N999PPBoeing A75N1(PT17) · 1941

On August 27, 2016, about 1425 Pacific daylight time, a Boeing Stearman A75N1 (PT-17), N999PP, was destroyed when it impacted runway 34 during an aerial demonstration flight at Madras Municipal Airport (S33), Madras, Oregon. The commercial pilot received fatal injuries. The airplane was owned by Unusual Attitudes, LLC and operated by the pilot under the provisions of Title 14 Code of Federal Regulations Part 91. Visual meteorological conditions prevailed, and no flight plan was filed for the exhibition flight.

The pilot was one of several civilian aerial demonstration pilots who performed at the 2-day "Airshow of the Cascades," which included both static and aerial displays. According to information provided by the Federal Aviation Administration (FAA), the public event and aerial demonstrations took place Friday evening and Saturday, August 26-27. The pilot flew the accident airplane in a practice session Friday morning and again during a public demonstration later that evening, about 2000 local; both flights were uneventful, and the pilot completed the maneuver without incident.

The accident occurred during the second day of the event. Witnesses observed the airplane take off from runway 34 and reported that the airplane lifted off the runway and remained in a level attitude just above the runway surface before climbing to perform an inside loop. Witnesses reported that the airplane descended inverted from the top of the loop to a point at which the airplane's pitch attitude was about 10 to 20° nose-down. The airplane continued in that attitude until it impacted terrain adjacent to the runway edge. Witnesses described hearing no abnormalities with the sound of the engine and further stated that it sounded as if the engine was producing power from takeoff until impact. Video footage of the accident showed the pilot performing an inside loop and descending from the top of the loop into terrain.

Another aerial performer at the airshow reported that, before the accident airplane departed, he heard the pilot request over the radio the temperature and density altitude from the Air Boss (the individual responsible for air show operations), who estimated the temperature at 81°F and a density altitude about 4,600 ft. The other performer added that, during the evening practice the day before the accident, he observed the pilot perform the same maneuver. He described the maneuver as "sketchy" because of the low altitude at which the pilot completed the loop. He added that he previously asked the pilot how to perform this maneuver and the pilot stated that it was a "complete crapshoot;" at the top of the loop, the pilot would decide whether he would "pull through and continue the loop or rollout into a half-Cuban or an Immelmann," both of which are recovery aerobatic maneuvers.

The pilot successfully accomplished the inside loop maneuver the previous day, as well as during many previous air shows.

The pilot held a commercial pilot certificate with ratings for single- and multi-engine land, single-engine sea, and instrument airplane. The pilot also held flight instructor ratings for single- and multi-engine airplane and instrument airplane. His most recent FAA second-class medical certificate was issued on June 28, 2016; on that application, the pilot reported 10,000 hours total flight experience with 300 hours in the previous 6 months.

The accident airplane was a single-engine, two-place open-cockpit biplane manufactured by the Boeing Airplane Company in 1941. The airplane was powered by a Pratt & Whitney R-985, air-cooled, 9-cylinder, radial engine equipped with a 2-bladed, variable pitch propeller. The fuselage and empennage comprised a synthetic fabric-covered steel tube structure, while the wings were primarily wood structure covered with the same type of fabric. The airplane was equipped with two tandem open cockpits; the pilot flew the airplane from the aft cockpit.

The airplane's most recent annual inspection was completed on April 20, 2016, at a total aircraft time of 1,271.0 hours.

The 1429 automated weather observation at S33 included wind from 330° at 9 knots, visibility 10 miles, clear skies, temperature 34°C, dew point 2°C, and an altimeter setting of 29.91 inches of mercury.

Given the atmospheric conditions, the calculated density altitude at S33 about the time of the accident was about 5,221 ft.

The pilot successfully completed a similar maneuver Friday evening, the day before the accident flight. The 1956 automated weather observation (timeframe of the flight) was: wind calm, visibility 10 miles, clear skies, temperature 22°C, dew point minus 4°C, and an altimeter setting of 29.89 inches of mercury. Given these atmospheric conditions, the calculated density altitude was about 3,890 ft.

The accident airplane was a single-engine, two-place open-cockpit biplane manufactured by the Boeing Airplane Company in 1941. The airplane was powered by a Pratt & Whitney R-985, air-cooled, 9-cylinder, radial engine equipped with a 2-bladed, variable pitch propeller. The fuselage and empennage comprised a synthetic fabric-covered steel tube structure, while the wings were primarily wood structure covered with the same type of fabric. The airplane was equipped with two tandem open cockpits; the pilot flew the airplane from the aft cockpit.

The airplane's most recent annual inspection was completed on April 20, 2016, at a total aircraft time of 1,271.0 hours.

The wreckage was located adjacent to runway 34 about 3,400 ft from the approach threshold. The first identified point of contact was followed by an approximate 120-ft-long debris path that terminated at the main wreckage. The forward right side of the fuselage, engine cowling and the upper and lower right wings were consumed by post-impact fire.

All major structural components were located and accounted for at the site, and there was no evidence of any pre-impact engine, flight control, or airframe anomalies that would have precluded normal operation.

A complete wreckage examination summary is located in the public docket for this case.

Density Altitude (DA)

The hazards associated with high density altitude are outlined in FAA Pamphlet FAA-P-8740-2, Density Altitude:

Whether due to high altitude, high temperature, or both, reduced air density (reported in terms of density altitude) adversely affects aerodynamic performance and decreases the engine's horsepower output. Takeoff distance, power available (in normally aspirated engines), and climb rate are all adversely affected. Landing distance is affected as well; although the indicated airspeed (IAS) remains the same, the true airspeed (TAS) increases. From the pilot's point of view, therefore, an increase in density altitude results in the following:

• Increased takeoff distance.

• Reduced rate of climb.

• Increased TAS (but same IAS) on approach and landing.

• Increased landing roll distance.

Because high density altitude has particular implications for takeoff/climb performance and landing distance, pilots must be sure to determine the reported density altitude and check the appropriate aircraft performance charts carefully during preflight preparation. A pilot's first reference for aircraft performance information should be the operational data section of the aircraft owner's manual or the Pilot's Operating Handbook developed by the aircraft manufacturer. In the example given in the previous text, the pilot may be operating from an airport at 500 ft MSL, but he or she must calculate performance as if the airport were located at 5,000 ft. A pilot who is complacent or careless in using the charts may find that density altitude effects create an unexpected –and unwelcome – element of suspense during takeoff and climb or during landing.

The Oregon State Medical Examiner's Office, Portland, Oregon, autopsy report indicated that the pilot's cause of death was "multiple blunt force injuries."

The FAA's Bioaeronautical Sciences Research Laboratory, Oklahoma City, Oklahoma, conducted forensic toxicology examinations on specimens from the pilot; no carbon monoxide, ethanol, or any screened drugs of abuse were detected.