# NTSB SEA07CA159: Nelson Murphy SR3500 Moose, N623AM, Roche Harbor, WA, June 15, 2007 - Type: NTSB accident investigation - Classification: Accident · Serious injuries · Data collection · Final report - Date: June 14, 2007, 18:00 local (Jun 15, 2007, 01:00 UTC) - Place: Roche Harbor, WA - Coordinates: 48.620277, -123.142219 - Nearby events: https://openairdocs.org/map.md?lat=48.6203&lon=-123.1422&mi=10 - Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping) - Highest injury: Serious injuries - Injuries: 1 serious, 3 uninjured - Status: Completed, report August 30, 2007 - Report: Approved by Office Director - NTSB case key (mKey): 65997 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=SEA07CA159 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/65997/pdf - Page: https://openairdocs.org/ntsb/SEA07CA159 ## Probable cause The jamming of the left brake during landing. A factor was the kit manufacturer's design of the brake system. ## 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 - jammed (cause) - ground loop/swerve - intentional, pilot in command - acft/equip,inadequate design, kit manufacturer (contributing factor) - Main gear collapsed, landing - roll - terrain condition - dirt bank/rising embankment ## Analysis The pilot said he was landing on runway 07 with a 5-knot right crosswind. He said that shortly after touchdown, the aircraft started a slight drift to the right. The pilot said he applied left rudder to compensate and felt a "thunk" as the left rudder pedal locked forward, over center, underneath the brake pedal, which prevented the use of the left brake. The aircraft briefly lurched to the left. He applied hard right rudder, but with no apparent effect. He next applied right brake and intentionally ground looped the aircraft to prevent going down an embankment on the south side of the runway. The airplane's left main landing gear collapsed, followed by the left wing, left aileron, and forward fuselage being wrinkled and bent. The pilot said that the rudder/brake pedal assembly has only one master cylinder for the braking system and it is located on the right hand side. He said there is a mechanical linkage from the right to the left, which is prone to jamming in certain rudder pedal deflections. He said that other pilot's have reported this problem with their amateur-built airplanes manufactured from the same kit. ## Factual narrative The pilot said he was landing on runway 07 with a 5-knot right crosswind. He said that shortly after touchdown, the aircraft started a slight drift to the right. The pilot said he applied left rudder to compensate and felt a "thunk" as the left rudder pedal locked forward, over center, underneath the brake pedal, which prevented the use of the left brake. The aircraft briefly lurched to the left. He applied hard right rudder, but with no apparent effect. He next applied right brake and intentionally ground looped the aircraft to prevent going down an embankment on the south side of the runway. The airplane's left main landing gear collapsed, followed by the left wing, left aileron, and forward fuselage being wrinkled and bent. The pilot said that the rudder/brake pedal assembly has only one master cylinder for the braking system and it is located on the right hand side. He said there is a mechanical linkage from the right to the left, which is prone to jamming in certain rudder pedal deflections. He said that other pilot's have reported this problem with their homebuilt airplanes manufactured from the same kit. ## Aircraft - Registration: [N623AM](https://openairdocs.org/deregistered/N623AM-2011-04-26), registration cancelled 2011-04-26, S/N SR123, built 2006 (OpenAirDocs) - Reported make and model: Nelson Murphy SR3500 Moose - Registry model: [Nelson Miguel MURPHY SR3500 MOOSE](https://openairdocs.org/model/nelson-miguel-murphy-sr3500-moose) (registry code 05621SN) (OpenAirDocs) - Registry engine: [Vedeneyev M14P](https://openairdocs.org/engine/vedeneyev-m14p) (registry code 63601, reciprocating) (OpenAirDocs) - Category: Airplane, amateur-built - Serial number: SR123 - Engines: Vendeneyev M-14P 360 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Registered owner: Miguel E. Nelson - Airworthiness certificate: Special, Experimental (Special) - Departed: 74S, Anacortes, WA - Destination: WA09, Roche Harbor, WA - Airport: WA09, Roche Harbor Airport, runway 07, 3,593 × ft, asphalt ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 47; injuries: serious; flight engineer, airline transport, commercial; airplane ratings: multi-engine land, single-engine land; instrument ratings: airplane; medical: class 1; flight hours: 10,265 total, 57 in this make and model, 95 in the last 90 days, 57 in the last 30 days, 1 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 130° at 5 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 63 °F, dew point 45 °F - Altimeter: 30.13 inHg ## 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 20070614012609A](https://openairdocs.org/incident/20070614012609A), Jun 14, 2007: Amtr SR3500MOOSE, Roche Harbor, WA, Substantial damage. (-23) The pilot stated that while landing on runway 07 at Roche Harbor with a very slight crosswind that touchdown was normal and on the centerline of 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.