N138BF

HISTORY OF FLIGHT

On April 26, 2003, at 1005 central daylight time, a Sino-Swearingen Aircraft Corporation (SSAC) SJ30-2, N138BF, serial number 002, was destroyed when it impacted terrain near Loma Alta, Texas. The certificated airline transport pilot was fatally injured. Visual meteorological conditions prevailed for the flight, which departed on an instrument flight rules flight plan from San Antonio International Airport (SAT), San Antonio, Texas, at 0911. The local test flight was conducted under 14 CFR Part 91.

At the time of the accident, the airplane was undergoing flutter testing for Federal Aviation Administration (FAA) type certification. SSAC Report 30-2222, "Flight Flutter Certification Test Plan for SSAC SJ30-2," delineated the flutter testing requirements, which included the Federal Air Regulation (FAR) Part 23.629 requirement that the airplane be demonstrated to be free from flutter, control reversal, and divergence up to the "demonstrated flight diving speed" (Vdf/Mdf). The testing was to be conducted in two phases, with the first phase planned to clear the airplane to its "maximum operating limit speed" (Vmo/Mmo) of 320 KCAS/Mach 0.83, and the second phase, to clear it to its Vdf/Mdf of 372 KCAS/Mach 0.90.

Phase 1 flutter testing had been successfully completed. The first flutter mission of phase 2, flight test number 230, was flown one day before the accident flight, with the same pilot onboard. The objective of that flight was to complete flutter test points 1-12 (Mach 0.844) and 1-13 (Mach 0.864). Test point 1-12 was completed, and subsequently, the airplane went into a uncommanded roll to the left, which the pilot recovered from. Afterwards, during test point 1-13, a discrepancy was noted between the pilot's displayed airspeeds and those reported by a chase plane pilot, so the pilot terminated the flight.

After the flight, the pilot realized that he had incorrectly set up the airspeed display in the test airplane, and was flying faster than his airspeed indicated. In addition, the pilot reported, that during the flight, he had felt a "rumble" in conjunction with the left roll. In his notes, he had written, ".855", and immediately below that, "Abrupt LH Roll [space] Rumble", and beneath that, "Rudder Input?"

According to the project's flutter consultant, a Designated Engineering Representative (DER), a possible explanation for the rumble was Mach buffet. However, to help confirm there wasn't an in-flight mechanical problem with the airplane, flight test personnel assigned a second SSAC pilot as a backseat chase plane observer for the next (accident) flight, flight test number 231.

The chase plane was a contracted Northrop T-38 jet, N638TC, with a pilot and the second SSAC test pilot onboard. The accident flight was also being monitored in a telemetry van in Rock Springs, Texas, by the flutter consultant and three SSAC personnel.

Prior to the test flight, a mission briefing, led by the accident test pilot, was conducted via conference call between the San Antonio-based personnel and the telemetry van personnel. According to a briefing participant, all of the flight test cards were covered, "including the test limitations, test set-up, test points, weight and balance, airspace operational considerations, aircraft limitations, maintenance actions since last flight, instrumentation status, and chase aircraft procedures." A number of witnesses also noted that the test points briefed were 1-14 (Mach 0.884), and 1-15 (Mach 0.894) if conditions permitted.

An "SSAC Flight Briefing Guide" was also utilized, which included a review of hazard analyses, and abnormal/emergency procedures. During the briefing, the test pilot stated that he was responsible for safety of flight.

The flutter consultant also stated that he had, during previous discussions, advised that for the purpose of flutter testing, if the pilot ran out of aileron/elevator trim, the tests could still be completed, even if the pilot had to hold aileron/elevator force to steady the airplane. He further stated, however, that the continuance of the testing would never override the pilot's decision as to whether the control forces were unacceptable or hazardous.

According to the flutter consultant, after takeoff, the accident airplane climbed to 39,000 feet, and prepared for a shallow dive along an easterly track for flight test point 1-14. A telemetry lock was then obtained. However, when the airplane reached indicated Mach 0.875, the test pilot called "Mark" on the radio. [An optional test point "14A" (Mach 0.874) was listed on the flutter test card; however, on the previous day's flight, it had been crossed out.] After the "Mark" was received, the pilot initiated a single pulse input to the elevator. After checking the telemetry strips, the consultant then gave a "Go" for a single pulse to the aileron, followed by another "Go" for a single pulse to the rudder. Telemetry van personnel noted that all the modes excited were "well damped."

