Cessna T210N N6993N

Summary

On 28 August 2000 at about 16:50 local time, a Cessna T210N registered N6993N was involved in an accident near Council, Idaho, United States. 6 people were on board and 3 had minor injuries. The aircraft was substantially damaged. The NTSB has published a probable cause for this accident; it is quoted in full below.

Date

28 August 2000 at 16:50

Classification

Accident

Location

Council, Idaho, United States

Coordinates

44.8891, -116.5395

Aircraft

Cessna T210N

Registration

N6993N

Category

Airplane

Engines

1

Operator

Not recorded

Operating rule

Part 135: Air Taxi & Commuter

Purpose of flight

Unknown

Phase of flight

Not recorded

Route

Slate Creek → Boise

Aircraft damage

Substantial

Weather

VMC

Light

Day

NTSB number

SEA00LA173

3 people had minor injuries.

the fatigue failure of the crankshaft due to improper overhaul procedures. Factors include a soft area in the field where the forced landing took place.

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

Read the full NTSB narrative

While in cruise flight, the turbocharged aircraft's manifold pressure began to drop. Although the engine continued to run smoothly, the pilot elected to divert to an alternate airport in order to check things out. When the aircraft was about four miles from the alternate airport, the engine began to run rough, and ultimately ceased producing power. Although the pilot was able to touch down in an open field short of the airport, during the landing roll, the nose wheel encountered an area that had been softened by irrigation, and the aircraft nosed over. During the investigation it was determined that the crankshaft failed due to fatigue crack initiation in the number two main journal cheek. Further inspection revealed that a sealant had been applied to the mating faces of the main bearing saddles the last time the engine was overhauled. Application of this sealant, which is not called for in the engine overhaul manual, lead to a loss of proper crankcase clamping pressure in the area of the main bearing saddle through-bolts. Loss of this pressure resulted in bearing shift and scoring of the crankshaft journal.

Quoted verbatim from the NTSB record.