Accident Summary
On July 30, 2017, about 1025 eastern daylight time, a Cessna 172S, registration N612DF, was substantially damaged when it impacted terrain shortly after takeoff from Danbury Municipal Airport (DXR), Danbury, Connecticut. The pilot died from his injuries four days after the accident, and the two passengers received serious injuries. The airplane was owned by a private company and operated by Arrow Aviation LLC as a Title 14 Code of Federal Regulations Part 91 personal flight. Visual meteorological conditions prevailed, and no flight plan was filed.
Witness Accounts
The rear-seat passenger, a certificated pilot with about 1,500 hours of flight experience, stated that when the airplane was cleared for takeoff, the pilot taxied to the runway and applied what sounded like full engine power. The rear-seat passenger could not see the instruments or flight controls. After a short ground roll, the airplane took off, but it seemed that the airplane was not gaining altitude normally. Less than one minute later, the pilot stated, "we're going in."
An air traffic controller at DXR observed the airplane lose altitude after takeoff while still over runway 26, a 4,422-foot-long runway. The controller then observed it "appearing to correct" as it assumed a more nose-up attitude, then begin a left roll, followed by a "full nose up attitude, rolling to the left," before it descended and impacted the ground.
Another witness, in a dog park near the accident site, heard a small airplane "lumbering" and sounding under-powered. He saw the airplane appear to turn sharply 180 degrees, then impact the ground.
Pilot Information
According to Federal Aviation Administration records, the pilot held a private pilot certificate with ratings for airplane single-engine land and rotorcraft-helicopter. His most recent FAA third-class medical certificate was issued June 14, 2016, at which time he reported 582 hours of total flight experience. The pilot's logbook was not recovered.
Aircraft Information
Review of the airplane's maintenance records revealed that the most recent annual inspection was completed on July 21, 2017, about 17 flight hours before the accident. At that time, the airframe had accrued about 4,013 hours and the engine had accrued 656 hours since overhaul.
According to fuel records and statements from the operator, the airplane was fueled to capacity on the afternoon of July 28. The accident flight was the first flight since that fueling. The airplane's maximum gross weight was 2,550 lbs. The airplane's estimated weight at the time of the accident, including full fuel and the three occupants (not accounting for any baggage), was about 2,609 lbs.
Weight and Performance
Review of takeoff performance data revealed that, at 2,550 lbs, a pressure altitude of 500 ft mean sea level, and a temperature of 20°C, the airplane required about 1,770 ft to clear a 50-ft obstacle. The data assumed no wind and flaps extended 10 degrees. At 1053, the reported weather at DXR included wind from 350 degrees at 9 knots, temperature 23°C, dew point 12°C. According to the Pilot's Handbook of Aeronautical Knowledge (FAA-H-8083-25B) Chapter 10, Weight and Balance, excessive weight reduces flight performance in almost every respect, including higher takeoff speed, longer takeoff run, reduced rate and angle of climb, and higher stalling speed.
Examination
An initial examination by a Federal Aviation Administration inspector revealed that the fuselage came to rest upright in a nose-down attitude in an area of heavy brush about 1,000 ft from the departure end of the runway. The left wing was partially separated from the fuselage and exhibited leading edge crush damage from the root to the tip. The outboard one-third of the right wing was bent upward and aft. The fuselage was buckled on both sides aft of the rear window, and the left rear pillar was crushed and separated from the roof. The nose section, including the engine, was crushed and displaced upward and aft. The empennage, vertical and horizontal stabilizers, rudder, and elevators were largely undamaged. The ignition key was found positioned to the left magneto; however, the preimpact position of the key could not be determined.
Several branches were found severed at a 45-degree angle in the westerly path leading up to the airplane consistent with propeller contact. Both propeller blades exhibited leading edge gouges and chordwise scratches. Fuel samples from both tanks were blue in color and absent of water. Oil was present in the engine, but the quantity could not be determined due to the resting position.
The wreckage was transported to a recovery facility and examined again. Flight control continuity was confirmed from all control surfaces to the cockpit area. Measurement of the elevator trim jackscrew corresponded to a 5-degree tab up (nose down) elevator trim. Measurement of the flap actuator revealed that the flaps were in the fully retracted position.
The engine crankshaft was rotated and continuity was observed. Cylinders examined with a borescope showed no anomalies. The fuel servo, engine-driven fuel pump, flow divider, and injector nozzles were examined; no damage or debris was noted. Magnetos produced spark from all electrode towers when rotated. A GPS data card and three personal electronic devices were sent to the NTSB Vehicle Recorder Laboratory, but no performance data were recovered for the accident takeoff.