ERA10FA404

The pilot’s loss of control of the airplane during low-airspeed airwork and his failure to promptly recover the airplane from the aerodynamic stall, which resulted in a spin. Contributing to the accident were the pilot and certified flight instructor’s intentional operation of the airplane for the purpose of performing instructional airwork with only a throw-over control yoke installed and the pilot’s lack of recent flight experience in the airplane make and model. Contributing to the lack of accurate performance data (including the air minimum control airspeed) for the modified airplane was the lack of guidance by the Federal Aviation Administration for an installer of a supplemental type certificate (STC) modification to determine the interrelationship between all STCs incorporated into an aircraft.

The pilot had previously owned the accident airplane about 22 years ago, and it was subsequently modified under a supplemental type certificate (STC) that installed vortex generators (VGs), which decreased the airplane’s air minimum control airspeed (Vmca) from 81 knots to 74 knots. Another subsequent STC modification, STC SA1762SO, installed more powerful engines, different propellers, winglets, and modified engine nose cowlings. STC SA1762SO took into account a change to only the original type design and increased the airplane’s Vmca to 87 knots; however, the airplane’s airspeed indicator remained marked to indicate a Vmca of 74 knots. A representative of the current holder of STC SA1762SO reported that, to his knowledge, no flight testing was performed on the accident airplane or any similar make and model airplane to determine the interrelationship between his company’s STC and the previous STC. Therefore, the actual performance data for the accident airplane, including the Vmca, were unknown. However, the Vmca for the accident airplane was likely higher than the 74-knot Vmca marked on the airspeed indicator. The pilot purchased the airplane 4 days before the accident and performed three full-stop landings 2 days before the accident to get current. An individual familiar with the pilot believed that the pilot had not previously flown a reciprocating-engine-equipped airplane in about 3 years. Due to the pilot’s recent purchase, an insurance company broker “suggested” that the pilot obtain a multiengine instrument proficiency checkride; a Federal Aviation Administration (FAA) designated pilot examiner acting as a certified flight instructor (CFI) was on board for the accident flight. The CFI did not have an exemption from 14 Code of Federal Regulations 91.109(a) to give instruction in an aircraft equipped with a throw-over control yoke. According to uncorrelated radar data, after departure, the flight proceeded north-northwest and climbed to 3,600 feet where two 360-degree nearly level turns to the left were made, followed by a 360-degree turn to the right. The airplane then proceeded north-northwest and climbed to 4,200 feet briefly with the ground speed decreasing to 127 knots, then it descended to 3,900 feet and remained at that altitude, at which heading changes occurred, and the ground speed decreased to about 71 knots. Witnesses reported seeing the airplane flying level before it descended in a left spin and impacted a house. The only major components of the airplane that were not extensively heat damaged consisted of the outer section of the left wing and one cargo door, both of which were found in close proximity to the house. Both engines and their accessories and both propellers were extensively heat damaged. Although the right engine-driven fuel pump drive coupling was found fractured, this likely occurred during postaccident rotation of the crankshaft in order to facilitate removal of the propeller. The extent of the heat and impact damage to the airplane limited the airframe and engine testing that could be performed; however, there was no evidence of preimpact failure or malfunction on the observed components. Based on the airplane’s decreasing airspeed and nearly level altitude, the pilot was likely performing either imminent stall or simulated loss of engine power airwork before the airplane aerodynamically stalled and then entered a spin. Because the airplane was equipped with only a throw-over control yoke, the CFI had limited ability to assist in the recovery of the airplane. Although it was not possible to determine which low-airspeed maneuver was being demonstrated, one scenario that is consistent with the radar data evidence (and is typically performed during multiengine checkrides) is the Vmca demonstration, which requires a power reduction on one engine(and is consistent with the witnesses' descriptions of "sputtering" engine sounds). If the pilot were performing a Vmca demonstration, it is possible that the airplane began to lose directional control earlier than expected because the actual Vmca of the airplane with multiple STC modifications was unknown, and the airspeed indicator was improperly marked. Although the limitations and conditions section of STC SA1762SO stated that the installer must determine that the relationship between that STC modification and any other previously approved modifications “will not produce an adverse effect upon the airworthiness of that airplane,” the investigation found that the FAA does not provide any guidance to an installer to help determine the interrelationship between multiple STCs. As a result of this accident, on December 29, 2011, the FAA issued Airworthiness Directive (AD) 2011-27-04 that requires an inspection for airplanes equipped with STC SA1762SO and that specifies corrective action, if applicable, to ensure that the airplanes have the correct Vmca marking on the airspeed indicator, taking into consideration other STC modifications. AD 2011-27-04 is available from the FAA’s website at <http://www.faa.gov>.

