De Havilland DHC-2 MK I N9558Q

Summary

On 17 May 2008 at about 23:45 local time, a De Havilland DHC-2 MK I registered N9558Q, operated by Lake Chelan Air Service, Inc., was involved in an accident near Stehekin, Washington, United States. 5 people were on board and 2 died, 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

17 May 2008 at 23:45

Classification

Accident

Location

Stehekin, Washington, United States

Coordinates

48.3058, -120.6603

Aircraft

De Havilland DHC-2 MK I

Registration

N9558Q

Category

Airplane

Engines

1

Operator

Lake Chelan Air Service, Inc.

Operating rule

Part 135: Air Taxi & Commuter

Phase of flight

Not recorded

Route

Chelan → Stehekin

Aircraft damage

Substantial

Weather

VMC

Light

Day

NTSB number

LAX08FA144

2 people died.

The pilot's failure to retract the landing gear wheels prior to performing a water landing. Contributing to the accident were the pilot's disabling of the landing gear warning/advisory system and possible fatigue due to his work schedule.

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

Read the full NTSB narrative

The amphibious-float-equipped airplane departed from a paved runway for the 40-nautical-mile flight to its destination, where a water landing on a lake was to be made. The pilot did not raise the landing gear after takeoff. During the flight, the air was bumpy and turbulent, and this resulted in the gear advisory system activating numerous times. The purpose of the system is to alert the pilot of the landing gear position--up for a water landing or down for a runway landing--when the airspeed decreased below a set threshold value. The pilot disabled the system by pulling its circuit breaker because the alerts were becoming a nuisance; he intended to reset the breaker during descent, but did not do so. Upon reaching the destination, the pilot set up a 150- to 200-feet-per-minute rate of descent for a glassy water landing on the lake. With the landing gear in the down position, the airplane contacted the water and abruptly nosed over. The airplane came to rest floating inverted, suspended by the floats. The pilot reported that the day of the accident was his nineteenth consecutive duty day, including office duty and flight duty. He stated that he feels the lack of days off during the previous 19 days was a contributing factor to this accident. When asked what would have prevented the accident, the pilot suggessted consistency in using the checklist. On two flights earlier in the day he had used a written checklist; on the accident flight he did not.

Quoted verbatim from the NTSB record.