National Transportation Safety Board 

 Washington, D.C. 20594 

E PLURIBUS UNUM

NATIONAL TRA SPORTATIO

N

B OARD

SAFE T Y

N

 Aircraft Accident Brief 

____________________________________________________________________________ 

Accident Number: CHI01MA006 

Aircraft and Registration: Bombardier CL-600-2B16 (CL-604), C-FTBZ 

Location: Mid-Continent Airport, Wichita, Kansas 

Date: October 10, 2000 

Adopted On: April 14, 2004 

HISTORY OF FLIGHT 

On October 10, 2000, at 1452 central daylight time,1

 a Canadair Challenger CL-600-2B16 

(CL-604) (Canadian registration C-FTBZ and operated by Bombardier Incorporated) was 

destroyed on impact with terrain and postimpact fire during initial climb from runway 19R at 

Wichita Mid-Continent Airport (ICT), Wichita, Kansas. The flight was operating under the 

provisions of 14 Code of Federal Regulations (CFR) Part 91 as an experimental test flight.2

 The 

pilot and flight test engineer were killed. The copilot was seriously injured and died 36 days 

later.

3

A review of air traffic control (ATC) and cockpit voice recorder (CVR) transcripts from 

the accident flight indicated that the pilot in the left seat was performing the pilot-in-command 

(PIC) and pilot-flying (PF) duties and that the copilot was performing the radio communications 

and other related pilot-not-flying (PNF) duties.4 The flight test engineer was to perform test 

flight configuration and monitoring duties at his workstation in the cabin. The flight crew was to 

initiate a standard takeoff and climb and conduct flight testing of modified pitch feel simulator 

 1

 Unless otherwise indicated, all times are central daylight time based on a 24-hour clock. The actual time of 

accident is approximate, based on flight data recorder (FDR) and air traffic control (ATC) information. 2

 Experimental and engineering test flights are flown to determine whether newly designed and experimental 

aircraft operate according to design standards. Based on these flights, test pilots make suggestions for 

improvements. Production test pilots test new airplanes for airworthiness after the airplanes come off the assembly

line and before they are delivered to customers. 3

 According to 49 CFR Section 830.2, for classification purposes, a fatal injury is one in which death results 

within 30 days of the accident. 4

 The accident flight was also a training and orientation flight for the copilot. 

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2

(PFS) units5 above 8,000 feet above ground level (agl).6 The test required that the airplane be

configured with an aft center of gravity (c.g.).7

The accident flight was the second flight to collect data to obtain certification by the 

United Kingdom’s Civil Aviation Authority (CAA) for two customer airplanes in the United 

Kingdom. Following the first flight in 1999, the CAA provided a list of unacceptable items that 

Bombardier needed to correct before the Challenger 604 could obtain CAA certification, 

including modification of the PFS units.8

 

On September 29, 2000, about 1806, the airplane returned to Wichita from other flight 

test operations in Fairbanks, Alaska, and was not flown for about 1 week in preparation for the 

flight testing of the modified PFS units. On October 6, 2000, the production PFS units were 

removed and the modified PFS units were installed. The airplane was loaded with 1,100 pounds 

of water ballast and 734 pounds of tail ballast for an aft c.g. test configuration. 

A ground test with the modified PFS units was performed to determine the control 

column travel needed for full elevator travel in both directions. The test also repeated the 

baseline tests that were previously conducted with the production PFS units. The ground tests

were designed to measure and record force at the control column in pitch at different column

positions and at different stabilizer positions. Two systems engineers from company headquarters

in Montreal (who also attended the preflight briefing for the accident flight) were present during

the static ground tests. Documentation indicated that no anomalies were noted with the PFS 

installations.

About 1330 on October 10, 2000, a preflight briefing was held at the Bombardier Flight 

Test Center (BFTC) for the first flight with a modified PFS aboard the airplane. The preflight 

briefing was attended by the three flight crewmembers, a BFTC aircraft controller, a systems 

engineer, an avionics engineer, the project engineer, and the two systems engineers from 

 5 PFS units replicate aspects of the aerodynamic loads (absent in hydraulically driven control systems) through 

artificial feel and centering units, allowing the pilots to feel control input resistance. The units increase control column, 

control wheel, and rudder pedal resistance as the flight control surfaces are moved from their neutral positions. 6

 The maneuver to be flown for the flight test is known as a wind-up turn. During this maneuver, the airplane is 

put into a bank and the control column is continually pulled back to maintain the indicated airspeed. Control column

forces are evaluated throughout the maneuver. A Federal Aviation Administration (FAA) test pilot described the 

wind-up turn as “one of the hardest maneuvers to do in flight test.” 7 The airplane was equipped with a combination of fixed weights and interconnected forward and aft ballast tanks. 

A water/glycol mixture could be moved forward or aft between the tanks, to change the c.g. for flight test purposes. The 

movement of the water/glycol mixture is controlled by an electric pump operated by the flight test engineer, or through

gravity transfer (at an appropriate flight attitude). In addition, a lead ballast was located in the rear of the airplane. 8

 To comply with the PFS unit control force item listed by the CAA, Bombardier had the vendor (Lucas 

Aerospace Division of TRW Aeronautical Systems) modify the elevator control system’s PFS units to increase the

second break out force. The first breakout force is the force necessary to move the control column, rudder, or other

flight controls from the neutral position. The production PFS units provided initial movement of the control column

from zero after the first breakout force was exceeded. The column force then increases linearly with column position 

until a second breakout force is reached, after which the column force continues to increase with column position at

a reduced rate (to prevent excessive column movement). The modification on the accident airplane added shims at

the end of an internal spring to increase preload for the second breakout. The change increased the second breakout

point from the original 40 pounds to 50 pounds of force. According to Bombardier, the test flight was intended to

demonstrate that the modified PFS units were sufficient to meet the CAA requirements in the heavy weight/aft c.g. 

configuration. 

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Montreal. The BFTC aircraft controller stated that the briefing had been postponed several times

because the airplane was not ready. However, he added that there was no rush to fly that day and

that the airplane had no outstanding maintenance items when it was released about 1330. 

Statements from briefing participants indicated that several minutes before the briefing, 

the accident pilot asked the accident flight test engineer to obtain a risk analysis from BFTC’s

manager of flight test operations and safety. The manager of flight test operations and safety 

stated that he first learned about the test flight at this time. He stated that he assessed the flight’s

risk level as low because the airplane was operating within its c.g. range and because “the

modification was stabilizing.” 

The briefing began with a description of the airplane’s configuration and the presentation 

of load sheet information. The accident copilot reportedly asked, “why are we so far aft?”. The

flight test engineer responded that this configuration (with the production PFS units) was 

previously flown on airplane number 5991 (the accident airplane) with the CAA test pilot during 

the 1999 flight test. The flight crew reportedly responded, “okay.” The briefing continued with a 

presentation comparing the characteristics of the production PFS and modified PFS units. The 

pilot reportedly stated that the airplane was going to “handle like a pig.” According to briefing 

participants, flight test maneuvers and procedures to address potential anomalies in the modified 

units were not discussed. The briefing concluded about 1400 and flight crewmembers boarded 

the airplane about 1415. 

At 1420:33, the CVR recorded a sound similar to several warning systems being checked, 

followed by the “before engine start” checklist items and conversations about the airplane’s

systems. The right engine was started at 1432:07. The PIC performed two flight control sweeps 

at 1434:24. The first sweep included the aileron, rudder, and elevators. The second sweep was a 

slow control sweep of the elevators.9

At 1448:45, the tower issued a takeoff clearance and instructed the flight crew to fly a 

heading of 230°.

10 At 1449:21, the pilot stated, “okay, here we go,” and a sound similar to an 

increase in engine RPM was recorded 2 seconds later. At 1449:29, the pilot stated, “set thrust,” 

and the copilot responded, “thrust set” 6 seconds later. At 1449:37, the copilot called out 

“airspeed’s alive eighty knots.” At 1449:48 the copilot called out “V one” (takeoff decision 

speed) and “rotate”. The pilot responded, “okay, we’re flying,” followed by the copilot calling

out “V two” (takeoff safety speed). 

At 1449:51, the CVR recorded a sound similar to stick shaker11 for 2.2 seconds, during 

which time the pilot stated “whew,” and the flight test engineer stated “what are you doing?”. 

The CVR then recorded the mechanical voice warning “bank angle”12 and a sound similar to stall 

aural warning for 1.1 seconds at 1449:53.. “Bank angle” was recorded at 1449:54 and again at 

 9

 The flight control sweeps were flight test checklist items to collect data. 10 The pilot and copilot display control panels retained a selected heading of 230o in nonvolatile memory. 11 The stick shaker, or control column shaker, is designed to warn pilots of an impending aerodynamic stall, and

is accompanied by audible alerts and lights. For more information about the airplane’s stall warning system, see

section 1.8. 12 The CL-604 is equipped with an aural bank angle warning system. For more information about the airplanes

aural warning systems, see section 1.8. 

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1449:55. A sound similar to stick shaker was recorded for 0.15 seconds beginning at 1449:57, 

followed by “bank angle” again at 1449:57.36. 

At 1449:58, and for the next 2 seconds, a sound similar to stick shaker was recorded for

0.22 second, and the pilot stated, “hang on.” A sound similar to stick shaker” was recorded again 

for 0.3 seconds, the flight test engineer repeated “what are you doing?,” followed by a sound 

similar to stall aural warning for 0.82 seconds, and “bank angle” again. At 1449:59.59, the pilot 

stated, “hang on.” The recording ended at 1450:00. 

Witnesses reported seeing the airplane bank to the right after takeoff. They stated that the 

airplane’s right wing rolled and impacted the ground first and that the airplane exploded on 

impact. The airplane crashed through an airport perimeter fence and came to rest adjacent to a 

two-lane, north-south road. 

PILOT INFORMATION 

The pilots were certificated under Federal Aviation Administration (FAA) certification

requirements and held Transport Canada exemptions from holding Canadian pilot certificates. 

The Pilot Flying 

The PF, age 33, was hired by Bombardier Aviation Services in Tucson, Arizona, in July 24, 

1995, as a flight test pilot, where he performed airplane modification and supplemental type 

certificate (STC)13 test flights on Learjet 31A, Learjet 60, and Challenger 604 aircraft. He also

performed aerodynamic stall testing and system evaluation flights on Learjet customer service 

aircraft. He was hired at BFTC as an experimental test pilot on May 5, 1999. 

From August 1989 to October 1990, he performed avionics certification testing as a flight 

test engineer for an avionics manufacturer. He was employed as a captain on an Aero 

Commander 500 for 14 CFR Part 135 cargo operations from October 1990 to September 1993. 

From October 1993 to September 1995, he was employed as a captain on a Beechcraft Baron and 

Piper Chieftain and as a first officer on a North American Saberliner for an unscheduled Part 135 

cargo and passenger operator. 

