Saturday, October 13, 2018

Pitts Model 12, N12DR: Accident occurred April 18, 2015 near Falconhead Airport (37K), Burneyville, Love County, Oklahoma

The National Transportation Safety Board did not travel to the scene of this accident.

Additional Participating Entity:
Federal Aviation Administration / Flight Standards District Office; Oklahoma City, Oklahoma

Aviation Accident Factual Report - National Transportation Safety Board: https://app.ntsb.gov/pdf

Investigation Docket - National Transportation Safety Board: https://dms.ntsb.gov/pubdms

http://registry.faa.gov/N12DR

Location: Burneyville, OK
Accident Number: CEN15LA205
Date & Time: 04/18/2015, 1748 CDT
Registration: N12DR
Aircraft: PITTS Model 12
Aircraft Damage: Substantial
Defining Event: Fuel contamination
Injuries: 1 Minor
Flight Conducted Under: Part 91: General Aviation - Personal 

On April 18, 2015, about 1748 central daylight time, an experimental, amateur-built Pitts model 12 airplane, N12DR, was substantially damaged during a forced landing near Falconhead Airport (37K), Burneyville, Oklahoma. The commercial pilot sustained minor injuries. The airplane was registered to and operated by the pilot under the provisions of Title 14 Code of Federal Regulations (CFR) Part 91 as a personal flight. Day visual meteorological conditions prevailed, and no flight plan was filed for the local flight that departed about 1740.

The pilot reported that after a short local flight he reentered the traffic pattern on the downwind leg to practice landings on runway 18 at 37K. The pilot stated that after entering the downwind leg he made an initial reduction of engine power to 22 inches-of-manifold pressure and 2,000 rpm and that the airplane decelerated to 100 mph. He subsequently made another engine power reduction to about 15 inches-of-manifold pressure at 2,000 rpm when the airplane was abeam the approach end of runway 18. During the base leg he determined that the airplane would require additional engine power to land at his preferred touchdown point on the runway; however, the engine did not respond when he advanced the throttle. He subsequently increased both the throttle and propeller controls with no noticeable change in engine power. The pilot reported that the airplane did not have enough altitude to reach the runway, so he made a left 90° turn from the final approach toward an open wheat field for a forced landing. He stated that the airplane came to rest nose down after both main landing gear collapsed upon landing in soft muddy terrain. The forward fuselage, engine mounts, and both lower wings were substantially damaged during the accident.

A postaccident examination established that the main fuel tank was leaking from a broken fuel line, but the tank still contained ample fuel (about 3/4 full). Throttle and mixture control cable continuity was confirmed from the cockpit to their respective engine components; however, the controls did not move due to impact-related damage. Flight control cable continuity was established from each flight control surface to its respective cockpit control. Both main landing gear had collapsed aft during impact. The engine remained partially attached to the firewall through several damaged mounts. Internal engine and valve train continuity were confirmed as the crankshaft was rotated. Except for cylinder no. 5, compression and suction were noted on all cylinders in conjunction with crankshaft rotation. A borescope inspection of the no. 5 cylinder did not reveal any anomalies and confirmed piston and valves movement in conjunction with crankshaft rotation. The lack of compression on cylinder no. 5 was attributed to a stuck ring and not to a mechanical failure. The forward spark plugs were removed and exhibited features consistent with normal engine operation. A functional test of the fuel selector revealed no anomalies. There was no evidence of a vent restriction to the main tank when compressed air was blown into the fuel system vent line. There were no restrictions noted with the vapor return line between the main tank and the bubbler, and the correct restricted orifice was installed in the line. The fuel system exhibited impact-related damage of several fuel lines and their associated fittings. The main fuel line contained an unmeasured amount of water and there was a white paste-like material inside the line fitting. The fuel drain for the header tank separated during impact, and about 1 teaspoon of water was recovered from the header tank. About 3 tablespoons of uncontaminated fuel was recovered from the throttle body inlet and about 6 fluid ounces of uncontaminated fuel was drained from the bubbler assembly. The fuel system did not have a gascolator installed; however, the airplane was equipped with a 62 micron inline fuel filter. A visual inspection of the fuel filter revealed trace amounts of aluminum shavings, water, cellophane tape, and organic material. There was white Teflon paste observed on the inlet threads to the electric fuel pump. No anomalies were noted with the electric fuel pump during a functional test. The mechanical fuel pump was removed and provided fuel flow during a bench test. There was mud found impacted in the fuel controller assembly that was attributed to impact. The fuel controller reference line fitting was found finger tight. Examination of the fuel injection nozzle did not reveal any evidence of water contamination on the interior nozzle passages; however, the fuel disk revealed trace mud deposits that were attributed to impact. 

