# NTSB DEN93IA005: Mcdonnell Douglas DC-9-82, N72822, Denver, CO, October 13, 1992

- Type: NTSB incident investigation
- Classification: Incident · No injuries · Incident investigation · Final report
- Date: October 12, 1992, 20:01 local (Oct 13, 1992, 02:01 UTC)
- Place: Denver, CO
- Coordinates: 39.760784, -104.920364 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=39.7608&lon=-104.9204&mi=10
- Phase of flight: [Unknown](https://openairdocs.org/ntsb-phases/990) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 88 uninjured
- Status: Completed, report June 30, 1993
- Report: Approved by Office Director
- NTSB case key (mKey): 18250
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=DEN93IA005
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/18250/pdf
- Page: https://openairdocs.org/ntsb/DEN93IA005

## Probable cause

AN INADVERTENT ATTEMPT, BY UNKNOWN PERSONS, TO START THE APU WHICH HAD BEEN PLACARDED AS INOPERATIVE.  FACTORS WERE: INADEQUATE PROCEDURES IN RENDERING THE APU INCAPABLE OF BEING STARTED WHEN INOPERATIVE.

## Analysis

WHILE IN CRUISE FLIGHT, THE 'RIGHT REVERSER ACCUMULATOR LOW' CAUTION LIGHT ILLUMINATED.  EXAMINATION FOLLOWING LANDING REVEALED THAT THE AUXILIARY POWER UNIT (APU) TURBINE WHEEL HAD SEPARATED IN AN UNCONTAINED FAILURE, AND HAD DAMAGED NUMEROUS COMPONENTS IN THE COMPARTMENT BELOW THE NUMBER TWO ENGINE PYLON.  THE APU HAD BEEN PLACARDED AS INOPERATIVE TWO DAYS PRIOR TO THE INCIDENT.  THE INVESTIGATION DID NOT REVEAL WHEN AN INADVERTENT ATTEMPT TO START THE APU HAD OCCURRED, BUT DID REVEAL THAT NO PROCEDURES, OTHER THAN THE INOPERATIVE PLACARD, WERE IN PLACE TO PREVENT START ATTEMPTS.

## Sequence of events

In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf).

- Airframe/component/system failure/malfunction, unknown
  - auxiliary power unit - inoperative
  - procedures/directives - not followed, unknown (cause)
  - procedure inadequate, company/operator management (contributing factor)

## Aircraft

- Registration: [N72822](https://openairdocs.org/deregistered/N72822-2005-09-26), registration cancelled 2005-09-26, S/N 49482, built 1986 (OpenAirDocs)
- Reported make and model: MCDONNELL DOUGLAS DC-9-82
- Registry model: [Mcdonnell Douglas DC-9-82(MD-82)](https://openairdocs.org/model/mcdonnell-douglas-dc-9-82-md-82) (registry code 3022082) (OpenAirDocs)
- Registry engine: [Pratt & Whitney JT8D series](https://openairdocs.org/engine/pratt-whitney-jt8d-series) (registry code 52053, turbo-jet) (OpenAirDocs)
- Category: Airplane
- Serial number: 49482
- Airframe hours: 19807
- Engines: P&W JT8D-217A 20000 lbs thrust turbo jet
- Damage: Minor damage
- Flight: Part 121
- Operator: Continental Airlines, Inc.
- Registered owner: Continental Airlines, Inc.
- Airworthiness certificate: Standard, Transport
- Last inspection: Continuous airworthiness, April 1, 1992, 1,681 hours before
- Departed: IAH, HOUSTON, TX
- Flight plan: IFR

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 45; airline transport; airplane ratings: single-engine land, multi-engine land; instrument ratings: airplane; medical: class 1, valid medical--no waivers/lim.; seat: left; flight hours: 13,300 total, 9,000 in this make and model, 7,000 as pilot in command, 180 in the last 90 days, 60 in the last 30 days

## Weather

- Conditions: Visual (VMC), Night/bright
- Lowest ceiling: none

## FAA reports on this event (1)

The FAA's own accident and incident reports, matched to the aircraft by N-number and date (OpenAirDocs).

- [Incident 19921012047169I](https://openairdocs.org/incident/19921012047169I), Oct 12, 1992: Doug DC982, Denver, CO, Minor damage. Right reverser accumulator low light on. Continued to destination. Found APU turbine had separated.

## Other investigations on N72822 (1)

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.

- [NTSB DEN93FA049](https://openairdocs.org/ntsb/DEN93FA049), Apr 27, 1993: Mcdonnell Douglas DC-9-82 (N72822), Denver, CO, substantial damage. Probable cause: A VIBRATION IN THE RIGHT MAIN LANDING GEAR, FOR UNDETERMINED REASONS, WHICH RESULTED IN COLLAPSE OF THE RIGHT MAIN GEAR. A FACTOR WAS FAILURE OF THE PILOT IN COMMAND TO ENSURE DEPLOYMENT OF 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.