N688GRNorth American T-28C · 1958

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.

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.

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.

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.

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.

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.

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.

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 resting point of the center portion of the cockpit. The initial impact site was about on the category III centerline, about 1,707 feet from the nearest point of the spectator area, and the majority of the wreckage came to rest between the category 1,2, and 3 centerlines, with the engine coming to rest just north of the category 3 centerline.

Major components located along the energy path were documented as to their location and mapped by the West Virginia State Police. The components were numbered and identified as 1 – engine; 1A – inboard propeller piece and crankshaft gearing/propeller hub; 2 – accessory housing; 2A – propeller; 3 – governor; 3A – propeller piece; 4 – right wing; 4A – propeller piece; 5 – left wing; 5A – actuator; 6 – main wreckage/cabin; 6A – tail hook; 7 – left wing outer panel; 7A – pitot tube; 8 – outboard right wing and one engine cylinder; 9 – vertical stab and right horizontal stab/elevator; 10 – nose landing gear; 11 – inboard left elevator; 12 – right flap; 13 – left flap; 14 – left horizontal stab; 15 – rudder; 16 – cylinder; 17 – cylinder; 18 – outboard right elevator; 19 – propeller blade; and 20 – propeller hub.

All major components of the airplane were accounted for along the wreckage path, including propeller blades, left and right elevators, left and right horizontal stabilizers, left and right wings, and the engine. The main wreckage consisted of the fuselage, which exhibited significant impact damage, and was located at 39 degrees, 23 minutes, 59.2 seconds north latitude and 077 degrees, 59 minutes, 26.0 seconds west longitude. The wreckage was recovered for further examination and the runway was opened on September 18, 2011, at 1650 eastern daylight time.

Examination of the wreckage following recovery revealed the fuselage was fractured by the front seat area and also in the area of the vertical fin. The aft empennage upper crown was fractured 6 feet aft of the joint near the aft canopy actuator. The vertical stabilizer was structurally separated and the rudder was separated from the vertical stabilizer; the rudder trim tab remained attached to the rudder. The left horizontal stabilizer and section of left elevator were separated, and the right horizontal stabilizer was separated at the forward fitting. The right horizontal stabilizer was displaced up approximately 45 degrees. Examination of the flight controls for roll, pitch, and yaw revealed no evidence of preimpact failure or malfunction. Additionally, examination of the structural fractures revealed no evidence of preimpact failure or malfunction. Examination of the flap position valve revealed the arm was fractured; therefore, no determination could be made as to the flap position at the time of the accident. Both speedbrake actuators were symmetrically extended approximately 18 inches, which equated to full extension.

Examination of the left wing revealed it was fractured in 2 major pieces, and the flap was fractured in 2 major pieces. The wing was fractured at the inboard edge of the aileron. The landing gear was in the retracted position, and the aileron and aileron trim tab remained connected to their respective attach points. The aileron trim tab was in an approximately neutral position. Fire damage was noted to the fuel tank just outboard of the main landing gear.

Examination of the right wing revealed the outer 9 feet 8 inches were separated. The aileron with trim tab remained attached. The aileron trim tab was also in the neutral position. Both aileron cables remained connected at the bellcrank near the control surface. One cable had a ball on the opposite end, and the other cable exhibited tension overload approximately 8 feet 8 inches inboard from the bellcrank. The landing gear was separated from the wing. The flap was separated and found in 2 pieces. Fire damage was noted to the inboard section of the wing.

Examination of the cockpit revealed the aileron trim tab indicator was 1 degree left wing low, while the pitch and rudder trim positions could not be determined. Although both throttle quadrants were structurally separated from the airplane, a gouge on the right side of the throttle slot of the aft seat throttle quadrant was noted. The gouge was consistent with the width of the throttle arm and was located about 1.25 inches forward of the aft end of the throttle slot. Examination of the front seat throttle quadrant revealed the propeller and mixture controls were in the full forward positions and bent to the right. Examination of the pilot's front windshield revealed no evidence of bird remains. The pilot's restraint as first viewed was unlatched; however, inspection of the restraint revealed the webbing of the shoulder harness of 1 strap exhibited a tear. The restraint was tested and found to buckle and un-buckle satisfactorily. Examination of the rear seat revealed the restraint remained buckled; however, the parachute was found outside of the seat. The restraint was unlatched and latched and found to operate satisfactory.