He held an airline transport pilot (ATP) certificate issued on August 25, 1991, with type 

ratings in the CL-65 (Canadair Regional Jet), CL-604, Learjet-60, and Bombardier BD-700 

(Global Express). In addition, he was a certified flight and ground instructor. His first-class 

medical certificate was issued on May 16, 2000, with the limitation “holder shall wear corrective 

lenses.” 

According to FAA documents, the pilot received an order of suspension of his ATP

certificate on July 19, 1996, for failure, as PIC, to ensure that cargo aboard a Part 135 cargo flight 

was secured to prevent shifting under anticipated flight and ground conditions. The suspension was

later withdrawn and replaced with an order of assessment on September 27, 1996, fining the pilot

$750. 

 13 An STC authorizes alteration of an aircraft engine or other component that is operated under an approved 

type certificate. 

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According to company records, he had logged 6,159.3 hours flying time, including 

1,187 hours at Tucson Production Flight Test; 359.3 hours engineering flight test flying time at 

BFTC; 557.2 hours of production flight test PIC time at Tucson; and 126.4 hours of engineering 

flight test as PIC at BFTC. He had logged 189 flying hours in the Challenger 604, of which 94.6

hours were as PIC. He received his initial type rating in the Challenger 604 on October 15, 1998. 

His last proficiency check was accomplished on March 24, 2000.14 According to BFTC’s manager 

of flight test operations and safety, there was no record that the pilot flying had received formal test

pilot training. Bombardier’s vice president of flight tests stated that the PF was assigned to entrylevel flying assignments as an experimental test pilot and flights typical of normal flight operations. 

The PF had a bachelor of science degree in aviation technology.

The PF had flown a total of 95.7 hours, 55.2 hours, 4.6 hours and 1.9 hours in the last

90 days, 30 days, 7 days and 24 hours, respectively. The pilot was off duty on October 8, 2000. He

worked from 0800 to 1800 on October 9 and returned to work on the day of the accident at 0800.

The Copilot 

The copilot, age 43, was hired by Bombardier on February 1, 1999. He was a former U.S.

Air Force F-15 fighter pilot and instructor pilot. He was employed as a test pilot by Swearingen

Aircraft Company, where he performed development and certification test flights on Metroliner

airplane systems from August 1991 to January 1994. In addition, he was employed as an

engineering test pilot on high-performance jet prototypes at Cessna Aircraft Company. He 

performed developmental and certification test flights involving performance and handling qualities,

stalls, and envelope expansion on Cessna Citation and Excel airplanes in Wichita from January 12, 

1994, to January 29, 1999. He was also an FAA-designated engineering representative. 

He held an ATP certificate issued on June 10, 1990, with type ratings in the Cessna CE500, CE-525S, CE-560XL, CE-650, CE-750, Bombardier CL-65 (Regional Jet), CL-604, and SA227 Metro III. He was a certified flight instructor and held an airframe and powerplant certificate

issued on January 4, 1979. His first class medical certificate was issued on September 27, 2000,

with no limitations. 

According to company records, he had logged 6,540.7 hours of flying time,

15 including 

463.7 hours at BFTC; of which 254.4 hours were as PIC at BFTC. He had logged 6,076 flying 

hours when he was hired by Bombardier, of which 2,123 hours were flight test. He had attended a 2-

week test pilot short course, according to company records. He had 1.2 hours flying time in the

Challenger 604, of which 0.4 hours were as second in command. He received his type rating in the

CL-604 on June 23, 2000. This was also his last proficiency check. He had flown a total of 88.1 

hours and 17.1 hours in the last 90 and 30 days, respectively. He had logged no flying hours in the

last 7 days or 24 hours. 

 14 Recurrent simulator training was the only formal proficiency check performed by Bombardier at the

company’s commercial training facility in Montreal. 15 Pilot logbook information indicates a total time of 6,585.5 hours. 

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The copilot had returned from Amsterdam, Holland, on October 8, 2000, about 2230. On 

October 9, 2000, he worked from 0715 to 1630 and returned to work on the day of the accident 

at 0730. 

AIRPLANE INFORMATION 

The accident airplane, serial number 5991, was registered and owned by Bombardier Inc., 

Canadair, and was equipped with two General Electric CF34 turbofan engines. Manufactured in 

1994, the airplane was used exclusively as an engineering development and sustaining program test 

airplane. The airplane was operated on a Canadian flight permit (experimental type certificate) and 

was not issued an airworthiness certificate. A special flight authorization (SFA)

16 was issued by the 

FAA’s Wichita Manufacturing Inspection District Office (MIDO) on September 5, 2000. The SFA

was issued to conduct flight test(s) required to obtain a U.S. type certificate. The SFA stipulated the 

operational conduct and limitations for the flight crew and airplane. 

The airplane fuel tank system comprised a left wing tank, right wing tank, auxiliary fuel

tank and tail fuel tank (see figure 1). The auxiliary fuel tank system beneath the center cabin had 

a forward, center, and aft tank that were interconnected by pipes and that were not isolated from 

each other by shutoff valves or check valves. The tail fuel tank system had two saddle tanks and 

a third tank at the rear of the tail cone. (see figure 1). 

Figure 1. Airplane Fuel System Diagram

The airplane was equipped with a ground proximity warning system, which provided voice 

message alerts. The “bank angle” voice message is based on the airplane’s roll attitude and radio 

 16 A special flight authorization permits a foreign-registered civil aircraft that does not have the equivalent of a 

U.S. standard airworthiness certificate to be operated within the United States. 

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altitude. The roll angle limit ranges linearly from 10° at 30 feet agl to 40° at 150 feet agl. It ranges

from 40° at 150 feet agl to 55o at 2,450 feet agl. When the airplane’s roll angle exceeds the alert 

threshold, the “bank angle, bank angle” aural alert activates. An additional “bank angle” alert is

generated if the roll angle increases by another 20 percent of the threshold. If the roll angle exceeds 

140 percent of the threshold, an aural alert is issued every 3 seconds. 

The airplane’s stall warning system provided aural, visual, and tactile warning of an 

approaching stall. As the airplane’s vane angle of attack (AOA)17 increases, tactile warning is 

provided by a stick shaker. A further increase in vane AOA activates a stick pusher. Visual stall

warnings are provided by flashing red “STALL” annunciators on the left and right glareshield and 

by a low-speed indicator on each of the primary flight displays. An aural warbler warning begins

when either stall channel signals the pusher to fire. Both channels are required to activate the pusher. 

In addition to the warnings, the autopilot disconnects and continuous ignition is activated. 

The stick pusher forces the control columns forward to lower the nose (AOA) and are 

designed to prevent an aerodynamic stall. The system’s dual (left and right) channel stall protection

computer (SPC) monitors the following inputs to calculate the AOA trip points: 

• AOA 

• Lateral acceleration 

• Flap position 

• Weight on wheels 

• Altitude 

• Weight on wheels fail 

In the event of an AOA rate increase greater than 1° per second, the SPC lowers the AOA 

trip points (phase advance) to prevent the airplane’s pitching momentum from carrying it 

through the stall warning/stick pusher sequence into the stall. An acceleration switch 

disconnects the stick pusher mechanism if less than 0.5 G is reached during the stick pusher 

activation. The stick pusher can also be de-activated by pressing and holding the autopilot/stick 

pusher disconnect switch located on the pilot’s and copilot’s control wheel. The stick pusher is 

capable of operating immediately once the autopilot/stick pusher switch is released. In case of 

malfunction, the stick pusher can be disabled by selecting the “PUSHER” switch to “OFF” on 

the pilot’s or copilot’s stall protection panel. Both the pilot’s and copilot’s switches must be in 

the “ON” position for stick pusher activation. 

The accident airplane’s SPC actuation could be modified for flight test purposes. After 

takeoff, and the removal of weight from the landing gear, the nominal design provides for a 2-

second interruption (time out) of the phase advance for shaker and pusher activation. During this 

time, the SPC activation angles for the shaker and pusher are not phase advanced, and will 

activate only if the AOA threshold is exceeded. The accident airplane’s SPC could be adjusted to 

interrupt the phase advance to the AOA threshold. Examination of flight test data indicated that 

of the two SPC channels, the left timed out at 5.5 seconds on the airplane’s three previous flights 

 17 Stall protection vanes are located on the left and right side of the fuselage. They measure the local airflow on 

the forward fuselage. The stall vane measured angles are used to derive the airflow over the airplane’s wings and 

provide stall warning and stall prevention. All AOA values in this report are vane AOA. 

 NTSB/AAB-04/01 
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and the right channel timed out at 2.0 seconds, which is the production standard.18 According to 

Bombardier documents included in a November 5, 2001, letter to the National Transportation 

Safety Board, there was insufficient data to determine the timeouts for the accident flight. The

letter stated that although the left shaker activation may have been delayed, the increased timeout 

would not have affected stick pusher activation. 

The following are normal production shaker and pusher activation vane angles:19

Shaker 19.2o with a tolerance of +/- 0.35o 

Pusher 23.1o with a tolerance of +/- 0.35o 

Recorded test flight data indicated that the activation vane angles for the accident airplane 

were set at the following values: 

Shaker Left Channel 19.7o 

Shaker Right Channel 19.3o 

Pusher Left Channel 23.6o 

Pusher Right Channel 23.2o20

No mechanical flight control system discrepancies were reported during the 30-day period 

before the accident. 

Airplane Limitations 

 

The Challenger 604 Operating Manual contains weight and balance information for a

normal category, certificated CL-604. According to a restriction and/or special instruction, the 

accident airplane had an expanded weight and balance envelope for takeoff and landing. The c.g. 

range changes based on airplane configuration. According to the CL-604’s type certificate data 

sheet (No. A21EA), the airplane’s aft c.g. limit was 38 percent mean aerodynamic chord (MAC) 

between airplane weights of 43,000 and 47,700 pounds. The accident airplane’s weight at takeoff 

was 44,849 pounds. 

Weight and Balance and Performance Calculations 

The preflight weight and balance data for the accident flight were as follows:

 

Zero Fuel Weight 29,254 lbs.

Left Wing Fuel 4,850 lbs. 

Right Wing Fuel 4,850 lbs. 

Center Fuel 3,800 lbs. 

Aft Fuel 2,500 lbs. 

18 No SPC maintenance was recorded during the period that included the airplane’s final five flights. 19 The non-phase advanced shaker and pusher angles are based on a flap setting of 20o and a pressure altitude of

less than 2,000 feet. 20 The stick pusher activates when each vane angle (on the left side and right side of the airplane’s nose) reaches 

the preset activation angle.

