QUANTICO, VA, USA
N669MC
Beech T-34B
The airplane departed on a local training flight. A flight instructor in the rear seat was checking out the front seat pilot who was new to the airplane. Witnesses reported that after the airplane became airborne, it did not climb as expected. While over the water and beyond the departure end of the runway, at an estimated altitude of 150 to 200 feet above the water, the airplane was observed to enter a shallow left turn. The bank increased, the nose dropped and the airplane struck the water. The CFI was found with his shoulder harness not connected. No evidence of pre-existing mechanical failure was found with the airframe or engine.
HISTORY OF FLIGHT On August 29, 1998, about 1310 eastern daylight time, a Beech T-34B, N669MC, was destroyed when it impacted water shortly after takeoff from Turner Field, Quantico Marine Corps Air Field (NYG), Quantico, Virginia. The two commercial rate, certificated flight instructors (CFI's) were fatally injured. Visual meteorological conditions prevailed for the local instructional flight. No flight plan had been filed for the flight that was conducted under 14 CFR Part 91. The purpose of the flight was to check out a new club member in the airplane. The pilot-in-command (PIC) was seated in the rear seat, and the pilot receiving instruction was seated in the front seat. The accident was witnessed by several persons in various locations. A flight instructor who had previously flown a T-34 reported: "...I observed the pilots trying to start the aircraft. It took an abnormally long time to get it started. The pilot kept cranking the engine for what must have been well over a minute before it caught...It sounded rough at first but appeared to smooth out as they taxied out...." A flight instructor in the traffic pattern reported: "...While on downwind, the T-34 back taxied for full use of runway 20. By the time we had turned final, the T-34 was at about the 1500 foot marker on their takeoff roll. During our flare to landing, I noticed that the T-34 was only 100-200 feet high at the end of runway 20. We had intended to do a touch-and-go but shortly after our landing, [we] noticed that the T-34, about a mile out, was turning back toward the field. No radio call had been made...Before we could turn off the runway, the T-34 nosed down and banked sharply to the left. It appeared to be at an altitude of about 100-150 feet. The T-34 impacted the water about 1/2 miles off shore in a left turn, left wing first, and exploded...." A witness fishing near the departure end of the runway reported: "I heard the plane taking off. The sound attracted my attention. The engine sounded unusually loud and, although it did not sound as if it were running rough, each power pulse was distinctly audible. I turned to observe a T-34 at approximately the 3/4 to 4/5 point down the runway to departure, approximately 50 to 100 feet in the air. The airplane appeared to be climbing slowly, almost as against a headwind...As the airplane reached the end of the runway, I lost sight of it...." A military pilot who was near the gym reported: "...I clearly saw two pilots, both facing forward. It appeared normal. I continued watching because I wanted to see when (or if) he was going to raise the landing gear. He started a slow left turn with the gear still down. I noted nothing abnormal in the sound of the engine and it appeared to be a normal takeoff. As he continued his left turn, it appeared to be a fairly light turn, but it didn't appear to be a very high bank. In what appeared to be a smooth - not abrupt - but rapid increase in bank and nose dip...He fell fairly rapidly nose first continuing the left turn...during the maneuver I noted no change in engine sound...." The accident occurred during the hours of daylight at 38 degrees, 29 minutes, 56 seconds north latitude, and 77 degrees, 18 minutes, 32 seconds west longitude. PERSONNEL INFORMATION The pilot-in-command (PIC) held a commercial pilot certificate with ratings for airplane single and multi-engine land, single engine sea, and instrument airplane. He also held a flight instructor certificate for single and multi-engine airplanes and instrument airplane. According to available records, he had 16,416 hours total time. His time in the T-34 was not available. The PIC had previously received a first class airman medical certificate from the Federal Aviation Administration (FAA) on September 28, 1995. It was valid, when on March 7, 1997, the pilot reported he was experiencing chest pains. He was examined and found to have coronary artery disease. On March 27, 1997, he underwent angioplasty and intracoronary stent placement, and subsequently became ineligible to hold a airman medical certificate. On November 5, 1997, he was examined, and the FAA issued him a limited third class airman medical certificate, with an expiration date of November 30, 1998. A check of payroll records for the PIC between March 7, 1997, and November 5, 1997, revealed he had been paid as a flight instructor for student instruction during this period. Examination of 14 CFR Part 61.23 revealed a pilot was required to hold at least a third class airman medical certificate if he was acting as PIC, or as a required crewmember. The pilot receiving instruction held a commercial pilot certificate with ratings for single and multi-engine land airplanes, and instrument airplane. In addition, he held a flight instructor certificate for single and multi-engine airplanes, and instrument airplane. He was last issued a first class FAA airman medical certificate on May 1, 1997. According to available records, he had 702 hours total time, with no previous time in the T-34. AIRCRAFT INFORMATION The airplane was a former U.S. Navy T-34B which was being operated by the US Marine Corps Flying Club, Quantico, Virginia. There was no civilian flight manual for the airplane. The Naval Air Training and Operating Procedures Standardization Program (NATOPS) manual for the airplane was the guiding document for flight operations. The airplane had originally been delivered with a Continental O-470-4 engine that had a pressure carburetor installed. The engine was subsequently modified by the Navy to a fuel injected configuration. The airplane was equipped with seat belts and shoulder harnesses for both occupants. Examination of the system revealed it was not possible to release the shoulder harnesses without releasing the seat belt. In addition, the shoulder harnesses were designed to lock in position with the onset of longitudinal deceleration. The airplane had been modified in accordance with supplemental type certificate (STC) SA 5549 SW, with the addition of a stall warning light on both the front and rear instrument panels. AIRDROME INFORMATION (Departure) Marine Corps Air