# NTSB LAX04LA022: American AA-1, N5968L, San Martin, CA, October 22, 2003 - Type: NTSB accident investigation - Classification: Accident · Serious injuries · Limited investigation · Final report - Date: October 22, 2003, 15:15 local (22:15 UTC) - Place: San Martin, CA - Coordinates: 37.681667, -121.596946 - Nearby events: https://openairdocs.org/map.md?lat=37.6817&lon=-121.5969&mi=10 - Phase of flight: [Initial climb](https://openairdocs.org/ntsb-phases/350) (OpenAirDocs' grouping) - Highest injury: Serious injuries - Injuries: 2 serious - Status: Completed, report December 28, 2004 - Report: Approved by Office Director - Parties: Federal Aviation Administration - NTSB case key (mKey): 58241 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=LAX04LA022 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/58241/pdf - Page: https://openairdocs.org/ntsb/LAX04LA022 ## Probable cause The absence of compression in two of the airplane's four cylinders, and the pilot/mechanic's failure to maintain the engine in an airworthy condition, which resulted in a loss of engine power during takeoff-initial climb, and subsequent forced landing. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Loss of engine power, takeoff - initial climb - engine assembly,cylinder - low compression (cause) - maintenance,service of aircraft/equipment - not performed, owner/pilot mechanic (cause) - Forced landing, emergency landing after takeoff - On ground/water collision with object, landing - roll - terrain condition - rough/uneven - object - fence ## Analysis The student pilot/airplane owner, who is also an aviation mechanic, reported a loss of engine power after takeoff during the initial climb. He said the engine was running rough, and started to lose power. He was unable to maintain altitude, and made a forced landing. The airplane collided with a fence during the landing roll. An examination of the engine disclosed virtually no compression in two of the four cylinders, an absence of an air cleaner, excessively wide gaps on all of bottom spark plugs, and a heavily sooted and fouled number 4 top spark plug. The engine was installed in July, 1978, and had accumulated 2157.5 total operating hours; it has never been overhauled. ## Factual narrative HISTORY OF FLIGHT On October 22, 2003, at 1515 Pacific daylight time, an American AA-1, N5968L, collided with the ground during a forced landing at South County Airport, San Martin, California. The forced landing was precipitated by a loss of engine power during the initial takeoff climb. The student pilot/owner was operating the airplane under the provisions of 14 CFR Part 91. The pilot and passenger were seriously injured, and the airplane was substantially damaged. Visual meteorological conditions prevailed, and a flight plan had not been filed. The pilot stated in the Pilot/Operator Accident Report, that at 300 feet (agl) the engine became rough, lost power, and he could not maintain altitude. The pilot directed the airplane to an open area that was a county vehicle depot, and struck the depot boundary fence after making the landing. Damage to the airplane included the collapse or shearing off of the tricycle landing gear and leading edge damage to both wings. An aircraft airframe and power-plant mechanic examined the airplane under the supervision of an FAA Inspector. The mechanic reported that the carburetor air filter was not present, the number 4 top spark plug was leaded and sooty, all gaps on the bottom spark plugs were wide, the number 2 and 4 cylinders had measured compression ratios of 5/80 and 0/80 psi respectively, and the piston wrist pins had been scraping on the cylinder walls of the number 2 and 4 cylinders. The pilot, who was also the airplane's mechanic, reported that the Lycoming O-235-C2C engine had been installed on July 27, 1978, with at total time of 1510.57 hours and that the engine had not been overhauled since installation. The pilot provided copies of pages from the engine logbook that showed the last annual inspection on the engine was done on March 1, 2003, at a total time of 2157.5 hours. The airframe maintenance log book records a aircraft total time of 3343.4 hours on March 1, 2003, during its last airframe annual inspection. PERSONAL INFORMATION A review of FAA airman records revealed that the pilot held a student pilot certificate issued on June 10, 2003. He was issued a third class medical certificate on June 10, 2003, with the restriction that he posses glasses for near and intermediate vision. ADDITONAL INFORMATION Manufacturers Recommended Time Between Overhaul Periods (TBO) Lycoming Service Instruction 1009AQ, affecting all Lycoming piston aircraft engines, states that "all engines that do not accumulate the hourly period of time between overhauls specified in this publication are recommended to be overhauled in the twelfth year". The specified time between overhauls (TBO) for the O-235-C2C engine is 2,400 hours. ## Aircraft - Registration: [N5968L](https://openairdocs.org/deregistered/N5968L-2005-09-23), registration cancelled 2005-09-23, S/N AA1-0268, built 1969 (OpenAirDocs) - Reported make and model: American AA-1 - Registry model: [American AA-1](https://openairdocs.org/model/american-aa-1) (registry code 0630610) (OpenAirDocs) - Registry engine: [Lycoming 0-235 series](https://openairdocs.org/engine/lycoming-0-235-series) (registry code 41505, 4 cycle) (OpenAirDocs) - Category: Airplane - Serial number: 268 - Airframe hours: 3343.4 - Engines: Lycoming O-235-C2C 115 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Operator: Michael D. White - Registered owner: Kevin David Carey - Airworthiness certificate: Standard, Normal - Last inspection: 100 hour, March 1, 2003 - Departed: KQ99, San Martin, CA - Destination: KWLW, Willows, CA - Airport: KQ99, South County Airport ## Flight crew As NTSB recorded them. NTSB leaves out names. - Student pilot; age 47; injuries: serious; student; medical: class 3, valid medical--w/ waivers/lim; last flight review September 15, 2003; seat: left; flight hours: 121 total, 112 in this make and model, 7 in the last 90 days, 2 in the last 30 days ## Weather - Conditions: Visual (VMC), Day - Wind: 300° at 14 knots - Visibility: 15 statute miles - Lowest ceiling: 20,000 ft broken - Temperature: 72 °F, dew point 55 °F - Altimeter: 30.10 inHg - Observed at: KRHV, 28 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 20031022029239A](https://openairdocs.org/incident/20031022029239A), Oct 22, 2003: Amrgen AA1, San Martin, CA, Substantial damage. (-23) Aircraft lost power between 100 and 300 feet on takeoff and forced to land off airport. Pilot indicated that getting the aircraft on the ground in the… 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.