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Ramp Weight 45,254 lbs.

c.g. 37.4 percent MAC 

Flight test tolerances for the accident flight were as follows: 

• Stick Shaker/pusher set to nominal

• Test weight tolerance: +5 percent to –1 percent

• c.g. position tolerance: 7 percent of total travel 

• Airspeed tolerances are 3 knots 

• Non-turbulent conditions

Postaccident Fuel Weight Calculations and Weight and Balance 

The CL-604 fuel computer uses a fixed constant fuel weight (density)21 of 6.75 pounds 

per U.S. gallon (variability of density due to nonstandard temperature was not considered in the

equation).22 After the accident, Bombardier recalculated the airplane’s weight and balance based

on a takeoff weight of 44,849 pounds and a fuel weight value of 6.75 pounds per gallon.23 In a

December 13, 2000, memorandum to the Safety Board, Bombardier’s calculations indicated that 

the airplane’s c.g. was 37.9 percent MAC at the start of the takeoff roll. 

In addition, Bombardier recalculated the airplane’s c.g. estimating both the shift within 

the tanks and the amount of fuel transfer between fuel tanks during the takeoff roll and initial 

rotation. The transfer rates calculated between fuel tanks were as follows: 

Forward auxiliary tank to center auxiliary tank 0.735 gallons per second 

Center auxiliary tank to aft auxiliary tank 0.875 gallons per second 

Saddle tanks to tail cone tank 0.484 gallons per second 

The following table compares fuel tank quantity and transfer changes between the start of 

the airplane’s takeoff roll (zero pitch angle as the airplane accelerated down the runway before

rotation) and 20 seconds later with an airplane pitch angle of 13.8°at rotation:24

Table 2. Comparison of Fuel Tank Quantity and Transfer Changes 

Tank Before Acceleration, at Zero Pitch Angle 13.8° Pitch Angle, at Rotation 

Forward Auxiliary 41.5 gallons 26.8 gallons 

Center 491 gallons 488.2 gallons

Aft Auxiliary 26 gallons 43.5 gallons 

Saddle Tanks 212.5 gallons 202.8 gallons

Tail Cone 165 gallons 174.7 gallons

 21 FAA publication FAA-H-8083-1, Aircraft Weight and Balance Handbook, states that fuel weight is 

determined by its specific gravity and temperature. 22 The standard day, sea level density for Jet A fuel is about 6.789 pounds per U.S. gallon. 23 Fuel samples taken at the Bombardier facility on November 16, 2000, nearly matched the typical fuel density

of 6.75 pounds per gallon. 24 The 13.8° value was chosen as a minimum flow, or best-case scenario assuming fuel shifts near rotation.

 NTSB/AAB-04/01 
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In addition, Bombardier stated that fuel could also shift between rib bays in the airplane’s

wing fuel tanks. Based on Bombardier fuel shift calculations evaluated by the Safety Board staff, 

the airplane’s c.g. increased to 40.5 percent MAC by the time it reached a 13.8° pitch angle 

20 seconds later.

25 

Postaccident Center-of-Gravity Related Airworthiness Directives 

The fuel shift/c.g. issue was addressed by Bombardier, Transport Canada and the FAA

following the accident. On February 1, 2001, Bombardier issued a temporary revision to the 

Challenger flight manual changing the airplane’s aft c.g. limit from 38 percent MAC to 34.5 or 

35.0 percent, depending on airplane weight. The same day, Transport Canada issued 

Airworthiness Directive (AD) CF-2001-07 to make the revision permanent. The FAA issued 

emergency AD 2001-03-52 on February 2. The FAA’s AD stated that the Challenger’s “fuel tanks 

are not baffled, which allows fuel to migrate when the airplane pitches up.” The AD added that 

“fuel migration under conditions of acceleration and/or climb, if not corrected, could result in the 

airplane exceeding the aft center of gravity limit, and consequent loss of control of the airplane.” 

The AD stated that the revision was intended to “prevent fuel migration from resulting in a 

rearward shift of the c.g. to the degree that will result in controllability problems.” 

METEOROLOGICAL INFORMATION 

The ICT automated surface observing system (located 4,500 feet from the approach end of

runway 19R) recorded the following information at 1450: 

Wind 190° at 20 knots gusting to 26 knots; 10 statute mile visibility; few clouds at 

12,000 feet agl; scattered clouds at 20,000 feet agl; temperature 17° Celsius (C); 

dew point of –11° C; altimeter 30.21 inches of mercury. Peak wind of 29 knots 

from 170°occurred at 1400. 

No microburst or gust front activity was recorded between 1250 and 1450. According to the

low-level wind shear alert system, centerfield winds were generally from the south/southwest with

speeds from 15 to 22 knots. 

AIRPORT INFORMATION 

ICT is located about 5 miles southwest of Wichita. The airport has three concrete runways:

01L/19R (10,300 feet by 150 feet, grooved concrete), runway 01R/19L (7,302 feet by 150 feet) and 

runway 14/32 (6,301 feet by 150 feet). The airport is equipped with aircraft rescue and firefighting 

(ARFF) units under provisions of 14 CFR Section 139.317 Index C.26

 25 The value of 40.5 percent MAC does not include tolerances for c.g. position or for changes in fuel density

that could change this MAC value by more than 1 percent in either direction. 26 Index C includes air carrier aircraft of at least 126 feet in length but less than 159 feet in length. According to 

14 CFR 139, a minimum of two or three ARFF vehicles must carry a total quantity of 3,000 gallons of water for 

foam production. 

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Twelve air carriers and three fixed base operators serve the airport. In addition to 

Bombardier, two other airplane manufacturers use the airport for flight test operations. The air

traffic count from September 1999 to September 2000 was 180,878 flights.

FLIGHT RECORDERS 

The airplane was equipped with an airborne data acquisition system (ADAS) capable of 

recording 1,780 flight test data parameters. The magnetic flight test data tape and the digital flight 

data recorder (FDR) tape, which recorded additional parameters, were recovered from the

wreckage. Thermal damage destroyed ADAS flight test data recorded after takeoff rotation. Safety 

Board staff synchronized the instrumented data with the recovered FDR data.

27

The airplane was equipped with a Fairchild model A-100A CVR. The CVR exterior 

received some structural and fire damage. The interior and the tape were not damaged. The 

recording comprised four channels of good quality audio information.28 A transcript was 

prepared from the entire 31-minute recording. 

WRECKAGE AND IMPACT INFORMATION 

The airplane first impacted the ground 437 feet from the intersection of runway 19R’s 

centerline and the extended centerline of taxiway B. The airplane came to rest upright about 

1,174 feet from the initial ground impact scars and 850 feet to the right of the runway centerline. 

Wreckage was found along the entire path. Parts of the right wing, radome, and nose structure 

were found within the first 300 feet of the wreckage path. A large concentration of right engine 

structure was found just past the wreckage path’s midway point. The left wing was found largely 

intact and attached to the fuselage. The right wing was consumed by fire. The empennage 

separated from the fuselage and was heavily damaged by fire. It came to rest in a drainage ditch 

near the fuselage. Flight control cables were found in their approximate correct locations 

throughout the wreckage, but complete cable continuity could not be determined because of

extensive right wing and empennage damage. Fuel system components in the fuselage and right 

wing were consumed by fire. 

Wreckage of both engines was recovered in the debris field. The left engine was found 

attached to the fuselage. The right engine was located on the road, about 30 feet behind the 

fuselage. An external examination did not reveal evidence of pre-impact anomalies. 

 27 For more information on the synchronization of flight test and FDR data, see the Flight Data Correlation Study in

the Safety Board’s docket for this accident. 28 The Safety Board uses the following categories to classify the levels of CVR recording quality: excellent, 

good, fair, poor, and unusable. An excellent recording is one that is very clear and easily transcribed. A good

recording is one in which most of the crew conversations can be accurately and easily understood. The transcript

that is developed may indicate unintelligible words or phrases. Any loss in the transcript can be attributed to minor

technical deficiencies or momentary dropouts in the recording system or to a large number of simultaneous 

cockpit/radio transmissions that obscure each other. A poor recording is one in which a transcription is nearly

impossible because a large portion of the recording is unintelligible. 

 NTSB/AAB-04/01 
12

The flight spoiler power control units were found in the stowed position. The extensions

of the flap actuator jackscrews were replicated on a similar airplane in the Challenger Service

Center, and the flap setting was calculated to be about 20o. 

The cockpit’s left side was heavily sooted close to the floor and the multifunction

displays (MFD) in the instrument panel were damaged by heat. The instrument panel was 

displaced aft and downward. The outboard edge of the instrument panel was separated from its

structure and displaced aft, inboard, and downward. The control yoke was turned to the right.

Both rudder pedals were jammed against the forward bulkhead. The windshield was crazed and 

sooted. 

The cockpit’s right side was crushed into the copilot’s seat. The outboard corner of the 

instrument panel was separated from the structure and displaced inboard about 3 inches. The 

floor beneath the copilot’s station was displaced upward about 6 inches and rearward about

14 inches. The copilot’s MFDs were heat damaged. The floor forward of the seat was destroyed 

and displaced rearward with the rudder pedals visible from outside the airplane. The outboard 

lower side panel was displaced inboard and separated from the structure. The upper panel was 

displaced rearward. The circuit breaker panel bulkhead was displaced downward about 9 inches 

at its forward side and was free of its upper attachments. 

The right side wall and outer cabin floor structure in the forward-to-mid cabin, forward of 

the flight test engineer’s station, were destroyed by fire.29 

MEDICAL AND PATHOLOGICAL INFORMATION 

Autopsies of the PF and flight test engineer were conducted by the Sedgwick County 

Regional Forensic Science Center in Wichita, Kansas. According to the autopsy report, the pilot 

died at the scene of the accident after suffering blunt force trauma, smoke inhalation and burns.

The cause of death was listed as “carbon monoxide toxicity and smoke inhalation.” The flight 

test engineer died at the scene of “blunt force trauma of head and neck.” The report added that he 

also suffered “postmortem thermal burns,” fractured vertebrae and cervical spinal cord

lacerations. There was no evidence of carbon monoxide or soot in his airways or lungs, 

according to the autopsy report. The copilot, who sustained blunt force trauma and burns, was 

removed from the cockpit by rescuers and transported by ambulance to a local hospital, where he 

arrived about 1548 hours. He died on November 15, 2000, of “complications from thermal 

burns.” 

The Regional Forensic Science Center and the FAA’s Civil Aerospace Medical Institute 

performed toxicological testing of the pilot and flight test engineer. The tissue and blood 

specimens tested negative for a wide range of drugs, including major drugs of abuse.30 

 29 For information about the cabin passenger door, emergency exit and the flight test engineer’s seat see the 

section titled, “Survival Aspects.” 30 The five drugs of abuse tested in the postaccident analysis are marijuana, cocaine, opiates, phencyclidine, and 

amphetamines. 

 NTSB/AAB-04/01 
13

EMERGENCY RESPONSE 

Two ARFF vehicles arrived at the accident site within 90 seconds, according to ARFF 

dispatch logs and personnel statements.31 Wichita Fire Department (WFD) was notified about 

1452 and the first unit arrived about 1458, according to WFD dispatch logs. WFD responded 

with 48 personnel and 23 vehicles. Both pilots were reported to be conscious when the initial

ARFF units arrived at the accident site. 