Two instrument panels were identified among the main wreckage. Both exhibited significant impact damage, and most instruments were separated from their positions. The first observed instrument panel contained a flap position indicator which measured off-scale in the "flaps up" position, fuel quantity indicator, turn coordinator, altimeter, and S-Tec autopilot mode selector. The fuel quantity indicator and turn coordinator were damaged during impact, and the corresponding needles were missing from the instrument faces. The altimeter also displayed impact damage, and was missing the hundred-foot needle; the Kollsman setting was 29.89 inches of mercury. The landing gear position indicator revealed a position consistent with left main gear in the down position and right main gear in the up position. The nose landing gear indication was missing. The panel also contained a JP Instruments EDM 700/EGT-701-9C, which was removed and retained for further examination.

The second instrument panel contained an altimeter which displayed an unreliable indication and a setting of 29.92 inches of mercury, a flap indicator which measured off-scale in the "flaps up" position, an accelerometer which indicated "0" positive and negative g's, a fuel quantity indicator which measured off-scale and unreliable, and a voltmeter which indicated 18 volts. The panel also contained fuel and oil pressure indicators, but their needles were separated from each instrument. The landing gear position indicator revealed a position consistent with left and right main gear in the down position, and the nose landing gear in the up position.

Examination of the engine following recovery revealed four cylinders were separated, but recovered from the debris path. The carburetor was also separated from the engine and 100 low lead fuel was noted leaking from the fitting. The supercharger housing was fractured, and the supercharger impeller showed blade bending, and heavy leading edge grinding; the impeller was also fractured. The accessory housing which was impact separated was inspected and all gears were in position.

Examination of the propeller revealed two blades were intact along their full spans, and one blade was fragmented. One of the intact blades exhibited heavy gouges on the leading edge of the blade, chordwise scratches on the cambered side of the blade and a spanwise gouge on the non-cambered side of the blade. The second intact blade had chordwise scratches on the cambered side of the blade, a smooth radius aft bend, and some chordwise scratches on the cambered side of the blade near the trailing edge. The fragmented blade was fractured into 5 identified pieces. The blade was bent aft about 13 inches from the butt end of the blade. A heavy gouge was noted on the leading edge of the blade, and chordwise scratches were observed on the cambered side of the blade near the blade tip. Heavy spanwise and chordwise scratches were noted on the non-cambered side of the blade.

Postmortem examination of the pilot was performed by the State of West Virginia Office of the Chief Medical Examiner, Charleston, West Virginia. The autopsy report indicated the cause of death was "multiple blunt force injuries due to a plane crash." However, the report continues, "a possibly contributory factor causing pilot incapacitation was evidence of a fresh heart attack."

According to the NTSB Medical Officer Factual Report, a review of the autopsy report indicates the description of the heart itself is limited by the degree of injury. The heart is enlarged and the epicardial surface is adhered to the pericardial sac. A cardiac bypass grafting involves the pericardial surface. Only two vessels are identified secondary to injury (see evidence of Injury). One vessel extends to the mid left anterior descending coronary artery and one vessel extends to the distal left circumflex coronary artery. Both identified graft vessels are patent. Only the native left anterior descending and the left circumflex coronary arteries are able to be identified. The proximal left anterior descending coronary artery has severe atherosclerosis with 85-95% lumen stenosis. The left circumflex coronary artery has moderate atherosclerotic plaque formation. The endocardial surfaces are unremarkable. White scar tissue consistent with remote myocardial infarctions involves the anterior wall and the lateral wall of the left ventricle. An acute myocardial infarction involves the lateral wall of the left ventricle, embedded in the remote myocardial infarction." No microscopic evaluation of the area of the heart in question was performed.

