NTSB Factual Report

On September 2, 2017, about 1810 eastern daylight time, a Piper PA-28-181, N132AV, was substantially damaged during collision with terrain during takeoff from Caledonia County Airport (CDA), Lyndonville, Vermont. The private pilot and two passengers were not injured. Visual meteorological conditions prevailed, and no flight plan was filed for the local personal flight which was conducted under the provisions of 14 Code of Federal Regulations Part 91.

In a written statement, the pilot said he performed a preflight inspection of the airplane in front of the five passengers he intended to fly that day with no anomalies noted. He demonstrated the corresponding movements between the flight controls, and the flight-control surfaces; highlighting the corresponding movement between the ailerons and the control yoke.

The pilot said he then completed a 20-minute flight with two of the passengers and returned to CDA. There, a friend volunteered to fly the fifth passenger in his airplane while the pilot flew with the third and fourth passenger. The pilot cautioned his friend about the density altitude, and how his airplane "needed more time to build speed" during the takeoff roll.

After taxi, the pilot positioned the airplane on the runway for departure and performed a flight control deflection check. He said there was corresponding movement with the flight control surfaces, but that the resistance in the controls was light. His concern led him to perform the check 8 times, before he initiated the takeoff.

The pilot stated that after rotation, the airplane was unresponsive, or slow to respond, in the roll axis when he applied aileron corrections. He elected to close the throttle, and perform a forced landing to the grass area beyond the departure end of the runway. The landing resulted in substantial damage to the wings, cabin, empennage, and the tail section of the airplane.

The pilot held a private pilot certificate with a rating for airplane single-engine land. The pilot reported 310 total hours of flight experience, of which 305 hours were in the accident airplane make and model.

According to Federal Aviation Administration (FAA) records, the airplane was manufactured in 1984 and had accrued approximately 4,287.8 total aircraft hours. Its most recent annual inspection was completed June 8, 2017. The maximum allowable gross weight of the airplane was 2,550 pounds. The airplane's estimated weight during the accident takeoff was 2,428 pounds.

At 1855, the weather recorded at CDA included clear skies and calm wind. The temperature was 18°C, and the dew point was 6°C. The altimeter setting was 30.19 inches of mercury. The calculated density altitude was 1,525 feet.

The wreckage was examined at the accident site by an FAA inspector and a Vermont Agency of Transportation operations manager, and all major components were accounted for at the scene. The airplane came to rest upright about 700 ft beyond the departure end of runway 20, and about 250 ft left of the runway centerline.

Flight control continuity was established from the individual flight controls to all flight control surfaces, except for the left aileron. The aileron was significantly impact damaged, and its control rod was fractured. The corresponding fractured control-rod piece inside the wing was observed to move with control yoke inputs.

Each half of the fractured control rod was harvested from the wreckage and retained for further examination at the NTSB Materials Laboratory. According to an NTSB senior materials engineer, examination of the fracture surfaces of the control rod revealed, "All fracture features were consistent with ductile overstress fracture under bending loads. No

evidence of a preexisting crack was observed."

According to FAA Pamphlet FAA-P-8740-2, Density Altitude:

Whether due to high altitude, high temperature, or both, reduced air density (reported in terms of density altitude) adversely affects aerodynamic performance and decreases the engine's horsepower output. Takeoff distance, power available (in normally aspirated engines), and climb rate are all adversely affected. Landing distance is affected as well; although the indicated airspeed (IAS) remains the same, the true airspeed (TAS) increases. From the pilot's point of view, therefore, an increase in density altitude results in the following:

• Increased takeoff distance.

• Reduced rate of climb.

• Increased TAS (but same IAS) on approach and landing.

• Increased landing roll distance.

Because high density altitude has particular implications for takeoff/climb performance and landing distance, pilots must be sure to determine the reported density altitude and check the appropriate aircraft performance charts carefully during preflight preparation. A pilot's first reference for aircraft performance information should be the operational data section of the aircraft owner's manual or the Pilot's Operating Handbook developed by the aircraft manufacturer. In the example given in the previous text, the pilot may be operating from an airport at 500 MSL, but he or she must calculate performance as if the airport were located at 5,000 feet. A pilot who is complacent or careless in using the charts may find that density altitude effects create an unexpected –and unwelcome – element of suspense during takeoff and climb or during landing.

According to FAA Advisory Circular AC-61-23C, Pilot's Handbook of Aeronautical Knowledge:

"The effect of torque increases in direct proportion to engine power, airspeed, and airplane attitude. If the power setting is high, the airspeed slow, and the angle of attack high, the effect of torque is greater. During takeoffs and climbs, when the effect of torque is most pronounced, the pilot must apply sufficient right rudder pressure to counteract the left-turning tendency and maintain a straight takeoff path."

According to FAA Airplane Flying Handbook (FAA-H-8083-38) Chapter 4:

"…as airspeed decreases, control effectiveness decreases… because of less airflow over the control surfaces. As airspeed is further reduced, the control effectiveness is further reduced and the reduced airflow over the control surfaces results in larger control movements being required to create the same response. Pilots sometimes refer to the feel of this reduced effectiveness as "sloppy" or "mushy" controls... The pilot will notice the airplane's reaction time to control movement increases. Just before the stall occurs, buffeting, uncommanded rolling, or vibrations may begin to occur."

NTSB Probable Cause

The pilot's loss of airplane control during takeoff.