The private pilot was conducting a personal, cross-country flight. He reported that, when the Cessna 152 was about 12 miles from the departure airport, the engine started running roughly, and the airplane was “violently shaking.”
He decided to conduct a forced landing in a field near St. Augustine, Florida. During the landing, the nose landing gear dug into the soft ground and the airplane flipped over.
Post-accident examination of the engine revealed that the No. 4 cylinder exhaust valve was fractured, and although the head of the exhaust valve was not recovered, the fracture features on the exhaust valve stem were consistent with fatigue.
A review of maintenance records revealed that the exhaust valves were installed during an overhaul of the engine about 28 years before the accident. The engine manufacturer recommended that the engine be overhauled every 12 years or 2,400 hours, whichever comes first.
Probable cause: The partial loss of engine power due to a fractured exhaust valve, which resulted in a forced landing on unsuitable terrain and a subsequent rollover.
NTSB Identification: ERA18LA259
This September 2018 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.
Kudos to the pilot. Good suggestion regarding regular bore scope use in Annuals or 100 Hours. I don’t know of many AI or A&P in the North Central or NE Washington area, other than a Federalie or two, who regularly borescope GA piston engines. Could be age related… Most I mechanics I’ve met in the GA shops were taught when Borescopes were VERY expensive..
Regular Bore Scope examination of valves at Annual / 100 hr Inspection will eliminate fractured valve problems. This type of failure exhibits a heat signature long before actual failure or separation occurs.
So your headline blames the roll over on the valve instead of possible poor soft field technique of the PIC
High wing tricycle landing gear light planes routinely flip over when making a forced landing on a soft surface. Why blame the pilot?
I’ve seen a lot of low wings on their backs, too. Are high wings more prone to do this? Center of gravity/momentum kind of thing?
There are some fields that are so soft there’s little you can do from planting the nose gear and ending on your back.
Freshly plowed or wet and muddy or deep soft sand. Ideally, you’re touching down as slowly as possible and holding the nose up as long as you can so that the tip over is gentle. There is no mention of injury to the pilot so, all in all, he must have done a good job. Give him a little credit.
The NTSB report says: “When the airplane was 200 ft. above the field, the pilot could see crops that were higher than he thought, but he could not turn away at that point.” Good on him. A smart decision—way better than a late switch to a Plan B, like trying to make a 180-turn and land on that road you already passed; or trying to stretch your glide to reach that flat-looking field that’s just beyond some trees, only a bit farther ahead, but that somehow keeps getting higher in your windshield…
I can picture him down at extremely low altitude, in a slow speed “no man’s land” between loss of elevator authority and “contact with the surface”, and not knowing what it’s really like under those crops. Adding to the stress; now he’s also got something slapping and grabbing at his landing gear/gear legs, intent on pitching him over on his nose.
I agree with Ken T: I think he did all right.
“If it ain’t broke, don’t fix it” should not apply to aircraft parts because it’s unlikely to break at a convenient time or place.
28 years ago the parts were installed during an OH, according to the logs. That’s a loooong time to expect them to perform. There’s a reason the Mfg has suggested OH schedules.
Glad auto-truck and equipment manufacturers don’t use 12 years or 2400 hour rules as an excuse instead of bragging about 50 years and 300,000 miles and still running strong!…😆