McDonnell Douglas DC-10-10F N68058

Summary

On 7 August 1999 at about 18:45 local time, a McDonnell Douglas DC-10-10F registered N68058, operated by Federal Express Corporation, was involved in an accident near Memphis, Tennessee, United States. 5 people were on board and nobody was injured. The aircraft was substantially damaged. The NTSB has published a probable cause for this accident; it is quoted in full below.

Date

7 August 1999 at 18:45

Classification

Accident

Location

Memphis, Tennessee, United States

Nearest airport

Memphis International (MEM)

Coordinates

35.0300, -89.9296

Aircraft

McDonnell Douglas DC-10-10F

Registration

N68058

Category

Airplane

Engines

3

Operator

Federal Express Corporation

Operating rule

Part 121: Air Carrier

Phase of flight

Not recorded

Route

Los Angeles → Unknown

Aircraft damage

Substantial

Weather

VMC

Light

Day

NTSB number

MIA99LA220

Nobody was injured.

The inadequate design by the airplane manufacturer for using bolts to secure the inboard trailing edge flap that are susceptible to stress corrosion cracking. Also, the stress corrosion cracking failure of the four H-11 bolts that secure the left inboard trailing edge flap to the outboard hinge which allowed the separation of the flap and vane while on final approach.

Quoted verbatim from the NTSB record. This site does not paraphrase or interpret it.

Read the full NTSB narrative

While on final approach with full flaps selected and indicated, the left inboard trailing edge flap and vane separated. The autopilot was disconnected and approximately 1/2 right aileron input was needed to counter the left banking tendency. The landing was reported to be firm but with less 'controllability'. Structural damage occurred to the left side of the fuselage due to flap and/or vane contact. The four H-11 type bolts of the forward attach point of the outboard hinge of the left inboard trailing edge flap failed due to stress corrosion cracking. Chromium was detected in the fracture origin of bolts Nos. 1-3; no determination was made as to why chromium was present. The two H-11 type bolts of the aft attach point of the outboard hinge of the left inboard trailing edge flap failed due to ductile overload. No material or processing discrepancies were found. H-11 bolts are susceptible to stress corrosion cracking. The FDR readout indicated that the maximum left roll was 8.09 degrees and flap extension speed was exceeded on landing No. 1 for approximately 13 seconds when the flaps were extending from 16 to 20 degrees. No flap overspeed protection is afforded in that range.

Quoted verbatim from the NTSB record.