# NTSB FTW96LA405: Israel Aircraft Industries 1125 Westwind Astra, N419MK, Aspen, CO, September 30, 1996 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: September 30, 1996, 12:40 local (18:40 UTC) - Place: Aspen, CO - Coordinates: 39.189628, -106.820503 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=39.1896&lon=-106.8205&mi=10 - Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 3 uninjured - Status: Completed, report February 1, 1997 - Report: Approved by Office Director - NTSB case key (mKey): 19993 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=FTW96LA405 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/19993/pdf - Page: https://openairdocs.org/ntsb/FTW96LA405 ## 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 In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Loss of control - on ground/water, landing - roll - landing gear,anti-skid brake system - corroded (cause) - brakes(normal) - not selected, flightcrew (cause) - directional control - not maintained, flightcrew (cause) - proper alignment - not maintained, flightcrew (cause) - On ground/water collision with object, landing - 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](https://openairdocs.org/aircraft/N419MK), registered now, S/N 066, built 1993 (OpenAirDocs) - Reported make and model: Israel Aircraft Industries 1125 WESTWIND ASTRA (1125 WESTW) - Registry model: [Israel Aircraft Industries 1125 WESTWIND ASTRA](https://openairdocs.org/model/israel-aircraft-industries-1125-westwind-astra) (registry code 4500305) (OpenAirDocs) - Registry engine: [Honeywell TFE731-3C](https://openairdocs.org/engine/honeywell-tfe731-3c) (registry code 33841, turbo-fan) (OpenAirDocs) - Category: Airplane - Serial number: 066 - Airframe hours: 1974 - Engines: Garrett TFE 731-3A 3700 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 ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 57; 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 (OpenAirDocs). - [Accident 19960930047019A](https://openairdocs.org/incident/19960930047019A), Sep 30, 1996: Israel 1125, Aspen, CO, Substantial damage. (-16) At this time the aircraft is still under investigation to see if there was/is a mechanical problem or not which would cause the aircraft to drift to 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.