon)

4.4.1.4 Data Field 4 - Latitude (LATITUDE)
[17](#data-field-4---latitude-latitude)

4.4.1.5 Data Field 5 - Longitude (LONGITUDE)
[18](#data-field-5---longitude-longitude)

4.4.1.6 Data Field 6 - Altitude (ALTITUDE)
[18](#data-field-6---altitude-altitude)

4.4.1.7 Data Field 7 - Altitude (PRESSURE)
[18](#data-field-7---altitude-pressure)

4.4.1.8 Data Field 8 - Climb/Descent Rate (CLIMB-DESC-RATE)
[18](#data-field-8---climbdescent-rate-climb-desc-rate)

4.4.1.9 Data Field 9 - Status (STATUS)
[19](#data-field-9---status-status)

4.4.1.10 Data Field 10 - Heading (HEADING)
[19](#data-field-10---heading-heading)

4.4.1.11 Data Field 11 - Indicated Air Speed (IND-SPEED)
[19](#data-field-11---indicated-air-speed-ind-speed)

4.4.1.12 Data Field 12 - True Air Speed (TRUE-SPEED)
[19](#data-field-12---true-air-speed-true-speed)

4.4.1.13 Data Field 13 - Transponder [19](#data-field-13---transponder)

4.4.1.14 Data Field 14 - Frequency (FREQUENCY)
[20](#data-field-14---frequency-frequency)

4.4.1.15 Data Field 15 - Engine Pressure Ratio (EPR)
[20](#data-field-15---engine-pressure-ratio-epr)

4.4.1.16 Data Field 16 - Simulation Time (SIM-TIME)
[20](#data-field-16---simulation-time-sim-time)

4.4.1.17 Data Field 17 - Message Counter
[20](#data-field-17---message-counter)

4.4.1.18 Data Field 18 - End of Message (END)
[20](#data-field-18---end-of-message-end)

5\. TCAS filter for TGF [21](#tcas-filter-for-tgf)

5.1 INTRODUCTION. [21](#introduction.)

5.2 CONSTRAINTS. [21](#constraints.)

5.3 MESSAGE FORMATS. [22](#message-formats.)

5.3.1 DATA REQUIREMENTS. [22](#data-requirements.)

5.3.1.1 Target Velocity and Track. [22](#target-velocity-and-track.)

5.3.1.2 Altitude and Altitude Rate. [22](#altitude-and-altitude-rate.)

5.3.1.3 Aircraft ID (ACID). [23](#aircraft-id-acid.)

5.3.1.4 Time. [23](#time.)

5.3.2 MESSAGE FORMATS. [23](#message-formats.-1)

5.3.3 TRANSMISSION RATE [25](#transmission-rate)

5.4 FILTERING ALGORITHMS. [25](#filtering-algorithms.)

5.4.1 DATA REQUIREMENTS. [25](#data-requirements.-1)

5.4.1.1 Coarse Filter. [25](#coarse-filter.)

5.4.1.2 Fine Filter. [26](#fine-filter.)

5.4.2 IMPLICATIONS OF THE FILTERS [27](#implications-of-the-filters)

5.4.3 COMPUTATIONAL SUGGESTIONS. [28](#computational-suggestions.)

APPENDIX A - ACRONYM LIST A [29](#appendix-a---acronym-list-a)

APPENDIX B - ORGANIZATIONAL RESPONSIBILITY
[30](#appendix-b---organizational-responsibility)

APPENDIX C - FLIGHT SIMULATORS [31](#appendix-c---flight-simulators)

APPENDIX D - FLIGHT SIMULATOR [32](#appendix-d---flight-simulator)

APPENDIX E - SAMPLE DATA [35](#appendix-e---sample-data)

APPENDIX F - UPDATE FORM [37](#appendix-f---update-form)

LIST OF ILLUSTRATIONS

[Figure 2-1 Flight Simulator Laboratory Configuration
2-2](../F2-1-FSLC.GIF)\
[Figure 3-1 TGF Subsystems 3-2](../F3-1-TGFS.GIF) [\
]{.underline}[Figure 3-2 TGF Configuration 3-4](../F3-2-TGFC.GIF)\
[Figure 3-3 Communication Equipment 3-6](../F3-3-CE.GIF)\
[Figure 3-4 Flight Simulator Configuration 3-7](../F3-4-FSC.GIF)\
[Figure 3-5 TGF to Flight Simulator Network 3-8](../F3-5-TGFFSN.GIF)\
[Figure 4-1 Message Flow Diagram 4-2](../F4-1-MFD.GIF)

LIST OF TABLES

[Table 4-1 SIM-TIME STATUS MESSAGE 4-3](../t4-1-STSM.GIF)\
[Table 4-2 AIRCRAFT UPDATE MESSAGE 4-6](../t4-2-UM.GIF)

# 1. INTRODUCTION

The Target Generation Facility (TGF) was developed primarily to perform
Operational Test and Evaluation (OT& E) for all phases of the Advanced
Automation System (AAS). Additionally, TGF supports the testing of Air
Traffic Control (ATC) systems. This testing frequently necessitates
interfacing with flight simulators.

## 1.1 PURPOSE

The TGF to Flight Simulator Interface Control Document (ICD) defines the
interface between the Target Generation Facility and flight simulators.
This ICD describes the requirements of the communication interface
between these systems. New simulators should conform with the data
interface standard which is described in Section 4.

## 1.2 ORGANIZATION

The TGF at the Federal Aviation Administration Technical Center (FAA
Technical Center) is managed by theSystem Simulation Support Branch,
ACT-510, of the Aviation Simulation and Human Factors Division, ACT-500.
Responsibility for the flight simulators rests with the individual
sites.

