During the approach at night, the Bellanca 17-30A experienced a total loss of engine power, and the pilot performed a forced landing into trees near Monroe, Ga., seriously injuring two.
Subsequent examination of the engine revealed that the oil filter adapter was loose and that it was installed incorrectly with two copper crush gaskets rather than with one copper crush gasket and one fiber gasket per the manufacturer’s installation instructions.
The fiber gasket would have held the required torque for the fitting; however, the copper crush gasket did not hold the required torque.
Because the oil filter adapter was loose, oil leaked from the engine, which led to the failure of the Nos. 4 and 5 connecting rods due to a lack of oil lubrication.
The oil filter adapter was not original equipment on the engine. Although it could be installed under a supplemental type certificate, a review of maintenance and aircraft records did not reveal any entry or record pertaining to the installation of the oil filter adapter.
The airplane had been operated for about 70 hours since its most recent annual inspection, which was performed about a year before the accident.
It could not be determined when the oil filter adapter was incorrectly installed.
Although the pilot stated that he had fueled the airplane with 100 low-lead aviation gasoline, automobile gasoline was recovered from the fuel tanks.
The higher-compression ratio engine was not designed or approved to operate on automobile gasoline, and engine examinations revealed that it had been operating at higher temperatures due to the use of automobile gasoline.
If the engine had not failed due to oil starvation, it is likely that it would have soon begun to detonate due to the use of the improper fuel.
The NTSB determined the probable cause as the improper installation of the oil filter adapter at an unknown time, which resulted in an oil leak and subsequent oil starvation to the engine.
NTSB Identification: ERA14LA436
This September 2014 accident report is provided by the National Transportation Safety Board. Published as an educational tool, it is intended to help pilots learn from the misfortunes of others.
In the above situation I wonder if the oil pressure was reading low and the pilot failed to see it.
The pilot’s first two comments are lessons well learned. It really hurts bad to hit the panel even if you are only going about 20 or 25 mph when you do. I will never again fly an airplane without a shoulder harness. Aircraft engines are scary reliable, however, if one quits on you at night, you might wish you had been flying during daylight hours. Most birds don’t fly at night either.
The pilot report from the docket it interesting. This 400+ hour pilot performed the emergency engine fire procedures well, and made a survivable landing. Unfortunately his aircraft only had lap belts so both he and his female passenger sustained serious injuries (not specified, but likely because of flail and head injuries). His “lessons learned” recorded in the pilot/op report are interesting:
“1- Unless absolutely necessary- I will not operate a SEL aircraft at night.
2- Due to the nature and duration of our injuries, I will not own an aircraft without shoulder harnesses again.
3- I had desired to leave with at least 1.5 hours of daylight but due to my passenger being late we departed late. Here forward I will not allow a deadline departure to be waived when considering “Go/No-Go.”
4- I now set my personal minimum for night flying with a minimum AGL of 5,000 feet under a VFR flight to give me more time and options in the event of an engine failure or other problem.”
He said he fueled with 100LL, but accident investigators found MoGas was in the aircraft tanks. Investigators attributed evidence of high engine temps to operating MoGas in the high compression engine. They also found evidence that, regardless of the incorrect installation of the oil filter adaptor that resulted in severe oil loss and engine fire, the engine would likely have failed anyhow from affects of the improper fuel. Moral: Save a few bucks now and spend a lot later (if you survive).