Accident Overview
On August 17, 2019, about 1255 mountain daylight time, a Beechcraft H35 airplane, registration N5410D, was destroyed when it was involved in an accident near Ruidoso, New Mexico. The pilot and a pilot-rated passenger were seriously injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight.
Pilot Preflight Actions
The pilot reported that he had flown the airplane from Texas to the accident airport the day before without issues and was familiar with high density altitude operations. Before the accident flight, the pilot calculated a density altitude of 8,500 ft msl and an airplane weight of 2,803 pounds (about 100 pounds under gross weight, within the center of gravity envelope). He estimated a takeoff ground roll of about 2,900 ft to clear a 50-ft obstacle; the runway was 6,300 ft long. The pilot leaned the engine for maximum performance and planned to abort if takeoff speed was not reached by the 3,000-ft runway marker.
Takeoff and Loss of Power
According to the pilot, the airplane reached rotation speed about midfield and climbed to about 150 to 200 ft agl when he noticed a loss of engine power. The airplane began to descend, and he maneuvered for a forced landing.
Witness Observations
A witness located on the west side of the airport observed the airplane flying unusually low (no higher than 100 ft agl) in a northerly direction over runway 30. When it reached the intersection of runway 06/24, it descended out of view. The witness heard the engine and saw no smoke or vapors. He prepared a fire truck and drove to the accident site, where about 5 gallons of fuel had leaked from one wing that had struck a tree.
Examination Findings
The airframe was severely damaged; the engine was detached from the airframe. The left magneto was attached; the right magneto mount was partially damaged. The starter was detached; the carburetor severely damaged. All cylinders remained attached. Top spark plugs were intact with normal operational signatures and electrode gaps consistent with service specifications. The crankshaft was rotated by hand, establishing rotational continuity through the engine and valve train to the accessory section. Equal movement was observed on all intake and exhaust valve rocker arms. Thumb compression and suction were obtained on all six cylinders. Magnetos actuated by rotating the crankshaft produced spark. The intake system was severely damaged but intact at the cylinder heads. The air filter and filter housing were severely damaged; the exhaust system similarly damaged but intact at cylinder heads. Internal borescope inspection of cylinders showed normal piston tops and cylinder sidewalls, with no evidence of foreign object ingestion. The examination revealed no mechanical malfunction that would have precluded normal operation.
Onboard Video Data
An onboard GoPro camera captured two video files. The first showed the airplane taxiing: tachometer 1,300 rpm, engine total time 1,781.74 hours, fuel pressure 3 psi, manifold pressure 13 inHg, suction 4.75 inHg, altimeter about 6,750 ft msl, fuel quantity 51.6 gallons. The second video showed the takeoff: power applied, tachometer 2,600 rpm, fuel pressure 6.5 psi, manifold pressure 22.5 inHg, suction 6 inHg. About 40 seconds after acceleration started, the airplane lifted off; landing gear retracted. About 25 seconds after takeoff, intersecting runway 6/24 passed below. About 38 seconds after liftoff, tachometer 2,400 rpm, manifold pressure 23 inHg, suction 5.8 inHg, gear retracted, propeller control lever full-forward. About half a second later, throttle lever full-forward, mixture control lever appeared in line with throttle (full-forward, rich position), yoke pulled aft. The airplane impacted terrain 40 seconds after takeoff.
Weather Conditions
Based on the airport’s automated weather observation system at 1255, the density altitude at the time of the accident was about 9,700 ft msl, which required a takeoff distance of about 3,300 ft.