DFW07CA129

NTSB accident investigation · Grumman G-164A · Sayre, OK · June 6, 2007

Accident · No injuriesData collectionFinal report
Date
June 6, 2007, 12:00 local (17:00 UTC)
Place
Sayre, OK
Injuries
1 uninjured
Damage
Substantial damage
Phase of flight
Initial climb
Aircraft
N4673Grumman G-164A
Weather
Visual (VMC) · Day
Status
Completed · report July 25, 2007
Report
Approved by Office Director
Parties
Oklahoma City, Oklahoma
Case key
65938

From the NTSB’s public API. By law, NTSB reports can’t be used as evidence in lawsuits over the accident.

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Probable cause

The partial loss of engine power on takeoff-initial climb for an undetermined reason. A factor associated with the accident was the lack of suitable terrain for a forced landing.

Sequence of events

NTSB’s coding before 2008: each occurrence and phase of flight, and the causes and factors under it. The codes are defined in NTSB’s coding manual.

Loss of engine powerTakeoff - initial climb
Reason for occurrence undeterminedCause
Forced landingEmergency landing after takeoff
In flight collision with objectEmergency landing after takeoff
Object - tree(s)
Nose overLanding
Terrain condition - none suitableFactor

Analysis

The airline transport pilot departed in a single-engine, low-wing airplane for the purpose of aerial application. He reported that during takeoff, at approximately 100 feet above ground level (AGL), the engine lost partial power. He was unable to maintain altitude, and made a controlled descent into small trees off the end of the runway and then nosed over. An FAA inspector examined the airplane, and reported there was sufficient fuel on board for the flight and both water accumulators were empty. The airplane's last annual inspection was on March 21, 2007. At the time of inspection, the airplane had a total of 7,392 hours. The engine had 7,500 total hours, and 100 hours since it was last inspected. The cause for the partial loss of engine power was not determined.

Factual narrative

The radial engine lost power during a full-lenght takeoff from the 5,017-foot long concrete runway. The 9,957-hour airline transport pilot was scheduled to perform a local aerial application flight. The pilot reported that the tailwheel-equipped airplane became airborne about the midfield point of the runway. As the airplane neared the departure end of the runway, while at an altitude of 100 feet agl, "engine roughness began" and the airplane was unable to maintain altitude. The pilot held the best climb airspeed and elected to make a controlled descent into small trees located off the departure end of the runway. The airplane nosed over, and came to rest in the inverted position. There was no fire. An FAA inspector examined the airplane and reported there was sufficient fuel on board for the flight and both water accumulators were empty. The airplane's last annual inspection was performed on March 21, 2007. At the time of inspection, the airplane had accrued a total of 7,392 hours. The 450-horsepower radial engine had accumulated 7,500 total hours and 100 hours since it was last inspected. The pilot calculated that weight of the airplane during takeoff was 4,330 pounds, 169 pounds below takeoff gross weight. He also calculated that the density altitude at the time of the mishap was 4,400 feet. The reason for the partial loss of engine power could not be determined.

Aircraft

Registration
N4673
Reported as
Grumman G-164A
Category
Airplane
Serial number
1080
Airframe hours
7,392
Engine
Pratt & Whitney R-985, reciprocating
Damage
Substantial damage
Flight
Aerial application · Part 137
Registered owner
Lynn A. Flaten
Airworthiness certificate
Special, Restricted (Special)
Last inspection
Annual · March 1, 2007
Departed
304 · Sayre, OK
Destination
304
Airport
3O4 · Sayre Municipal Airport, runway 017, 5,017 × 130 ft, concrete

Matched to the registry by N-number and the event date; the registry’s history has gaps, so older matches can be wrong. Compare the reported make and model.

Flight crew

As NTSB recorded them. NTSB leaves out names.

Role
Pilot
Age
49
Injuries
None
Certificate
Airline transport
Airplane ratings
Single-engine land, Multi-engine land
Instrument ratings
Airplane
Medical
Class 1, With waivers/limitations
Seat
Single
Flight hours
9,957 total · 150 in this make and model

Weather

Conditions
Visual (VMC) · Day
Wind
225° at 5 knots
Visibility
10 statute miles
Lowest ceiling
None
Temperature
90 °F