# 2. FLIGHT SIMULATOR OVERVIEW

The laboratory configuration for supporting the flight simulators, which
is shown in Figure 2-1, Flight Simulator Laboratory Configuration,
consists primarily of the flight simulators, the Target Generation
Facility (TGF) and the Air Traffic Control (ATC) laboratories. The
following paragraphs describe the operational flow of this laboratory
configuration along with other major interfaces. Initial communication
with the flight simulators is established utilizing a SUN workstation.
The flight simulators, listed in Appendix C, provide the aircraft data
and voice communication to the ATC laboratories. The aircraft data is
reformatted by the communication concentrator within the TGF. The TGF
then provides the surveillance target data at the required message
output rates (e.g. 2.4 seconds, 1 second) and formats necessary to
accurately simulate the radar system. The messages output from TGF are
sent to the appropriate controller displays in the ATC laboratory. In a
typical use of a flight simulator, a scenario is executed using both
flight simulators and targets generated by the TGF. The flight
simulators are flown by actual pilots whereas the TGF aircraft are
\"flown\" by the Simulation Pilot Operators (SPOs) in the TGF
laboratory. During the simulation, both the Simulation Pilot Operators
and actual pilots respond to commands issued from the air traffic
controllers under normal and \"blunder\" situations. Analysis is
primarily focused on the reaction times and responses between the actual
pilots and ATCs as well as the performance of the flight simulator
aircraft. The remainder of this document will focus on the hardware and
software interface from the TGF to the Flight Simulators.

![](media/image1.png){width="5.952083333333333in"
height="3.707638888888889in"}

Figure 2-1 Flight Simulator Laboratory Configuration

# 3. HARDWARE

The following paragraphs describe the TGF hardware including the
communication concentrator, the flight simulator hardware and the
communication channel.

## 3.1 TARGET GENERATION FACILITY

The TGF hardware has been allocated into three subsystems as shown in
Figure 3-1, TGF Subsystems. These subsystems are Simulation Pilot,
Target Generation, and Development and Support.

### 3.1.1 Simulation Pilot Subsystem

The Simulation Pilot Subsystem consists of both the Simulation Pilot
Workstations (SPWs) and the Exercise Control Workstations (ECWs). Each
workstation consists of an 80386-based personal computer running under
MS-DOS. Pairs of SPWs are mounted inside a customized table which
contains a Denro communication system that provides an interface with
Air Traffic Controllers. The Simulation Pilot Operators use the SPWs to
\"fly\" the simulated aircraft and command them in accordance with air
traffic controller instructions. The Exercise Control Operators (ECOs)
use the ECWs to control the execution of the exercise.

### 3.1.2 Target Generation Subsystem

The Target Generation Subsystem consists of both a Target Generation
Chassis and an External Interface Chassis. Each chassis is based upon a
VME architecture employing 68030-based processor boards. This subsystem
runs under a real time operating system, VxWorks, and executes
application programs written in the C language.

![](media/image2.png){width="6.426388888888889in"
height="4.288888888888889in"}

Figure 3-1 TGF Subsystems

The Target Generation Subsystem performs all modeling within the TGF and
correlates dynamic data such as aircraft state vectors, radar
performance, weather vectors and states, with known flight plan and
adaptation data. In addition, this subsystem is responsible for creating
the exact form and content of the digitized radar messages sent to the
ATC system under test.

### 3.1.3 Development and Support Subsystem

The Development and Support Subsystem is based on a SUN architecture
that employs a SUN 3/470 as a file server, a set of peripherals, and SUN
3/80 diskless computers as the Development and Support Workstations
(DSWs). The Development and Support subsystem uses SunOS UNIX as the
operating system. The Development and Support Subsystem provides the
basic pre-exercise scenario preparation and validation capabilities for
the Scenario Development Analyst (SDA), the post-exercise data reduction
and analysis capabilities for the Data Reduction Analyst (DRA), and the
resources allocation and monitoring capabilities for the System Monitor
Operator (SMO). In addition, this subsystem provides the capabilities
necessary to maintain and/or enhance the TGF software. A full range of
software development tools, which permit access to the source and object
files, is provided via this subsystem. Connectivity between the SUN
3/80s is provided by a Thick-Net Ethernet LAN, while a Thin-Net Ethernet
LAN provides communications to the other two TGF subsystems. The TGF
Configuration, Figure 3-2, illustrates the interconnectivity of the
three subsystems. In order to interface with the flight simulators, the
Development and Support Subsystem has been upgraded to include a
communication concentrator which consists of a SUN SPARC workstation
plus the software necessary to reformat the flight simulator data prior
to being processed by the target generator.

![](media/image3.png){width="6.813194444444444in" height="3.8in"}

##  

## 3.2 FLIGHT SIMULATOR HARDWARE

The flight simulator hardware consists of a unique flight simulator for
a particular aircraft. The types and locations of the current flight
simulators interfacing with TGF are listed in Appendix C.

![](media/image4.png){width="7.106944444444444in"
height="4.486805555555556in"}

## 3.3 COMMUNICATION CHANNEL

The communication channel consists of communication equipment, a
terminal server, and a router.

### 3.3.1 Communication Equipment

As illustrated in Figure 3-3,the communication equipment consists of the
T1 channel bank, the FTS2000 Digital Access Cross-Connect Switch (DACS),
and a set of multiplexors. Each flight simulator has two voice lines and
two data lines all of which operate at 9600 bps. These four lines are
fed to a multiplexor that combines all voice and data communication into
a single 56 Kb dedicated line. Each 56 Kb line, one per flight
simulator, is then fed to an FTS2000 DACS. Here, the DACS combines all
of the 56 Kb lines into a single T1 (1.544 Mbps) line to the FAA
Technical Center. At the FAA Technical Center, the T1 line enters a T1
channel bank which separates the communication for each flight simulator
back into 56 Kb lines, through a multiplexor (decoder), and back to two
voice and two data lines at 9600 bps. The two voice lines go to the ERCE
which will route the signal to the appropriate laboratory for the air
traffic controllers. One data line is routed to the CISCO terminal
server and the other data line is reserved for future datalink.

### 3.3.2 Terminal Server

The CISCO terminal server is connected to TGF via Ethernet and utilizes
eight asynchronous ports for communication with the flight simulators.
The Flight Simulator Configuration, Figure 3-4,illustrates the
connectivity of the terminal server, the communication equipment and the
current flight simulators interfacing with TGF.

### 3.3.3 Router

The router networks the TGF with the flight simulators using standard
Ethernet cabling and operates with the Transmission Control
Program/Internet Protocol (TCP/IP) standard. The TGF to Flight Simulator
Network Diagram, Figure 3-5,presents a graphic illustration of the
network connectivity between the flight simulators and the TGF. The
format of the flight simulator data and additional software issues are
presented in the following section.

![](media/image5.png){width="6.370138888888889in"
height="5.288194444444445in"}

Figure 3-3 Communication Equipment

![](media/image6.png){width="6.410416666666666in"
height="5.5256944444444445in"}

Figure 3-4 Flight Simulator Configuration

![](media/image7.png){width="6.666666666666667in" height="5.45625in"}

Figure 3-5 TGF to Flight Simulator Network

# 4. DATA INTERFACE

This section describes the data interface standard between the TGF and
the flight simulators.

## 4.1 MESSAGE FLOW

\>The message flow between the TGF and the flight simulators is shown in
Figure 4-1, Message Flow Diagram.

![](media/image8.png){width="6.377083333333333in"
height="4.2340277777777775in"}

## 4.2 DATA DESCRIPTION

The flight simulator generates messages reflecting altitude, switch
status, and position. Each message is a maximum of 512 bytes
(expandable) long. The TGF generates messages which reflect conditions
of TGF simulation that would affect the Flight Simulator and the TGF
simulation time. The Flight Simulator Data, Appendix E, provides some
messages recorded during a typical flight simulator simulation exercise.

![](media/image8.png){width="6.625in" height="3.498611111111111in"}

Figure 4-1 Message Flow Diagram

##  

## 4.3 TARGET GENERATION TO FLIGHT SIMULATOR MESSAGE

### 4.3.1 Sim-Time-Status Message

The Sim-Time-Status Message notifies the Flight Simulator of the
simulation time each second. This message is used to achieve final
coordination between the Flight Simulator and Air Traffic Control. Table
4-1 presents the format of the Sim-Time-Status Message.

**Table 4-1 SIM-TIME STATUS MESSAGE**

+--------+-------------------+-----------+----------------+----------+
| FIELD  | FIELD             | LENGTH    | FORMAT         | VALUE    |
|        |                   |           |                |          |
| NO.    | NAME              | (Byte)    |                |          |
+--------+-------------------+-----------+----------------+----------+
| **1**  | **START**         | **3**     | **\'%NN\'**    | **\      |
|        |                   |           |                | '%09\'** |
+--------+-------------------+-----------+----------------+----------+
|        | **FIELD           | **1**     | **\' \'**      |          |
|        | SEPARATOR**       |           |                |          |
+--------+-------------------+-----------+----------------+----------+
| **2**  | **SIM-TIME**      | **8**     | **             |          |
|        |                   |           | \'HH:MM:SS\'** |          |
+--------+-------------------+-----------+----------------+----------+
|        | **FIELD           | **1**     | **\' \'**      |          |
|        | SEPARATOR**       |           |                |          |
+--------+-------------------+-----------+----------------+----------+
| **3**  | **SIM-STATUS**    | **4**     | **\'AAAA\'**   | **\'T    |
|        |                   |           |                | ERM\',** |
|        |                   |           |                |          |
|        |                   |           |                | **\'     |
|        |                   |           |                | RUN\',   |
|        |                   |           |                | or**     |
|        |                   |           |                |          |
|        |                   |           |                | **\'     |
|        |                   |           |                | FREZ\'** |
+--------+-------------------+-----------+----------------+----------+
|        | **FIELD           | **1**     | **\' \'**      |          |
|        | SEPARATOR**       |           |                |          |
+--------+-------------------+-----------+----------------+----------+
| **4**  | **ACID**          | **7**     | *              |          |
|        |                   |           | *\'AAAAAAA\'** |          |
+--------+-------------------+-----------+----------------+----------+
|        | **FIELD           | **1**     | **\' \'**      |          |
|        | SEPARATOR**       |           |                |          |
+--------+-------------------+-----------+----------------+----------+
| **5**  | **BEACON**        | **4**     | **\'NNNN\'**   | *        |
|        |                   |           |                | *OCTAL** |
+--------+-------------------+-----------+----------------+----------+
|        | **FIELD           | **1**     | **\' \'**      |          |
|        | SEPARATOR**       |           |                |          |
+--------+-------------------+-----------+----------------+----------+
| **6**  | **FREQUENCY**     | **7**     | *              |          |
|        |                   |           | *\'NNN.NNN\'** |          |
+--------+-------------------+-----------+----------------+----------+
| **7**  | **END**           | **2**     | **\'0D0A\'**   | **ASCII  |
|        |                   |           |                | CR/LF**  |
+--------+-------------------+-----------+----------------+----------+

####  

#### 4.3.1.1 Data Field 1 - Start of Message (START)

The Start of Message consists of a 3-byte ASCII character field
containing a \'%\' followed by a zero and a nine for unique message
identification.

#### 4.3.1.2 Field Separator

A 1-byte ASCII space character is provided between each field to assist
in the readability of this data on the cockpit simulator site terminals.

#### 4.3.1.3 Data Field 2 - Simulation Time (SIM-TIME)

The Simulation Time Identification of the TGF System consists of an
8-byte ASCII character field representing the current simulation time in
hours, minutes, and seconds. The hours field is based on the 00- 24
24-hour format (\"military time\").

Format: \'HH:MM:SS\'

Example: \'00:12:35\'

This field is used to synchronize the time among all of the sites.

#### 4.3.1.4 Data Field 3 - Simulation Status (SIM-STATUS)

The Status of the TGF experiment indicates the current state of the
simulation. It consists of a 4-byte ASCII character field with the
values \'TERM\', \' RUN\', or \'FREZ\'.

#### 4.3.1.5 Data Field 4 - Aircraft Identification (ACID)

The Aircraft Identification consists of a left-justified and
blank-filled aircraft ID in a 7-byte ASCII character field. This field
is provided as information for the simulator sites only and may be blank
when data is not available.

Format: \'AAAAAAA\'

Example: \'DAL58 \'

#### 4.3.1.6 Data Field 5 - Beacon Code (BEACON)

The Beacon Code consists of a right-justified and zero-filled octal
integer beacon code in a 4-byte ASCII character field. This is also
called the Transponder Code. This field is provided as information for
the simulator sites only and may be blank when data is not available.

