# NTSB SEA99LA131: Piper PA-23-250, N65PR, Snohomish, WA, July 12, 1999 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: July 11, 1999, 20:10 local (Jul 12, 1999, 03:10 UTC) - Place: Snohomish, WA - Coordinates: 47.940799, -122.000358 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=47.9408&lon=-122.0004&mi=10 - Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 6 uninjured - Status: Completed, report January 18, 2001 - Report: Approved by Office Director - NTSB case key (mKey): 46992 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=SEA99LA131 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/46992/pdf - Page: https://openairdocs.org/ntsb/SEA99LA131 ## Probable cause Brake system failure due to the presence of air bubbles in the hydraulic fluid. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Airframe/component/system failure/malfunction, landing - roll - landing gear,normal brake system - failure (cause) - On ground/water collision with object, landing - roll - object - vehicle ## Analysis The pilot reported that the touchdown and rollout were normal for about 300 feet. The pilot stated that as he applied the brakes, the left brake failed and the airplane swerved to the right and off the side of the runway. Due to people and equipment near the runway, and in the aircraft's path, the pilot utilized nose wheel steering and right throttle control to redirect the aircraft. The aircraft continued about 80 feet over freshly graded terrain before entering an open field covered with tall grass. The aircraft collided with a ditch and subsequently an abandoned truck before coming to rest. Shortly after the accident, the brake system was inspected. It was found that the left brake pedal would make full travel with no apparent braking action. After applying pumping action, there was a gradual rise of the pedal and braking action. Further inspection of the system did not reveal any mechanical failures or malfunctions. The brake lines were then bled and a considerable amount of air bubbles were noted. ## Factual narrative On July 11, 1999, at 2010 Pacific daylight time, a Piper PA-23-250, N65PR, registered to Skycrab Aircraft Sales, and operated by the pilot as a 14 CFR Part 91 personal flight, experienced a brake malfunction during the landing roll at Harvey Airfield, Snohomish, Washington. The airplane veered off the runway and collided with a ditch and parked vehicle. Visual meteorological conditions prevailed at the time and no flight plan was filed. The airplane was substantially damaged. The private pilot and his five passengers were not injured. The flight departed from Wilbur, Washington, about one hour and 15 minutes prior to the accident. During a telephone interview and subsequent written statement, the pilot reported that touchdown and roll out were normal for about 300 feet. The pilot stated that as he was applying braking action, the left side brake failed and the airplane swerved to the right and off the side of the runway. The pilot reported that there were people and equipment in the aircraft's path so he utilized nose wheel steering and right throttle control to redirect the aircraft. The aircraft continued about 80 feet over freshly graded terrain before entering an open field covered with tall grass. The aircraft collided with a ditch and subsequently an abandoned truck that was parked in the field, before coming to rest. Shortly after the accident, a mechanic inspected the brake system and reported that initial inspection of the left brake showed that the left pedal would make full travel with no apparent braking action. The mechanic reported that with pumping action, there was a gradual rise of the pedal and braking action. The mechanic checked and confirmed that the reservoir was full of fluid. The mechanic also checked and confirmed that no leaks were evident in the fluid-carrying lines, master cylinders, parking brake cylinders and brake assemblies. The mechanic reported that the brake pedals showed no abnormal wear or looseness at the attach points. The mechanic then bled the brake lines and reported that considerable amounts of air bubbles were noted. After the lines were clear of the air bubbles, the pedal would make one-third to one-half travel, with braking, then on the release and reapplication, the pedal was at the top. The left brake and pedal were then disassembled. The mechanic noted minimal wear to the brake pads, and the brake rotor was not excessively grooved or worn. ## Aircraft - Registration: [N65PR](https://openairdocs.org/deregistered/N65PR-2012-11-13), registration cancelled 2012-11-13, S/N 277405289, built 1974 (OpenAirDocs) - Reported make and model: Piper PA-23-250 - Registry model: [Piper PA-23-250](https://openairdocs.org/model/piper-pa-23-250) (registry code 7102308) (OpenAirDocs) - Registry engine: [Lycoming IO-540 series](https://openairdocs.org/engine/lycoming-io-540-series) (registry code 41530, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 277405289 - Engines: Lycoming IO-540-C4B5 250 horsepower reciprocating - Damage: Substantial damage - Fire: Unknown - Flight: Personal, Part 91 - Operator: William P. Morgan - Registered owner: Skycrab Aircraft Sales Inc. - Airworthiness certificate: Standard, Normal - Last inspection: Annual, May 28, 1999 - Departed: 2S8, WILBUR, WA - Destination: S43 - Airport: S43, Harvey Airfield, runway 32, 2,660 × 36 ft, asphalt ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 53; private; airplane ratings: multi-engine land, single-engine land; instrument ratings: airplane; medical: class 3, valid medical--no waivers/lim.; seat: left; flight hours: 1,558 total, 115 in this make and model, 1,555 as pilot in command, 35 in the last 90 days, 16 in the last 30 days ## Weather - Conditions: Visual (VMC), Day - Wind: calm - Visibility: 50 statute miles - Lowest ceiling: none - Temperature: 75 °F ## 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 19990712043769A](https://openairdocs.org/incident/19990712043769A), Jul 12, 1999: Piper PA23250, Snohomish, WA, No damage. (-23) Pilot experienced LH brake failure after approx. 300 feet of landing rollout. Pilot veered left to avoid bystanders and down a 3 ft embankment then… 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.