# NTSB FTW01LA120: Kirchner Pietenpol Aircamper, N25157, Tulsa, OK, May 17, 2001 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: May 16, 2001, 19:39 local (May 17, 2001, 00:39 UTC) - Place: Tulsa, OK - Coordinates: 36.049633, -96.019371 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=36.0496&lon=-96.0194&mi=10 - Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report February 5, 2002 - Report: Approved by Office Director - Parties: OKC FSDO - NTSB case key (mKey): 52282 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=FTW01LA120 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/52282/pdf - Page: https://openairdocs.org/ntsb/FTW01LA120 ## Probable cause the pilot's inadequate flare during the forced landing, which resulted in a hard landing. A contributing factor was the engine overheating due a stuck oil cooler thermostat valve, which resulted in a loss of power. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Loss of engine power, cruise - lubricating system,oil cooler (contributing factor) - fluid,oil - obstructed (contributing factor) - oil cooler control - jammed (contributing factor) - Forced landing, descent - emergency - Hard landing, landing - flare/touchdown - flare - inadequate, pilot in command (cause) ## Analysis During cruise flight in the homebuilt airplane, the pilot observed a rise in engine oil temperature. He elected to make a precautionary landing at a nearby airport; however, engine rpm decreased to where altitude could not be maintained. The pilot initiated a forced landing to a bean field about one mile northeast of the airport. During the landing, the airplane touched down hard, nosed over, and came to rest inverted. An examination of the Corvair automotive engine, by the owner, revealed a stuck oil cooler thermostat valve. The stuck valve was preventing oil from flowing through the oil cooler. ## Factual narrative On May 16, 2001, at 1939 central daylight time, a Kirchner Pietenpol Aircamper home built airplane, N25157, was substantially damaged during a forced landing following a loss of engine power near Tulsa, Oklahoma. The airplane was owned and operated by the pilot. The private pilot, sole occupant, was not injured. Visual meteorological conditions prevailed, and a flight plan was not filed for the 14 Code of Federal Regulations Part 91 personal flight. The flight originated from the Sand Ridge Airport near Collinsville, Oklahoma, at 1910, and was destined for the Richard Lloyd Jones Jr. Airport, Tulsa, Oklahoma. While en route, the pilot observed a rise in engine oil temperature. The pilot elected to make a precautionary landing at the Harvey Young Airport; however, engine rpm decreased to where altitude could not be maintained. The pilot initiated a forced landing to a bean field about one mile northeast of the airport. During the landing, the airplane touched down "hard," nosed over, and came to rest inverted. Examination of the airplane by FAA inspectors, who responded to the accident site, revealed that the main landing gear had collapsed and was partially separated. The right wing spar outboard of the lift strut was fractured, and the vertical stabilizer was damaged. An examination of the Corvair automotive engine, by the owner, revealed a stuck oil cooler thermostat valve. The thermostat valve was found stuck in the position that would prevent oil from flowing through the oil cooler. Additionally, pieces of a broken piston ring were found in the engine's oil sump. Attempts to obtain a completed Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1/2, from the pilot/owner were unsuccessful. ## Aircraft - Registration: [N25157](https://openairdocs.org/deregistered/N25157-2013-08-06), registration cancelled 2013-08-06, S/N 113EHK, built 1978 (OpenAirDocs) - Reported make and model: Kirchner Pietenpol Aircamper - Registry model: [Kirchner PIETENPOL AIRCAMPER](https://openairdocs.org/model/kirchner-pietenpol-aircamper) (registry code 7040319) (OpenAirDocs) - Registry engine: [Amateur-built UNKNOWN ENG](https://openairdocs.org/engine/amateur-built-unknown-eng) (registry code 99999) (OpenAirDocs) - Category: Airplane, amateur-built - Serial number: 113EHK - Engines: Corvair reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Registered owner: Earl D. Pittinger Jr. - Airworthiness certificate: Special, Experimental (Special) - Departed: OK94, COLLINSVILLE, OK - Destination: RVS, Tulsa, OK ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 54; injuries: none; private; airplane ratings: single-engine land; medical: class 3, valid medical--w/ waivers/lim; seat: rear; flight hours: 1,000 total ## Weather - Conditions: Visual (VMC), Day - Wind: 190° at 14 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 82 °F, dew point 72 °F - Altimeter: 29.68 inHg - Observed at: TUL, 5 nm away ## FAA reports on this event (1) The FAA's own accident and incident reports, matched to the aircraft by N-number and date (OpenAirDocs). - [Accident 20010516009149A](https://openairdocs.org/incident/20010516009149A), May 16, 2001: Amtr PIETENPOLAIR, Tulsa, OK, Substantial damage. (.19)On may 16, 2001, at 1939 central daylight time, a kirchner pietenpol aircamper home built airplane, N25157, was substantially damaged during a forced… ## Other investigations on N25157 (1) From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model. - [NTSB MKC79DER74](https://openairdocs.org/ntsb/MKC79DER74), Sep 21, 1979: Pietenpol Aircmp (N25157), Minneapolis, MN, substantial damage From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model. --- OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.