Format: \'NNNN\'

Example: \'0473\'

#### 4.3.1.7 Data Field 6 - Frequency (FRQUENCY)

The Frequency consists of a 7-byte ASCII character field representing
the communication frequency. This field is provided as information for
the simulator sites only and may be blank when data is not available.

Format: \'NNN.NNN\'

Example: \'135.75 \'

#### 4.3.1.8 Data Field 7 - End of Message (END)

The End of Message, which must be present to indicate the end of each
message, consists of two ASCII bytes with values \'0D0A\' expressed in
hexadecimal notation. This is the ASCII carriage return/line feed
combination (CR/LF).

##  

## 4.4 FLIGHT SIMULATOR TO TGF

### 4.4.1 Aircraft-Update Message

The Aircraft-Update Message sends new aircraft positioning information
to the TGF for processing at the rate of at least once per second. The
preferred update rate is once every half-second. The TGF displays the
new Flight Simulator position.

Table 4-2 presents the format of the Aircraft Update Message.

**Table 4-2 AIRCRAFT UPDATE MESSAGE**

+--------+-------------------+----------+----------------+-----------+
| FIELD\ | FIELD NAME        | LENGTH   | FORMAT         | VALUE     |
| NO.    |                   |          |                |           |
|        |                   | (Byte)   |                |           |
+--------+-------------------+----------+----------------+-----------+
| **1**  | **START**         | **3**    | **\'%NN\'**    | **        |
|        |                   |          |                | \'%10\'** |
+--------+-------------------+----------+----------------+-----------+
| **2**  | **ACID**          | **7**    | *              |           |
|        |                   |          | *\'AAAAAAA\'** |           |
+--------+-------------------+----------+----------------+-----------+
| **3**  | **BEACON**        | **4**    | **\'NNNN\'**   | **OCTAL** |
+--------+-------------------+----------+----------------+-----------+
| **4**  | **LATITUDE**      | **10**   | **\'           | **        |
|        |                   |          | ±NN.NNNNNN\'** | DEGREES** |
+--------+-------------------+----------+----------------+-----------+
| **5**  | **LONGITUDE**     | **11**   | **\'±          | **        |
|        |                   |          | NNN.NNNNNN\'** | DEGREES** |
+--------+-------------------+----------+----------------+-----------+
| **6**  | **ALTITUDE**      | **6**    | **\'NNNNNN\'** | **FEET**  |
+--------+-------------------+----------+----------------+-----------+
| **7**  | **ALTITUDE        | **6**    | **\'NNNNNN\'** | **FEET**  |
|        | (PRESSURE)**      |          |                |           |
+--------+-------------------+----------+----------------+-----------+
| **8**  | **                | **5**    | **\'±NNNN\'**  | *         |
|        | CLIMB-DESC-RATE** |          |                | *FT/SEC** |
+--------+-------------------+----------+----------------+-----------+
| **9**  | **STATUS**        | **1**    | **\'I\',       | **\'IN\', |
|        |                   |          | \'O\', \'T\'** | \'OUT\'** |
|        |                   |          |                |           |
|        |                   |          |                | **or      |
|        |                   |          |                | \         |
|        |                   |          |                | 'TERM\'** |
+--------+-------------------+----------+----------------+-----------+
| **10** | **HEADING**       | **6**    | **\'NNN.NN\'** | **        |
|        |                   |          |                | DEGREES** |
+--------+-------------------+----------+----------------+-----------+
| **11** | **IND-SPEED**     | **6**    | **\'NNNN.N\'** | **NM/HR** |
+--------+-------------------+----------+----------------+-----------+
| **12** | **TRUE-SPEED**    | **6**    | **\'NNNN.N\'** | **NM/HR** |
+--------+-------------------+----------+----------------+-----------+
| **13** | **IDENT**         | **1**    | **\'I\'**      | **\'I\'   |
|        |                   |          |                | or \'     |
|        |                   |          |                | \'**      |
+--------+-------------------+----------+----------------+-----------+
| **14** | **FREQUENCY**     | **7**    | *              |           |
|        |                   |          | *\'NNN.NNN\'** |           |
+--------+-------------------+----------+----------------+-----------+
| **15** | **EPR**           | **4**    | **\'N.NN\'**   |           |
+--------+-------------------+----------+----------------+-----------+
| **16** | **SIM-TIME**      | **12**   | **\'HH         |           |
|        |                   |          | :MM:SS.SSS\'** |           |
+--------+-------------------+----------+----------------+-----------+
| **17** | **MESSAGE         | **6**    | **\'NNNNNN\'** | **        |
|        | COUNTER**         |          |                | INTEGER** |
+--------+-------------------+----------+----------------+-----------+
| **18** | **END**           | **1**    | **\'0D\' or    | **ASCII   |
|        |                   |          | \'0A\'**       | CR/LF**   |
+--------+-------------------+----------+----------------+-----------+

#### 

#### 

#### 4.4.1.1 Data Field 1 - Start of Message (START)

The Start of Message consists of a 3-byte ASCII character field
containing \'%\', followed by a one and a zero for unique message
identification.

#### 4.4.1.2 Data Field 2 - Aircraft Identification (ACID)

The Aircraft Identification consists of a left-justified and blank
filled aircraft ID in a 7-byte ASCII character field.

Format: \'AAAAAAA\'

Example: \'DAL58 \'

This field is optional and provided for readability and debugging.

#### 4.4.1.3 Data Field 3 - Beacon Code (BEACON)

The Beacon Code Identification consists of a right-justified and
zero-filled octal integer beacon code in a 4-byte ASCII character field.
This is also called the Transponder Code.

Format: \'NNNN\'

Example: \'0473\'

Refer to Appendix D for usage of this field.

#### 4.4.1.4 Data Field 4 - Latitude (LATITUDE)

The Latitude consists of a 10-byte decimal ASCII character field
containing a fixed-point, blank-filled real value representing degrees,
preceded by either \'+\', \'-\', or \' \', where \'+\' or \' \'
indicates Northern Hemisphere and \'-\' indicates Southern Hemisphere.

