Executive Fliteways

After about a 20 minute flight, while on final approach for landing, the airplane experienced a loss of engine power on both engines, and the pilot-in-command (PIC) performed a forced landing into trees about 1/2 mile from the airport. The left and right boost pumps and the left and right transfer pumps, were observed in the "OFF" position. According to the PIC, after he exited the airplane, he returned to the cockpit and "shut off the fuel panel. The fuel quantity indicator toggle switch was observed in the "TOTAL" position. Examination of the fuel system revealed both engine nacelle tanks, both wing center section tanks, and the right wing fuel tanks were not compromised. About 1 quart of fuel was drained from the left and right engine nacelle tanks, respectively. Less than a quart of fuel was drained from the right wing tanks. The left wing tanks were compromised during the accident; however there was and no evidence of a fuel spill. Examination of the left and right wing center tanks revealed approximately 27 gallons (approximately 181 lbs) of fuel present in each tank. Battery power was connected to the airplane, and when the fuel transfer pump switches were turned to the "ON" position, fuel was observed being pumped from the left and right wing center tanks to their respective nacelle tanks. The accident flight was the third flight of the day for the flight crew and airplane. According to a flight log located in the cockpit, the flight crew indicated 750 lbs of fuel remained at the time of the takeoff. According to the airplane flight manual (AFM),"Fuel for each engine is supplied from a nacelle tank and four interconnected wing tanks...The outboard wing tanks supply the center section wing tank by gravity flow. The nacelle tank draws its fuel supply from the center section tank. Since the center section tank is lower than the other wing tanks and the nacelle tank, the fuel is transferred to the nacelle tank by the fuel transfer pump in the low spot of the center section tank...." Additionally, with the transfer pumps inoperative, all wing fuel except 28 gallons from each wing will transfer to the nacelle tank through gravity feed.

During climb after takeoff, left engine seized. Pilot said he attempted left engine restart; propeller would not rotate or feather. No emergency declared. Pilot stated engine shutdown procedure was used, scientific bus switches were shut off, right generator was recycled and appeared to operate normally. Pilots got immediate vector to return to Martin Airport, but radar contact was lost for about 5 minutes. Electrical problems were encountered and pilots had problems maintaining headings, thus were delayed in diverting to alternate. With left prop unfeathered, they could not maintain altitude. Due to bad weather at Martin, they diverted to Baltimore. Radar and radio contacts were lost and they could not reach Baltimore. During forced landing, aircraft hit tree and crashed short of intended landing area. Teardown of left engine revealed #4 and #5 connecting rods had failed at crankshaft; they were discolored from heat and scored; other rod bearings had indications of oil starvation. Metallic debris from failed engine found in oil system. Several oil feed holes to rod bearings were obstructed with metallic debris. Fire damaged most of the electrical system. Aircraft (modified for environmental testing) not flight tested for drag inducing modifications; written flight crew instructions not avail for modifications. A pilot was killed and three other occupants were injured.