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Aviation safety reports, made easier to study

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March 25, 1998 · Mcdonnell Douglas DC-10-10 · N1836U

Denver, CO

Overview

Report Status
Final with probable cause
Event Type
Incident
Date
March 25, 1998
Injury Outcomes
No injuries (299 uninjured)
Location
Denver, CO
Aircraft
Mcdonnell Douglas DC-10-10
Tail Number
N1836U
Injuries
None
Aircraft Damage
Minor
NTSB Number
FTW98IA158

While on takeoff roll, the left number 2 main tire tread separated from the casing. Part of the tire went through the number one engine and another portion punctured the left wing. The crew operated the number one engine at reduced power due to vibration and after dumping fuel returned to the departure airport. A precautionary landing was performed and the passengers were deplaned and bussed to the terminal. Aircraft damage was foreign object damage to the number one engine and holes in the lower wing skin adjacent to the left main landing gear wheel well. Laboratory examination of the tire provided evidence that the failure was due to fatigue due to overheat caused by multiple retreading of the tire.

NTSB Probable Cause

The total failure of one main landing gear tire.

Full Narrative

On March 24, 1998, at 2008 mountain daylight time, a McDonnell Douglas DC-10-10, N1836U, operated by United Airlines as flight 1197, from Denver, Colorado, to Seattle, Washington, sustained minor damage during takeoff roll when a tire failed. None of the 299 persons aboard the aircraft were injured. The flight was operating under Title 14 CFR Part 121 and an IFR flight plan was filed. Visual meteorological conditions prevailed. The investigation provided information that during takeoff roll the number 2 left main tire failed. Part of the tire was ingested into the number 1 engine and part went into the left main wheel well. The flight deck crew operated the number one engine at reduced power due to vibration, and the flight returned to Denver, landing at 1834, after dumping 8,400 pounds of fuel. Following landing, the brakes froze due to overheating and the passengers were deplaned and taken to the terminal via bus. After the left main landing gear wheels were replaced, the aircraft was towed to a United Airlines hangar where repairs were made. Postincident examination provided evidence of foreign object damage to the number one engine and two holes in the lower left wing skin above the left main landing gear wheel well. At the request of the Safety Board Investigator-In-Charge, an engineering analysis on the failed tire was conducted by United Airlines Engineering, utilizing Michelin/Gooddrich Aircraft Tire Corporation's failure analysis laboratory. According to the attached failure analysis report, the tire failed as a result of elevated temperature and high levels of fatigue "probably" due to repeated retreading of the tire. As a precautionary measure, Michelin/Goodrich proposed that 50X20-20 DC-10 tires be limited to two retreads (R-2). United agreed and ceased to use tires which had more than the second retread. In addition, Michelin/Goodrich ceased to ship 50X20-20 tires which had more then the R-2 retread to its customer consignment points.

Flight

Event TypeIncident
Event Time19:08 MST
Nearest AirportDenver International (0nm)
Runway17L
Runway Length12000 ft
Runway Width150 ft
Flight Plan FiledIFR
Aircraft FireNo
Aircraft ExplosionNo

Aircraft

AircraftMcdonnell Douglas DC-10-10
Tail NumberN1836U
Aircraft CategoryAir
DamageMinor
Operating RulePart 121
Engines3
Engine TypeTurbofan
Engine DetailsGe · CF6-6 · Turbofan · 40000
Seats299

People & Injuries

Injury SummaryNo injuries (299 uninjured)
Fatal0
Serious0
Minor0
Uninjured299
Total299
Crew 1Age 56 · First Class

Conditions

ConditionsVMC
LightDark Night
Wind60° @ 6 kt
Visibility10 sm
CeilingNone
Temperature / Dew Point64 F / 34 C
Altimeter29.00 inHg
Observation Time02:53
Weather SourceWFAC

Appendix: Source Data