NTSB Factual Report

On September 17, 2011, about 1434 eastern daylight time, a North American T-28C, N688GR, registered to and operated by a private individual, collided with terrain during a low altitude aerobatic maneuver at the Eastern WV Regional Airport/Shepherd Field (MRB), Martinsburg, West Virginia. Visual meteorological conditions prevailed at the time and no flight plan was filed for the 14 Code of Federal Regulations (CFR) Part 91 aerobatic demonstration flight. The airplane sustained substantial damage, and the airline transport pilot, the sole occupant, was fatally injured. The flight originated from MRB about 1425.

The purpose of the flight was a 15 minute performance of aerobatic and non-aerobatic maneuvers by 6 pilots of the Trojan Horsemen Demonstration Team (Trojan Horseman) for Thunder Over the Blue Ridge Open House and Air Show at MRB. The accident flight occurred during the single performance of the Trojan Horsemen that day; a single performance of the Trojan Horseman was also scheduled for the following day.

The pilot of the accident airplane was the No. 6 position for the Trojan Horsemen demonstration. As part of the flight, the Nos. 5 and 6 airplanes were to complete an opposing pass, crossing at show center at an altitude of 500 feet with smoke on, with an aileron roll immediately following the pass. After completion of the opposing pass, the accident pilot was to follow the formation with a four-point roll, and rejoin the formation behind the crowd. The accident occurred during the opposing pass maneuver.The pilot of N28XT who was flying in the No. 5 position reported that he and the accident pilot were laterally displaced and flying towards each other. Their flight paths were to cross at 300 feet above ground level, and then both were to perform an aileron roll.

The pilot of N28XT was to roll to the right after crossing, while the pilot of the accident airplane was to roll to the left after crossing. The pilot of N28XT reported that the accident pilot announced their standard callouts of "key" "rolling in," "in sight," "smoke on," "nose up," and "roll up now," but he did not call "smoke off," which was his first indication that something was wrong with the accident pilot. After crossing and before the next pass, he radioed the accident pilot because he did not observe him in the air, but there was no response. Another member of the team also attempted to communicate with the pilot of the accident airplane, but was unsuccessful. The pilot of N28XT flew over the airport and noted movement of fire rescue vehicles, but thought they were responding to a grass fire until he observed the empennage of the accident airplane. He informed the pilots of the other four airplanes of the crash, and joined them in formation. The five airplanes diverted to a nearby airport and landed uneventfully. A postaccident inspection of N28XT revealed no damage. The rest of the team later reported they did not witness the accident sequence prior to ground contact.

A military pilot who witnessed the accident sequence reported seeing a clean separation of the eastbound and westbound aircraft during the opposing pass. It appeared to the witness that both aircraft pitched up about the same time to begin the aileron roll; however, the eastbound aircraft (N28XT) appeared to pitch up slightly higher than the accident airplane. The witness noted that the pilot of the accident airplane initiated a roll to the left, which he described as more consistent with a slow barrel roll rather than an aileron roll. It appeared to the witness that the roll slowed, then stopped as it reached the 90-degree point. The airplane then descended and impacted the ground.

Another military pilot familiar with aerobatic maneuvers reported that he observed the accident airplane following the opposing pass. He described seeing the initiation of an aileron roll, which in his opinion degraded into a barrel roll. From this point, the airplane descended and impacted the ground.

Air traffic control tower personnel reported seeing the accident airplane about midfield toward the west, and it appeared that after completing the loop maneuver, the airplane continued west in a climb then flew nose-first into the ground. An immediate explosion was noted.

The accident occurred during daylight conditions; there were no ground injuries. The team manager, who was flying with the team at the time of the accident, reported there were no birds in the aerobatic box.

PERSONNEL INFORMATION

The pilot, age 54, held airline transport, commercial, and private pilot certificates. At the airline transport level he held an airplane multi-engine land rating, at the commercial level he held an airplane single-engine land rating, and a glider rating at the private pilot level. There was no record of enforcement action or previous accidents or incidents in the FAA database. He held a special issuance third-class Federal Aviation Administration (FAA) medical certificate issued August 30, 2011, with a limitation that the medical was not valid after August 31, 2012. On the application for this medical certificate, he listed a total flight time of 4,800 hours, and 110 hours in the last 6 months.

According to a biography of the pilot on the Trojan Horsemen website, he was a graduate of the United States Air Force Academy, and spent 13 years active duty as an Air Force fighter pilot, flying over 2,500 hours in the F-15 and F-4 aircraft.

A review of FAA Form 8710-7, titled, "Statement of Acrobatic Competency" issued to the pilot on June 1, 2010, with an expiration of December 31, 2011, indicated an altitude limitation of 250 feet, in T-28 airplanes, with a maneuver limitation of "solo aerobatics both rolls and loops."

