Safety Accident Reports Murphy’s law... Steve Ayres summarises and comments on accident reports from around the world and looks at CAROL, the new incident search facility provided by the FAA…
Don’t assume… Cessna 172 N92036 Colchester, Illinois Injuries: One serious
The private pilot reported that he checked the fuel tanks prior to take-off. It was dark in the hangar when he used a wire to check the fuel level in the tanks. He was not wearing his glasses and he thought he had ‘an inch or so’ of fuel, which he thought was enough, and departed on a cross-country flight. During the flight, the engine ‘sputtered’ and lost power. The pilot turned the aeroplane towards the destination airport but lost airspeed, so he lowered the nose and conducted a forced landing into the trees. The fuel tanks were empty and there was no fuel odour anywhere at the accident scene. Comment While the old wartime adage ‘don’t assume, CHECK’ couldn’t be more appropriate than in this accident, sometimes it helps to think ‘what would happen if I assumed incorrectly…?’. Not quite so catchy, I agree, but the consequences of ‘assuming incorrectly’ are often too great to be ignored!
panel. They attempted to isolate the problem by operating the master switch gang bar, which switches off the battery and electrical generators, but this had no effect, so they declared a Mayday. The first officer tried to reach the fire extinguisher under his seat but found this to be difficult because of his shoulder straps. After landing, the crew evacuated the aircraft on the runway and the airport fire service attended, but the smoke stopped without intervention when the aircraft was shut down. The investigation concluded that the most likely scenario is that rainwater entered the cockpit through the storm window, which is above the CB panel. Comment This is a stark reminder that water can cause fires, as well as put them out – where electrics are concerned! Reflecting on how to isolate those electrical circuits is important too but as in this case your fire extinguisher may end up as your last line of defence – if you can get to it!
Stuck drain Piper PA-28 G-BZDA
Short circuit Beech B200 G-YVIP Bournemouth Airport, Dorset Injuries: None
The aircraft was on final approach to Bournemouth Airport in clear weather, at a height of about 1,200ft. Very shortly after selecting approach flap, the crew noticed a yellow glow and smoke coming from behind the commander’s circuit breaker (CB)
White Waltham, Berkshire Injuries: None
The accident flight was the fourth instructional flight of the day in G-BZDA for the instructor who was also the PIC. While his student undertook cockpit preparation, the instructor carried out a transit check in accordance with the PA-28 checklist. In addition to the transit check, he sampled fuel from both wing tank fuel drains and from the gascolator. During the after-start checks it was noted that
“The crew noticed a yellow glow and smoke coming from behind the panel” 52 | FLYER | Summer 2021
fuel pressure dropped when the fuel pump was turned off but stayed within the green range on the gauge, indicating to the instructor that the system was functioning satisfactorily. The engine parameters were in the normal range during the ‘before take-off’ power check. On the take-off roll the aircraft accelerated as expected but as G-BZDA climbed through 100ft its engine abruptly ran down. The instructor took control, lowered the nose and looked for a suitable landing area, while simultaneously transmitting a brief Mayday call. The engine then recovered to full power, so the instructor gently raised the nose to climb away. He had just started cancelling the Mayday when the engine ran down for a second time and stopped. With a railway line ahead, the instructor turned the aircraft hard left towards open ground and executed a forced landing. Although the nosewheel collapsed during the landing, the student and instructor were unhurt and able to vacate the aircraft without assistance. This accident resulted from the aircraft’s gascolator drain valve being inadvertently locked open after a fuel sample had been taken, causing partial fuel starvation and a loss of power when the aircraft was climbing shortly after take-off. The investigation found evidence dating back to 1975 that lockable gascolator drains were an identified hazard. Following this accident the CAA released a safety notice reminding owners and operators of this potential hazard for any aircraft fitted with lockable gascolator drains and recommending replacement with ‘suitable, non-locking alternatives.’ Comment I must confess to not having thought through the significance of a fuel drain sticking open downstream of the fuel selector valve. During a pre-flight inspection and with the fuel selected ‘off’ the gascolator will stop discharging fuel when emptied, only to start again when the fuel is selected back to ‘on’ during start. Now that’s a real ‘Murphy’!
