# NTSB FTW95LA127: Israel Aircraft Industries 1124, N66JE, Denver, CO, February 21, 1995 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: February 21, 1995, 08:45 local (15:45 UTC) - Place: Denver, CO - Coordinates: 39.789791, -104.959167 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=39.7898&lon=-104.9592&mi=10 - Phase of flight: [Standing](https://openairdocs.org/ntsb-phases/150) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 2 uninjured - Status: Completed, report December 7, 1995 - Report: Approved by Office Director - Safety recommendations: Yes - NTSB case key (mKey): 19361 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=FTW95LA127 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/19361/pdf - Page: https://openairdocs.org/ntsb/FTW95LA127 ## Probable cause AN OXYGEN LEAK AT THE OXYGEN SYSTEM PRESSURE REDUCER-REGULATOR ASSEMBLY, RESULTING IN A CREW COMPARTMENT FIRE. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Fire, standing - pre-flight - maintenance,service of aircraft/equipment - inadequate, other maintenance personnel - oxygen system - leak (cause) - oxygen system - fire (cause) - oxygen system - contamination ## Analysis DURING PREFLIGHT OF THE AIRPLANE, THE FIRST OFFICER OPENED THE MAIN OXYGEN SUPPLY VALVE IN THE COCKPIT AND HEARD A LOUD HISSING SOUND. ALMOST IMMEDIATELY THEREAFTER, THE COCKPIT WAS ENGULFED IN FLAMES, BUT THE COPILOT WAS ABLE TO ESCAPE. HE EXITED THE AIRPLANE UNINJURED. THE FIRE MELTED THE OXYGEN SYSTEM PRESSURE REDUCER-REGULATOR ASSEMBLY, BURNED A HOLE IN THE RIGHT FORWARD SIDE WALL OF THE AIRPLANE, AND CAUSED SUBSTANTIAL DAMAGE TO THE CABIN INTERIOR BEFORE IT WAS EXTINGUISHED BY RAMP PERSONNEL. A LABORATORY ANALYSIS DISCLOSED THE PRESENCE OF OIL IN A 'DEPOSIT' FOUND ON THE INTERIOR OF THE OXYGEN CYLINDER. ## Factual narrative On February 21, 1995, at 0845 mountain standard time, an Israel Aircraft Industries 1124, N66JE, sustained substantial damage from an onboard fire while standing on the ramp at Stapleton International Airport, Denver, Colorado. The copilot, who was aboard, was not injured. Cabin preparation for a flight later in the day was being conducted at the time of the incident. According to the first officer who was conducting cabin checks with no power on the aircraft, he turned on the oxygen valve, heard a loud hissing sound and an immediate fire occurred. The first officer evacuated the aircraft and local ramp personnel extinguished the fire before the airport fire department arrived. However, the cabin and flight deck were scorched with substantial melting, and a large hole was burned in the pressure vessel in the vicinity of the oxygen regulator. The oxygen regulator was melted in the fire and meaningful examination for function and leaks was not possible. The oxygen bottle was removed and forwarded to Israel Aircraft Industries, Engineering Division, for detailed examination. Their report is attached and provides information that the oxygen bottle contained deposits consisting of phthalates, hydrocarbons, fatty acids and zinc bis (n,n-diethyldithiocarbamate), the latter being documented as a catalyst. Their conclusions were that there was oil present in the oxygen cylinder. A review of maintenance activity on the oxygen cylinder was conducted and records were located which provided information that the oxygen bottle had been tested and cleaned by TEC AIR Services, Northport, New York, on November 4, 1990, and on January 11, 1994. (Copies of work orders are attached.) TEC AIR Services was a Certified Repair Station (CRS) No. MA1R315K. The FAA provided information that TEC AIR Services, had been investigated by the FAA for failing to properly overhaul and repair oxygen cylinder assemblies before returning those items to service. The FAA investigation resulted in repair station certificate revocation. The President of Professional Jet Management, the operator of the incident aircraft, was queried. He stated that he had a Hawker 700 jet, N700AC, which had oxygen bottle service by TEC AIR. This bottle was inspected and the inspection revealed that the bottle was unserviceable due to internal corrosion. Further, the FAA published an Advisory Circular 43-16, dated February 1995. In that publication Mr. Fred Stein, Technical Branch Manager (AEA 230), with the Eastern Regional Office pointed out that TEC AIR, in many instances, may have failed to properly overhaul and repair oxygen cylinder assemblies before returning them to service. ## Aircraft - Registration: [N66JE](https://openairdocs.org/deregistered/N66JE-1995-09-20), registration cancelled 1995-09-20, S/N 326 (OpenAirDocs) - Reported make and model: Israel Aircraft Industries 1124 - Registry model: [Israel Aircraft Industries 1124](https://openairdocs.org/model/israel-aircraft-industries-1124) (registry code 4500102) (OpenAirDocs) - Category: Airplane - Serial number: 326 - Airframe hours: 4098 - Engines: GARRETT 731-3-1G 3700 lbs thrust turbo fan - Damage: Substantial damage - Fire: On-Ground - Flight: Business, Part 91 - Operator: Professional Jet Management - Registered owner: Nje Corporation - Airworthiness certificate: Standard, Transport - Last inspection: Continuous airworthiness, June 7, 1994, 144 hours before - Departed: DEN - Destination: DEN - Airport: DEN, Stapleton International ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 50; commercial, airline transport; airplane ratings: multi-engine land, single-engine land; instrument ratings: airplane; medical: class 1, valid medical--w/ waivers/lim; flight hours: 8,200 total, 1,400 in this make and model, 5,500 as pilot in command, 70 in the last 90 days, 25 in the last 30 days ## Weather - Conditions: Day ## 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 19950221014449A](https://openairdocs.org/incident/19950221014449A), Feb 21, 1995: Israel 1124, Denver, CO, Substantial damage. Oxygen valve in cockpit opened. Hissing sound. Fire erupted. Put out. Oxygen cylinder had oil deposit. 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.