Format: \'±NN.NNNNNN\'

Example: \'+38.296734\'

#### 4.4.1.5 Data Field 5 - Longitude (LONGITUDE)

The Longitude consists of a 11-byte decimal ASCII character field
containing a fixed-point, blank-filled real value representing degrees
preceded by either \'+\', \'-\', or \' \', where \'+\' or \' \'
indicates Western Hemisphere and \'-\' indicates Eastern Hemisphere.

Format: \'±NNN.NNNNNN\'

Example: \'+123.567894\'

#### 4.4.1.6 Data Field 6 - Altitude (ALTITUDE)

The Altitude consists of a 6-byte ASCII character field containing a
blank-filled integer value representing feet. This field contains true
(MSL) altitude.

Format: \'NNNNNN\'

Example: \' 10000\'

#### 4.4.1.7 Data Field 7 - Altitude (PRESSURE)

The Altitude consists of a 6-byte ASCII character field containing a
blank-filled integer value representing feet. This field contains
pressure altitude.

Format: \'NNNNNN\'

Example: \' 10000\'

#### 4.4.1.8 Data Field 8 - Climb/Descent Rate (CLIMB-DESC-RATE)

The Climb/Descent Rate consists of an 5 byte ASCII character field
containing a blank filled real value representing feet per second. The
first byte can be either a \'+\', \'-\', or \' \', where \'+\' and \' \'
are positive. This is shown in the following format and example:

Format: \'±NNNN\'

Example: \' 123\'

Note: Positive values are climbs, negative ones are descents.

#### 4.4.1.9 Data Field 9 - Status (STATUS)

The status field consists of a 1-byte ASCII character field representing
cockpit status. It will determine if a simulator site has control of an
aircraft. \'O\' for out of the simulation, \'I\' for in the simulation,
or \'T\' to terminate last controlled aircraft. Refer to Appendix D for
further explanation of this field.

#### 4.4.1.10 Data Field 10 - Heading (HEADING)

The Heading consists of a 6-byte ASCII character field containing a
fixed-point, blank-filled real value representing magnetic degrees.

Format: \'NNN.NN\'

Example: \'123.56\'

#### 4.4.1.11 Data Field 11 - Indicated Air Speed (IND-SPEED)

The Indicated Air Speed consists of an 6-byte ASCII character field
containing a fixed-point, blank-filled real value representing knots
(nautical miles per hour). This is the speed displayed in the Flight
Simulator, not the speed as observed from the ground.

Format: \'NNNN.N\'

Example: \'1234.6\'

#### 4.4.1.12 Data Field 12 - True Air Speed (TRUE-SPEED)

The True Air Speed consists of an 6-byte ASCII character field
containing a fixed-point, blank-filled real value representing knots
(nautical miles per hour).

Format: \'NNNN.N\'

Example: \' 123.5\'

#### 4.4.1.13 Data Field 13 - Transponder

The transponder field consists of a 1-byte ASCII character field
representing the transponder status of the aircraft. The field will be
set to \"I\" when the pilot has pressed the IDENT button in the cockpit.
Ident implies that the transponder is transmitting. This field will be
set to \"S\" when the transponder is in standby mode and not
transmitting. Otherwise, this field is blank to indicate the transponder
is on and transmitting.

#### 4.4.1.14 Data Field 14 - Frequency (FREQUENCY)

The Frequency consists of a 7-byte ASCII character field representing
the communication frequency. The frequency must be a valid simulation
frequency or TGF will ignore it and default to zero (for no
communications).

Format: \'NNN.NNN\'

Example: \'135.75 \'

#### 4.4.1.15 Data Field 15 - Engine Pressure Ratio (EPR)

This field consists of a 4-byte ASCII character field containing a
fixed-point, zero-filled real value representing the current EPR from
the cockpit simulator. This will be used in data analysis. The EPR
should be obtained from the center, inboard engine, or multi-engine
aircraft.

Format: \'N.NN\'

Example: \'0.80\'

#### 4.4.1.16 Data Field 16 - Simulation Time (SIM-TIME)

The Simulation Time consists of an 12-byte ASCII character field
representing the current Greenwich Meridian Time (GMT) in hours,
minutes, and seconds.

Format: \'HH:MM:SS.SSS\'

Example: \'16:12:35.913\'

This field is provided for error tracking.

#### 4.4.1.17 Data Field 17 - Message Counter

The Message Counter consists of a 6-byte ASCII character field
containing a zero- or blank-filled integer value that will start at zero
at the start of a simulation and increment for each message sent. This
field will be used for recognizing lost messages.

Format: \'NNNNNN\'

Example: \' 2810\'

#### 4.4.1.18 Data Field 18 - End of Message (END)

The End of Message, which must be present to indicate the end of each
message, consists of a 1-byte ASCII character field with a value of
either hexadecimal \'0D\' (ASCII carriage return \< CR\> ) or
hexadecimal \'0A\' (ASCII line feed \< LF\> ).

# 5. TCAS filter for TGF

## 5.1 INTRODUCTION.

This document contains specifications and data formats to enable a
function to be added to the Technical Center's Target Generator Facility
(TGF) to permit traffic awareness in end-to-end airspace simulations.
The Data Link program at the Center has a requirement to display
proximate traffic in an airspace simulation to flight crews operating
flight simulators networked to the TGF. The display of proximate traffic
will be by means of aircraft images in the out-of-the-window scene of
the simulator, and by means of threat symbols on the simulator's TCAS.

Traffic in the simulation may consist of simulator operator driven
targets, or other flight simulators.

The Airborne Data Link Program at the Center is concerned with human
factors issues relating to the time spent by flight crews interacting
with Data Link clearances from air traffic control (ATC). There is an
industry concern that Data Link communications will reduce the awareness
of the airspace conditions around the aircraft, and will distract flight
crews away from visually scanning the airspace outside the aircraft. End
to end simulations have not been heretofore able to address these issues
except in limited case studies using scripted scenarios. In the
end-to-end simulations performed at the Center, the level of fidelity in
the ATC simulation implies stochastic traffic interactions and requires
that traffic information is made available on the fight deck.

