NTSB Factual Report

HISTORY OF FLIGHT

On October 29, 1996, at 1928 eastern standard time, a Cessna 172L, N7737G, was destroyed when it collided with trees while on final approach to runway 22 at Culpeper County Airport, Brandy Station, Virginia. The certificated flight instructor (CFI) and the dual student were fatally injured. Night visual meteorological conditions prevailed and a flight plan was not filed. The instructional flight was conducted under 14 CFR Part 91, and originated at Warrenton-Fauquier County Airport in Warrenton, Virginia, at 1716.

According to the Airport Manager, the instructor had planned to take the student on a night training flight for about 3 hours in preparation for his private pilot check ride. The Manager said the CFI had taken his Instrument Instructor check ride about 30 days prior to the accident, and he had flown with the CFI earlier that afternoon for about 1.7 hours on an "instructor's refresher flight." The manager said it was sunset, the sky was clear, the winds were calm, and the airplane was refueled before the night training flight. The instructor and student completed two to three touch and go landings at the Warrenton Airport, and the engine was running well. He said that he left the airport for home, about 1830.

There were no witnesses to the crash. The airplane was reported overdue by the CFI's family to the police department. Search personnel located the wreckage adjacent to the road near the airport. A watch found in the wreckage was stopped at 1928.

The airplane impacted terrain about a half mile west of the Culpeper County Airport, in a wooded area, during the hours of darkness about 38 degrees, 32 minutes north latitude, and 77 degrees, 51 minutes west longitude.

PILOT INFORMATION

The pilot-in-command held an airline transport pilot, and flight instructor's certificate. The pilot's log book was not located. According to the application for his most recent Federal Aviation Administration (FAA) First Class medical certificate dated June 25, 1996, he reported 5,400 hours of total flight time. According to a pilot information form updated on May 31, 1995, he reported over 632 hours in airplanes, including 85 hours in make and model.

The student pilot's log book revealed that he had accumulated over 37 hours of total flight experience, which included 36 hours in make and model. There was no record of any night time recorded in his log book. His most recent FAA Third Class medical certificate was dated July 31, 1996.

METEOROLOGICAL CONDTIONS

At 1845, Charlottesville-Albemarle Airport, Charlottesville, Virginia, reported the following observation:

Sky condition, clear; visibility, 20 miles; temperature, 60 degrees Fahrenheit (F); dew point, 42 degrees F; winds from 160 degrees at 5 knots; and altimeter 30.01 Inches Hg.

On the evening of October 30, 1996, at 1800, the NTSB investigator was on scene, and she observed that it was a dark, moonless night without a horizon.

WRECKAGE AND IMPACT INFORMATON

The airplane wreckage was examined at the accident site on October 30, 1996. The examination revealed that all major components of the airplane were accounted for at the scene. Initial tree impact scars were observed at the tops of 80 feet high trees, 180 feet from the Initial Impact Point (IIP) with the ground. A ground scar extended 40 feet from the IIP to the main wreckage, which came to rest inverted. The tailcone and empennage were twisted upright on an approximate magnetic heading of 010 degrees.

Initial tree impact scars started approximately 2,158 feet from the approach end of runway 22. The tree scars indicated a general direction of 207 degrees. Fragments of the left main landing gear pant leading edge, and windshield fragments, were found along the tree impact flight path.

The engine was separated from the fuselage, and was located in the vicinity of the main wreckage. It came to rest inverted, 35 feet beyond the IIP. The engine case was intact and not broken. All the accessories were attached except the vacuum pump. The cylinders were attached and secured to the crankcase. There was no evidence of uncontained internal engine components.

The nosewheel landing gear assembly was separated from the airplane, and was found next to a ground scar, about 40 feet from the IIP.

The left wing contained damage to the leading edge outboard section. The left wing was swept forward relative to the fuselage. The right wing was deformed slightly aft relative to the fuselage. The right aileron was bent upward and underneath the right wing, and the left aileron was held in a up position by cable tension.

The tip of the right stabilizer was broken and crushed aft.

Control continuity from the elevator, rudder, and ailerons was verified from all control surfaces to the cockpit controls, except the aileron cross-over cable which was broken in tension in the vicinity of the left wing root. The flap extension cable was broken in tension overload, and the flap switch was destroyed. The flap retract cable was intact, but detached from the left flap sector. The flap actuator measured 2 3/8 inches, and the elevator trim actuator measured 1.3 inches. According to the Cessna representative this corresponded to 10 degrees of flaps, and 5 degrees up elevator trim tab.

The underside of the nose section of the airplane was crushed upward. The cabin top towards the rear window was crushed downward into the cabin area. The left cabin door was crushed downward at the top, and exhibited leading edge aft compression damage in the lower section. The right seat was found outside the airplane, intact, and adjacent to the cabin. The left seat remained attached to the seat rails which were bent upward and partly detached from the floorboard.

The engine was examined in a hangar at the airport on October 31, 1996, under the supervision of the National Transportation Safety Board (NTSB) investigator.

The propeller and spinner remained attached to the engine. The spinner was crushed. One propeller blade was bent aft outboard from the hub, and contained a large gouge in the leading edge. The other blade's tip was bent aft. Both blades displayed chordwise scratches.

The spinner and propeller were removed from the engine. The top spark plugs, and all rocker box covers were also removed. The crankshaft was rotated from the vacuum pump drive. The crankshaft rotated freely, and resulted in the operation of the cylinder valves, confirmation of compression in each cylinder using thumb compression method, and magneto sparking to the left magneto. The right magneto was removed, manually rotated, and also produced spark. The oil suction screen was examined and it was found free of any metal particles.

The carburetor was disassembled, and no evidence of mechanical malfunction was revealed. There was no fuel in the bowl; however, during the recovery of the airplane from the woods, fuel was found in the left wing.

Examination of the wreckage revealed no pre-impact failure of the airplane or engine.

TESTING

The Vacuum pump was removed and sent to the NTSB Laboratory for examination. According to the NTSB National Resource Specialist report, the internal rotor and vanes were examined after removal of one end of the pump. The rotor vanes were intact and the vanes moved easily within the rotor. Examination of the side wall of the vane housing revealed minor scoring, but no damage that would prohibit proper operation of the pump.

MEDICAL AND PATHOLOGICAL INFORMATION

An autopsy and toxicological testing of both airplane occupants, was conducted by Dr. R. DeSimone, Medical Examiner of Fairfax, Virginia, 9797 Braddock Road, Suite #100, Fairfax, Virginia, 22032, (703) 764-4640.

Toxicological testing was conducted by the FAA Civil Aeromedical Institute (CAMI), in Oklahoma City, Oklahoma, on the pilot on January 23, 1997, and the student on February 18, 1997.

ADDITIONAL DATA/INFORMATION

The Visual Approach Slope Indicator (VASI), for runway 22 was inspected after the accident by Steven R. McNeely of the Department of Aviation, Commonwealth of Virginia, 5702 Gulfstream Road, Sandston, Virginia, 23150, (804) 236-3641 Ext. 132. The check revealed that the Bar VASI provided a clearance of 96.51 feet above the trees, 2,158 feet from the approach end of the runway.

The aircraft wreckage was released on November 10, 1996, to James T. Brewer, a representative of the owner's insurance company.

NTSB Probable Cause

the certificated flight instructor's failure to ensure that proper altitude/clearance was maintained above the terrain and trees, while on final approach. Darkness was a related factor.