HISTORY OF FLIGHT On August 7, 2010, about 0920 eastern daylight time, a Beech 58, N28MR, descended into a house near Saltsburg, Pennsylvania. The certificated commercial pilot and certified flight instructor (CFI) were killed. The airplane sustained substantial damage and the occupied house was destroyed, while an occupant of the house was not injured. The airplane was registered to Sataire LLC, and operated by the pilot under the provisions of 14 Code of Federal Regulations (CFR) Part 91 as an instructional flight. Visual meteorological conditions prevailed at the time and no flight plan was filed. The flight originated from Arnold Palmer Regional Airport (LBE), about 0908. According to a transcription of communications with the LBE Air Traffic Control Tower, and a certified copy of the voice tape, an occupant of the airplane contacted ground control which was combined with the local control position and requested taxi clearance from the east ramp to runway 23, with a departure to the northwest for "…some airwork." The flight was cleared to taxi to runway 23, and review of the voice tape revealed the same occupant contacted local control and advised the controller that the flight was ready to depart. The local controller cleared the flight for takeoff from runway 23 with a right turn approved. That transmission was acknowledged by the occupant; there was no further recorded communications from the accident flight. One witness who was outside reported hearing sputtering sounds from an engine, then observed the airplane flying in level flight in a westerly direction. She then noted that the wings were teeter-tottering followed by seeing the nose pitch down. She then saw the airplane in a spin descending in a nose-low attitude. Another witness who was also outside reported hearing spitting and sputtering sounds from the engine and looked up seeing the airplane flying in level flight in a northwesterly direction with little white puffs of smoke coming out of both engines. The witness attributed the smoke to be coming from the sputtering engines, but once the engines restarted 3 or 4 seconds later, the smoke stopped, but the spitting and sputtering started again followed by the puffs of smoke. The witness reported the engines stopped operating and to him it appeared that the airplane slowed, followed by the airplane drifting to the left side and left wing dipped down. The airplane started a 45 degree nose and left wing low descent spinning to the left. The witness described seeing pencil streams of smoke trailing both engines during the descent with the streams twisting behind the airplane like licorice candy. Several witnesses reported hearing abnormal engine sounds, followed by seeing the airplane in a left spin, or spiraling down which continued to the ground. One witness heard the engine quit and restart several times, then rev up loudly after the third restart. Several witnesses reported to the Federal Aviation Administration (FAA) inspector-in-charge seeing smoke or vapor trailing both wings. One witness reported seeing the airplane in a slow left spin, which continued until the airplane went down below the tree line. The witness then heard the impact and saw rising smoke. The occupant of the house who was in the basement reported he was asleep on a couch and was awakened by a violent noise. House debris was blown into the basement, and he immediately got up, got his dog, and went outside where he called 911 to report his house was on fire, which burned incredibly fast. While outside he noticed a portion of a wing beyond the edge of the roof, and could also distinguish a "chrome propeller." Uncorrelated radar data for airplanes transmitting VFR transponder code (1200) at the departure airport and surrounding area for the approximate takeoff and accident times was provided by the FAA. Review of the supplied data revealed at 0909, or approximately 1 minute after the flight was cleared for takeoff, a target at 2,000 feet mean sea level (msl) was noted approximately 240 degrees and 0.6 nautical mile from the departure end of runway 23. The target proceeded in a north-northwesterly direction and climbed to approximately 3,600 feet msl. At approximately 0914, the radar data indicates the target turned 360 degrees to the left while maintaining approximately 3,600 feet msl; the turn took slightly less than 2 minutes. The radar data indicates the target briefly resumed the north-northwesterly heading, before turning 360 degrees to the left again, while maintaining approximately 3,600 feet msl. The second turn took less than 1 minute and at the completion of the turn, the target briefly continued north-northwesterly before turning 360 degrees to the right while maintaining approximately 3,600 feet msl. The right turn took approximately 1 minute to complete, then the target was noted proceeding on the north-northwesterly heading. While continuing on that heading the target climbed to a maximum altitude of 4,200 feet msl which occurred at 0919:31, and the groundspeed slowed to 137 knots. The target remained at that altitude until 0919:44, during which time the groundspeed was recorded to be 127 knots. The next radar target with altitude and groundspeed at 0919:45, indicates the altitude was 3,900 feet, the heading was 292 degrees, and the groundspeed was 113 knots. The radar data indicates that between 0919:45, and 0919:53, the altitude remained constant at 3,900 feet, the groundspeed decreased from 111 to 81 knots, and the heading changed from 290 to 194 degrees. The next and last radar target at 0919:57, indicates the airplane was at 3,900 feet, the groundspeed was 70 knots, and the heading was 323 degrees. The last radar target was located at 40 degrees 28 minutes 55.59 seconds North latitude and 079 degrees 30 minutes 58.47 seconds West longitude, or approximately 137 degrees and 900 feet from the accident site location. PERSONNEL INFORMATION The pilot, age 65, held a commercial pilot certificate with rating(s) airplane single and multi-engine land, instrument airplane. On August 3, 2007, a notice of disapproval of application was prepared indicating that during a practical test in a level D simulator for a Cessna 510 airplane, the pilot failed several areas including powerplant failure during takeoff. He received 6.0 hours of additional training and on August 14, 2007, he obtained a type rating in a Cessna 510 airplane with a limitation that a second-in-command was required because he did not meet the single pilot proficiency requirement. There were no other records of failures for any pilot certificate or additional rating(s). He held a second class medical certificate with no medical restrictions or limitations issued November 23, 2009. On the application for his last medical certificate he listed 3,200 hours as his total flight time. There were no records of enforcement action or previous accidents or incidents in the FAA database. Three pilot logbooks were presented documenting his flight time from May 16, 1967, to the last entry in logbook No. 3 dated November 5, 1999. Although a current pilot logbook was not located, copies of pilot logbook pages, and spreadsheet pages were provided to NTSB documenting his flight time from July 15, 2006, to January 3, 2010. Review of the logbooks, copies of pilot logbooks pages, and spreadsheet pages reflect flights in multi-engine airplanes consisting of Hawker Beechcraft 58 and B60, Cessna 340 and 510 (N75ES), and Piper PA-60. He logged a total multi-engine flight time of approximately 1,516 hours, of which approximately 560 hours were accrued in the accident make and model airplane between July 21, 1983, and March 21, 1990. The CFI, age 66, was a FAA designated pilot examiner (DPE), and held an airline transport pilot certificate with airplane multi-engine land and instrument airplane ratings. He also held commercial and certified flight instructor (CFI) certificates. 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