Telemetry van personnel also reported that after the pulses were completed, the test pilot stated that the uncommanded roll to the left (which was experienced on the previous flight), did not occur. There was also no mention of a rumble. In addition, the chase plane pilots confirmed that there were no mechanical anomalies evident on the accident airplane.

The flutter consultant further stated that the accident airplane subsequently turned back to the west and began to climb back to 39,000 feet to prepare for the [easterly] dive to the 1-14 point. Discussion between the pilot and telemetry van personnel included the fact that the 1-14 point might be the last one of the mission due to fuel concerns, particularly for the chase plane.

Following telemetry lock, the airplane began a shallow dive. At indicated Mach 0.884, the pilot called "Mark." Each control surface was again pulsed by the pilot, and the responses were again "well damped."

Following the final pulse, the pilot was cleared to the next test point, 1-15 (indicated Mach 0.894), "if flight conditions permitted the test pilot to do so." However, the pilot did not acknowledge the clearance, but instead, reported that the airplane was rolling to the right, and he couldn't stop it.

In a written statement, the chase plane pilot confirmed that after the 1-14 test point had been completed, the test pilot was cleared to accelerate to the 1-15 test point, if able. At that time, the accident airplane appeared to be in a shallow right bank with the chase plane less than 500 feet above and 500 feet behind it. According to the chase plane pilot, "very soon thereafter," about 30,000 feet, the accident airplane began rolling to the right. The rolling maneuver appeared to be stable, and continued unchanged until ground impact. The accident airplane appeared to remain intact throughout the event, and no parts were seen departing the airframe. After the accident airplane began to roll, and the test pilot stated that he couldn't stop it, the chase pilot called, "get out" twice. The accident pilot responded that he couldn't get out, that there were too many "g's."

The second SSAC test pilot, who had been in the back of the chase plane, also reported that the accident sequence began after the completion of the 1-14 test point. During the sequence, the chase plane was not close enough to observe the accident airplane's control positions; however, the second SSAC test pilot observed the accident airplane's nose to be "a little low," and in an approximately 30-degree right bank after test point 1-14 was completed. A few seconds later, the accident airplane entered a "barrel-roll type maneuver" to the right, then continued to roll, and increased its dive angle until ground impact.

When the second SSAC test pilot saw the first roll, his first thought was, "what did he do that for?" Then he saw that the accident airplane "came around and made another barrel roll. It was not around a point like an aileron roll; and it was not real fast; it looked lazy." The chase pilot then mentioned the roll to the accident pilot, who replied that he couldn't stop it. The accident pilot did not say anything further about how the airplane was performing, or what he was experiencing.

At some point during the sequence of events, the accident pilot transmitted information about the flight controls and/or aileron trim; however, witness accounts differed on what and when it was transmitted. According to the chase plane pilot, the accident pilot stated, "I can't let go" after he was cleared to test point 1-15. The flutter DER stated that the accident pilot advised he "could not release the wheel" shortly after the 1-14 aileron pulse, and a telemetry engineer, who was calling out airspeeds to the DER, stated that the accident pilot reported, "full aileron trim and I can't let go" when the accident airplane had accelerated to Mach .881, prior to the 1-14 pulses.

PERSONNEL INFORMATION

-- Accident Pilot --

The accident pilot held an airline transport pilot certificate, with ratings for the Boeing 707, 727, and 747, and Airbus 300. He also had combat experience in the Vought F8J Crusader, and served a total of 30 years as an active duty and reserve Naval officer.

According to the pilot's resume, dated July 2, 1996, he had 12-13 years of flight test experience prior to joining SSAC, including experience at LTV (Ling-Temco-Vought) Aerospace, Douglas Aircraft, the U.S. Navy, and General Electric. He was not a test pilot school graduate.

Between 1966 and 1969, the pilot flew A-1 Skyraiders, then transitioned to the A-3 Skywarrior. He subsequently flew EKA-3B conversion flights from a depot level rework facility, and later, F-8 Crusader and F-4 Phantom acceptance flights.

In 1969, the pilot qualified as a Boeing 727 flight engineer for a major airline. Later that year, when he was furloughed...