## 5.2 CONSTRAINTS.

Flight Simulators are linked by means of a limited bandwidth network
that has only 9.6 kilo-bits per second transmission capability.
Therefore, the TGF must filter the larger data set to derive traffic
information that is sent to each cockpit. A two step algorithm is
proposed in this paper, consisting of a coarse filter followed by a fine
filter. This approach is thought to save computing power in the TGF by
applying the more computational intensive (fine) filter to a data set
which has been reduced by the coarse filter.

Target data must be sent to each simulator site at a rate of not less
than once per second. Simulator host computers can interpolate the
position of the target aircraft, but require a frequency of update of Hz
to minimize the error. Current thinking is that simulator host computers
can derive position and attitude of target aircraft from the track data
sent to the host. For example, from the rate of change of heading is
derived the rate of turn, and hence the required bank angle of the wings
of the aircraft image.

The last constraint applied to this function is the number of aircraft
tracks that can be sent to each simulator, owing to the limited
bandwidth of the network.

## 5.3 MESSAGE FORMATS.

### 5.3.1 DATA REQUIREMENTS.

**Table 1. shows the parameters required to generate the proper
presentation in the flight simulator visual scene and TCAS.**

TABLE 1. Aircraft State Parameters Required for Traffic Awareness at
Remote Sites

  ------------------ ------------------ ----------------- ----------------
  **Parameter**      **Units**          **Precision**     **Size**

  1\. Latitude,      dd.mm.ss           1/10 sec (ARC)    40 bits
  Longitude                                               

  2\. Aircraft ID    AAA.NNN note 1     N/A               48 bits

  3\. Time           mm.ss              1/10 sec (Time)   12 bits

  4\. Altitude       xx00 feet note 2   100 feet          12 bits

  5\. Heading        ddd                1 degree          12 bits
  ------------------ ------------------ ----------------- ----------------

**Note 1.** Aircraft ID is expressed as the flight ID, or UAL232.\
**Note 2.** Altitude is expressed in hundreds of feet.

From the data in table 1, target information can be derived as discussed
in the following paragraphs.

#### 5.3.1.1 Target Velocity and Track.

Latitude and Longitude as expressed can be smoothed using an alpha-beta
integrator at the remote site to produce first order time differences
which can be computed as velocity. Furthermore, successive reports will
produce a target track and heading. The heading parameter, shown in
table one will be used to normalize the position of the aircraft at run
startup, and also to correct the apparent heading of the target in wind
conditions.

#### 5.3.1.2 Altitude and Altitude Rate.

Successive altitude reports can be used to derive the climb or descent
rate of the target aircraft. A potential limitation in this approach is
the time lag after a vertical maneuver begins and altitude bin crossings
are evident in the data. This lag will be more pronounced at very low
maneuver rates. For example, at a 600 feet per minute rate of climb or
descent, the first bin crossing will occur after a minimum of 5 seconds
and can be lag as much as 10 seconds.

It is believed that this lag will not affect the results of an
end-to-end simulation because lower maneuver rates are not perceptible,
and are not typical of terminal area maneuvering speeds.

#### 5.3.1.3 Aircraft ID (ACID).

This parameter is used to tell the image generator at the remote site
what type of aircraft should be depicted in the window scene. Using
table lookup, the aircraft type can be associated with the correct
visual image during each run. Furthermore, the ACID is used to associate
track data with a particular aircraft.

#### 5.3.1.4 Time.

This parameter is used in all of the tracking algorithms to eliminate
the effects of transmission lag over the data network to the remote
site. At the epoch target data are extracted by the TGF, the data are
time stamped such that the tracking algorithms at the remote site can
dither the data to its correct sampling event.

#### 5.3.2 MESSAGE FORMATS.

The format for the target position data message for all targets is shown
in Figure 1.

Message ID \| No. of Records \| Record 1 \| Record 2 \| Record 3 \...\|
Record N \| Parity

1\. Message ID: Unique identifier of the TCAS record.

Length: 16 Bits

2\. No. of Records: This is the number of aircraft tracks that are
contained within the data block.

Length: 8 Bits

3\. Record Format: See Figure 2

4\. Parity: This is a Cyclic Redundancy Check character.

Length: 16 bits

Figure 1. Traffic Data Message Format

The format for each aircraft data record is shown in Figure 2.

Sequence No.\| Time\| Latitude\| Longitude\| Heading\| Altitude\| ACID\|
End of Message

1\. Sequence No: This number increments for each record for each
aircraft. Note that the sequence applies only to the particular aircraft
that this record describes. All sequence numbers increment
independently.

Note: This sequence number is required for those simulation studies
where aircraft are reintroduced into the scenario without terminating
the run. Generally the aircraft ID changes when aircraft are
re-introduced and the record would apply to a different aircraft.
However, the sequence number prevents ambiguity in the remote site
tracker.

Length: 16 Bits

2\. Time: This is the time stamp of the event that the target data is
derived from the TGF tracker.

Length: 12 Bits

3\. Latitude: This is the latitude of the target at the time stamp.

Length: 20 Bits

4\. Longitude: This is the longitude of the target at the time stamp.

Length: 20 Bits

5\. Heading: This is the current magnetic compass heading of the target
at the time stamp. The field is right justified, with zeros in the
unused bits.

Length: 12 Bits

6\. Altitude: This is the Gilliam (Gray) encoded altitude of the
aircraft in hundreds of feet, normalized to mean sea level barometric
pressure of 29.92 inches of mercury.

Length: 12 Bits.

7\. Aircraft ID: ACID. This is the flight identification of the target,
in character format. General aviation aircraft are expressed as N-xxx or
W-xxx with zeroes in the leading alpha positions in the field. If there
are more than three numbers in the tail number, the excess digits are
truncated.

Length: 48 Bits

### 5.3.3 TRANSMISSION RATE

Data shall be transmitted continuously, but updated once per second.
Total message length is 40 bits of overhead plus 140 bits per target
aircraft record. At 9600 bits per second, a maximum of 68 aircraft
records can be sent every second to each flight simulator.

## 5.4 FILTERING ALGORITHMS.

### 5.4.1 DATA REQUIREMENTS.

This ICD suggests a coarse filter to remove the bulk of traffic in the
vicinity of the flight simulator. Then a fine filter can be applied to
remove all remaining traffic that is of no consequence. The two filters
are described in the following sections.