One of the team members reported the accident pilot told him a week earlier that he had a sinus infection and took a "Z-Pak," and thought the pilot was recovered. Team members who were with the pilot the previous day for a practice session, that same evening, and the following day up to and including the accident flight reported he was in good spirits.

Additionally, one team member, who is an anesthesiologist, reported that the accident pilot seemed "OK," and he was not personally aware of the pilot's reported sinus infection.

According to the NTSB Medical Factual Report, review of the pilot's certified medical file from the Federal Aviation FAA Aerospace Medical Certification Division revealed his 1st third-class medical was issued in 1976, and following that he routinely had second or third class medical certificates issued without limitations; however, in 2003, he was hospitalized for a heart attack. The cardiac evaluation performed during that hospital admission revealed extensive coronary artery atherosclerosis and he underwent urgent four vessel coronary artery bypass surgery. By May, 2004, one of the grafted vessels was no longer patent (open). Based on thallium stress testing, this meant that an area of the inferior wall of the heart had "reversible ischemia" or insufficient arterial flow with exercise due to stenosis (narrowing) in the feeding artery. Because of its small caliber size and the extent of atherosclerotic disease in the artery in question, it was deemed ineligible for further intervention with re-grafting or angioplasty. The plan was to treat his cardiac risk factors "aggressively". In November, 2004, the pilot underwent repeat thallium stress testing that showed some of the previously "reversible" area was now a completed infarct, with a remaining "medium area" of reversible ischemia nearby.

In 2005, he applied for a third class medical certificate. On the application he reported being treated with medications including a beta blocker, aspirin, and several lipid lowering agents. Included in this application were extensive medical records from the previous cardiac events and evaluations and a medical exemption petition (operational questionnaire), also known as FAA form 8500-20. On this form, the pilot requested medical certification to be pilot in command of single or multi-engine land based fixed wing aircraft, flying privately with altitudes up to 9,000 feet in daylight, night, and instrument conditions that might be in high density traffic metropolitan areas. On this form, the pilot did not check multiple options under section 2, types of operations, which includes in part aerobatics. After review of the submitted documents, the FAA issued the pilot a third class medical certificate under "special issuance": good only for one year and with specified further requirements for annual stress testing and triannual thallium stress testing. It also contained a warning to the pilot that under the Code of Federal Regulations, Title 14 that "operation of aircraft is prohibited at any time new symptoms or adverse changes occur or if you experience side effects, or require a change in medication." The pilot was not required to notify the medical certifying body of a change in the type of flying he was performing, nor was he required to complete a new FAA Form 8200-20, Medical Exemption Petition (Operational Questionnaire) indicating the type of flying he expected to perform during each special issuance period.

In 2007, repeat thallium stress testing showed the same area of reversible ischemia. According to his cardiologist, the previously fixed anterior wall defect, indicating a completed myocardial infarction had "healed" on the 2007 scans. In July, 2007, the pilot requested review for an upgrade to second class medical certificate. A third class certificate was issued by the Aviation Medical Examiner, pending FAA cardiology review. In 2008, the pilot again underwent thallium stress testing, showing "minimal" peri-infarct reversible ischemia and what was thought to be a remote, non-transmural inferior wall defect. At this point, he was officially diagnosed with type II diabetes, but was treated with diet alone. His Hemoglobin A1C level, a measure of glucose control over several weeks, was minimally elevated at 6.2% (

In 2009, the pilot's Hemoglobin A1C reached 7.2% but no further treatment was initiated. His routine exercise stress testing was considered negative in both 2009 and 2010. His A1C in 2010 was 6.9%. On 8/23/2011, he underwent repeat exercise stress testing, which was unremarkable. His A1C was 7.5% and his lipids continued to be in good control on medication. The pilot's last medical certificate was issued in the third class on 8/30/2011.

Two pilot logbooks were located and examined. The first pilot logbook began with an entry dated May 17, 2007, and the second logbook ended with an entry dated September 15, 2011. A hand written note above the "Total Duration of Flight" column of the first pilot logbook depicted "Hobbs." Based on that hand written note, the elapsed hour meter time from the first entry of the first logbook to the last entry of the last logbook was 324 hours. In the 90 days prior to the accident flight, the pilot logged an elapsed time of 27 hours, and in the 30 days prior, he logged an elapsed time of approximately 6 hours. Paperwork located in the wreckage indicated his last flight review occurred on January 15, 2010.

