# NTSB MIA94LA103: Cessna 172RG, N9781B, Boca Raton, FL, March 26, 1994 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: March 26, 1994, 12:15 local (17:15 UTC) - Place: Boca Raton, FL - Coordinates: 26.36943, -80.099235 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=26.3694&lon=-80.0992&mi=10 - Phase of flight: [Initial climb](https://openairdocs.org/ntsb-phases/350) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 2 uninjured - Status: Completed, report November 18, 1994 - Report: Approved by Office Director - NTSB case key (mKey): 37513 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=MIA94LA103 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/37513/pdf - Page: https://openairdocs.org/ntsb/MIA94LA103 ## Probable cause The failure of the aircraft operator to comply with engine manufacturers service bulletins which resulted in improper inspection of exhaust valves and subsequent sticking of the no. 4 exhaust valve. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Loss of engine power(partial) - mech failure/malf, takeoff - initial climb - maintenance,service bulletin/letter - not performed, company maintenance personnel (cause) - engine assembly,valve,exhaust - seized (cause) - engine assembly,push rod - bent (cause) - Forced landing, descent - emergency - On ground/water collision with object, landing - flare/touchdown - object - tree(s) ## Analysis The aircraft's engine lost partial power during climb after takeoff. The aircraft would not maintain altitude and a forced landing was made in a wooded area. Postcrash examination of the engine indicated the No. 4 exhaust valve had stuck and the exhaust valve pushrod was bent. No other engine malfunctions were noted. Textron Lycoming Engines issued mandatory service bulletin 388B on May 13, 1992, requiring the testing of the exhaust valve clearances each 400 flight hours on aircraft. The logbook records for N9781B did not have any entries showing compliance with service bulletin 388B. ## Factual narrative On March 26, 1994, about 1215 eastern standard time, a Cesnna 172RG, N9781B, registered to ATE of Florida, Inc., landed in a wooded area following partial loss of engine power shortly after takeoff from Boca Raton Airport, Boca Raton, Florida, while on a 14 CFR Part 91 instructional flight. Visual meteorological conditions prevailed at the time and no flight plan was filed. The aircraft received substantial damage and the commercial-rated flight instructor and private-rated dual student were not injured. The flight originated at Fort Lauderdale, Florida, on March 26, 1994, about 1120. The flight instructor stated that the aircraft's engine lost partial power during climb after takeoff. They were unable to maintain altitude and a forced landing was made in a wooded area. After the accident maintenance personnel from the operator and a FAA inspector found the exhaust valve in the No. 4 cylinder had stuck and the push rod was bent. No other malfunctions in the engine were noted. Textron Lycoming Engines issued mandatory service bulletin 388B on May 13, 1992. This bulletin outlined a "procedure to determine exhaust valve and guide condition" and is "to insure positive and trouble free valve train operation." This bulletin required compliance each 400 hours of engine operation. Logbook records indicated the engine had accumulated 1,030 hours of operation since major overhaul and no entries to indicate service bulletin 388B had been complied with. ## Aircraft - Registration: [N9781B](https://openairdocs.org/deregistered/N9781B-1996-08-27), registration cancelled 1996-08-27, S/N 172RG1032 (OpenAirDocs) - Reported make and model: CESSNA 172RG - Registry model: [Cessna 172RG](https://openairdocs.org/model/cessna-172rg) (registry code 2072438) (OpenAirDocs) - Category: Airplane - Serial number: 172RG1032 - Airframe hours: 5290 - Engines: LYCOMING O-360-FIA6 180 horsepower reciprocating - Damage: Substantial damage - Flight: Instructional, Part 91 - Registered owner: Ate Of Florida, Inc. - Airworthiness certificate: Standard, Normal - Last inspection: AAIP, March 21, 1994, 9 hours before - Airport: BCT, Boca Raton ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 23; flight instructor, commercial; airplane ratings: single-engine land; instrument ratings: airplane; medical: class 2, valid medical--no waivers/lim.; seat: right; flight hours: 645 total, 132 in this make and model, 570 as pilot in command, 202 in the last 90 days, 54 in the last 30 days, 2 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 90° at 10 knots - Visibility: 7 statute miles - Lowest ceiling: none - Temperature: 84 °F, dew point 70 °F - Altimeter: 30.00 inHg - Observed at: FXE, 10 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 19940326006719A](https://openairdocs.org/incident/19940326006719A), Mar 26, 1994: Cessna 172RG, Baco Raton, FL, Substantial damage. Lost partial power on climbout. Force landed in trees. Stuck valve. Service bulletin not complied on valve train. 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.