#### 5.4.1.1 Coarse Filter. 

All aircraft within a slant range of 15 nautical miles, regardless of
relative altitude, should be associated with the flight simulator. This
range is selected because at high relative convergence rates knots, the
minimum alert time requirement for TCAS is satisfied:

**t = 3600\*R/Rdot**

**where: t=tau, TCAS alert time**

**R=range between aircraft**

**Rdot=closing rate in knots (kts)**

**at true airspeeds of 500 kts per aircraft, the closing rate is
1000kts; the minimum TCAS alert time is 45 seconds. The minimum range
gate is therefore t\*Rdot/3600=12.5 miles. The condition is satisfied.**

#### 

#### 5.4.1.2 Fine Filter.

Figure 3 shows a polar plot of the of the filter shape factor as a
function of bearing relative to the flight simulator boresight heading.
The plot is generated from the COSINE squared function. A cartioid
pattern generated from a COSINE function is plotted on the same axis to
show the effect of the second order. Note that the filter goes to zero
at 90 and 270 degrees, which eliminates all abeam traffic. Since some
abeam traffic must be included, such as would be present during parallel
approaches, a static offset is added to the filter function. The
complete filter is implemented as follows:

**R=2.5+10\*COS(f) A=Alt +/- 5000 feet**

**where f is the angle relative to a line extending along**

**the long axis**

**of the aircraft (also called the boresight angle).**

Thus any aircraft within R miles of the flight simulator, and within +/-
5000 of the simulator's altitude should be associated with the flight
simulator. The pattern shown in figure 3 is affectionately known as the
Tylenol pattern and is intended to cure headaches from too much traffic.

### 5.4.2 IMPLICATIONS OF THE FILTERS

To estimate the effect of the filter, the area enclosed by the offset
COSINE squared function must be calculated.

**2P**

**a= òRdf**

**0**

**2P**

**a=ò2.5+10\*COS2(f)df COS2(f)=1/2(1-COS(2f))**

**0**

**=2.5f+10\*\[1/2(f+0.5\*SIN(2f) evaluated at 0, 2P**

**=2.5\*P + 10\*P**

**=39.3 miles2**

If the airspace is 25 miles in diameter, and includes 120 aircraft
(randomly distributed), then the number of aircraft in the filter is
calculated as:

**Area (airspace)= P\*12.52**

**=491 miles2**

**n aircraft= 120\*39.3/491**

**=9.6 aircraft**

Thus, the effect of the filter is to reduce the number of air by a
factor of five over a slant range filter of the same maximum range as
the COSINE squared filter.

### 5.4.3 COMPUTATIONAL SUGGESTIONS.

It is suggested that TGF personnel implement the coarse range filter on
a simulator by simulator basis to build a set of targets which may be
elligible for transmission to each simulator. Next, the altitude test of
the fine filter is suggested, followed by the range test. The range test
within the fine filter requires knowlege of the bearing of each target
aircraft to the boresight bearing of each flight simulator; this is
calculated from lat/lon positions. This bearing is used as the parameter
f in the range test.

If the COSINE squared function in inconvenient for computational
purposes, the lookup table shown in Table 3 may be used. To use the
table, round the bearing to the next lowest 10 degrees and look up the
value of the COSINE squared.

# APPENDIX A - ACRONYM LIST A

**AS Advanced Automation System\
ATC Air Traffic Control bps Bit Per Second COTS
Commercial-Off-the-Shelf\
DACS Digital to Analog Converter System\
DRA Data Reduction Analyst\
DSW Development and Support Workstation\
ECO Exercise Control Operator\
ECW Exercise Control Workstation\
ERCE Ernie\'s Radio Control Equipment\
ESSF En Route System Support Facility\
EXT I/F External Interface\
FAA Technical Center Federal Aviation Administration Technical Center\
FMA Final Monitor Aids\
GASF General Aviation Simulation Facility\
GMT Greenwich Mean Time HEX Hexadecimal\
ICD Interface Control Document\
ISSS Initial Sector Suite System\
Kb Kilo Bits\
LAN Local Area Network\
LSSS Laboratory Signal Switching System\
Mbps Mega bits per second\
MS-DOS Microsoft-Disk Operating System\
MUX MUltipleXor\
OT& E Operational Test and Evaluation\
SDA Software Development Analyst\
SDL Simulation Display Laboratory\
SMO System Monitor Operator\
SPO Simulation Pilot Operator\
SPW Simulation Pilot Workstation\
SSF System Support Facility\
TCP/IP Transmission Control Protocol/Internet Protocol\
TG Target Generation\
TGF Target Generation Facility\
TSSF Terminal System Support Facility\
VME Versabus Module Europe**

# APPENDIX B - ORGANIZATIONAL RESPONSIBILITY 

**Aviation Simulation and Human Factors Division ACT-500**

**John Wiley, Division Manager 609-485-6400**

**System Simulation Support Branch ACT-510**

**Adam Greco, Branch Manager 609-485-4405\
Dan Warburton (TGF) 609-485-4480\
Richard Ozmore (Real-Time) 609-485-5368**

#  

# APPENDIX C - FLIGHT SIMULATORS 

**TYPE AGENCY LOCATION**

**B727-100 AVIA Leasing Costa Mesa, CA**

**B747-400 NASA-Ames Mountain View, CA**

**MD-88 Delta Airlines Atlanta, GA**

**MD-90 Delta Airlines Atlanta, GA**

**B767 TWA St. Louis, MO**

**B727-200 FAA Aeronautical Center Oklahoma City, OK**

**C421 FAA Technical Center Atlantic City International Airport, NJ**

**B747 (RCS) FAA Technical Center Atlantic City International Airport,
NJ**

**B747-400 United Airlines Denver, CO**

# APPENDIX D - FLIGHT SIMULATOR

**COCKPIT STATES**

**Cockpit states:**

**The cockpit simulator sites will have 2 separate fields in the
simulator data message to control the state of the target TGF
aircraft.**