Access to the crash site from the airport was hampered by the damaged fence and by a

ditch along the road. ARFF vehicles Safety 1 (S-1) and Safety 3 (S-3)32 responded first with 

three firefighters, all of who were wearing protective gear. S-3, manned by one driver, was first 

to arrive. ARFF vehicle S-1 arrived with a driver and the airport police captain. The ARFF 

training captain and the ARFF deputy chief followed in an airport pickup truck, along with ARFF 

vehicle S-2, which was manned by one driver. The ARFF chief arrived in his car. 

The drivers of vehicles S-1 and S-3 initially remained in their trucks and used foam to 

extinguish the fuselage fire and burning fuel under the airplane. The S-3 driver stated that, when 

he arrived, the fuselage was “engulfed in flames, even the roof.” He stated that he first used his 

roof turret to extinguish fires on the left wing and the airplane’s left side and top before moving 

into position to put out fires on the right wing and fuselage. 

After the S-2 vehicle arrived, the driver of S-3 exited his vehicle and assisted the training 

captain, who was attempting to break holes in the cockpit side windows to direct water from 

hand-held hoses into the cockpit and onto the pilots.33 ARFF personnel used fire axes, 

sledgehammers, and crowbars to break holes in the left and right side cockpit windows. A hole 

was first made in the cockpit’s left side window, and water was directed into the cockpit to 

suppress the fires and protect the flight crew. A second hole was also punched through the 

copilot’s window.

34 

Upon their arrival, firefighters observed an impact-related hole on the top of the 

fuselage’s left side (located aft of the main passenger door and forward of the left wing) and 

directed fire extinguishing agent through the hole. After WFD personnel arrived, forced entry 

tools (hydraulic cutters and spreaders) were used in an unsuccessful attempt to force the 

 31 ARFF officers and firefighters reported that they first heard a loud noise and saw black smoke at the west side 

of the airport. The crash alarm activated as personnel were running to their vehicles. The ARFF chief stated that,

before he responded to the scene, he confirmed that the ARFF dispatcher had contacted 911 and had requested

mutual assistance from Sedgwick County and the Wichita Fire Department (WFD). 32 In addition to two police cars, the airport had four ARFF vehicles: S-1 was a 1997 quick response vehicle 

equipped with 300 gallons of water, 40 gallons of 3 percent aqueous film forming foam (AFFF) and 450 pounds of

dry chemical agent. Safety 2 and 3 were Oshkosh T-1500 vehicles equipped with 1,585 gallons of water, 205 gallons

of 3 percent AFFF and 700 pounds of dry chemical agent. S-4 was an Oshkosh M-1500 equipped with 1,500 gallons 

of water and 180 gallons of 3 percent AFFF; S-4 was undergoing maintenance and did not respond to the accident. 33 According to the Federal Aviation Regulations (FAR), cockpit front and side windshield panes and the 

supporting structure for these panes must withstand, without penetration, the impact of a 4-pound bird when the

velocity of the airplane (relative to the bird along the airplane’s flightpath) is equal to the value of Vc (design cruise 

speed) at sea level, described in 14 CFR 25.335(a). Vc for the accident airplane is 300 knots indicated airspeed

below 8,000 feet. 34 Several smaller holes were punched through the left and right front windows. 

 NTSB/AAB-04/01 
14

passenger door open. According to ARFF personnel statements, no attempts were made to open 

the emergency hatch over the right wing. ARFF personnel stated that they were aware of the 

hatch’s location and operation. ARFF personnel reported that the hole on the left side of the 

airplane provided sufficient access to the cabin and that entry through the hatch was not 

necessary. 

WFD assisted with additional forced entry tools to enlarge the holes in the side cockpit 

windows, and to enlarge another hole located on the left side of the fuselage and forward of the 

wing. Additional water spray was used to protect the WFD firefighters who entered this hole to

rescue the flight crew. The copilot was extricated from the cockpit about 20 minutes after ARFF 

units arrived and was transported to a hospital about 1541. The PF died before he could be 

extricated. The flight test engineer was found dead in the cabin near the cockpit bulkhead. 

The ARFF S-2 truck was equipped with a penetrator nozzle, which can be used to pierce

an airplane’s fuselage to deliver water or foam inside the airplane. ARFF personnel stated that 

two firefighters were needed to prepare and operate the nozzle and hose. The ARFF chief stated

that “only three ARFF personnel [were] on scene in first arrivals and they concentrated on 

knocking down the fire that was on both sides of the airplane.” The chief stated that additional 

firefighters would have aided rescue efforts. 

An ARFF captain/supervisor stated that the “tower provided us with no information...in 

the first three, four, five minutes at the scene. We knew nothing that was on there. We didn’t even 

know if this was a commercial airplane, test airplane or whatever.” 

A fuel-fed vegetation fire was also extinguished. One ARFF officer was treated for smoke

inhalation. 

Emergency Response Training 

At the time of the accident, multiagency drills at ICT were held quarterly and involved 

ARFF and law enforcement personnel, the Sedgwick County Fire and Sheriff’s departments, and 

the Wichita fire and police departments. 

ARFF personnel had received familiarization training on air carrier and military airplanes 

that use the airport. No similar training was provided for flight test airplanes based at the airport, 

which are frequently equipped with special features including ballistic-initiated spin recovery

parachutes, forced entry locations, and pyrotechnic-operated emergency hatches. 

At the time of the accident the Airport Authority’s Airport Safety Division employed 24 

people, who received law enforcement and ARFF initial and yearly recurrent training. Four

people were assigned to ARFF duties and two were assigned to airport law enforcement duties 

for each 8-hour shift. 

The Safety Board addressed ARFF staffing concerns when it issued Safety 

Recommendation A-01-65 to the FAA. Safety Recommendation A-01-65, issued on October 23, 

2001, asked the FAA to “amend 14 Code of Federal Regulations 139.319 (j) to require a 

minimum Aircraft Rescue and Fire Fighting staffing level that would allow exterior firefighting 

and rapid entry into an airplane to perform interior firefighting and rescue of passengers and 

 NTSB/AAB-04/01 
15

crewmembers.” In a February 19, 2002, letter to the Safety Board, the FAA stated that it had 

asked the Aviation Rulemaking Advisory Committee (ARAC) Airports Issue Group to create an

ARFF Requirements Working Group to examine ARFF staffing levels as part of an overall 

ARAC review of 14 CFR Part 139. On October 17, 2002, Safety Recommendation A-01-65 was 

classified “Open—Acceptable Response,” pending results of the ARAC working group and 

implementation of the recommendation. 

SURVIVAL ASPECTS

The airplane’s configuration comprised pilot and copilot seats, a cockpit jump seat, and a 

flight test engineer station in the airplane cabin. The flight test engineer’s station was located on 

the right side of the cabin. The seat was located adjacent to the emergency exit over the right 

wing. All crew seats were equipped with 5-point adjustable restraints. The pilots survived the 

impact sequence, but injuries and damage to the forward fuselage and cockpit prevented them 

from escaping unaided. 

A manually operated, downward-opening main passenger door (with integral stairs) was 

located on the left side of the fuselage, aft of the cockpit. The main passenger door was found 

fully closed and latched. Safety Board staff examination revealed that the fuselage had buckled 

into the door, with evidence of shear and/or compression overload (skin wrinkles) on the forward 

fuselage and cabin door. Attempts by Safety Board investigators to open the door manually 

(with the inside and outside releases) were unsuccessful. The exterior handle was found out of 

its stowed position in a horizontal position; the handle could be moved 1.5 inches

counterclockwise from the horizontal. Further investigation revealed that the mechanical 

fasteners that attach the aft center latch cam to the torque tube were sheared. The door’s interior

and latching mechanism exhibited evidence of a compressive overload to the door’s lower 

tension rod and buckling damage to the door intercostals. An internal inspection of the door 

structure revealed damage to the forward part of the door stairs. 

The airplane was equipped with an inward-opening, plug-type emergency exit hatch over 

the right wing. The exit can be opened from either inside or outside the airplane. The hatch was 

found in the closed and secured position. Postaccident examination determined that the exit was 

operational from the outside and inside. 

The cockpit was not equipped with egress hatches. The airplane’s windows were an 

integral part of the airframe structure and could not be opened. Pilot and passenger egress was 

through the forward passenger door or through the over wing hatch. 

The flight engineer’s station was located in the middle of the cabin near the right overwing emergency hatch. Firefighters found the flight test engineer’s seat in the forward cabin near

the flight test engineer’s body. The seat swivel adjustment was found locked in the forward 

facing position. The seat was separated by impact forces from its floor mounts and seatback 

vertical supports. The seat mounts were found attached to the floor seat track. No floor damage

was found at the flight test engineer’s station. There was no evidence of fire damage or sooting 

on the floor mounts. The restraint system was found attached to the seat by the tie down strap on 

the forward frame of the seat pan. The five point restraint system end fittings were found latched

inside the release buckle. The left and right seat belts and shoulder harness straps were burned 

 NTSB/AAB-04/01 
16

through. The seat was designed to withstand the following loads: 9 G forward, 4 G lateral, 4.65 

G up and 8.1 G down. 

TESTS AND OTHER RESEARCH 

Airplane Performance 

Safety Board staff conducted an airplane performance study as part of the accident 

investigation (see figure 2). According to FDR, CVR and flight test data, the nose gear strut was

extended (before elevator input) as weight diminished on the nose gear about 0.5 second before 

rotation. Main gear liftoff occurred about 1449:50, as the airspeed reached 143 knots. FDRderived data indicated that the PF used about 10° of nose-up elevator to initiate rotation, and 

main gear liftoff occurred about 1.2 seconds later, with a pitch angle of between 2.8° and 3.8°. 

The 10° nose-up elevator input was maintained for 0.8 second after liftoff until the pitch attitude

reached 12°, according to FDR data. Pitch attitude continued to increase over the next 1.4

seconds, peaking at 20°, while nose-up elevator input decreased from 9° to 1° nose up. 

According to the FDR, the vane AOA reached 23°about 3.4 seconds after start of rotation. 

According to Bombardier, the airplane enters the stall warning region after reaching an AOA of 

19°. 

FDR data indicated that the airplane began an uncommanded right roll just before

reaching peak pitch attitude. The CVR recorded the sound of the stick shaker at 1449:51, and the 

stick shaker sound continued for 2.2 seconds. During this time, a nose-down elevator input of 

about 14° was recorded, followed by a 5.5° nose-up elevator control input, consistent with pilot 

control inputs to correct the airplane’s pitch and roll oscillations. The pitch attitude decreased to

4.3° nose up and the bank angle increased to about 80° right-wing down. During the next

3 seconds, the airplane rolled left to about wings level as the pitch attitude increased to 18° nose 

up. The vane AOA on the second pitch up was 26.4°. The second pitch up oscillation was 

followed by a second pitch down to -2°, and a right-wing down roll to 61°. This pitch down was

followed immediately by a pitch up and roll back to wings level, reaching nearly level pitch 

attitude and 40° right-wing down at impact, according to FDR data. Peak nose-up elevator input 

at this time (1449:55) was about 16°. 