Pilot Information

Certificate: Commercial
Age: 67, Male
Airplane Rating(s): Multi-engine Land; Single-engine Land
Seat Occupied: Rear
Other Aircraft Rating(s): None
Restraint Used: 5-point
Instrument Rating(s): Airplane
Second Pilot Present: No
Instructor Rating(s): None
Toxicology Performed: No
Medical Certification: Class 2 With Waivers/Limitations
Last FAA Medical Exam: 05/01/2014
Occupational Pilot: No
Last Flight Review or Equivalent: 11/08/2013
Flight Time:  (Estimated) 5451 hours (Total, all aircraft), 12 hours (Total, this make and model), 5253 hours (Pilot In Command, all aircraft), 29 hours (Last 90 days, all aircraft), 12 hours (Last 30 days, all aircraft), 0 hours (Last 24 hours, all aircraft)

Aircraft and Owner/Operator Information

Aircraft Make: PITTS
Registration: N12DR
Model/Series: Model 12
Aircraft Category: Airplane
Year of Manufacture: 2013
Amateur Built: Yes
Airworthiness Certificate: Experimental
Serial Number: 281
Landing Gear Type: Tailwheel
Seats: 2
Date/Type of Last Inspection: 03/06/2015, Condition
Certified Max Gross Wt.: 2250 lbs
Time Since Last Inspection:
Engines: 1 Reciprocating
Airframe Total Time: 107 Hours at time of accident
Engine Manufacturer: Vedeneyev
ELT: C91A installed, not activated
Engine Model/Series: M14P
Registered Owner: On file
Rated Power: 400 hp
Operator: On file
Operating Certificate(s) Held: None

Meteorological Information and Flight Plan

Conditions at Accident Site: Visual Conditions
Condition of Light: Day
Observation Facility, Elevation: 1F0, 845 ft msl
Distance from Accident Site: 16 Nautical Miles
Observation Time: 1755 CDT
Direction from Accident Site: 33°
Lowest Cloud Condition: Scattered / 5000 ft agl
Visibility:  10 Miles
Lowest Ceiling: None
Visibility (RVR):
Wind Speed/Gusts: 4 knots /
Turbulence Type Forecast/Actual: None / None
Wind Direction: 160°
Turbulence Severity Forecast/Actual: N/A / N/A
Altimeter Setting: 29.77 inches Hg
Temperature/Dew Point: 23°C / 13°C
Precipitation and Obscuration: No Obscuration; No Precipitation
Departure Point: Burneyville, OK (37K)
Type of Flight Plan Filed: None
Destination: Burneyville, OK (37K)
Type of Clearance: None
Departure Time: 1740 CDT
Type of Airspace: Class G

Airport Information

Airport: Falconhead Airport (37K)
Runway Surface Type: Asphalt
Airport Elevation: 690 ft
Runway Surface Condition: Dry
Runway Used: 18
IFR Approach: None
Runway Length/Width: 4400 ft / 75 ft
VFR Approach/Landing:  Forced Landing; Traffic Pattern 

Wreckage and Impact Information

Crew Injuries: 1 Minor
Aircraft Damage: Substantial
Passenger Injuries: N/A
Aircraft Fire: None
Ground Injuries: N/A
Aircraft Explosion: None
Total Injuries: 1 Minor
Latitude, Longitude:  33.925833, -97.296389 (est)

NTSB Identification: CEN15LA205 
14 CFR Part 91: General Aviation
Accident occurred Saturday, April 18, 2015 in Burneyville, OK
Aircraft: DOUGLAS RIPLEY PITTS MODEL 12, registration: N12DR
Injuries: 1 Minor.

This is preliminary information, subject to change, and may contain errors. Any errors in this report will be corrected when the final report has been completed. NTSB investigators may not have traveled in support of this investigation and used data provided by various sources to prepare this aircraft accident report.

On April 18, 2015, about 1810 central daylight time, an experimental amateur-built Ripley Pitts model 12 airplane, N12DR, was substantially damaged during a forced landing near Falconhead Airport (37K), Burneyville, Oklahoma. The commercial pilot sustained minor injuries. The airplane was registered to and operated by the pilot under the provisions of 14 Code of Federal Regulations Part 91 without a flight plan. Day visual meteorological conditions prevailed for the local flight that departed about 1800.

The pilot reported that after a short local area flight he reentered the traffic pattern to practice landings on runway 18 (4,400 feet by 75 feet, asphalt). He stated that while on the downwind leg he reduced engine power to initiate a descent to the runway. During the base leg he determined that the airplane would need additional engine power to land at his preferred touchdown point on the runway; however, the engine did not respond as he advanced the throttle. He then fully advanced both the throttle and propeller controls with no noticeable increase in engine power. Believing that the airplane did not have enough altitude to safely glide to the runway, the pilot made a turn toward a nearby open grass field for a forced landing. He stated that the airplane's main landing gear collapsed after encountering soft turf during the landing. The forward fuselage, firewall, engine mount, and both lower wings were substantially damaged during the impact sequence.

No comments: