Mcminnville Airport
Aircraft Accident/Incident Report

Mcminnville, Oregon 97128
Monday, May 13, 2013 12:45 PDT

NTSB Narrative Summary Released at Completion of Accident

The crew of the twinjet reported that the positioning flight after maintenance was uneventful. However, during the landing roll at their home base, the thrust reversers, steering, and braking systems did not respond. As the airplane approached the end of the runway, the pilot activated the emergency braking system; however, the airplane overran the end of the runway, coming to rest in a ditch. None of the three occupants were injured, but the airplane sustained substantial damage to both wings and the fuselage. Two squat switches provided redundancy within the airplane’s electrical system and were configured to prevent inadvertent activation of the thrust reversers and nosewheel steering during flight and to prevent the airplane from landing with the brakes already applied. Because postaccident examination revealed that the squat switch assemblies on the left and right landing gear struts were partially detached from their mounting pads such that both switches were deactivated, all of these systems were inoperative as the airplane landed. The switch assemblies were undamaged, and did not show evidence of being detached for a long period of time. The brakes and steering were working during taxi before departure, but this was most likely because either one or both of the switches were making partial contact at that time. Therefore, it was most likely that the squat switch assemblies were manipulated on purpose during maintenance in an effort to set the airplane’s systems to “air mode.” Examination of the maintenance records did not reveal any recent procedures that required setting the airplane to air mode, and all mechanics involved in the maintenance denied disabling the switches. Mechanics did, however, miss two opportunities to identify the anomaly, both during the return-to-service check and the predelivery aircraft and equipment status check. The anomaly was also missed by the airplane operator’s mechanic and flight crew who performed the preflight inspection. The airplane’s emergency braking system was independent of the squat switches and appeared to operate normally during a postaccident test. Prior to testing, it was noted that the emergency brake gauge indicated a full charge; therefore, although evidence suggests that the emergency brake handle was used, it was not activated with enough force by the pilot. The pilot later conceded this fact and further stated that he should have used the emergency braking system earlier during the landing roll. The airplane was equipped with a cockpit voice recorder (CVR), which captured the entire accident sequence. Analysis revealed that the airplane took just over 60 seconds to reach the runway end following touchdown, and, during that time, two attempts were made by the pilot to activate the thrust reversers. The pilot stated that as the airplane approached the runway end, the copilot made a third attempt to activate the thrust reversers, which increased the engine thrust, and thereby caused the airplane to accelerate. Audio captured on the CVR corroborated this statement.

NTSB Probable Cause Narrative

Failure of maintenance personnel to reattach the landing gear squat switches following maintenance, which rendered the airplane's steering, braking, and thrust reverser systems inoperative during landing. Contributing to the accident were the failure of both the maintenance facility mechanics and the airplane operator's mechanic and flight crew to identify the error during postmaintenance checks, a failure of the airplane's pilot to apply the emergency brakes in a timely manner, and the copilot's decision to attempt to engage the thrust reversers as the airplane approached the runway end despite multiple indications that they were inoperative and producing partial forward, rather than reverse, thrust.

