Saab-Scania Ab (Saab) 340B N396AE

Summary

On 22 February 1998 at about 16:21 local time, a Saab-Scania Ab (Saab) 340B registered N396AE, operated by Simmons Airlines, was involved in an incident near Lawton, Oklahoma, United States. 6 people were on board and nobody was injured. The aircraft was slightly damaged. The NTSB has published a probable cause for this accident; it is quoted in full below.

Date

22 February 1998 at 16:21

Classification

Incident

Location

Lawton, Oklahoma, United States

Nearest airport

Lawton-Fort Sill Regional (LAW)

Coordinates

34.5590, -98.2901

Aircraft

Saab-Scania Ab (Saab) 340B

Registration

N396AE

Category

Airplane

Engines

2

Operator

Simmons Airlines

Operating rule

Part 121: Air Carrier

Purpose of flight

Unknown

Phase of flight

Not recorded

Route

Dfw Airport → Unknown

Aircraft damage

Minor

Weather

VMC

Light

Day

NTSB number

FTW98IA130

Nobody was injured.

the collapse of the left main landing gear during landing roll as result of a shorted weight-on-wheels relay. Contributing factors were the insufficient information available to the flight crew in the company's quick reference handbook (QRH), and the manufacturer's inadequate protection of the weight-on-wheels relay from moisture.

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

Read the full NTSB narrative

During cruise flight, the flight crew reported smelling an odor similar to burning/smoldering electrical equipment and noticed that the landing gear control circuit breaker had popped. The flight crew consulted the company's Quick Reference Handbook (QRH). The QRH addressed hydraulic problems and failed to discuss possible electrical problems related to the operation of the landing gear. The company's maintenance facility was appraised of the situation; however, the maintenance person on duty was not able to assist the flight crew. Three tower fly-bys were made. The flight attendant and tower personnel reported that the landing gear appeared to be down and the gear doors were closed. The flight crew elected to land with the light on the gear handle indicating an 'in-transit' condition and the two main landing gear indicators in the 'unsafe' condition. The left main landing gear on the twin-engine transport category airplane collapsed during the landing roll. Examination revealed that the weight-on-wheels relay, which is located in the avionics bay directly under the captain's station, shorted, and as a result, the landing gear control circuit breaker popped. The electrical short was attributed to the spill of a soda can on the flight deck on a previous flight. The investigation revealed that the cockpit floor was not carpeted or sealed to prevent fluids/moisture from seeping into the electrical compartment beneath the cockpit floor. A review of the emergency extension system for the airplane revealed that the landing gear could have been extended if the fight crew had pulled the emergency extension handle.

Quoted verbatim from the NTSB record.