FTW96LA405

NTSB accident investigation · Israel Aircraft Industries 1125 Westwind Astra · Aspen, CO · September 30, 1996

Accident · No injuriesLimited investigationFinal report
Date
September 30, 1996, 12:40 local (18:40 UTC)
Place
Aspen, CO
Injuries
3 uninjured
Damage
Substantial damage
Phase of flight
Landing
Aircraft
N419MKIsrael Aircraft Industries 1125 Westwind Astra
Weather
Visual (VMC) · Day
Status
Completed · report February 1, 1997
Report
Approved by Office Director
FAA report
19960930047019A
Case key
19993

From the NTSB’s public API. By law, NTSB reports can’t be used as evidence in lawsuits over the accident.

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Probable cause

failure of the right brake antiskid, due to corrosion of a canon plug; and failure of the flight crew to revert to the normal brake system.

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.

Loss of control - on ground/waterLanding - roll
Landing gear,anti-skid brake system - corrodedCause
Brakes(normal) - not selectedFlightcrewCause
Directional control - not maintainedFlightcrewCause
Proper alignment - not maintainedFlightcrewCause
On ground/water collision with objectLanding - roll
Object - airport sign/marker

Analysis

The pilot said the landing was normal. The brake antiskid system was engaged. Braking action decelerated the airplane to 90 kias, then the airplane began drifting left of the runway centerline. Differential braking, full right rudder, and nose wheel steering failed to correct the ground track. The airplane collided with two taxiway signs, the nose landing gear was sheared off, and its strut penetrated the pressure vessel. Temporary repairs were made to the airplane in order to ferry it to a facility where permanent repairs could be made. When electrical power was applied, the right brake antiskid light illuminated. The brake antiskid system was then engaged. During a high speed taxi test, the brake antiskid light remained illuminated. When brakes were applied, the right brake was found to be inoperative. When the antiskid system was disengaged, the brakes operated normally. Post-test examination disclosed the right inboard antiskid generator canon plug was corroded, causing the antiskid to falsely sense a locked brake and automatically releasing it.

Factual narrative

On September 30, 1996, approximately 1240 mountain daylight time, an Israel Aircraft Industries 1125 Westwind Astra, N419MK, was substantially damaged when it collided with two taxiway signs and a runway light during its landing roll at Aspen Colorado. The pilot, copilot, and one passenger were not injured. Visual meteorological conditions prevailed, and an IFR flight plan had been filed for the personal flight conducted under Title 14 CFR Part 91. The flight originated at Chicago, Illinois, on September 30, 1996, approximately 1130 central daylight time.

According to the pilot, the landing was normal. The brake antiskid system was engaged. Normal braking action decelerated the airplane to 90 kias (knots indicated airspeed), then the airplane began drifting left of the runway centerline. Differential braking, full right rudder, and the use of nose wheel steering failed to correct the track. The airplane departed the left side of the runway, and the left main landing gear struck a taxiway sign. The aircraft then struck a second taxiway sign, the nose landing gear was sheared off, and its strut penetrated the pressure vessel.

The cockpit voice recorder (CVR) was recovered from the airplane and sent to the National Transportation Safety Board's CVR laboratory in Washington, DC, for examination and readout. The CVR specialist reported that although the tape recording was of good quality, no definitive information was obtained.

Temporary repairs were made to the airplane so that it could be ferried to Denver, Colorado, where permanent repairs would be made. When electrical power was applied in preparation for the ferry flight, the right brake antiskid light illuminated. The brake antiskid system was then engaged. During a high speed taxi test, it was noted the antiskid light remained illuminated. The pilot applied brakes and confirmed that the right brake was inoperative. The pilot deactivated the brake antiskid system, applied brakes, and found the brakes operated properly. Post test examination disclosed the right inboard antiskid generator canon plug was corroded. It was the opinion of Westwind Astra engineers and the airplane operator that this corrosion caused the brake antiskid system to falsely sense a locked right brake and automatically released it. They surmised that when brakes were applied during the landing roll, only the left brake engaged, causing the airplane to drift off the left side of the runway.

Aircraft

Registration
N419MK
Reported as
Israel Aircraft Industries 1125 Westwind Astra (1125 WESTW)
Category
Airplane
Serial number
066
Airframe hours
1,974
Engine
Garrett TFE 731-3A, 3,700 lbs thrust, turbo fan
Damage
Substantial damage
Flight
Personal · Part 91
Operator
Emery Air Charter
Registered owner
K&M Flight Corporation
Airworthiness certificate
Standard, Normal
Last inspection
AAIP · September 5, 1996 · 60 hours before
Departed
MDW · Chicago, IL
Destination
ASE
Flight plan
IFR
Airport
ASE · Aspen-Pitkin Co/Sardy Fld, runway 15, 7,004 × 100 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
57
Certificate
Commercial
Airplane ratings
Single-engine land, Multi-engine land
Instrument ratings
Airplane
Medical
Class 1, Valid Medical--w/ waivers/lim
Seat
Left
Flight hours
4,008 total · 207 in this make and model · 3,348 as pilot in command · 95 in the last 90 days · 24 in the last 30 days · 3 in the last 24 hours

Weather

Conditions
Visual (VMC) · Day
Wind
200° at 4 knots
Visibility
30 statute miles
Lowest ceiling
None
Temperature
68 °F, dew point 25 °F
Altimeter
30.00 inHg
Observed at
ASE

FAA reports on this event · 1

The FAA’s own accident and incident reports, matched to the aircraft by N-number and date.