The CVR recorded the intermittent activation of stick shaker, aural stall, and bank angle

warnings beginning with the first pitch up to 20° until about 1 second before impact. After initial 

rotation, all elevator, rudder, and aileron inputs by the pilot were consistent with inputs to 

counter pitch and roll oscillations, according to FDR information. FDR data indicated a peak 

pitch rate of 8.4° per second. (The airplane’s ADAS, which recorded test flight data at a higher

sampling rate, indicated a pitch rate of 9.6° per second). 

According to FDR data and information derived from the Safety Board staff’s integration 

study of FDR data (flightpath integration), the airplane’s peak airspeed was 170 knots. The

flightpath integration indicated that the airplane’s peak altitude was about 70 feet. FDR information

indicated that the engines were operating at 90 percent fan speed until impact. 

 NTSB/AAB-04/01 
17

Figure 2. 

Review of the Pilot Flying’s Previous Takeoff Performance 

Safety Board staff reviewed flight data to determine the peak pitch (rotation) rates per

second during previous takeoffs performed by the PF. 

Data showed a 7.2°-per-second rotation rate on a Challenger test flight on August 16, 2000.

The airplane’s ramp weight was 41,511 pounds and the c.g. was 31.0 percent MAC. Data also 

showed a 6.5°-per-second rotation rate on takeoff on a Challenger ferry flight from Barrow, Alaska, 

to Fairbanks, Alaska, on September 14, 2000, and a 6.0o-per-second rotation rate on takeoff from 

Fairbanks to Wichita on September 29, 2000, about 2 weeks before the accident. For the Fairbanksto-Wichita flight, the airplane’s ramp weight was 47,204 pounds and the c.g. was 35.5 percent

MAC. The 35.5 percent MAC was the farthest aft c.g. that the PF had flown in the accident airplane, 

according to Bombardier flight test records. According to Bombardier flight test data, the stall

protection system did not activate on these flights. The data indicated that the maximum pull control

column force exerted by the PF during these operations was generally greater than 40 pounds. 

Bombardier stated that the stick force used by the accident pilot during the accident flight rotation 

 NTSB/AAB-04/01 
18

“was near and within the upper limit of the normal range of stick forces, based on results from other

pilots.” 

The accident pilot also flew the Global Express in the weeks before the accident. Flight 592,

a Global Express BD-700-1A10 flight on September 22, 2000, showed a 8.3o-per-second pitch rate. 

A week earlier, on September 15, flight 589 showed a 6.8° rotation rate. A 5.8°-per-second pitch rate

was recorded for flight 599, another Global Express, on October 4, 2000. The takeoff c.g. range for 

the Global Express was between 23 percent and 35 percent MAC.

Bombardier compiled additional takeoff data from 50 flights flown by other BFTC pilots, 

which included operational flights, certification test flights, and the accident flight (flight 535).

According to Bombardier, the maximum pull control column force during normal operations was 

less than 40 pounds. The parameters examined were maximum pitch rate at rotation versus Mach 

number and c.g., and maximum control column forces at rotation versus c.g. 

Bombardier computed maximum AOA (alpha) measured by the alpha stall vane during 

rotation as a function of Mach number. According to Bombardier, the maximum alpha stall vane

angles recorded during operational takeoffs were about 14°. The maximum alpha stall vane angle

values during abused certification takeoffs (that is, nonstandard takeoffs conducted for flight test

purposes) were between 14°and 19°. The maximum alpha stall vane angle values for the accident

pilot’s operational takeoffs were between 15° and 17.5°. The maximum alpha stall vane angle for 

the accident flight was 23°. This angle was 4° above the normal setting for stick shaker activation, 

according to Bombardier. 

In addition, Bombardier data indicated that the maximum pitch rates during operational

takeoffs were 3.4o to 6.1o per second. Maximum pitch rates during abused (or nonstandard)35

takeoffs during certification were between 3.5o and 7.0o per second. The maximum pitch rates for

certification performance takeoffs were between 4.8o and 7.5o per second. The maximum pitch rates

for operational takeoffs performed by the accident pilot were between 6.0o and 7.6o per second. As

noted previously, the maximum pitch rate for the accident flight recorded by the onboard ADAS 

was 9.6o per second, according to recorded data. 

Center of Gravity and Pitch Feel Sensitivity Studies 

The Safety Board staff conducted c.g. and PFS sensitivity studies in an engineering flight 

simulator at Bombardier Aerospace facilities in Montreal as part of the accident investigation. 

The first c.g. study was conducted without pilots and used elevator values derived from the

accident flight’s FDR. The study indicated that with a c.g. of 37.9 percent MAC (the start of the 

takeoff roll), the alpha vane AOA did not reach the stick pusher value (for activation). At 40.5 

percent MAC (the c.g. after rotation), the alpha vane AOA peaked about 5° beyond stick pusher 

value (see figure 3).36

 35 The takeoff demonstrations included early rotation (Vr minus 5 knots) with one engine inoperative; early

rotation (Vr minus 10 knots, with a rapid rotation (or over rotation of 2o pitch) with all engines operating; and

maximum pitch mistrim within the takeoff trim band with all engines operating. 36 Simulator fidelity diminishes after entry into the stall. 

 NTSB/AAB-04/01 
19

37 38 39 40 41 42 43 44 45 46 47 48 49

-5

0

5

10

15

20

25

30

35

Note: Dashed lines are 37.9% mac c.g.

 Solid lines are 40.5% mac c.g. 

c.g. = 40.5% mac

c.g. = 37.9% mac

Stick Pusher

Stick Shaker

Effect of 37.9% to 40.5% cg shift

Challenger 604

Simulation Data

Alpha v

ane q

Time (sec)

Figure 3. C.g. Sensitivity and Stick Shaker/Pusher Threshold Values 

In a second c.g. study, an FAA test pilot and a Transport Canada test pilot, who were rated 

in the CL-604, performed takeoffs in the Bombardier engineering flight simulator to determine

the effects of c.g. location on rotation rate (and the ability to capture the prescribed takeoff pitch 

attitude) and to examine whether there were perceptible differences between the handling

characteristics of the modified PFS and the production PFS installed on in-service CL-604

airplanes. The pilots performed takeoffs with c.g. locations ranging from 35.0 percent MAC to

42.0 percent MAC. The pilots reported that aft c.g. positions caused them to rotate at a 

somewhat higher rate. The pilots noted that these effects were more noticeable when they used

increased rotation rates (about 6° instead of the normal 3° rotation rate). When increased rotation 

rates were used, the pilots noted that the stick shaker frequently activated but only briefly. The

pilots also indicated that the simulator was controllable at all c.g. locations using both normal

and increased rotation rates. 

In the PFS sensitivity study, each pilot performed takeoffs with either the modified or 

production PFS units. The c.g. was set at 40.5 percent MAC for each takeoff. The pilots reported 

no handling differences between the modified PFS and the production PFS units. 

Safety Board staff and Bombardier also conducted simulation studies to determine how 

the pilot’s elevator inputs during the accident would affect pitch rates at different c.g. 

 NTSB/AAB-04/01 
20

configurations. The simulations indicated that the pilot’s elevator inputs produced a pitch rate of 

5.5° per second at 35 percent MAC and a rate of 10.5° per second at 40.5 percent MAC (the c.g. 

the accident pilot encountered after rotation).

PFS Unit Examinations

The PFS units (model Nos. TY2614 and TY1741) recovered from the airplane were 

examined at TRW Aeronautical Systems, Lucas Aerospace, United Kingdom, under the 

supervision of the United Kingdom Air Accidents Investigation Branch. A visual and x-ray 

examination was performed and no anomalies were noted except for smoke discoloration. No 

anomalies were found during manufacturer-conducted tests before delivery, during acceptance 

tests in Wichita before installation of the units on the accident airplane, or during postaccident 

acceptance testing. 

COMPANY INFORMATION 

Company History and Organizational and Flight Test Structure 

Bombardier was a Canadian manufacturer of ground and water transportation equipment 

before it purchased Canadair on December 23, 1986. The company purchased Learjet Corporation 

on June 29, 1990. Test development activity for the Learjet line continues at the BFTC. 

At the time of the accident, Bombardier Aerospace comprised eight manufacturing plants

located in five cities, two aircraft parts distributions centers, four approved maintenance 

organizations in four cities, and four approved training organizations in two cities. 

At the time of the accident, a manager of flight test operations and safety was assigned to

BFTC operations. His duties included providing administrative operational support to engineering 

flight test personnel, ensuring compliance with U.S. Federal Aviation Regulations and Canadian

Aviation Regulations for pilot currency and qualification tracking, managing flight logs, 

dispatching, and piloting test flights. The manager of flight test operations and safety was the only 

person assigned to the BFTC’s safety department. 

At the time of the accident, the manager of flight test operations and safety reported directly

to the vice president of flight test at BFTC, who in turn reported to the vice president of engineering. 

The vice president of flight test at BFTC was on the same organizational level as the vice presidents

of engineering at the Toronto, Belfast, Wichita, and Montreal operations. He was also on the same

management level with the vice presidents of program management for product development in

Montreal, the director of quality assurance in Montreal, and the vice president of the Tucson 

Completion Center.

37 According to Bombardier, the manager of flight test operations and safety 

 37 According to International Civil Aviation Organization Circular 247-AN/148, Section 3.10, a safety program

“should be administered by an independent company safety officer who reports directly to the highest level of

corporate management.” The Safety Board, the FAA, and industry safety groups have also recommended that the

safety officer be independent and report directly to top management. Safety Recommendation A-94-201 asked the

FAA to require all carriers operating under Part 121 and Part 135 to “establish a safety function, such as outlined in

Advisory Circular (AC) 120-59, “Air Carrier Internal Evaluation Programs.” AC 120-59 stated that an evaluation

program, which includes audits, inspections and evaluations, should be an “independent process that

organizationally has straightline reporting responsibility to top management.” The AC added that “this management

 NTSB/AAB-04/01 
21

currently reports to the vice president of flight test at BFTC and the executive vice president for 

engineering and product development at company headquarters in Montreal. 

Company Flight Test Accident and Incident History 

Before the accident flight, Bombardier and Learjet experienced two fatal accidents 

(including a 1980 accident involving a Canadair CL-600), two nonfatal accidents and one incident. 

On April 3, 1980, a Canadair Limited CL-600 was destroyed during stall testing near

California City, California.38 The pilot was killed, and the copilot received minor injuries. The

flight test engineer was not injured. According to statements from the surviving pilot and flight test

engineer, the flight crew was troubleshooting a noise associated with stalls conducted during 

previous flight test activities. Airplane control was lost during the stall, and the emergency spin

recovery parachute was deployed. According to the copilot and flight test engineer, who were able

to bail out, attempts to jettison the parachute were not successful and airplane control was never

recovered. 