AIRCRAFT INFORMATION

The airplane was manufactured in 1958 by North American as model T28-C, and was designated serial number 140581. At the time of the accident, it was powered by a Curtiss-Wright R1820-86B 9-cylinder radial engine rated at 1,425 horsepower and equipped with Hamilton Standard 3-bladed constant speed propeller.

Review of the maintenance records revealed the airplane was last inspected in accordance with a condition inspection on March 4, 2011. The airplane total time and hour meter reading at the time of the inspection were reported to be approximately 9,803 hours and 950, respectively.

Though the hour meter was damaged during the impact sequence, the pilot logged the hour meter reading in a section of his pilot logbook. His last logged flight on September 15, 2011, ended with an hour meter reading of 1017.0, or an elapsed time of approximately 67 hours since the condition inspection was signed off as being completed.

The accident pilot was a co-owner of the airplane since May 17, 2007.

METEOROLOGICAL INFORMATION

A surface observation weather report taken at MRB at 1435, indicated the wind was from 130 degrees at 4 knots, visibility was 10 miles, and overcast clouds existed at 7,500 feet. The temperature and dew point were 16 and 8 degrees Celsius, respectively, and the altimeter setting was 30.39 inches of Mercury.

COMMUNICATIONS

The pilots of the aerobatic demonstration team were communicating using discrete frequency 122.825 MHz, which was monitored by the airshow boss. At the time of the accident, that frequency was not recorded in the air traffic control tower.

AIRPORT INFORMATION

MRB is a joint-use military and civilian airport with a single runway, designated 08/26, which is 7,815 feet in length and 150 feet in width. The airport elevation is 565 feet, and it is equipped with a control tower manned under contract to FAA.

The airport is also equipped with airport surveillance radar. The radar was operational on the accident date and recorded the accident flight. The military side of the airport is equipped with a surveillance camera located on the south side of the east/west oriented runway. The surveillance camera captured video of the practice flight the day before and also of the accident flight. The surveillance video was retained by NTSB and submitted to the NTSB Vehicle Recorder Division for analysis.

Personnel who planned to fly at the airshow, including the accident pilot, signed a certificate of waiver. The certificate of waiver allowed deviation from FAR's 14 CFR Part 91.117(a) and (b), 91.119 (b) and (c), 91.127, 91.129, 91.155(a), 91.303(c) (d) and (e). Additionally, 66 special provisions were stipulated. The stipulations indicated in part that pilots who performed aerobatics must possess a valid FAA Form 8710-7, titled Statement of Acrobatic Competency, and all limitations on the form would be adhered to, including altitude restriction, for the entire performance.

FLIGHT RECORDERS

The airplane was not equipped, nor was it required to be equipped, with a flight data recorder or cockpit voice recorder. However, it was equipped with a JP Instruments, Inc., EDM-700 (EGT-701-9C) unit; a panel-mounted gauge which monitored and recorded up to 24 parameters related to engine operations. The parameters recorded for the accident airplane and engine included battery voltage, cylinder head and exhaust gas temperatures for all 9 cylinders, and oil temperature. The unit was removed from the airplane during the postaccident investigation, and shipped for readout to the NTSB Vehicle Recorder's Division, located in Washington, D.C.

Examination of the component at the Vehicles Recorders Division revealed that although the component was impact damaged which prevented normal downloading of data, the electrically erasable programmable read-only memory (EEPROM) was removed from the circuit boards and raw-data binary readout of the chips was obtained using a EEPROM programmer. The data was then recovered using information provided by the units' manufacturer.

The recorded data downloaded from the unit contained approximately 21 hours of data over 17 power cycles. The accident flight was the last flight of the recording and the recorded data consisted of approximately 41 minutes. Review of the data for battery, cylinder head temperature, exhaust gas temperature, and oil temperature revealed no substantial change in data at any of the parameters, which recorded every 6 seconds. The Specialist's Factual Report and corresponding downloaded tabular data is included in the NTSB public docket for this case.

WRECKAGE AND IMPACT INFORMATION

The initial impact point was located south of the south side of runway 08/26, near the approach end of runway 26, at 39 degrees, 23 minutes, 56.2 seconds north latitude and 077 degrees, 59 minutes, 23.0 seconds west longitude, and contained debris consisting of the airplane's tail hook. The energy path was oriented on a magnetic heading of approximately 350 degrees, and extended approximately 447 feet between the initial impact point and the restin

NTSB Probable Cause

The pilot's impairment or incapacitation that occurred during a low-altitude aerobatic maneuver due to complications from a recent heart attack, resulting in his inability to maintain control of the airplane. Contributing to the accident was the Federal Aviation Administration's willingness to allow an airman with well-documented, severe coronary artery disease to perform high-risk, low-altitude aerobatic maneuvers.