FREEHOLD TWSP, NJ, USA
N917JD
Pitts S-2B
After being airborne on a local flight for what the pilot estimated as 20 minutes, the engine lost power. Witnesses observed the airplane in a forced landing, about 20 feet above the ground, when the nose suddenly dropped and the airplane struck the ground in a nose low attitude. Less than a quart of fuel was found in the fuel tanks and fuel sump. No fuel was found in the fuel lines, and there was no evidence of a fuel spill. The airplane had two fuel quantity measuring systems. One was electronic and recorded fuel used. The other measured quantity, and consisted of a sight gage. The pilot reported that the fuel tank was 60 to 70 percent full (13.8 to 16.1 gallons) on preflight. The sight gage indicates more fuel on the ground than in flight. According to the flight manual, the sight gage is calibrated for level flight only. A production test pilot reported that the airplane's nose will drop straight ahead in a coordinated stall.
HISTORY OF FLIGHT On April 6, 1996, about 1610 eastern standard time, a Pitts S-2B, N917JD, was destroyed during a forced landing in Freehold Township, New Jersey. The commercial pilot received serious injuries, and the passenger was fatally injured. Visual meteorological conditions prevailed, and no flight plan had been filed for the local flight which departed Old Bridge, New Jersey, earlier, at an undetermined time, and was operated under 14 CFR Part 91. A witness observed the pilot preparing the airplane for departure about 1415. No witnesses were located who observed the departure. Witnesses observed the accident airplane in the Freehold Township area about 1600. One witness saw the airplane in a climb and heard the engine. He reported it sounded normal, until the engine sputtered and stopped. The airplane then pitched down, and he lost sight of the airplane behind buildings. Other witness saw the airplane in the final stages of the forced landing, and reported that as the airplane neared the ground, in a wings level attitude, the nose dropped, and it impacted the ground nose first. Witnesses and emergency personnel who responded to the scene did not report a smell of fuel. In the NTSB Accident Report, the pilot stated: "We departed Old Bridge Airport for a short VFR pleasure flight in the local area. We flew south/southeast of the airport at about 2,000-3,000' [feet]. No acrobatic maneuvers were performed. While in a cruise descent back to Old Bridge, at an altitude of about 1,000' [feet] AGL, the engine suddenly ceased operating. I remember setting the aircraft up for an off-airport emergency landing. I have no memory of the last moments of the flight prior to the crash. I do not precisely recall the exact time of the afternoon departure from Old Bridge, but the entire flight lasted about twenty minutes." The accident occurred during the hours of daylight at location 40 degrees, 14 minutes, 6 seconds North and 74 degrees, 14, minutes, 51 seconds, West. PERSONNEL INFORMATION The rear seat pilot was the holder of Commercial Pilot Certificate, with airplane single engine land/sea, multi-engine land, and instrument airplane ratings. He also held a flight instructor certificate for airplane single and multi-engine land, and instrument airplane. He was issued an FAA 2nd Class Airman Medical Certificate on April 6, 1995. According to the pilot's log book, this was his first flight in a tail wheel airplane and the Pitts S-2B since November 27, 1995. However, the pilot had flown 8.3 hours in the preceding 90 days. The front seat pilot held an expired student pilot certificate. According to FAA records, she had in excess of 57 hours. AIRCRAFT INFORMATION The airplane was a 1994 Pitts S-2B, built by Aviat, Inc., in Afton, Wyoming. It was powered by a Lycoming AEIO-540-D4A5 engine which developed 260 horse power. The airplane had two fuel tanks. The main tank located behind the firewall, and forward of the front seat held 23 gallons useable, and the auxiliary tank located in the upper wing held 5 gallons useable. The airplane was equipped with a sight gage on the rear instrument panel for determining fuel quantity. This gage consisted of a clear plastic tube which was connected to the main fuel tank. The fluid observed in the tube was at the same level as in the fuel tank. According to Aviat, the system was calibrated for level flight, and not ground. The FAA approved