On July 26, 1993, a Canadair CL-600-2B19 was destroyed during lateral and directional 

stability testing near Byers, Kansas.39 The two test pilots and flight test engineer were killed. 

The probable cause of the accident was determined to be the “captain’s failure to adhere to the 

agreed upon flight test plan for ending the test maneuver at the onset of pre-stall stick shaker, and 

the flight crew’s failure to assure that all required switches were properly positioned for anti-spin 

chute deployment. A factor which contributed to the accident was the inadequate design of the

anti-spin chute system which allowed deployment of the chute with the hydraulic lock switch in 

the unlocked position.”

40

On April 25, 1997, a Canadair BD700-1A10 landed wheels-up following avionics testing at 

Toronto, Canada. The test crewmembers were not injured. A Canada Transportation Safety Board 

(TSB) investigation determined that the flight crew did not lower the landing gear and had not

followed a landing checklist. The aural gear warning had been disarmed during the flight test and 

not re-armed by the pilots following the test. 

 [safety] position should be above the level that directly supervises work accomplishment or procedural development 

and should have direct contact with the chief executive officer or equivalent.” Safety Recommendation A-94-201

was listed “Closed—Acceptable Alternate Action” after the FAA issued Joint Flight Standards Bulletins (HBAT 99-

19 and HBAW 99-16) to FAA principal inspectors that provided guidance for the development of a comprehensive 

safety department and the suggested functions, qualifications, and responsibilities for a director of safety position. 38 The description for this accident, LAX80FA073, can be found on the Safety Board’s Web site at 

<http://www.ntsb.gov>. 39 The description for this accident, CHI93MA276, can be found on the Safety Board’s Web site at 

<http://www.ntsb.gov>. 40 As a result of this investigation and an unrelated flight test accident involving a Lockheed C-130, the Safety 

Board issued Safety Recommendation A-94-101, which asked the FAA to inform members of the flight test 

community about the circumstances of these accidents. Specific to the Byers, Kansas, accident, A-94-101 urged that 

“all companies involved in flight test of airplanes with anti-spin parachute systems ... incorporate a design feature 

that would prevent the parachute from deploying if the jaws securing the parachute to the airplane are open.”

According to Bombardier, the spin chute system has been redesigned to prevent the chute’s deployment before it is

secured to the airplane. 

 NTSB/AAB-04/01 
22

On October 27, 1998, a Learjet 45 was destroyed after colliding with a pickup truck 

parked next to the runway during water ingestion testing near Wallops Island, Virginia.41 The 

copilot and flight test engineer received minor injuries. The probable cause of the accident was 

determined to be the “failure of the pilot to obtain/maintain alignment with the water pool, which 

resulted in a loss of control. Factors in the accident were the inadequate preflight planning of the 

flight test facility and the airplane manufacturer which resulted in hazards in the test area and the 

subsequent collision of the airplane with a vehicle.” 

Bombardier also reported a flight test-related incident that occurred on July 21, 2000, when

a Global Express BD-700-1A10 experienced an elevator jam following its first production test

flight. The flight crew used a combination of thrust and pitch trim to maintain airplane control. The 

flight crew managed to free the right-hand elevator and landed at Lester B. Pearson International 

Airport in Toronto, Canada. A company investigation revealed that an unflagged rigging pin was

not removed before the flight.

42

Company Training 

At the time of the accident, Bombardier production and experimental test pilots attended 

initial and recurrent flight training at a company-owned or a commercial flight training facility that 

is structured for operational flying, such as charter and private operations. No test scenarios were

presented during these courses. Three-week initial training comprised 2 weeks of ground school

and 1 week of simulator training. One day of line-oriented flight training was provided during

simulator training. 

Company flight test training is on-the-job, according to Bombardier’s senior engineering test

pilot. Flight test maneuvers are demonstrated to pilots, and the maneuvers are then performed by the

pilot in training. Bombardier sends its test pilots and flight test engineers to a 2-week flight test

short course at a civilian flight test school. Between 33 percent and 40 percent of flight test 

personnel had received military training or had attended a civilian test pilot school before being

hired. 

The company’s chief test pilot at the time of the 1993 Byers, Kansas, accident told Safety

Board investigators that flight test training was conducted as an apprenticeship. He stated that pilots

learned maneuvers and procedure by observing from the jumpseat or second pilot seat. The chief

test pilot stated that pilots did not receive external test pilot training and that they did not use the

company’s simulator for flight test training. 

Postaccident interviews with Bombardier flight test employees indicated that no formal

safety training meetings were conducted. Safety issues were presented during all-hands 

meetings. Several test pilots stated that they were not familiar with details of previous

Bombardier flight test accidents and would like to be provided flight test incident and accident 

information. 

 41 The description for this accident, IAD99FA008, can be found on the Safety Board’s Web site at 

<http://www.ntsb.gov>. 42 The description for this accident, TSB Occurrence No. A00O0150, can be found at the TSB Web site at 

<http://bst.gc.ca>. 

 NTSB/AAB-04/01 
23

Company Flight Test Procedures 

Bombardier’s flight test operational and safety policy manual, Bombardier Flight Test

Standards and Procedures 3000 (BFTC 3000), was published on October 10, 1996, and revised 

(with revision A) on December 14, 1998. Parts of the manual were incorporated into FAA Order

4040.26, “Aircraft Certification Service Flight Safety Program,43 which established flight test 

briefing, risk assessment, and risk management procedures. Neither FAA nor Transport Canada 

regulations required Bombardier to have a flight test policies and procedures manual. 

The 1996 BFTC 3000 manual did not require a test hazard analysis (THA) document, which 

addresses hazards, their causes, their effects, minimizing procedures, corrective action, and relevant 

remarks. Revision A contained provisions for hazard identification and risk reduction. Bombardier’s

chief of flight test operations and safety stated that the document was not used in Bombardier’s

sustaining programs at the time of the accident but that it was a phased-in program that had been

implemented in the company’s developmental (experimental) programs, such as the RJ 700 

program.44

Both documents list risk levels of high, medium, and low for flight maneuvers or flight

conditions. A high risk level indicates a high probability of an incident or accident involving severe

damage to equipment and/or injury to personnel. Approval for high risk flights must be received

from Bombardier’s vice president for flight test or the engineering flight test director. 

High risk test flights include new prototype flight testing. The manual states that such tests

will be defined high risk “until an operation envelope covering stability and control, engine

operation...[has] been defined.” The tests included “all flight testing for the expansion or definition 

of limits appropriate to stability and control, flutter, performance, maximum airspeed and engine 

operation, testing that could result in loss of all engines, flight control failures, high speed ‘upset’

tests, initial stall tests, [and] stall tests with adverse c.g., aerodynamic, configuration, or component 

changes.” High risk test flights also included “evaluation of unproven components in critical 

systems or the airplane in critical environments (e.g. high altitudes, high or low speeds, braking 

systems, flight controls, life support)..., structural demonstrations at limit values, ... takeoff 

performance with actual engine shutdown, maximum brake energy test, maximum rudder sideslips,

high altitude depressurization [or] any flight test, which, in the opinion of the test pilot-in-command 

and/or a representative of the engineering discipline responsible for the flight test to be conducted, 

warrants consideration as high risk.” 

A medium risk level indicates the probability of an incident or accident combined with 

moderate damage to equipment and/or injury to personnel. According to the manual, these tests

“require more than routine supervision.” Such flights must be approved by the Lear/Canadair

program manager or the chief of flight test operations and safety. Medium risk flights include, “loss

of one engine, including fuel starvation due to negative or lateral G, extreme attitudes, testing where

close visual chase is required, flight outside of the current normal flight and/or operational

envelope..., operating at minimum usable fuel [and] intentional single engine shutdowns.” 

 43 FAA Order 4040.26 was initially published in 1997 and was revised on March 23, 2001. 44 The Challenger 604 was considered to be under the sustaining program because the airplane had been

certified. The accident flight was considered experimental because it was to test an unproven change to the airplane. 

 NTSB/AAB-04/01 
24

A risk level of low indicates that there is a low probability of incident or accident combined

with minimal damage to equipment and/or injury to personnel, according to the manual. The risk

assessment authority for these flights is the PIC. 

Bombardier’s safety risk assessment process is described in BFTC 3000 Revision A as 

follows: 

8.5.2 Steps in Deliberate Safety Risk Management 

a. Hazard Identification: Hazard identification begins with the preparation 

of the test requirements document...and [conducting] a preliminary hazard 

analysis. This analysis is a list of hazards that could occur and result in

mishaps/incidents/accidents. This preliminary hazard analysis is developed using 

experience, scenario thinking, archives, and similar techniques. 

8.5.5 The Safety Risk Assessment Process 

a. Aircraft Configuration: All test aircraft will be configured in accordance 

with Bombardier Aerospace, Transport Canada, or the Federal Aviation

Administration directives as appropriate for the conduct of the test.

b. Crew: All flight crews on the test or chase aircraft will be qualified and 

current IAW [in accordance with] BFTC 3000 prior to the start of the test.

c. Briefings: All test personnel will participate in pre test briefings.

d. The Completed Safety Risk Assessment will be briefed prior to each 

flight. The Safety Risk Assessment format will vary IAW program directives.

However, each completed Safety Risk Assessment is required to contain the 

following information. 

1) Decision Authority Signature 

2) Risk Assessment 

3) Hazard Identification (Not required for low risk flights)

45

4) Risk Reduction (Not required for low risk test flights)46

Surveillance of the Bombardier Flight Test Facility 

Under a bilateral agreement with the United States, Transport Canada has direct regulatory oversight

of the BFTC facility. However, there are no Canadian or U.S. regulations specific to the conduct of 

flight test operations. The last Transport Canada inspection of the BFTC facility before the accident

was conducted on November 5, 1999. A full-time, on-sight Transport Canada inspector was not

assigned to the BFTC facility until after the accident. 

 45 According to the BFTC 3000 manual, hazard identification “begins with the preparation of the test 

requirements document,” which includes “a preliminary hazard analysis.” The manual states that the preliminary 

hazard analysis “is developed using experience, scenario thinking, archives, and similar techniques.” 46 The BFTC 3000 manual lists risk reduction measures to be conducted before the flight, including

consideration of whether or not “this configuration (aerodynamic or systems) [has] been flight-tested.” 

 NTSB/AAB-04/01 
25

As part of initial certification and subsequent modification programs, Transport Canada test 

pilots and flight test engineers are involved with BFTC management and flight test crews during

certification tests to validate company compliance. FAA and JAA flight test crews also fly with

BFTC flight test crews to validate Transport Canada certification of new and modified airplanes.

Although not defined as regulatory oversight of the operation, the activities provide and opportunity

to observe company operations, according to Transport Canada. 

