- Date
- July 20, 1996, 16:30 local (23:30 UTC)
- Place
- Cottage Grove, OR
- Injuries
- 2 uninjured
- Damage
- Substantial damage
- Phase of flight
- Takeoff
- Aircraft
- N235WCConkey/Wapelhorst Lancair 235
- Weather
- Visual (VMC) · Day
- Status
- Completed · report May 23, 1997
- Report
- Approved by Office Director
- FAA report
- 19960720019159A
- Case key
- 42424
From the NTSB’s public API. By law, NTSB reports can’t be used as evidence in lawsuits over the accident.
On this page
Probable cause
release of the main landing gear locking mechanism for undetermined reason(s).
Sequence of events
NTSB’s coding before 2008: each occurrence and phase of flight, and the causes and factors under it. The codes are defined in NTSB’s coding manual.
Analysis
During the takeoff roll on runway 33, the left main landing gear collapsed as the aircraft was accelerating through about 55 to 60 knots. The pilot/co-owner of the aircraft reported that he was unable to identify any mechanical malfunction which have would allowed the left main gear to collapse. He also reported that the gear down lights were illuminated during the takeoff checklist. The reason for the release of the left main gear from the down and locked position could not be determined. However, a 5 to 10 knot quartering right crosswind existed at the time of the takeoff. Once the aircraft settled onto the left wing, the pilot was unable to maintain directional control, and the aircraft slid into another aircraft that was parked off the runway.
Factual narrative
On July 20, 1996, approximately 1600 Pacific daylight time, a Conkey/Wapelhorst homebuilt Lancair 235, N235WC, registered to and being flown by a private pilot, was substantially damaged when the left main landing gear collapsed during the takeoff roll at the Cottage Grove airport, Cottage Grove, Oregon. The pilot and passenger were uninjured. Visual meteorological conditions prevailed and no flight plan had been filed. The flight, which was to have been local, was to be operated under 14CFR91.
The pilot reported that he commenced the takeoff roll on runway 33, with an estimated wind of 05-10 knots from 010 degrees. As the aircraft accelerated through 55-60 knots the aircraft's left wing suddenly dropped. The pilot aborted the takeoff and the aircraft slid approximately 200 feet before leaving the west side of the runway and eventually impacting a parked Stinson 30 feet west of the runway.
The pilot reported that he "could not determine any failures that (would have) caused the left wheel to collapse inboard." The Lancair main landing gear fold inboard into wheel wells in the lower fuselage. They are normally held in the down and locked position by hydraulic pressure.
The pilot reported observing that all three gear down lights were illuminated during the takeoff checklist.
Aircraft
- Registration
- N235WC
- Reported as
- Conkey/Wapelhorst Lancair 235 (LANCAIR 23)
- Category
- Airplane, amateur-built
- Serial number
- 001
- Airframe hours
- 328
- Engine
- Lycoming O-235-L2C, 125 horsepower, reciprocating
- Damage
- Substantial damage
- Flight
- Personal · Part 91
- Operator
- Conkey, Denis, R.
- Registered owner
- Conkey & Wapelhorst
- Airworthiness certificate
- Special, Experimental (Special)
- Last inspection
- Annual · July 18, 1996 · 6 hours before
- Departed
- 61S
- Airport
- 61S · Cottage Grove State, runway 33, 3,200 × 60 ft, asphalt
Matched to the registry by N-number and the event date; the registry’s history has gaps, so older matches can be wrong. Compare the reported make and model.
Flight crew
As NTSB recorded them. NTSB leaves out names.
- Role
- Pilot
- Age
- 44
- Certificate
- Private
- Airplane ratings
- Single-engine land
- Medical
- Class 2, Valid Medical--w/ waivers/lim
- Seat
- Left
- Flight hours
- 2,615 total · 222 in this make and model · 28 in the last 90 days · 8 in the last 30 days · 5 in the last 24 hours
Weather
- Conditions
- Visual (VMC) · Day
- Wind
- 10° at 10 knots
- Visibility
- 20 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.
Other investigations on N235WC · 1
Matched to the same aircraft by N-number and date.