History of Flight
On February 7, 2011, at 1147 Pacific standard time, a Beech 95-B55 (T42A), registration N225DH, impacted the grounds of a recreational vehicle storage facility after performing a precautionary low pass at San Bernardino International Airport, San Bernardino, California. The pilot operated the airplane under Part 91. The private pilot and a private pilot licensed passenger sustained serious injuries. The airplane sustained substantial damage. The personal cross-country flight departed San Luis Obispo, California, at 1033, with a planned destination of San Bernardino. Visual meteorological conditions prevailed, and an IFR flight plan had been filed.
The pilot and passenger reported that due to their injuries, recollection of the accident, particularly the final stages, was unclear. Before departure, they performed an uneventful preflight inspection. The passenger noted that the main fuel tanks were full and the auxiliary tanks about half capacity. The pilot filed an IFR flight plan and departed. During the upwind leg, the landing gear warning horn sounded. After tower personnel confirmed the gear was retracted, the pilot sent a text message to his mechanic. He deduced a gear indication system fault and continued the flight, with the horn intermittently sounding, planning a precautionary low approach at the destination.
During climb, the pilot switched from main to auxiliary fuel tanks. The flight continued uneventfully until air traffic control gave a clearance direct to San Bernardino, surprising the pilot. He performed the descent checklist in a rushed manner, switching to main tanks without the customary 10-second pause between tanks. Upon arrival, he extended the landing gear, confirmed visually and by the green light, and reported his intention to the tower. Tower personnel confirmed the gear appeared extended.
The pilot then felt something was wrong; the airplane was not climbing as expected, and both engines seemed to be cycling. He struggled to maintain control, could not recall troubleshooting steps, and asked the passenger to check instruments. He began a turn to look for a landing area. At about 20-30 feet agl, he observed what appeared to be an RV park. Concerned about ground injuries, he decided to stall the airplane to minimize the accident footprint. He switched fuel selectors to off and pulled both mixture levers to idle cut-off. He could not recall turning off the magnetos. He pulled back on the elevators to attempt a stall.
An FAA and Boeing flight test crew aboard a Boeing 747-8 observed the airplane flying level about 150 feet agl over the runway with gear and flaps extended, then turning left while descending. Shortly after, the nose pitched up, followed by a roll to the right and an inverted nose-down descent. The gear and flaps remained extended, and no smoke or vapors were seen.
The airplane was equipped with a Garmin GPSMap 496. Historical data showed the flight sequence. The airplane departed San Luis Obispo climbing to about 9,400 feet msl, turned left over Santa Barbara, then descended to 5,000 feet msl over Corona. At 1138, it turned left towards San Bernardino airport. At 1143, it joined left downwind for runway 24 at about 2,400 feet msl (1,241 ft agl). It descended during downwind, groundspeed decreasing to 135 mph. It turned base and final at 1,287 msl (128 ft agl), maintaining runway heading for 40 seconds, reducing speed to 108 mph, descending to about 20 feet agl. Then it began a right turn, climbing to 163 ft agl as speed decreased to 88 mph. For the remaining 66 seconds, it made a descending 180-degree left turn at an average 84 mph.
Recorded radio transmissions revealed that on left downwind, the pilot reported gear problems and requested a low approach for a visual check. Tower cleared it and reported gear down. The pilot was cleared to land on runway 24 but then reported another problem, saying he would head straight. Tower canceled landing clearance and offered runway 6. The pilot then reported he would circle back to runway 6, and tower cleared him. Tower reported light and variable winds.
The airplane came to rest about 4,700 feet southwest of the departure end of runway 24, upright on a heading of about 310 degrees, adjacent to a collapsed steel awning. Fragments of roofing and cross members were comingled with wreckage. The airframe remained largely intact with crush damage to the cabin and nose cone. Both wings remained partially attached, the tail section was in place with intact control surfaces. Fuel staining was on the tarmac, and first responders reported a strong odor of fuel.
