# NTSB CEN22LA413: Piper PA32RT, N31981, Bulverde, TX, September 9, 2022 - Type: NTSB accident investigation - Classification: Accident · No injuries · Class 3 · Limited · Final report - Date: September 9, 2022, 07:50 local (12:50 UTC) - Place: Bulverde, TX - Coordinates: 29.75067, -98.453328 - Nearby events: https://openairdocs.org/map.md?lat=29.7507&lon=-98.4533&mi=10 - Phase of flight: [Initial climb](https://openairdocs.org/ntsb-phases/350) (OpenAirDocs' grouping) - Defining event: [Initial climb: Loss of engine power (partial)](https://openairdocs.org/ntsb-events/342) - Highest injury: No injuries - Injuries: 2 uninjured - Status: Completed - Report: Approved by Office Director - Investigation class: Class 3 - NTSB office: Central Region - Parties: FAA FSDO, Lycoming - NTSB case key (mKey): 105901 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CEN22LA413 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/105901/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=105901 - Page: https://openairdocs.org/ntsb/CEN22LA413 ## Probable cause The partial loss of engine power due to excessive carbon deposits that resulted in one or more stuck exhaust valves. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Engine (reciprocating): recip eng cyl section](https://openairdocs.org/ntsb-findings/01058530): Aircraft › Aircraft power plant · Malfunction (probable cause); cases with it: [Piper PA-32RT-300T, 1 case](https://openairdocs.org/ntsb-findings/01058530/cases.md?model=7103216), [All aircraft, 373 cases](https://openairdocs.org/ntsb-findings/01058530/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Initial climb: Loss of engine power (partial)](https://openairdocs.org/ntsb-events/342) (defining event); cases with it: [Piper PA-32RT-300T, 5 cases](https://openairdocs.org/ntsb-events/342/sequence.md?model=7103216), [All aircraft, 1,858 cases](https://openairdocs.org/ntsb-events/342/sequence.md) ## Analysis The pilot reported the airplane did not accelerate as usual during the takeoff roll. To avoid obstacles at the end of the runway, the pilot continued the takeoff. The airplane cleared powerlines, trees, and a school, but was nearing a stall so the pilot decided to make a forced landing in a field. During the landing the airplane collided with a tree, resulting in substantial damage to the right wing and fuselage. Examination of the engine found excessive carbon deposits around the No. 4 cylinder exhaust valve. A large amount of carbon buildup was found on the rocker arm, rocker shaft, and valve spring. The rotator cap also had carbon deposits and exhibited a groove wear pattern consistent with a lack of cap rotation. The exhaust valve guide had excessive wobble and movement within the guide. The No. 5 exhaust valve also displayed signatures of carbon buildup but not to the same extent as the No. 4. No other anomalies were detected with the engine or airframe. The loss of engine power was likely due to at least one stuck exhaust valve. ## Factual narrative On September 9, 2022, about 0750 central daylight time, a Piper PA32RT-300T airplane, N31981, was substantially damaged when it was involved in an accident near Bulverde, Texas. The pilot and passenger were not injured. The airplane was operated under the provisions of Title 14 Code of Federal Regulations Part 91 as a personal flight. The pilot reported that during the takeoff from Bulverde Airpark (1TT8), Bulverde, Texas, the airplane did not accelerate as planned. The pilot reported that he was not going to be able to stop on the remaining runway, so he continued the takeoff in order to avoid contacting a fence and vehicles at the end of the runway. The airplane cleared powerlines, trees, and a school at the end of the runway, but was nearing a stall, so the pilot performed a forced landing to a field. During the landing the airplane collided with a tree, resulting in substantial damage to the right wing and fuselage. Postaccident examination of the engine found excessive carbon deposits around the No. 4 cylinder exhaust valve. A large amount of carbon build up was found on the rocker arm, rocker shaft, and valve spring. The rotator cap also had carbon deposits and exhibited a groove wear pattern consistent with a lack of cap rotation. The exhaust valve guide had excessive wobble and movement within the guide. The No. 5 exhaust valve also displayed signatures of carbon buildup but not to the same extent as the No. 4. No other anomalies were detected with the engine or airframe. ## Aircraft - Registration: [N31981](https://openairdocs.org/aircraft/N31981), registered now, S/N 32R-7887018, built 1978 (OpenAirDocs) - Reported make and model: PIPER PA32RT (300T) - Registry model: [Piper PA-32RT-300T](https://openairdocs.org/model/piper-pa-32rt-300t) (registry code 7103216) (OpenAirDocs) - Registry engine: [Lycoming TI0-540 series](https://openairdocs.org/engine/lycoming-ti0-540-series) (registry code 41533, turbo-prop) (OpenAirDocs) - Category: Airplane - Serial number: 32R-7887018 - Year built: 1978 - Airframe hours: 3655 - Engines: Lycoming TIO-540-51AD 300 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Registered owner: Elusive Aviation Inc - Airworthiness certificate: Standard, Commuter - Last inspection: 100 hour, March 4, 2022 - Departed: 1T8, Bulverde, TX - Destination: KDAL, Dallad, TX - Airport: 1T8 - Equipment: Electronic primary flight display, Electronic multifunction display, Auto-pilot, Electronic flight bag or handheld device, ADS-B, Stall warning system, Heads up display, Handheld GPS ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 44; injuries: none; private; airplane ratings: single-engine land; medical: class 3, without waivers/limitations; last flight review May 19, 2021; seat: left; restraint: 3-point; flight hours: 657 total, 488 in this make and model, 541 as pilot in command, 14 in the last 90 days, 2 in the last 30 days, 1 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 190° at 5 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 75 °F, dew point 70 °F - Altimeter: 29.79 inHg - Observed at: KSAT, 13 nm away - METAR: METAR KSAT 091251Z 19005KT 10SM SCT070 SCT250 24/21 A2979 RMK AO2 SLP068 T02390206 $= ## 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 20220909015739A](https://openairdocs.org/incident/20220909015739A), Sep 9, 2022: Piper PA-32RT-300T, Bulverde, TX, Substantial damage. On 09/09/2022 at approximately 06:50, aircraft [privacy data omitted], a Piper PA-32RT-300T, serial number 32R-7887018 departed georgetown municipal airport… ## Docket (4 files) The files NTSB released with the investigation on January 30, 2024, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=105901. 8.6 MB in all. - Pilot/operator aircraft accident report, NTSB form 6120.1 (item 1, PDF, 11 pages, 7.3 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=16089854&FileExtension=pdf&FileName=NTSB%20Form%206120_Redacted-Rel.pdf - Photo (item 2, PDF, 2 pages, 1 photo, 805 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=16089615&FileExtension=pdf&FileName=Investigative%20Photo%201-Rel.pdf - Engine examination (item 3, PDF, 6 pages, 3 photos, 437 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=16089730&FileExtension=pdf&FileName=Engine%20Examination-Rel.pdf - Release of aircraft wreckage, NTSB form 6120.15 (item 4, PDF, 1 page, 83 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=16089740&FileExtension=pdf&FileName=N31981%20Release_Redacted-Rel.pdf 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.