History of Flight
On November 4, 2009, at about 1920 eastern standard time, a Cessna 172S, registration N5194X, operated by Eagle Aircraft, was destroyed after colliding with wooded terrain and a post-crash fire following a rapid descent after takeoff from Tallahassee Regional Airport (TLH), Tallahassee, Florida. The certificated flight instructor and the certificated private pilot were fatally injured. Night visual meteorological conditions prevailed for the local instructional flight, which originated at TLH about 1915. No flight plan was filed; the flight was conducted under 14 CFR Part 91.
Radar and voice communication data from the Federal Aviation Administration (FAA) revealed that the airplane was cleared for left traffic pattern work at TLH. It departed runway 36 and climbed straight ahead to about 600 feet mean sea level (msl) before beginning a left turn to the crosswind leg. The airplane reached 1,000 feet while turning from crosswind to downwind. Over approximately 10 seconds, the last three radar targets showed the airplane at 1,000, 800, and 400 feet, respectively, in a left arc oriented toward the airport. At the start of the descent, the airplane was at 1,000 feet, three-fourths of a mile from the runway, and one-half mile from the perimeter fence.
The tower controller reported visually tracking the airplane, noting the landing light and position lights were illuminated. He perceived the descent immediately. At 19:16:39, he transmitted the registration number; at 19:16:41, the airplane responded with "N5194X" in a clipped manner. No further communications occurred. Shortly after, the controller observed a fireball in the woods west of the airport and alerted the airport fire department.
Personnel Information
The flight instructor held a commercial pilot certificate with ratings for airplane single-engine land, multiengine land, and instrument airplane, and a flight instructor certificate with a single-engine rating. His most recent FAA third-class medical certificate was issued March 2008. A recovered logbook showed 1,202 total flight hours, with 40 hours in the previous 90 days, 20 hours in the previous 30 days, and 133 total night hours. His experience in Cessna 172 airplanes could not be determined.
The private pilot held a private pilot certificate with ratings for airplane single-engine land and instrument airplane. His most recent FAA second-class medical certificate was issued June 2008, at which time he reported 600 total flight hours. His logbook was not recovered. Aircraft rental records indicated that between that medical examination and the accident, he accrued 48.2 flight hours, all in a Cessna 172. His night flying experience could not be determined or estimated.
Aircraft Information
The airplane was manufactured in 2002. Its most recent 100-hour inspection was completed on November 4, 2009, at 2,956.6 total aircraft hours. According to the Cessna 172S Information Manual, at best glide airspeed from 1,000 feet above the airport in calm winds, the airplane could travel 1.75 miles. Radar data showed that at its farthest point from the departure runway, the accident airplane was at 1,000 feet altitude, 0.75 miles from the perimeter fence, and 0.92 miles from the runway.
Meteorological Information
At 1944, the weather at TLH included clear skies, calm winds, visibility 10 miles, temperature 15°C, dew point 12°C, and an altimeter setting of 30.23 inches of mercury. At 2053, the weather included few clouds at 500 feet, visibility 8 miles in smoke, attributed to a controlled burn in the Apalachicola National Forest, which bordered the airport and extended hundreds of square miles west and south.
At the accident time, the moon was 0.9 degrees above the horizon at an azimuth of 061 degrees, 94 percent illuminated, placing it behind the airplane as it turned from upwind to crosswind.
Aerodrome Information
TLH is located about 4 miles southwest of downtown Tallahassee, Florida, with an official elevation of 81 feet. The tower-controlled airport had runways 18/36 (6,076 by 150 feet) and 9/27 (8,000 by 150 feet). The airport is bordered to the west and south by the Apalachicola National Forest, a densely wooded, unlighted area with little ambient light.
Previous NTSB findings from the investigation of Federal Express Flight 1487 at TLH noted that the approach over the forest produced conditions conducive to a "Black Hole" approach illusion, which likely contributed to that flight crew's improper approach.
Wreckage and Impact Information
All major components were accounted for at the site. The wreckage path, on flat wooded terrain, was oriented 110 degrees magnetic and about 600 feet long. Trees along the path were broken progressively lower, with scattered angular wood pieces. The cockpit, cabin, and inboard sections of both wings were consumed by fire, with no discernible instruments. Outboard wing sections and the tail section were separated by impact. Control cable continuity was established, with all failures consistent with overload.
The engine was separated from the airframe and fire-damaged. The propeller separated from the crankshaft, with fracture surfaces consistent with overload. Blade 2 displayed a slight aft bend; blade 1 showed twisting along its length and a missing tip. Examination of blade 1 revealed mechanical overstress. Paint transfers from the nose cowling were observed around the propeller spacer, and the cowling had deep scoring near the propeller opening. The engine rotated by hand, compression was confirmed, spark plugs were intact and tan/gray. Magnetos could not be tested due to fire damage. Vacuum pump rotors were free and vanes intact. A re-examination on January 14, 2010, revealed no pre-impact mechanical anomalies.
Medical and Pathological Information
Autopsies performed by the Office of the Chief Medical Examiner in Tallahassee, Florida, indicated that both pilots died from multiple blunt-force trauma. Toxicological testing by the FAA's Bioaeronautical Sciences Research Laboratory was negative for carbon monoxide, cyanide, ethanol, and drugs.
Additional Information
FAA Advisory Circular AC 60-4A on pilot spatial disorientation notes that it can take up to 35 seconds to establish full control by instruments after loss of visual reference, and that surface references can become obscured even in visibility above VFR minimums, common during night flights over sparsely populated areas. The circular also describes the graveyard spiral illusion, where a prolonged turn can lead to a sensation of turning in the opposite direction, resulting in a descending spiral if not recognized.
Textbooks on aerospace medicine note that G-induced excessive movement of the otolithic membranes can cause a pilot to feel an extra head and body tilt, interpreted as an underbank when looking up into a turn, leading to overbanking and descent. The Aeronautical Information Manual describes the somatogravic illusion, where rapid acceleration can create a nose-up illusion, and rapid deceleration the opposite. Additionally, the pilot in this flight, after initiating a turn, would have been susceptible to a G-excess illusion if looking up and inside the turn, potentially causing overbanking.