Personnel Information
The 39-year-old pilot held a private pilot certificate with ratings for airplane single-engine land, multiengine land, and instrument airplane. His logbook indicated about 660 total flight hours since January 2001, with 21 hours of dual multiengine instruction and a multiengine rating issued August 8, 2010. His total multiengine experience as of November 28, 2010, was 101.2 hours. He held a third-class medical certificate issued May 2007 with no limitations.
Aircraft Information
The low-wing, retractable-gear airplane was manufactured in 1969, powered by two fuel-injected, normally aspirated Continental IO-470-L engines with McCauley two-blade constant-speed propellers. It had 39-gallon main and 32-gallon auxiliary fuel tanks in each wing. The flight-hour meter indicated 3,981.2 hours total time. The last annual inspection was June 23, 2010, 51.4 hours prior to the accident. The right engine was overhauled in August 1993 (about 1,020 hours prior), and the left engine in September 1988 (about 1,280 hours prior).
Wreckage and Impact Information
Examination at the site revealed the main landing gear extended; nose gear position could not be determined due to damage. Flap actuators showed extension greater than 6 inches, corresponding to full-down flaps. Fuel system lines in the cabin were ruptured and fragmented to the wing roots. The right engine fuel selector valve handle was separated from the selector shaft; both valves appeared set to the auxiliary tank positions. The fuel quantity indicator switch was noted in the auxiliary tank position.
The airplane rested tilted about 15 degrees onto the left wing. All fuel tanks were ruptured or had damaged interconnect/supply lines. About 20 gallons of fuel was recovered from the right main tank, residual from the right auxiliary, about 5 gallons from the left main, and 2 gallons from the right auxiliary. All fuel caps were secure. Fuel was tested for water with no water observed. The right engine auxiliary fuel pump operated when powered. Both wing-mounted fuel filters and engine air intake filters were clear. Magnetos were noted in the right position. Engine controls appeared continuous except the right engine fuel metering arm had separated; fracture surfaces showed bending and granular features consistent with impact. About 25 pounds of baggage was recovered.
Tests and Research
A JPI EDM-760 Engine Monitor recorded engine parameters from start to accident. Data showed consistent operation for both engines during takeoff, climb, cruise, and descent. For the last 90 seconds, right engine exhaust gas temperature decreased from about 1,275°F to 250°F, with cylinder head temperature from 280°F to 220°F. About 10 seconds before that decrease, EGT momentarily increased by about 35°F. Left engine EGT and CHT remained constant at 1,300°F and 270°F, respectively. Battery voltage and oil temperatures for both engines remained constant.
Examination of the recovered engines at Continental Motors found no evidence of preimpact mechanical malfunction or failure.
Additional Information
The Pilot Operating Handbook (POH) for the model includes under Emergency Procedures: "ONE ENGINE INOPERATIVE GO-AROUND" with a warning that level flight might not be possible for certain combinations; do not attempt a one-engine inoperative go-around after flaps fully extended. The procedure: Power – MAXIMUM ALLOWABLE, Landing Gear – UP, Flaps – UP (0 degrees), Airspeed – MAINTAIN 100 KTS (115 mph). The pilot reported receiving training in single-engine procedures and that during those events the airplane could climb with one engine inoperative. Normal procedures require fuel selector valves set to main tanks during descent and landing.
Photographic images from the flight test crew showed the airplane just prior to impact in a 90-degree right bank, level with power transmission towers, with gear and flaps deployed and no smoke or vapors. Security camera video from the RV storage facility documented the last second, showing the airplane in a wings-level, nose-down attitude just before collision.
Fueling records from the fixed base operator at Carlsbad Airport indicated the airplane was filled to capacity with 69.9 gallons of 100LL aviation gasoline prior to the last flight on February 3, 2011, which departed Carlsbad for San Luis Obispo (duration 1 hour 35 minutes). Fuel burn for that flight was calculated at about 38 gallons; for the accident flight, about 33 gallons, based on GPS data and POH values at maximum cruise power and standard temperature.