The FAA’s MIDO and Wichita Aircraft Certification Office (ACO), located at ICT, provide

oversight for the manufacture and certification of Learjet airplanes manufactured at the Bombardier

Learjet facility in Wichita. The Wichita MIDO also issues special flight authorizations for

Bombardier-Canada airplanes based on limitations developed by Transport Canada. Although the

FAA’s Wichita ACO is located at ICT, the FAA’s ACO in Valley Stream, New York, has certification 

oversight for the CL604 and other aircraft manufactured by Bombardier in Canada. The New York

ACO has no direct regulatory oversight responsibility of Bombardier airplanes manufactured in 

Canada and test flown in Wichita. However, according to the manager of the New York ACO, FAA

certification personnel are authorized to validate Canadian certification test points. 

Transport Canada Postaccident Audit of Bombardier’s Wichita Facility 

After the accident, Transport Canada conducted a Special Purpose Audit at the BFTC from 

October 25 to 27, 2000. The audit report commended Bombardier “for documenting procedures for 

the safe conduct of flight tests [the standards and procedures manual 3000]” but that “the audit 

revealed that the company management does not always enforce the provisions of the manual.” The 

audit report stated that Bombardier project directives authorize specific BFTC engineers to “develop 

and approve developmental and experimental modifications specific to the flight test aircraft that

can have significant effects on safety.” The report noted that “documentation or specific procedures

were unavailable to demonstrate that other engineering disciplines, potentially affected by the 

modification, provided sufficient analysis to support safe operation of the aircraft.”47

In addition, the audit report stated that the “chief of flight operations and safety at BFTC is

an unusual position in that it combines the ‘Safety Manager’ function with that of ‘Operations 

Manager, which due to their functions have conflicting or incompatible roles.” 

The audit report noted that BFTC has a “well documented safety risk management [SRM]

process” but that the SRM process did not address several areas. According to the report, these areas 

included the following: 

a) The risk level of a particular flight test activity is assigned prior to the

expected effect of the minimizing or mitigating procedures. The hazard 

associated with using a[n] SRM tool that assigns risk level without taking 

 47 In a November 27, 2003, letter to the Transportation Safety Board of Canada (forwarded to the Safety Board), 

Bombardier challenged several conclusions and observations contained in Transport Canada’s postaccident audit.

The company stated that it had “challenged Transport Canada ... and provided substantial proof that the subject

documentation and procedures were readily available and that the required engineering oversight for the safe 

conduct of flight testing was beyond reproach.” In addition, Bombardier claimed that the audit “lacked specifics” 

and that “many of its findings were refuted by Bombardier.” Corrective actions were also taken, according to

Bombardier, including having the safety manager report directly to the executive vice president of engineering on

safety issues and to the vice president of flight test on day-to-day issues. 

 NTSB/AAB-04/01 
26

into account the effectiveness of the risk reduction procedures is that the 

residual risk of a test could actually be higher than perceived; 

b) Low risk tests require no risk reduction, or identification of mitigation 

procedures. This is contrary to one of the basic principles of flight test

safety, which is quoted in Section 8.5.1 of BFTC S&P 3000, ‘Accept no

unnecessary risk’; and 

c) Low risk tests are defined as ‘all test flying not described as high or 

medium risk’. There are lists of what are considered high and medium risk 

tests. The implication is that if it is not listed in the high or medium lists,

then it must be low, without any analysis being performed. 

d) The procedures in place have the potential, particularly in situations of 

time pressure, to over rely on the TDS [test definition sheet] generated risk 

analysis. Under such circumstances, further in-depth analysis of the risk

associated with the particular test might be warranted. 

The audit report concluded that “it was evident that the level of activity at BFTC was very

high and is predicted to continue at this pace. The tempo of operations continues to place working 

pressures that have the potential [to] affect flight safety.” 

ADDITIONAL INFORMATION 

The wreckage was released and all retained components were returned to Bombardier 

Incorporated. The FAA, Bombardier and General Electric were parties to the investigation. The 

TSB assigned a technical adviser to the investigation. Transport Canada provided technical 

personnel and resources throughout the investigation, including assistance in FDR/CVR readouts 

and Bombardier simulator tests. 

Normal Takeoff Procedures 

According to the Bombardier Aerospace Challenger 604 Operations Reference Manual, the

PF rotates to 14° at 3o per second after the “rotate” call from the PNF. The same rotation rate is used 

for an abnormal takeoff (engine failure after V1) but with a reduced pitch attitude of 10°. The

rotation rate value listed in the Challenger 604 Operations Reference Manual is based on an 

industry average for transport-category aircraft takeoff profiles. 

Flight Test Safety Standards 

During the investigation, Safety Board staff examined flight test standards and programs

developed by the FAA, the U.S. military, and the civilian National Test Pilot School. FAA

certification test pilots attend an initial 6-week standardization course at a civilian test pilot school 

and receive 2 weeks of recurrent training. The course covers helicopter and fixed-wing flight test

fundamentals, flight test safety, and flight test crew resource management (CRM). According to the

FAA, the majority of FAA test pilots had received formal test pilot training from a military test pilot 

school before being hired, although the FAA also hires test pilots who have at least 1 year of 

 NTSB/AAB-04/01 
27

industry flight test experience. FAA test pilots validate test points that have already been performed 

by airplane manufacturers. 

The aircraft certification flight safety program established in FAA Order 4040.26 requires

FAA management personnel who participate in safety management training to disseminate lessons

learned to those involved in certification and to receive CRM training. The order also formalized 

procedures for the formal assessment of flight test risks and the acceptance of residual risks when 

signing the type inspection authorization or test plan. The order defined risk management as

follows: 

The process by which an assessment is made of the risks involved during a flight 

test, the establishment of mitigating procedures to reduce or eliminate the risks,

and a conscious acceptance of the residual risks. Risk assessment is normally 

done by a safety review process in which a flight test plan is reviewed by project 

and non-project personnel in order to draw out potential hazards and recommend 

mitigating (or minimizing) procedures. Experience has shown that knowledgeable 

non-project personnel who are similarly involved in other projects provide 

valuable contributions to this process. They can identify areas that may have been

overlooked by the project team (aircraft manufacturer vs. limited flight test 

experience), and flight crew currency in both the test method(s) and aircraft type. 

U.S. Air Force Flight Test Center (AFFTC) Instruction 91-5, “AFFTC Test Safety Review

Process,” directs the application of system safety principles to the planning and conduct of all 

AFFTC and other designated test programs. It states that safety planning and technical planning are

integral and that a “smart test team” will interweave technical and safety issues throughout the

project planning process. The document emphasizes the identification and elimination/control of test

hazards, the preparation of safety-related forms that include a THA, and the importance of safety

and technical reviews.

The National Test Pilot School publication, “Flight Test Training: Luxury or Necessity?”

addressed the benefits and efficiency of training for flight test pilots and engineers. This publication

summarized an FAA test pilot’s views as follows: 

In general, on-the-job trained personnel are usually quite good at what they do; 

but their abilities are dependent on what they have been shown in the past. Flight

testers who have learned on-the-job usually demonstrate very little capability to 

move into new areas of testing because they haven’t been taught the fundamental 

philosophy of flight test. This is particularly noticeable in the area of test safety 

and the incremental approach to test flying. 

 NTSB/AAB-04/01 
28

ANALYSIS

General 

The captain and first officer were properly certificated and qualified in accordance with

applicable Federal regulations and company requirements. 

The airplane was operating in accordance with a Canadian flight permit and a special use

authorization issued by the FAA and was properly equipped to conduct flight tests. Examination of 

the flight controls, the modified PFS units, and the airplane’s engines and systems found no 

evidence of pre-impact malfunction. 

Visual meteorological conditions prevailed. Weather was not a factor in the accident. 

Pilot Actions and Weight and Balance Shift 

According to FDR information and calculated performance data, the airplane’s maximum 

pitch rate after rotation was 9.6° per second, an extremely rapid pitch rate which was

approximately three times greater than the average 3° per second pitch rate recommended in the

Challenger 604 Operations Reference Manual. Safety Board staff review of the PF’s previous 

takeoff performance indicated that he had commanded excessive pitch rates during several 

takeoffs in the months before the accident, including 6.5°- and 6°-per-second pitch rate takeoffs 

in the Challenger from Barrow and Fairbanks, Alaska, a month before the accident; a 7.2°-persecond rotation rate on a Challenger test flight on August 16, 2000; and a 8.3°-pitch-rate takeoff in 

a Global Express on September 22, 2000. 

The amounts of fuel in the airplane’s center, three-in-line auxiliary fuel tanks were not

isolated from each other, which allowed fuel to move freely through pipes between tanks,

especially during acceleration and rotation. Postaccident calculations determined that the c.g. 

moved aft as the airplane accelerated down the runway as fuel shifted rearward in the auxiliary

fuel tanks, tail tanks, and wing tanks. By the time the airplane reached a pitch attitude of 13.8°

20 seconds after the start of the takeoff roll, the airplane’s c.g. increased to at least 40.5 percent 

MAC, according to Safety Board staff calculations. Although fuel some migration is normal and

expected in all airplanes, the CL-604’s center fuel tank design allowed for significant fuel 

migration above the range accounted for in the airplane’s certified c.g. range limits. Safety Board

staff also considered a scenario that did not include fuel migration. Simulation testing indicated 

that without the fuel migration factor, the airplane’s c.g. would have been sufficiently forward to 

prevent the airplane from pitching up sufficiently to trigger the airplane’s stall protection system. 

Thus, the aft c.g., including the c.g. change during the takeoff phase, combined with the

high pitch attitude and pitch rate commanded by the pilot, resulted in stall and loss of control. 

Moreover, the aft c.g. and the aggressive pitch control inputs by the pilot eliminated the safety 

margin that the c.g. limit and the lower pitch rate guidance of 3° per second were intended to 

provide. Safety Board staff and Bombardier simulation studies indicated that either restoring the

c.g. margin or reducing the pitch rate to 3° per second would have provided an adequate safety 

margin. 

 NTSB/AAB-04/01 
29

Based on FDR data, flight data of the PF’s previous takeoffs, and postaccident fuel

migration and shift calculations, it is evident that the pilot’s pitch control, combined with 

unanticipated aft c.g. (fuel) shift during acceleration, resulted in an excessive rotation rate and an 

unexpected and faster pitch rate after liftoff, which caused the airplane to stall. The FAA and 

Transport Canada issued ADs after the accident addressing the issue of fuel migration (lowering 

the aft c.g. limit) and the potential for exceeding the airplane’s aft c.g. limit during acceleration 

or climb. 

FDR data indicated that the stick pusher activated twice (following two pitch up 

oscillations) after the airplane’s pitch angle reached the stick shaker and stick pusher activation

thresholds, and that the pilot made elevator inputs to counter the downward pitch angle induced 

by the stick pusher. During this time, the CVR recorded the sounds of stick shaker, aural stall and 

bank angle warnings. Based on this data, it is evident that the second combination of stall, stick 

pusher activation and subsequent up elevator inputs by the pilot occurred at an altitude too low 

for recovery when the airplane was experiencing wide excursions in pitch attitude and roll.

As noted previously, postaccident examination determined that the modified PFS units,

which were to be tested during the flight, were not a factor in the accident. 