Event Information

Type of Event Accident
Event Date 5/13/2013
Event Day of the Week Monday
Time of Event 1245
Event Time Zone Pacific Daylight Time
Event City McMinnville
Event State OREGON
Event Country --
Zipcode of the event site 97128
Event Date Year 2013
Event Date Month 5
MidAir Collision Indicator No
On Ground Collision occurred ? No
Event Location Latitude 451125N
Event Location Longitude 1230905W
Event Location Airport McMinnville
Event Location Nearest Airport ID MMV
Indicates whether the acc/inc occurred off or on an airport On Airport
Distance from airport in statute miles 0.5
Degrees magnetic from airport 220
Airport Elevation 163
Weather Briefing Completeness --
Investigator's weather source Weather Observation Facility
Time of the weather observation 1153 Pacific Daylight Time
Direction of event from weather observation facility (degrees) --
Weather Observation Facility ID MMV
Elevation of weather observation facility 163
Distance of event from weather observation facility (units?) 0
Time Zone of the weather observation PDT
Lighting Conditions Day
Lowest Ceiling Height 3100
Lowest Non-Ceiling Height 2600
Sky/Lowest/Cloud Conditions Scattered
Sky Condition for Lowest Ceiling Broken
Visibility Runway Visual Range (Feet) --
Visibility Runway Visual Value (Statute Miles) --
Visibility (Statute Miles) 10
Air Temperature at event time (in degrees celsius) 17
Dew Point at event time (in degress fahrenheit) 12
Wind Direction (degrees magnetic) 220
Variable Wind Indicator Wind direction could be determined
Wind Speed (knots) 7
Wind Velocity Indicator --
Wind Gust Indicator Not Gusting
Wind Gust (knots) --
Altimeter Setting at event time (in. Hg) 30.08
Density Altitude (feet) --
Intensity of Precipitation --
METAR weather report METAR KMMV 131853Z AUTO 22007KT 10SM SCT026 BKN031
Event Highest Injury None
On Ground, Fatal Injuries --
On Ground, Minor Injuries --
On Ground, Serious Injuries --
Injury Total Fatal --
Injury Total Minor --
Injury Total None 3
Injury Total Serious --
Injury Total All --
Investigating Agency NTSB
NTSB Docket Number (internal use) 33300
NTSB Notification Source FAA ROC
NTSB Notification Date --
NTSB Notification Time --
Fiche Number and/or location -used to find docket information --
Date of most recent change to record Oct 9 2014 1:24PM
User who most recently changed record sime1
Basic weather conditions Visual Meteorological Cond
FAA District Office --

Aircraft Involved

Aircraft #1

Aircraft Registration Number N22MS
NTSB Number WPR13FA227
Missing Aircraft Indicator --
Federal Aviation Reg. Part Part 91: General Aviation
Type of Flight Plan filed IFR
Flight plan Was Activated? Yes
Damage Substantial
Aircraft Fire None
Aircraft Explosion None
Aircraft Manufacturer's Full Name GATES LEARJET CORP.
Aircraft Model 35A
Aircraft Series Identifier --
Aircraft Serial Number 209
Certified Max Gross Weight 18300
Aircraft Category Airplane
Aircraft Registration Class --
Aircraft is a homebuilt? No
Flight Crew Seats --
Cabin Crew Seats 2
Passenger Seats 8
Total number of seats on the aircraft 10
Number of Engines 2
Fixed gear or retractable gear Retractable
Aircraft, Type of Last Inspection Continuous Airworthiness
Date of Last Inspection May 13 2013 12:00AM
Airframe hours since last inspection 2.2
Airframe Hours 15047.1
ELT Installed Yes
ELT Activated No
ELT Aided Location of Event Site Unknown
ELT Type C126
Aircraft Owner Name EVERGREEN EQUITY INC
Aircraft Owner Street Address --
Aircraft Owner City MCMINNVILLE
Aircraft Owner State OR
Aircraft Owner Country USA
Aircraft Owner Zipcode 97128-9402
Operator is an individual? No
Operator Name Evergreen International Aviation Inc.
Operator Same as Owner? No
Operator Is Doing Business As --
Operator Address Same as Owner? No
Operator Street Address --
Operator City MCMINNVILLE
Operator State OR
Operator Country USA
Operator Zip code 97128-9402
Operator Code EIAA
Owner has at least one certificate Yes - certificate holder
Other Operator of large aircraft? --
Certified for Part 133 or 137 Operation --
Operator Certificate Number EIAA103A
Indicates whether an air carrier operation was scheduled or not --
Indicates Domestic or International Flight --
Operator carrying Pax/Cargo/Mail --
Type of Flying (Per_Bus / Primary) Positioning
Second Pilot on Board Yes
Departure Point Same as Event No
Departure Airport Code GJT
Departure City Grand Junction
Departure State CO
Departure Country USA
Departure Time 1145
Departure Time Zone MDT
Destination Same as Local Flt crash at destination city
Destination Airport Code MMV
Destination City McMinnville
Destination State OR
Destination Country USA
Specific Phase of Flight --
Report sent to ICAO? --
Evacuation occurred --
Date of most recent change to record Sep 30 2014 8:35PM
User who most recently changed record sime1
Since inspection or accident Last Inspection
Event Location Runway Number and Location 22
Runway Length 5420
Runway Width 150
Sight Seeing flight No
Air Medical Flight No
Medical Flight --