This is an excerpt from a report made to the Aviation Safety Reporting System. The narrative is written by the pilot, rather than FAA or NTSB officials. To maintain anonymity, many details, such as aircraft model or airport, are often scrubbed from the reports.
Student preflighted the Pipistrel Alpha Trainer light-sport aircraft and I met him on the ramp. We went over the plane and I did a once over myself of the plane before we started the engine.
Engine oil and fuel was checked. We had 11 gallons of fuel when we took off and the plane takes 13 gallons. The plane gets a 3.2 hour/gallon fuel burn so I knew we had plenty of fuel for practice maneuvers about 10 miles from the airport.
Student started the plane and taxied to run-up. We did the run-up and all instruments appeared to be in the green and at tolerances. I didn’t notice any drops in temperature or fuel.
We taxied to Runway XX and made callout and back-taxied. We did a normal takeoff and climbed out, proceeded crosswind to downwind staying at 850 feet. We proceeded to climb to 1,500 feet and made our way to the practice area.
Student was flying and I ran a cruise checklist and everything looked fine, all instruments in green. We started a climb to 2,500 feet. At 2,000 feet the engine sputtered and we lost fuel pressure and I noticed we had four gallons of fuel. I knew at this point we were losing fuel.
It looked like propeller stopped so I checked fuel valve — it was open — and started engine, turned key, propeller was spinning, and engine was on.
I turned toward the airport and pitched for best glide at 69 knots. I circled to lose altitude and kept throttle low since I knew I had low fuel pressure, but I still had engine.
I was setting up for a landing and was about 400 feet when propeller stopped again and the plane started to sink quickly. I immediately turned into the runway to land and put in flaps since I did not want to overshoot the runway.
We landed hard but on both mains, side loaded on left main and was able to fully brake.
We pulled onto the taxiway and stopped the plane — nobody was in the pattern or at airport.
We checked the gascolator valve under the bottom left of the engine and it was dripping fuel and was partly open. I believe this was why we lost fuel and is a design flaw of the Pipistrel Alpha Trainer.
I think the gascolator valve on the Pipistrel Alpha Trainer should be redesigned so it cannot open and close. It’s also plastic. The gascolator valve should be a stainless-steel spring valve like in most planes that you press a sump can up into and drain gas instead of a plastic switch that can open and fuel flows freely out onto ground.
The current design is dangerous.
Primary Problem: Aircraft
ACN: 2118129
Agcat
They said nothing about the safes agplane ever built!
With that much fuel running out they should have smelled somthing like gas?
‘ I ran a cruise checklist and everything seemed fine, all instruments in the green ‘.
Presumably the checklist didn’t include the fuel quantity gauges in the instruments.
There was a similar incident reported on this thread about a week ago, and a suggestion was made there to verify that the fuel consumption by the gauges roughly corresponded with a time-in-flight figure at least at the top of initial climb , in any a/c. I agreed, but then I’ve always been a worry-wart.
At 1,500’ that difference would ( should ) have been very noticeable in this case.
This is a basic flaw in the design. Who cleared this unit to be used in aircraft ? Doesn’t this amount to criminal negligence ?
Paul
Training should be done in a Real Airplane. This one looks like it should be powered by a rubber band.
Hey, the guy claimed that he only burned 0.31 gallons per hour (3.2 hour/gallon) — so mebbe it Does run on rubber bands.
And Pipistrel doesn’t make the gascolator or the drain valve. Mebbe he should better direct is focus at the true perp instead of the deep pockets — or get out of flying altogether, since he obviously did an inadequate pre-flight.
I’m thinking that if I had just had an engine failure, and was blessed enough to get a restart, I would not have circled to lose altitude several miles from the runway. I would have maintained altitude until I knew I had the runway made. Maybe circle above the airport to lose altitude?
Is my thinking wrong?
I agree Ken. Always “make” the airport when possible.
So I did a preflight and left a drain valve open, didn’t pay attention to it dripping fuel and it’s the aircraft’s fault? And it was leaking enough to dumped 7 gallons of fuel in 20-30 minutes?
I assume they mean 3.2 gallons/hour. If not, that is pretty impressive!