The end of the avgas piston twin?

Peter – yeah, I mentioned the fuel icing and the pilot being an idiot (empty tanks, wrong fuel!).

Fuel contamination is a good thought and I guess more than likely would result in both engines failing at around the same time. Air duct icing is really the same as fuel ice in that both are related to icing issues which could cause a double engine failure. I nearly mentioned the old DA42 issue.

So there arent many scenarios. Considering each, empty tanks shouldnt come as too much of a surprise, icing could catch you out, wrong fuel and fuel contamination (sort of the same thing) would be a really horrible one and the DA42 issue is very type specific.

So I guess the only one that would really come as a major surprise to the pilot should be the fuel contamination about which you can do very little, other than switch tanks if possible which you might well think about. Of course in some cases there would be signs before departure, but I guess if it was a mild form of contamination it could take a time to catch up with the engine. Has anyone mixed Jet and Avgas by mistake I wonder – I am sure it must have happened?

Fuji_Abound wrote:

Has anyone mixed Jet and Avgas by mistake I wonder – I am sure it must have happened?

There are a few examples.
Here’s one: http://www.sust.admin.ch/pdfs/AV-berichte//1767e.pdf

Aircraft PA31-350 Navajo Chieftain Panther II, HB-LTC arrived in Zurich on Friday 26 May
2000 at 19:10 hrs from Béziers (F) with seven passengers on board. The aircraft was then
incorrectly refuelled with 100 l of JET A-1 kerosene instead of aviation gasoline (AVGAS).
The pilot took off at 20:21 hrs alone on board from runway 28 of Zurich airport in order to
fly back to Geneva. Shortly after take-off, both engines failed and the aircraft crashed while
attempting to turn around. The pilot sustained fatal injuries and the aircraft was destro

Peter wrote:

- empty tanks
- fuel contamination
- wrong fuel

Wrong management of an overly complex fuel system has led to quite a few accidents as well. Aircraft like the C310, C340 and C421A and B come to mind.

Noe – thank you. I guess it sadly had to have happened. I had wondered how quickly it would cause failure which I guess must be a combination of how much fuel was in the tanks already (the dilution ratio) and how long the taxi and run up was. I shall be interested to read the report when I have a sec. and of course just as relevant to SEPs these days with DA40s and “conventional” SEPs often filling up at the same pump station.

Fuji_Abound wrote:

DA40s and “conventional” SEPs often filling up at the same pump station.

In many places, no sticker = no refueling. Pretty strong approach but good prevention. Jet A1 nozzles are made not to fit into Avgas openings, but, as far as i know, an Avgas nozzle will go into Jet A1. Nozzle design could prevent that but would require pretty much every Avgas plane to change it’s design which is not practical.

Peter wrote:

The trickiest one might be the DA40 which is plentiful in both versions.

And the PA46. There was a tragic crash in Washington where a piston PA-46 was filled up with Jet-A at an airport where Jetprop are common.

Peter wrote:

I think the hole is about 5cm.

Some of the Jet A1 nozzles have little “wings” that might make it not fit into some openings:

(but probably fits any sort of non-narrowed opening)

JasonC wrote:

And the PA46. There was a tragic crash in Washington where a piston PA-46 was filled up with Jet-A at an airport where Jetprop are common.

That happened at my former home airport – there was a based Jetprop DLX which the (less than a month in the job) line guy filled very frequently. A visiting piston one arrived and he put Jet-A into it. Fortunately, he or someone at the airfield realised he’d put the wrong fuel in it before the owner came back to fly it.