Flight Test Oversight

Safety Board staff examined Bombardier’s flight test operations, company procedures, 

and safeguards to minimize risk. At the time of the accident, Bombardier was phasing in a new 

flight test procedures manual, which included significant changes and additions in the areas of

flight test preparation, hazard identification and analysis, and risk reduction. However, the 

changes had not yet been implemented in the Challenger sustaining program. Although the 

Challenger program was defined as a sustaining program because the airplane had received prior 

certification, the flight was nevertheless experimental because it was designed to test a 

component change that affected the airplane’s handling qualities. 

During the investigation, it was determined that the accident flight’s risk assessment was 

subject to several interpretations. For example, the accident flight was assessed as a low risk test 

flight by Bombardier’s manager of flight test operations and safety, who stated that the 

determination was made because the airplane was operating within its c.g. range and because 

“the modification was stabilizing.” A Transport Canada test pilot later came to the same

conclusion. However, an FAA test pilot concluded that the flight was a medium risk flight 

because it involved the modification of a flight control system. This disparity in risk assessment

underscores the importance of a formal safety review and THA standard, especially when there are

competing assessments. Even if the changes to PFS units were considered minor and ultimately

judged not to pose a medium risk, it is noted that the risk assessment was made minutes before the

flight and did not take into account that the changes were to a flight control system that was to be

tested in flight for the first time during a complex maneuver.

Pilot selection and crew pairing are also part of the flight test safety equation. According 

to Bombardier, test flight training is on-the-job. Although on-the-job flight test training is a 

common industry practice, several airplane manufacturers (including Bombardier) and flight test 

 NTSB/AAB-04/01 
30

schools have implemented an incremental approach to flight test training. This approach includes 

a gradual increase in flight test complexity during on-the-job training and the pairing of newly 

hired flight test pilots with an experienced flight test pilot before the new hires are allowed to

conduct test flights as PICs. It is noted that the accident pilot, whose experience was largely in 

routine, entry-level operational and production testing, rather than flight testing, was assigned as

PIC to test airplane control performance and airplane handling qualities in a complex flight test 

maneuver that he had never flown. The copilot, who was an experienced test pilot in other

airplanes, was assigned second-in-command duties to familiarize himself with the Challenger,

not to demonstrate flight test procedures and maneuvers that were unfamiliar to the accident 

pilot. 

During its investigation, Safety Board staff reviewed test flight safety information from 

several sources, including the FAA, U.S. Air Force and the National Test Pilot School. The 

sources recommend developing THA worksheets for test flights, which include information on 

potential hazards, risk minimizing procedures, or emergency procedures. Briefing a test flight 

with a THA helps pilots focus on the specific risks involved in a test flight and helps to minimize 

the risk of complacency. Bombardier did not use these worksheets for preflight test briefings. 

Neither the flight test card nor the preflight briefing for the accident flight called for a 

“build-up” of the flight test maneuver to be flown. A typical build-up for such a maneuver would 

have called for a gradual entry into the maneuver, at lower speeds and at a more stable c.g.

location, before executing the prescribed maneuver at higher speeds and G forces and aft c.g. 

configurations. The preflight briefing also did not include a discussion about test maneuver 

techniques or about what procedures to follow in the event of a problem or failure in the 

modified systems to be tested. Pitch rate targets were also not discussed in the context of an aft

c.g. test flight. Although the accident flight was to be conducted within the airplane’s aft c.g. 

limit, the c.g. was near the aft limit and should have been briefed to increase awareness of pitch 

rate performance in this configuration. 

Safety Board staff review of Bombardier flight data from 50 flights flown by BFTC 

pilots, including several senior test flight and management pilots, indicated that pilots routinely 

commanded pitch rates that were more than double the recommended rate of 3° per second 

during operational takeoffs. Company flight operations data, collected from every Bombardier 

test flight and archived, is not reviewed as part of an overall company flight operations quality

assurance program. Therefore, this high pitch rate practice, and its potential for hazard, was not

identified by senior Bombardier management. 

Finally, despite experiencing three fatal and two nonfatal accidents during product

development, Bombardier did not have a safety manager who reported directly to senior 

management at headquarters in Montreal, did not conduct regular safety meetings, and did not 

maintain a “lessons learned” safety database accessible to flight crews. 

Based on its review of Bombardier’s flight test operations and other relevant safety 

programs, the investigation determines that Bombardier’s oversight of its flight test program was 

inadequate because risk assessment procedures in place for the Challenger program were not 

followed and because a more comprehensive risk assessment program, which would have 

required a more timely and thorough risk assessment of the accident flight, had not been 

 NTSB/AAB-04/01 
31

implemented for the Challenger test program, although it had been used for 2 years in the 

company’s RJ 700 program. Further, it is evident from the investigation that Bombardier’s

operation of its flight test program was deficient because the preflight briefing was inadequate, 

because a relatively inexperienced flight test pilot was chosen for a flight that involved a 

complex maneuver he had never flown (and in an aft c.g. configuration greater that he had ever 

flown), because a build-up for the accident flight was not considered, and because the company 

failed to identify a history of its pilots’ practice of high rotation rate takeoffs, which becomes

even more critical in airplanes configured with aft c.g.’s. Finally, it is evident from the

investigation that Bombardier’s safety program was deficient because the safety manager at the 

time of the accident did not report directly to senior management. However, it should be noted 

that the BFTC safety manager now reports directly to senior management in Montreal and that 

Revision A of BFTC 3000 is now used for the Challenger program. 

Transport Canada and FAA Oversight of Flight Test Programs 

Under the terms of a bilateral agreement, Transport Canada had direct regulatory 

oversight of Bombardier’s BFTC operations involving the company’s Canadian-manufactured 

airplanes, although the last inspection of the facility was conducted nearly a year before the 

accident. Although Transport Canada assigned a full-time inspector to the BFTC facility after the 

accident, there was very little surveillance of the facility’s flight test operations at the time of the 

accident. Further, there are no Canadian or U.S. regulations specific to the conduct of flight test

operations. Neither FAA nor Transport Canada regulations require Bombardier, or other flight 

test operations, to have a flight test policies and procedures manual. 

It is evident from the investigation that Bombardier is developing and using its Flight Test 

Standards and Procedures 3000 manual, but Transport Canada’s audit observation indicated that 

the company did not always enforce the provisions of its own manual. Thus, Transport Canada 

and the FAA are only monitoring a largely voluntary program. The flight test operations and the

corporate safety culture they require would benefit from the adoption of Transport Canada- and 

FAA-approved flight test standards and procedures. It should be noted that Transport Canada is 

currently considering regulations to require the use of an approved flight test operations manual

and is implementing additional procedures to improve regulatory oversight of flight test

operations, including those at BFTC. 

Survival Factors 

The emergency response to the accident site was timely, with two ARFF vehicles and 

three firefighters arriving at the scene within 90 seconds of the crash. However, there were not 

sufficient ARFF personnel equipped with protective gear in the immediate response to fight the 

fires and perform a rescue. The first responders to the scene, two ARFF fire trucks and three 

ARFF personnel, initiated a mass application of water and firefighting agent to extinguish the 

fuel-fed, exterior fire, which had engulfed the fuselage. The firefighters stated that they could

hear the pilots calling for help after the large exterior fires had been extinguished. Two of the

three personnel were occupied in their vehicles with firefighting activities, according to ARFF 

officials. Firefighters stated that additional personnel during the initial response would have 

allowed them to suppress the cockpit fire more quickly. 

 NTSB/AAB-04/01 
 NTSB/AAB-04/01 

32

 

During its investigation of a runway overrun accident involving a McDonnell Douglas 

MD-82 in Little Rock, Arkansas, in 1999,48 the Safety Board examined whether a passenger who 

needed to be rescued from the wreckage would have survived if sufficient ARFF personnel had 

been available to perform a rescue. In a situation similar to the Challenger accident, rescue 

efforts could not be conducted effectively until off-airport firefighters arrived at the scene. 

Although the Safety Board could not determine whether the passenger would have survived if 

more ARFF personnel had been available, it expressed concern that Federal regulations did not 

ensure that ARFF units would be staffed at levels sufficient to conduct simultaneous firefighting 

and rescue activities.49 As a result, on October 23, 2001, the Safety Board issued Safety 

Recommendation A-01-65 to the FAA. Safety Recommendation A-01-65 asked the FAA to 

“amend 14 Code of Federal Regulations 139.319 (j) to require a minimum Aircraft Rescue and 

Fire Fighting staffing level that would allow exterior firefighting and rapid entry into an airplane 

to perform interior firefighting and rescue of passengers and crewmembers.”50

The flight test engineer’s station was located in the middle of the cabin. The flight test 

engineer’s body was found forward near the cockpit bulkhead. He had suffered severe blunt 

force injuries. The flight test engineer’s seat frame was found near his body with the 5-point 

latch buckled. The lap belts were found burned through. Damage to the seat, the seat floor 

mounts and the injuries sustained by the flight test engineer indicate that scenario three, that the 

flight test engineer’s seat failed, is the most likely. Based on seat damage, evidence of seat frame 

separation in overload and the lack of similar separation of instrument racks near his seat, it is 

evident that the flight test engineer’s seat separated during the impact sequence, and that his 

injuries were consistent with a lack of restraint. 

PROBABLE CAUSE 

The National Transportation Safety Board determines that the probable cause of this 

accident was the pilot’s excessive takeoff rotation, during an aft center of gravity (c.g.) takeoff, a 

rearward migration of fuel during acceleration and takeoff and consequent shift in the airplane’s 

aft c.g. to aft of the aft c.g. limit, which caused the airplane to stall at an altitude too low for 

recovery. Contributing to the accident were Bombardier’s inadequate flight planning procedures 

for the Challenger flight test program and the lack of direct, on-site operational oversight by 

Transport Canada and the Federal Aviation Administration. 

48 National Transportation Safety Board, Runway Overrun During Landing, American Airlines Flight 1420, 

McDonnell Douglas MD-82, N215AA, Little Rock, Arkansas, June 1, 1999, Aircraft Accident Report NTSB/AAR01/02 (Washington, DC: NTSB, 1999). 49 The Safety Board had similar concerns during its investigation of an emergency landing of Air Tran 

flight 913 in Greensboro, North Carolina, on August 8, 2000, because of dense smoke in the cockpit. The Safety 

Board concluded that if the passengers and crew had not been able to evacuate, there would not have been enough 

ARFF personnel to enter the airplane and rescue occupants. The description for this accident, DCA00MA079, can 

be found on the Safety Board’s Web site at <http://www.ntsb.gov>. 50 In a February 19, 2002, letter to the Safety Board, the FAA stated that it had asked the ARAC Airports Issue 

Group to create an ARFF Requirements Working Group to examine ARFF staffing levels as part of an overall 

ARAC review of 14 CFR Part 139. On October 17, 2002, Safety Recommendation A-01-65 was classified “Open—

Acceptable Response,” pending results of the ARAC working group and implementation of the recommendation.