**The first field is the \"status\" field. This can be set to:**

**\'O\' for out of the simulation,**

**\'I\' for in the simulation, or**

**\'T\' to terminate last controlled aircraft.**

**The second field for aircraft control is the \"beacon\" field. This
determines which TGF aircraft the simulator site will take control of.**

**The process flow for a simulator site to take over control of a TGF
aircraft is as follows:**

**The simulator site would start sending aircraft update messages with
the status field set to \'O\' (for OUT of the sim) and the beacon field
would be set to the target aircraft beacon code.**

**When the time to enter the simulation occurs, the status field would
change to \'I\' (for IN the simulation).**

**When the aircraft has landed, or otherwise is to be removed from the
simulation, the status field must be changed to \'T\' (to TERMINATE the
aircraft).**

**The above describes the process flow for an ideal setup. The following
will attempt to cover how any deviations from the ideal will be
handled.**

> **1. TGF aircraft is not in the simulation when the simulator site
> changes the status to \'I\'.**
>
> **The data being sent by the simulator site will be ignored until the
> time TGF generates the simulated aircraft to take control of. Once TGF
> starts the desired simulated aircraft, the simulator site will take
> control within the first few seconds of that aircraft\'s flight.**
>
> **2. Simulator site changes status from \'I\' to \'O\'.**
>
> **Once a site takes control of a TGF aircraft, it will not be returned
> to TGF sim-pilot control. Therefore, when the status changes to \'I\',
> the simulator site will take control of that aircraft until the
> aircraft is terminated. If the status changes back to \'O\', the
> simulator site will still retain control of the aircraft. If the
> simulator site again changes status back to \'I\', TGF will handle the
> aircraft as if the simulator site had just taken control of the
> aircraft, including using the cockpit simulator current position
> information from that time forward.**
>
> **Note that this status change between \'I\' and \'O\' can occur any
> time during the flight, and multiple times during the flight, with the
> same results each time.**
>
> **3. Simulator site changes status from \'T\' to either \'I\' or
> \'O\'.**
>
> **Once the status of \'T\' is received, the aircraft is terminated
> from the simulation and can not be retrieved. All future status
> changes for this aircraft will be ignored.**
>
> **4. Loss of data from a simulator site.**
>
> **When the loss of data occurs after the site has control of an
> aircraft, TGF will project the path of the aircraft based on the last
> valid aircraft position data (i.e., heading, speed, and altitude).
> When the loss of data is for an extended period, the target will go
> into coast for most external labs. When data is again received from
> the simulator site, this data will become the aircraft current
> position data. Note that this may cause a target \"jump\" if the loss
> of data is for a significant time.**
>
> **5. Beacon code changes when current status is \'I\'.**
>
> **This case will be considered a valid change and the current aircraft
> under control will start transmitting the new beacon code to the
> controller displays. Note that if the new beacon code is a duplicate
> of an active TGF simulated aircraft, the TGF duplicate is unchanged
> and remains under control of the sim-pilot. Therefore, the current
> aircraft under simulator site control can still be terminated, the
> status changed first to \'O\', and then the status is changed to \'I\'
> to take control of the TGF simulated aircraft with the same beacon
> code.**

# APPENDIX E - SAMPLE DATA 

> **Example Messages from TGF to Cockpit**
>
> **Sim-time Status Acid Beacon Freq**
>
> **%09 16:00:01 FREZ ACID001 1234 135.750**
>
> **%09 16:00:01 FREZ ACID001 1234 135.750**
>
> **%09 16:00:01 RUN ACID001 1234 135.750**
>
> **%09 16:00:02 RUN ACID001 1234 135.750**
>
> **%09 16:00:03 RUN ACID001 1234 135.750**
>
> **%09 16:00:04 RUN ACID001 1234 135.750**
>
> **%09 16:00:05 RUN ACID001 1234 135.750**
>
> **%09 16:00:06 RUN ACID001 1234 135.750**
>
> **%09 16:00:07 TERM ACID001 1234 135.750**
>
> **Example Messages from Cockpits to TGF**
>
> **Acid Beacon Lat Lon Alt Alt S Hdg IAS TAS I Freq EPR Sim-time
> Msg-cnt %10ACID0011234 31.818593 99.432817 22200 0O149.85 156.5 164.8
> 135.7500.8016:00:01.014 1**
>
> **%10ACID0011234 31.818593 99.432817 22200 0O149.85 156.5 164.8
> 135.7500.8016:00:01.996 2**
>
> **%10ACID0011234 31.818593 99.432817 22200 0O149.85 156.5 164.8
> 135.7500.8016:00:02.972 3**
>
> **%10ACID0011234 31.818593 99.432405 22200 0I149.85 156.5 164.8
> 135.7500.8016:00:03.948 4**
>
> **%10ACID0011234 31.818593 99.431779 22200 0I149.85 156.5 164.8
> 135.7500.8016:00:04.916 5**
>
> **%10ACID0011234 31.818593 99.431362 22200 0I149.85 156.5
> 164.8I135.7500.8016:00:05.880 6**
>
> **%10ACID0011234 31.818593 99.430944 22200 0I149.85 156.5 164.8
> 135.7500.8016:00:06.873 7**
>
> **%10ACID0011234 31.818593 99.430533 22200 0I149.85 156.5 164.8
> 135.7500.8016:00:07.895 8**
>
> **%10ACID0011234 31.818593 99.429918 22200 0I149.85 156.5 164.8
> 135.7500.8016:00:08.914 9**
>
> **%10ACID0011234 31.818593 99.429491 22200 0T149.85 156.5 164.8
> 135.7500.8016:00:09.948 10**

###  

# APPENDIX F - UPDATE FORM 

> **TO: ACT-510 (Ext. 4480)**
>
> **FROM:
> \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_
> \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\
> (Name) (Routing Symbol) (Ext.)**
>
> **DATE: \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_**
>
> **RE: TARGET GENERATION FACILITY TO FLIGHT SIMULATOR INTERFACE CONTROL
> DOCUMENT - MAY 15, 1995
> \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_**
>
> **Paragraph number, table number, figure number or appendix:**
>
> **Page number:**
>
> **Recommended change:**
>
> **NOTE: If change is extensive, please attach revised pages, or
> additions. Make changes in ink and place a bar in the margin to flag
> the change.**