SEA00LA070

The pilot, accompanied by a passenger, was conducting a low approach at full flaps (40 degrees) in the Cessna 150M to a minimum altitude of approximately five feet AGL above the runway. Following the go-around, he added full power but left the flaps fully extended. The aircraft failed to climb, and approaching high tension power lines across his flight path he made a gradual right turn, ultimately colliding with a second set of power lines perpendicular to his flight path and approximately 55 feet above ground. The Pilot's Operating Handbook (POH) for the aircraft discussed flap settings for takeoff and specifically stated 'flap deflections greater than 10 degrees are not approved for takeoff.' Additionally, the POH also discussed balked landing procedures stating 'in a balked landing (go-around) climb, the wing flap setting should be reduced to 20 degrees immediately after full power is applied. The POH balked landing checklist included a requirement to retract the flaps to '20 DEGREES.' Post-crash examination revealed that the flaps were fully extended.

On April 12, 2000, approximately 1351 Pacific daylight time, a Cessna 150M, N9301U, registered to Paholke Leasing, Inc., and being flown by an airline transport pilot, was substantially damaged during an in-flight collision with power lines while attempting to climb following a low approach at the Auburn Municipal airport, Auburn, Washington. The pilot and passenger sustained minor injuries and two occupants of a vehicle on the ground also sustained minor injuries from flying debris. Visual meteorological conditions prevailed and no flight plan had been filed. The flight, which was personal, was to have been operated under 14CFR91, and originated from Renton, Washington, approximately 1245.

The pilot provided a statement to the investigator-in-charge which contained the following (in part): "we ... headed directly to the Auburn Airport, which was using runway 34, with a light wind from the northwest. I entered a left downwind from a 45 degree angle at 1000 ft MSL. I planned a low approach to fly the airplane slightly above the runway in the landing attitude with landing flaps. When I had completed the low approach, I added full power and began to climb and accelerate to flap retraction speed. However, the acceleration was negligible and I could see that I would not be able to cross the high tension power lines north of the airport. I turned to the right, using a 5 degree to 10 degree angle of bank, to parallel the power lines and allow more room for acceleration and climb. As I approached Auburn Way on an easterly heading, the airplane seemed to be alternating between level flight and a slight descent and had still not accelerated sufficiently to begin raising the flaps. The airspeed had stagnated around 50 knots. It appeared that we might not be able to clear the power lines along Auburn Way, but could not turn due to the marginal performance of the airplane. Within a second of striking the power lines on the east side of Auburn Way, the stall warning sounded. The airplane contacted the power lines and began to pitch rapidly nose down, out of control. The aircraft struck the ground inverted." (refer to photographs 1 and 2).

Additionally, the pilot amplified his narrative with the following comments: "Throughout the low approach and climb, the flaps were full down with an indication of approximately 32 degrees..." and "the minimum altitude during the low approach was approximately five feet..." (refer to attached NTSB Form 6120.1/2 narrative statement).

The pilot reported that he was unaware of any powerplant malfunction during the accident sequence. He also reported a total of 6,397 hours of flight experience of which 39 hours were in the Cessna 150 aircraft.

The Auburn airport was equipped with a single asphalt runway (34/16) measuring 3,400 feet in length. A series of east/west multiple high tension power lines were located 1,660 feet north of the threshold of runway 16 and measured 83 feet above the elevation of the runway end. Additionally, a series of power lines running north/south and roughly parallel to the runway were located along the east side of Auburn Way and approximately 1,500 feet east of the runway centerline. These lines were estimated to be approximately 55 feet in height above the ground (refer to photograph 2).

The aircraft was equipped with electrically actuated/operated flaps which could be extended to approximately 40 degrees in the full down (landing) position. The Pilot's Operating Handbook (POH) for the aircraft discussed flap settings for takeoff and specifically stated "flap deflections greater than 10 degrees are not approved for takeoff" (refer to ATTACHMENT POH-1). Additionally, the handbook also discussed balked landing procedures stating "in a balked landing (go-around) climb, the wing flap setting should be reduced to 20 degrees immediately after full power is applied. Upon reaching a safe airspeed, the flaps should be slowly retracted to the full up position" (refer to ATTACHMENT POH-2). The POH balked landing checklist contained the following five items (in order):

(1) Throttle - FULL OPEN (2) Carburetor Heat - COLD (3) Wing Flaps - RETRACT TO 20 DEGREES (4) Airspeed - 55 KIAS (5) Wing Flaps - RETRACT (slowly)

(refer to ATTACHMENT POH-3)

An inspector from the Federal Aviation Administration's Renton Flight Standards District Office examined the aircraft shortly after the accident. He reported that he observed the flaps fully extended (refer to photograph 1) and that the carburetor heat control was midway between the "FULL ON" (hot) position and "FULL OFF" (cold) position. The propeller was observed to display extensive twisting, tip curl and chordwise scratching (refer to photograph 3). The flaps were subsequently checked and found to be operational.