California

The aircraft was engaged in a fire fighting mission in the region of Weott, California. While returning to his base at Rohnerville to pick up another load of retardant, the pilot was able to send a brief mayday message when the aircraft crashed. The pilot, sole on board was killed.

At approximately 0600, the aircraft departed Guerrero Negro, Mexico on an air taxi flight to Tijuana, Mexico. At 0715, the Tijuana weather was reported as partially obscured, visibility 1 mile with fog, haze and smoke, wind calm. During arrival, the pilot was cleared for an ILS runway 09 approach and reported over the final approach fix. However, the aircraft crashed at about 0759, before reaching the middle marker, which was 1/2 mile from the approach end of runway 09. Impact was on a ridge about 110 feet below the airport elevation and approximately 100 yards north of the international border. The aircraft was found a short time later by US Border patrol personnel. No preimpact part failure or malfunction was found. The 0800 weather at Tijuana was in part: sky partially obscured, visibility 1/10 mile with fog and haze, wind 210° at 4 knots. About 1 mile north at Brown Field, the weather was in part: sky partially obscured, visibility 3/4 mile with fog and haze, wind 280° at 4 knots. A toxicology check of the pilot's blood showed an alcohol level of 0.7‰. Calculations showed the sun would have been 16 ° above the horizon on a magnetic azimuth of 89.8°. All six occupants were killed.

The Fairchild C-119G airtanker had been dispatched to a fire about six miles west of Castle Crags State Park, California at 17:05 and departed the Siskiyou County Airport, CA (SIY) shortly thereafter. N48076, another airtanker of the same kind, a leadplane, and an air attack arrived at the fire at the same time. Two more airtankers followed shortly thereafter. The leadplane identified the target, the approach and departure routes, indicated the target was at an elevation of 4,500 feet, that the ridge on final approach was to be crossed at 6,600 feet, advised there was no wind, there was good visibility, and that there was no turbulence except a "1.5g bump" going across the head of the fire. The leadplane directed one of the C-119 airtankers to drop first. That airtanker aborted their first run because of excess speed. On the second pass, it crossed the ridge at a different point, permitting a somewhat longer final approach. That drop was a successful one. The run was made through a saddle then down a creek to the fire some two miles down stream with a planned exit down stream into a larger canyon. The leadplane then directed the mishap C-119G airtanker to drop next. The mishap airtanker used the same approach as the first airtanker. The mishap airtanker reached the uphill side of the fire when the crew reported trouble maintaining proper speed and dropped their retardant on the fire. At about the time the pilot dropped the retardant, a structural failure occurred and the right wing separated from the airframe along with the tip of the left wing and the tail booms. The fuselage with both engines and most of the left wing attached encountered terrain impact and burned as a unit.
Source: https://www.fs.usda.gov/managing-land/fire

The airplane was refueled before it departed on the accident flight; the pilot did not supervise the fueling. Shortly after takeoff, the pilot advised the Ontario departure controller that both engines were experiencing a power loss and that he suspected jet fuel contamination. The airplane collided with a berm during the ensuing forced landing. The investigation revealed that the FBO fueled the airplane with 131.3 gallons of Jet A fuel. Investigators did not locate any witnesses who saw the pilot preflight the airplane. The pilot sustained severe head injuries and could not recall if he had preflighted the airplane - the right front seat passenger was not present when the pilot boarded the aircraft.

While on an instrument flight plan in IMC, the flight was cleared for an instrument approach to the South Lake Tahoe Airport, the intended destination. The aircraft departed the initial approach fix on the published transition to the final approach course. Radar contact was lost at 11,400 feet. Afterward, the aircraft was observed descending out of clouds and maneuvering erratically in VMC until it impacted terrain with no apparent attempt to recover. Medical records revealed pilot had a history of hypertension, hyperlipidemia, and recent loss of 41 pounds on a rigid weight loss program. The autopsy revealed severe arteriosclerosis. Medical records indicated the pilot had been taking diazide intermittently for several years. Post-accident tox results were negative. The circumstances of the accident, in combination with the pilot's severe diet, medical history, and postmortem examination results support the conclusion that the pilot became incapacitated in flight. All four occupants were killed.

The aircraft had not been flown for several years and was on a flight to ferry it to another location. While cruising at 7,500 feet, the pilot decided to start using auxiliary fuel. Shortly after moving the fuel selectors to the auxiliary position, both engines lost power and would not restart. The pilot landed on a road, but the wings struck posts/mailboxes and then the aircraft hit a dirt bank. Fuel samples were taken and a visual examination revealed obvious contamination and discoloration. The aircraft had been given an annual inspection just before the flight. Both occupants escaped uninjured.

The pilot and his wife planned a 30 minutes pleasure flight to Lake Tahoe. Prior to departure the pilot failed to visually inspect the amount of fuel in the right wing tank. The tank was full. The tank's cap probably appeared to be secured when, in fact, because of a unique design characteristic, it was merely resting on top of the filler neck. Upon takeoff rotation the cap came off the filler neck and it was followed by a fuel spray. The pilot responded and stayed in a very low altitude and close-in traffic pattern. He attempted to land immediately. He lost control during the turn to final, stalled and collided with the pavement prior to reaching the threshold. Both occupants were killed.

The flight conditions for the air ambulance trip consisted of a clear, moonless, dark night and the destination airport was in a mountain valley with the only ground reference lights the town adjacent to the airport. Witnesses saw the aircraft overfly the town and airport at pattern altitude then head out over the lake north of the airport. About 1 mile from the runway, the aircraft was seen to suddenly pitch up, roll inverted and dive straight down into the lake (Bridgeport Reservoir). The aircraft was heading away from the only ground reference lights and was over a reflective body of water near the base turn point when the accident occurred. Witnesses heard increased eng/prop noise before impact. Wreckage revealed evidence of power at impact. The shifts for the pilots in the operation consisted of 4 days on, 2 days off, with alternating day and night shifts. The pilot was on the 4th night of the current shift cycle and was also giving flight instruction during the days. Both occupants, a pilot and a nurse, were killed.

During a local pleasure flight, the pilot had reduced power and descended to a lower altitude to take pictures of a sailboat race. At approximately 200 feet the pilot made a descending right turn, then leveled off. The aircraft stalled and the pilot lowered the nose and abruptly added power. The engines did not respond in time to regain altitude and airspeed. The aircraft then impacted the water left wing first. On impact a fire started. The aircraft eventually sank and was not recovered. All three occupants were rescued, two of them were seriously injured.

The Hercules aircraft took off from Travis AFB at 14:45 for the second of a series of local training flights. Approaches and practice landings were carried out at McClellan AFB before returning to Travis. A runway 21L ILS approach and full stop landing were to be made by a 1st officer candidate. A balked landing forced the captain to take over the controls and initiate a go-around. The no. 1 and no. 2 engines both decelerated when throttles were advanced. The aircraft then banked left and struck the airport perimeter fence in a nose-low and steep left-wing low attitude.