Teschendorf CASSUTT SPORT N86T

Summary

On 20 March 1997 at about 23:35 local time, a Teschendorf CASSUTT SPORT registered N86T was involved in an accident near Stilwell, Oklahoma, United States. One person was on board and one died. The aircraft was destroyed. The NTSB has published a probable cause for this accident; it is quoted in full below.

Date

20 March 1997 at 23:35

Classification

Accident

Location

Stilwell, Oklahoma, United States

Nearest airport

Stilwell/Cherokee Nation (O11)

Coordinates

35.8100, -94.6297

Aircraft

Teschendorf CASSUTT SPORT

Registration

N86T

Category

Airplane

Engines

1

Operator

Not recorded

Operating rule

Part 91: General Aviation

Purpose of flight

Personal

Phase of flight

Not recorded

Route

Cookson → Unknown

Aircraft damage

Destroyed

Weather

VMC

Light

Day

NTSB number

FTW97FA135

1 person died.

failure of the right wing spar and/or debonding of the right wing skin, which resulted in separation of the wing skin and a portion of the right wing, during high speed flight. Factors related to the accident were: previous wing damage and inadequate maintenance by other (unknown) personnel.

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

Read the full NTSB narrative

The pilot (plt) departed Cookson, OK, in a homebuilt aircraft (acft) for an approximate 30 minute flight to Stilwell, OK. Witnesses at Stilwell said he made a low pass on a northerly heading (about 50 ft off the ground) at a high rate of speed. One witness estimated the acft was traveling faster than 200 mph, when he saw the acft's right wing skin separate from the acft. The right wing then came off. The acft was observed to roll several times & travel about 1100 ft before it impacted the ground. Postimpact examination of the wreckage revealed a fracture in the wing spar about 18 inches in from the right wing tip. There was a discoloration in the fracture, which had the appearance of a varnish like substance. An FAA inspector reported that 'there were different color glue joints in the wing construction indicating that there were different kinds of glue used.' Also, the failure mode differed; the dark glue joints failed in the wooden structure, where as, the other glue joints failed in the bond. Some of the wing joints that had failed had discoloration between the rib & the wooden skin. The inspector suggested that 'either improper clamping during construction, prevarnishing of the contact surfaces, or bond separation followed by moisture weathering could have caused this.' The plt had purchased the homebuilt acft on 10/1/96. It had been originally certificated for flight on 10/27/72. On 2/11/73, it had been damaged during a takeoff mishap, & 'new wing construction' had been performed.

Quoted verbatim from the NTSB record.