Hughes 269C N7404F

Summary

On 20 June 1994 at about 23:30 local time, a Hughes 269C registered N7404F, operated by U. S. Dept. of Agriculture, was involved in an accident near London, Texas, United States. 2 people were on board and 2 had minor injuries. The aircraft was destroyed. The NTSB has published a probable cause for this accident; it is quoted in full below.

Date

20 June 1994 at 23:30

Classification

Accident

Location

London, Texas, United States

Coordinates

30.6693, -99.5690

Aircraft

Hughes 269C

Registration

N7404F

Category

Helicopter

Engines

1

Operator

U. S. Dept. of Agriculture

Operating rule

Part 91: General Aviation

Purpose of flight

Public Use

Phase of flight

Not recorded

Route

Junction → Unknown

Aircraft damage

Destroyed

Weather

VMC

Light

Day

NTSB number

FTW94GA204

2 people had minor injuries.

THE PARTIAL POWER LOSS DUE TO A STICKING VALVE. FACTORS WERE THE REMAINING WORN LOBES ON THE CAMSHAFT AND THE LACK OF SUITABLE TERRAIN ONTO WHICH A SUCCESSFUL FORCED LANDING COULD BE EXECUTED.

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

Read the full NTSB narrative

DURING A COYOTE ERADICATION FLIGHT, THE AIRCRAFT EXPERIENCED A PARTIAL POWER LOSS. THE PILOT STATED THAT WHILE HE WAS MANEUVERING AT LOW ALTITUDE AND AIRSPEED, HE FELT A VIBRATION THROUGH THE AIRFRAME, THE ENGINE AND MAIN ROTOR RPM BEGAN TO DECREASE, AND THE NEEDLES SPLIT. HE APPLIED FULL POWER, BUT THE ENGINE WOULD ONLY DEVELOP 2,000 RPM. WHILE THE PILOT WAS MANEUVERING TO A CLEAR AREA, THE MAIN ROTOR BLADES STRUCK TREES AND THE AIRCRAFT ROLLED TO THE RIGHT AND IMPACTED THE GROUND. FOLLOWING THE ACCIDENT, THE ENGINE WAS TEST RUN IN THE AIRFRAME AND FOUND TO BE RUNNING ROUGH. INVESTIGATION REVEALED THAT THE ENGINE CAMSHAFT LOBES WERE WORN BEYOND LIMITS AND THE #4 EXHAUST VALVE WAS HEAT DISCOLORED AND SHOWED SIGNS OF STICKING.

Quoted verbatim from the NTSB record.