airplane flight manual stated: "...The empty line is at the useable fuel level in tank in level flight. It is very important to know what amount of fuel you have on board before any flight is attempted...." In addition to the sight gage, the airplane was equipped with an electronic fuel used counter. In a telephone interview, a production test pilot for Aviat, reported that in a coordinated stall, the nose of the airplane drops straight ahead, and there is no tendency to fall off on a wing. The buffet will appear about three to five miles per hour prior to the stall, and the stall speed would be about 65 mph. WRECKAGE AND IMPACT INFORMATION The airplane was examined at the accident site on April 7, 1996. The airplane had impacted in an open field. To extricate one of the occupants, the wings were removed, and the fuselage rolled from its impact position. Both blades of the propeller were bent rearward. There was no leading edge impact damage or chordwise scratching on the front surface. The engine was still attached by the mounts, and been pushed up about 60 degrees. Compression was found in all cylinders, and valve train continuity was confirmed. The sparkplugs were gray in appearance. The fuel system was intact with all lines attached. No fuel was found in any fuel lines. However, about 20 ounces of fuel was drained from the fuel tank and fuel strainer. The fuel caps for both tanks were found at the accident site. A hole about the size of a nickel was found on the upper left side of the main fuel tank. The metal around the hole was bent inward. There was no evidence of a fuel spill, leak, or siphoning from the fuel tanks. In addition, there was no evidence of a ground fuel spill. The instrument panel on the front cockpit was pushed toward the rear. The rear cockpit maintained its shape. Flight control continuity was verified between both cockpits and the empennage. Flight control continuity to the ailerons was compromised when the wings were removed. Aileron push rods were found separated in the same areas that the wings were separated from the fuselage. MEDICAL AND PATHOLOGICAL INFORMATION An autopsy was conducted on the passenger by Sogra Saleem, M.D., medical examiner for Monmouth County, New Jersey, on April 8, 1996. Toxicological testing was conducted by the FAA Civil Aeromedical Institute, Oklahoma City, Oklahoma. The results were negative for drugs and alcohol. TESTS AND RESEARCH The electronic fuel quantity used system was removed for additional testing. Upon power up, the unit registered 0.2 gallons used. No other fuel used data was available from the unit. The fuel flow transmitter was functionally checked and found to be within limits. ADDITIONAL INFORMATION The last known refueling took place at the Old Bridge Airport on November 26, 1995, when the airplane was serviced 13.6 gallons of 100LL. According to the pilot's log book, the airplane was flown again on November 27, 1995, for 1.2 hours. In addition, the pilot was observed to periodically start up the engine during the winter months. There were no records of a refueling after these events. Fuel burn is a function of the engine power setting, altitude flown, and amount of leaning applied to the mixture. The cruise charts from the FAA approved flight manual for the Pitts S-2B revealed a fuel burn of 11 gallons per hour at 10,000 feet, at 2,200 RPM, and 19 inches of manifold pressure. This increased to 21.2 gallons per hour at 2,000 feet, at 2,700 RPM, and 27 inches of manifold pressure. The pilot reported that during pre-flight, the sight gage indicated a fuel load of 60 to 70 percent full (13.8 gallons to 16.1 gallons). In addition, the fuel tank located in the upper wing was empty. According to the FAA Approved flight manual for the airplane, "...The sight gage will only show fuel levels in level flight...." The pilot also reported that he was aware that the sight gage would indicate more fuel than was actually present when the airplane was in a three point attitude on the ground. The aircraft wreckage was released to Freehold Township Police Department on April 8, 1996.
the pilot's improper fuel management which resulted in a power loss due to fuel exhaustion, and his failure to maintain airspeed during a forced landing which resulted in an inadvertent stall.
Source: NTSB Aviation Accident Database
Aviation Accidents App
In-Depth Access to Aviation Accident Reports