Forensic toxicology was performed on specimens of the pilot by the FAA Bioaeronautical Sciences Research Laboratory, Oklahoma City, Oklahoma, and also by the State of West Virginia Office of the Chief Medical Examiner. The toxicology report for the pilot by FAA stated testing for carbon monoxide and cyanide was not performed. The result for volatiles was positive in the submitted muscle specimen (13 mg/dL), but was negative for ethanol in the submitted liver specimen. A note indicates that the ethanol found in the case is from sources other than ingestion, and putrefaction of the specimens was not noted. Unquantified amounts of Atorvastatin and Metoprolol were detected in the liver, while an unquantified amount of Metoprolol was detected in the submitted kidney specimen.

The toxicology report by the State of West Virginia Office of the Chief Medical Examiner stated testing for alcohol and drugs of abuse was performed on the submitted specimens. The results were positive (0.03 percent wt/wt) for ethanol in the submitted muscle specimen, and no drugs were detected in the liver specimen. A comment section of the report indicated, "Alcohol was present in the muscle at a low concentration. Drugs were not detected in the liver."

The airplane that was flying the opposing pass with the accident pilot (N28XT) was equipped with a camera that recorded and retained video on a micro SD card. The card was submitted to the NTSB Vehicle Recorders Division in an attempt to see if the accident flight was recorded. The lab specialist advised that he was able to see a file tree but did not see anything recorded past September 16, 2011. The card was returned to the owner.

Still digital images, security camera video recordings, and a high definition video recording of the opposing pass were provided to NTSB for review and analysis. The video image recordings were sent to the NTSB Vehicle Recorders laboratory for evaluation. Examination of the high definition video recording revealed it captured both airplanes at about the point where their paths crossed, and continued recording the flight of the accident airplane from that point to ground impact. The video recorded the accident airplane pitching up and rolling left through approximately 270 degrees; however, from about the inverted position, the airplane began a nose-low descent which continued to ground impact.

One individual, who saw a photograph published in a newspaper the day after the crash depicting all six airplanes flying in formation just before the accident called the newspaper 4 days after the picture appeared and reported that to him, it appeared there was an open panel beneath the right wing. On September 23, 2011, which was the day after his call to the newspaper, an article was published in the newspaper with a picture with a circle around the right munitions hard point. On September 24, 2011, the newspaper printed a retraction on the 2nd page, and on September 25, 2011, the newspaper ran an article on the front page describing the mistaken issue related to the open panel.

An NTSB interview of the individual who called the newspaper was performed on September 29, 2011. The individual reported that what he thought was an open panel was actually the right wing munitions hard point.

Further review of the high definition video depicting the accident airplane during the last aerobatic sequence revealed no parts separating from the accident airplane from the moment the accident airplane came into view up to the point of ground impact. All structural components necessary to sustain flight were in view immediately before impact. Additionally, video and still digital images provided to NTSB depicting the bottom of the airplane immediately before the accident did not reveal any open panels, as previously reported by one media outlet, nor any birds.

The NTSB has investigated several accidents and incidents in which pilot incapacitation occurred in-flight. One such investigation involved an accident that occurred on September 6, 1997, at Camden, South Carolina during an intentional aerobatic flight. That investigation and two other investigations spawned Safety Board recommendations A-99-1 and A-99-2 to the FAA. Recommendation A-99-1 specified "Restrict all pilots with special issuance certificates due to cardiac conditions that could affect their G-tolerance from engaging in aerobatic flight", and recommendation A-99-2 to the FAA to, "Restrict all pilots taking medication that reduces G-tolerance from engaging in aerobatic flight."

