Beechcraft G18S N9312Y

Summary

On 6 October 1997 at about 23:30 local time, a Beechcraft G18S registered N9312Y was involved in an accident near Crosbyton, Texas, United States. One person was on board and one was seriously injured. The aircraft was substantially damaged. The NTSB has published a probable cause for this accident; it is quoted in full below.

Date

6 October 1997 at 23:30

Classification

Accident

Location

Crosbyton, Texas, United States

Coordinates

33.6410, -101.2297

Aircraft

Beechcraft G18S

Registration

N9312Y

Category

Airplane

Engines

2

Operator

Not recorded

Operating rule

Part 135: Air Taxi & Commuter

Purpose of flight

Unknown

Phase of flight

Not recorded

Route

Lubbock → Dfw Intnl.

Aircraft damage

Substantial

Weather

IMC

Light

Dusk

NTSB number

FTW98LA007

1 person was seriously injured.

Inadequate maintenance which resulted in diminished carburetor heat effectiveness due to missing alternate air doors. Contributing were conducive carburetor icing weather conditions, low ceilings during the emergency descent, and the lack of suitable terrain for the forced landing.

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

Read the full NTSB narrative

While in cruise flight at 9,000 feet MSL, the left engine began to 'run rough and lose power.' The pilot said he interpreted the problem as carburetor icing and applied carburetor heat. With the engine still running rough, the left propeller was feathered and the left engine shut down. Restart attempts were not successful. Unable to maintain altitude, the pilot requested to land at a nearby airport. After descending through IMC weather, the pilot realized that he would not make it to the airport, and executed a forced landing to rough/uneven terrain. Examination of the engines revealed that the alternate air doors were missing on the right and left engine. The hinges for the doors were attached to both carburetors and showed no evidence of distortion or impact damage. The doors were not found at the wreckage site. A missing alternate air door would allow ambient air to enter the carburetor, rendering the carburetor heating system ineffective. According to carburetor icing probability charts, the reported temperature and dew point values would be favorable to the formation of induction system icing.

Quoted verbatim from the NTSB record.