Summary
On June 15, 2007, a Nelson Murphy SR3500 Moose (N623AM) was involved in an accident near Roche Harbor, WA. The accident resulted in 1 serious injury, with 3 people uninjured out of 4 aboard. The aircraft sustained substantial damage.
The National Transportation Safety Board determined the probable cause of this accident to be: The jamming of the left brake during landing. A factor was the kit manufacturer's design of the brake system.
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.
This accident is documented in NTSB report SEA07CA159. AviatorDB cross-references NTSB investigation data with FAA registry records to provide comprehensive safety information for aircraft N623AM.
Accident Details
Probable Cause and Findings
The jamming of the left brake during landing. A factor was the kit manufacturer's design of the brake system.
Aircraft Information
Registered Owner (Historical)
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 homebuilt airplanes manufactured from the same kit.
Data Source
Data provided by the National Transportation Safety Board (NTSB). For more information on this event, visit the NTSB Records Search website. NTSB# SEA07CA159