Additionally, on April 13, 2000, the NTSB Board sent a letter to the FAA referencing 566 additional accidents which had occurred between 1993 and 1999, of which 198 were fatal accidents involving aerobatics or acrobatics. The FAA responded to the Board asking for clarification as to how many of the 198 fatal accidents were related to pilots who had special issuance medical certificates or were taking medication that could reduce their G-tolerance. On March 6, 2001, the Board sent a letter to the FAA correcting the year frame (1983 to 1999), and said upon further review the Board found 231 cases available for release that included the word "aerobatics" or "acrobatics" and asked the FAA to review the 231 cases to determine whether any involved a pilot who had a special issuance medical certificate due to cardiac conditions that could affect his/her G-tolerance, or were taking medication that could reduce his/her G-tolerance. The FAA screened the 231 cases and developed 5 separate criteria during their review. The criteria included:

1.The accident must have occurred during aerobatic flight as defined by FAA Advisory Circulars, regulations. Accidents that occurred during another phase of flight like taxiing, takeoff, cruise, or landing were eliminated.

2.The aerobatic maneuver must have been intentional. Unintentional maneuvers resulting in an accident like inverted stall-spin accidents were eliminated.

3.The aircraft must have been certified for aerobatic flight. Maneuvers conducted in uncertified aircraft were classified as unauthorized maneuvers and not included.

4.The maneuver must have been authorized under FAA regulations. Unless the flight was conducted as part of an air show, recovery from maneuvers must of been completed about 1500 above ground level and parachutes must of been worn (although cases were not eliminated if there was no information available on parachutes). Also, the maneuvers must not have been conducted over congested area, open-air assembly of persons, within airport airspace, within 4 miles of an airway, or when visibility was less than three statute miles. Flights that were conducted in violation of FAA regulations were limited.

5.The airman's cardiac or medication history must have been documented in his/her FAA medical record at the time of the event. Required documentation including appropriate pathology codes, history codes, or EKG codes that indicate cardiac conditions that could affect air G-tolerance and/or the declaration that he/she was taking medication that the potential to reduce G-tolerance. Cases where medical certificates were expired or where appropriate documentation was absent were limited.

Federal Aviation Administration review of the 231 accidents provided by the Safety Board using the above reference criteria revealed only 153 actually involved aerobatics. Further FAA review of the 153 cases using the criteria specified in the NTSB recommendations, and the above listed criteria developed by the FAA, only seven cases met the criteria. Of the seven cases, none matched all five FAA developed criteria. Four of the seven cases involved pilots who did not hold valid medical certificates, and one of the four cases involved an accident where most of the FAA criteria were met; however, the pilot had been denied medical certification; therefore the airman did not hold a valid medical certificate.

The FAA explained in writing to the Safety Board on November 1, 2001, that using the five self-developed criteria, and the Safety Board's original two recommendations, their extensive review of the 231 accidents provided by the NTSB revealed that adoption of the two NTSB safety recommendations would "probably not have changed the outcome and any of the accidents." The letter also specified that, "if the accident data had revealed that there were a significant number of properly identified pilots experiencing aircraft accidents during authorized aerobatic maneuvers, it would have suggested that the adoption of more restrictive practices regarding aerobatic maneuvers would be justified." The FAA Administrator also identified to the NTSB that it expended significant resources for their review, and she believed that the FAA's extensive review had resulted in sufficient supporting data to have these recommendations classified in a "closed reconsidered" status.

A letter from the Chairman of the NTSB to the FAA Administrator dated March 25, 2002, stated that the Board continued to believe that there was a valid cause for concern that pilots with cardiovascular disease may become incapacitated while performing aerobatic maneuvers. The letter also indicated that the two safety recommendations were classified "Closed-Reconsidered."

Using the FAA-developed criteria, analysis of the accident flight revealed all five criteria were met.

During team practice the day before, it was noted that during the opposing pass of the Nos. 5 and 6 airplanes, several FAA inspectors who were at the airport to monitor the airshow noted the accident airplane was low following the aileron roll. The team manager reported that a team debriefing occurred following the practice flight, and the accident pilot reported at that time there were birds in the area which he flew through. He did a knee-jerk maneuver to pull, and as a result he dished out of the maneuver. Because of the issue related to the birds, it was decided to pull or cross at a higher altitude. The team manager also reported that the maneuver being performed at the time of the accident was "eerily similar" in some aspects to the maneuver performed the day before.