Facility, Quantico, Virginia was a military airfield. An air traffic control tower (ATCT) was in operation during the week, and was shut down on weekends. When the ATCT was shut down, pilots used the UNICOM frequency for reporting positions and intent of operation. The departure runway was 4,236 feet long, 200 feet wide, and had an asphalt surface. WRECKAGE AND IMPACT INFORMATION The airplane sank in 10 to 12 feet of water. As it was lifted from the water, burn marks were visible on the outboard half of the left wing and left side of the aft fuselage. The landing gear was extended, and the wing flaps were retracted. The right wing was partially separated and pushed aft. The leading edge of the right wing was compressed. The trailing edge wing flap was bowed out on the top and bottom. The left wing was crushed and compressed between the pitot tube and the fuselage. The trailing edge wing flap was bowed out on the top and bottom. All flight control cables were attached, and no breaks were observed. The elevator and rudder could be actuated from either cockpit. The aileron cables were intact, but could not be actuated due to a pinched cable in the right wing root. The canopies were found in the closed position with the glass intact. The canopies were pried off to extract the occupants. The airplane was equipped with an emergency canopy opening system. Examination of the system revealed it had not been actuated, pressure was in the bottle, and after recovery of the airplane, it was actuated and worked properly. The engine mounts were broken, and compression wrinkling was visible on both sides of the forward fuselage, emanating from the leading edge of the wings and continuing upward and forward to the top, aft side of the engine. Fuel was found in the main sump, and in the pressure line to the fuel control unit. The fuel control unit was fractured between the throttle body and the lower portion of the unit. The throttle was found in the closed position. The covers over the emergency fuel system switches were found safety wired in both cockpits. The engine was transported to Mattituck Airbase, Mattituck, New York, for an engine run. It was necessary to replace some of the spark plugs to get the engine running. Once it had run, the original spark plugs were placed back in the engine and the engine ran again. A magneto check revealed a drop of 100 RPM on the left and right magnetos. MEDICAL AND PATHOLOGICAL INFORMATION The toxicological testing report from the FAA Toxicology Accident Research Laboratory, Oklahoma City, Oklahoma, was negative for drugs and alcohol for both pilots. Autopsies were conducted on both pilots, on August 30, 1998, by the Medical Examiner's Office, State of Maryland. TESTS AND RESEARCH Several bulbs including the front pilot boost pump bulb, front pilot inverter bulb, rear pilot inverter bulb, generator bulb, and take command bulb were submitted to the Safety Board Materials Laboratory for examination. According to the Materials Laboratory factual report, none were found to have filament stretch. The throttle mixture and linkage assembly were submitted to the Safety Board Materials Laboratory for examination. According to the Materials Laboratory factual report, the breaks were typical of bending overstress separations. ADDITIONAL INFORMATION The front seat pilot was found strapped in his seat with both the seat belt and shoulder harness engaged. The rear seat pilot was found strapped in his seat with the seat belt engaged, and the shoulder harness not engaged. According to the NATOPS checklist for the T-34B, "Harness - FASTENED" was found in the PRESTART CHECKLIST and, "Harness - LOCKED" was found in the TAKEOFF CHECKLIST. According to Section III, Normal Procedures in the NATOPS Manual "Upon completion of the takeoff checklist and after takeoff clearance is obtained, align the aircraft on the runway. Apply full throttle to commence the takeoff run, and at 50-55 knots place the nose slightly above the taxi attitude. Fly the aircraft smoothly off the ground. When positively airborne and a safe landing can no longer be made on the runway, raise the gear. Maintain takeoff attitude until the airspeed reaches 100 knots and establish the 100-knot normal climb." According to Section IV, Flight Characteristics in the NATOPS manual: "Stalls in this aircraft...are characterized by an exceptionally clean break and extremely rapid recovery. It is difficult to stall the aircraft accidentally, except as the result of acceleration, since the stall attitude is very steep. Very little aerodynamic warning precedes the stall and the best indications of an approaching stall condition are attitude, airspeed and rapid increase in control sloppiness. That stall itself is characterized by an immediate pitch-down. If the aircraft is allowed to yaw, a roll will develop which may continue up to 30 to 40 degrees and then stop. This roll is easily corrected with coordinated control during recovery. Position of the landing gear has little or no effect on stall characteristics." "POWER-ON STALLS As the airplane decelerates, right rudder must be added to counteract torque and maintain straight flight. Yaw present at the break of the stall will cause the aircraft to roll., This roll is most pronounced with flaps down. After the nose drops through the horizon, rudder and aileron are both effective in returning the wings to level." "STALL RECOVERY (NORMAL) "Altitude permitting, stall recovery will normally be made as follows: 1. Release back pressure on stick immediately and smoothly advance throttle. 2. Roll wings level and return to level flight. Avoid pulling back too severely, as a secondary stall or excessive g-loads may result. 3. When level flight is resumed, reduce throttle to cruising power." "STALL RECOVERY (LOW ALTITUDE) Low altitude stall recovery differs from normal recovery as follows: 1. Use power to hold the altitude loss to a minimum. The nose of the aircraft should be allowed to drop only slightly below the horizon. 2. Use coordinated aileron and rudder to roll the wings level and return to level flight as rapidly as possible. 3. When control is regained, establish climb." According to performance charts contained in section 11, at maximum gross weight, the airplane would have required a ground roll of less than 1,600 feet to become airborne, and would have cleared a 50 foot obstacle in less than 2,000 feet total distance. Additional Persons Participating In the Investigation: Alfred L. Johnson, Quantico Marine Corps Flying Club. Wreckage Release The airplane was released to the Quantico Marine Corps Flying club on September 3, 1998.
The failure of the flight instructor to maintain airspeed which resulted in an inadvertent stall/spin.
Source: NTSB Aviation Accident Database
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