Illinois

The flightcrew of a Gulfstream G-IV began taking off on Runway 34 with a crosswind from 280° at 24 knots. About 1,340 feet after the takeoff roll began, the airplane veered left 5.14° to a heading of 335°. It departed the runway, and tire marks indicated no braking action was applied. One of the pilots said, "Reverse," then one said, "No, no, no, go, go, go, go, go." The airplane traversed a shallow ditch that paralleled the runway, which resulted in separation of both main landing gear, the left and right flaps, and a piece of left aileron control cable from the airplane. The airplane became airborne after it encountered a small berm at the departure end of the runway. Reportedly, the left wing fuel tank exploded. The main wreckage was located about 6,650 feet from the start of the takeoff roll. Examination of the airplane indicated no preexisting anomalies of the engines, flight controls, or aircraft systems. The Nose Wheel Steering Select Control Switch was found in the "Handwheel Only" position, and not in the "Normal" position. The pilot-in-command (PIC) routinely flew with the switch in the "Normal" position. The PIC and copilot (pilot-not-flying) comprised a mix crew in accordance with an Interchange Agreement between two companies which operated G-IV's. The companies' operation manuals and the Interchange Agreement did not address mixed crews, procedural differences, or aircraft difference training.

During flight, the airplane was cruising at flight level 210 in IFR conditions with turbulence and with the wind from about 255 degrees at 70 knots. The airplane drifted off course at about 1600 cst. At 1610:09, after about ten minutes of unrecognized heading changes, the pilot stated '. . . I've lost my gyro.' At 1610:15, the controller issued a no-gyro vector. At 1611:29, as the airplane was still turning (to a heading that would intercept the original course), the pilot stated 'we've lost aLL our instruments . . . please direct me towards VFR.' He was cleared to descend to 14,000 feet. At about that same time, he stated 'we're in trouble' and 'we've lost all vacuum,' then there was no further radio transmission from the airplane. The airplane entered a steep, downward spiraling, right turn. The left outer wing panel separated up and aft (in flight) from overload and impacted the left stabilizer. The airplane crashed, and parts that separated from the airplane were found over a four mile area. Investigation revealed evidence that the HSI heading card can fail without the HDG flag appearing. Although the pilot had reported the loss of instruments and vacuum, examination of the airplane revealed that the engine, flight controls, electrical system, pitot/static system and vacuum systems exhibited continuity. No malfunction was found that would have led to loss of pressurization or hypoxia.

This was the first flight of the Grumman G-21 in two years. Also, the pilot had not flown the G-21 for two years. Before taking off, the pilot reported that three takeoffs and landings would be needed for purposes of becoming current. After takeoff, he flew the airplane approximately one hour and made two full stop landings. During the third takeoff, the airplane was described as lifting off in a short distance and going into a nose high attitude below an altitude of 100 feet. The airplane then rolled left, struck the ground in a steep descent, and burned. Witnesses reported that the engines were providing power until impact; the engines and propellers had evidence of rotational damage. The flap actuators were found extended to a position that equated with 30° of flaps (half flaps). Four G-21 pilots were interviewed. According to them, flaps were not normally used for takeoff in this airplane. They reported that the turboprop engines had substantial power for the weight of the airplane, especially when the plane was not loaded, and that the G-21 would tend to become airborne quickly with flaps extended. No pre impact mechanical problem was noted during the investigation.

The pilot was cleared for the localizer runway 11 approach. The airplane impacted in an open field approximately 1 mile northeast of the airport and approximately 600 feet left of the extended centerline of the departure end of the runway. A witness saw the airplane at a low altitude, and stated 'it was foggy,' and he did not see the airplane until it was directly over his head. The witness stated that he saw the airplane for about '3 seconds,' at an altitude of 'between 50 and 100 feet above the ground,' and it did not sound like it was having 'mechanical difficulty.' The airplane turned left (north), and struck the ground with the left wing. The published missed approach called for a climbing 'right turn.' The olney airport automated weather observing system (awos) was operating and current at the time of the accident, but could only be obtained by telephone; hence atc could not provide the pilot with the current awos information. The pilot was provided the Evansville, Indiana (EVV) weather; 1,200 scattered, measured 4,500 overcast, visibility 5 miles, light rain and fog. Evansville was located approximately 20 miles southeast of Olney. The local (awos) weather was; partial obscuration, 100 feet overcast, visibility 3/4 mile.

Witnesses stated that the airplane was on final approach to runway 03 with the landing gear and flaps extended. One witness reported that when the airplane was about 50 to 100 feet above the ground, he heard the engine go to full power, and the airplane entered a steep climbing right turn. The witness stated that the airplane looked very slow during the steep climb. While in the climb, the airplane's wings leveled and then the airplane banked left and nosed down into the ground. A no-radio gyrocopter had just taken off on runway 03. Both occupants were killed.

The corporate jet's sink rate increased during short final approach. The copilot applied elevator back pressure and nose up trim. The sink rate continued to increase. The captain observed the copilot's efforts and began applying back pressure on his control yoke. Through combined efforts of both pilots they were able to increase the pitch enough that the airplane touched down on the main gear first. However, the touchdown was hard. The on-scene investigation revealed that a trip manifest container was lodged between the copilot's control yoke column and seat frame. The pilots stated the container is required to be carried in the cockpit during lights. Both pilots said there is no designated space in the cockpit to retain the container.

After takeoff, the airplane was seen at low altitude trailing smoke from the left engine. Witnesses saw the wings 'tipping' back and forth, then a wing dropped and hit the ground. Examination revealed that a supercharger bearing had failed in the left engine. The left engine had been recently installed by non-certificated personnel after being inactive for 18 years without preservation. The airplane had flown about 184 hours since the last annual inspection; no record of subsequent 100-hr inspection. The left prop blades were found in an intermediate position between the operating range and the feathered position. The left prop was changed several weeks prior to the accident. There is no evidence that the left prop had ever been successfully cycled to the full feather position. The operator and pilots were not aware of hamilton standard SB 657 recommending full-feather checks every 30 days. Left prop feathering motor relays not recovered. All 11 parachutists were found in center part of fuselage; no evidence of restraint usage. All 12 occupants were killed.