Did a series of snaps the other day and the fire went out approx 15 secs later with a tell-tale vapor trail. No other issues in the 4 previous flights or the one subsequent. "Fuel Fail" was the indication on the P-60's data terminal.

The BVM UAT had little/no air in it when examined on the ground, NO bubbles visible in any lines elsewhere. Two tanks in series, large felt clunks in each, aft tank 25% and fwd tank 100% full.

Examining the evidence, I'm nearly certain I ate a bubble as a result of the snaps, which were a first for this model. Perhaps I simply dislodged a "fuel fart" from the JetCat filter, which is mounted loosely and vertically? I will try to replicate the failure in the coming days (with a bunch of altitude), but I would be grateful for your collective input in the meantime.

Thanks all, D.

I have gotten the very same flameout with smoke / fuel fail error... only mine came after sitting for a few months! After cleaning out the system with a few runs...all works great thereafter.

I believe your problem might have something to do with your fuel pump maybe getting weak or a small leak at the pump.

Lee

D,

It really does look like an air bubble went through, like you said once it has gone through, the evidence has gone too.

Bit like full size piston engines and carb ice, it can fail the engine if you get away with it and land in a pasture the engine generally starts on the ground, and no faults found.[]

Try a full power run with the model restrained on the ground and check for bubbles.
Something else to consider, this was mentioned by Duncan on another forum, during aerobatics if the clunk line has aged or gone hard it can come out of the fuel momenteraly, thus sucking air.

Regarding filters the Jetcat ones are generally good if like yours they are mounted vertically, now I know every one has an opinion on this, however myself I would rather not use an onboard filter as I buy clean fuel, filter it in to my fuel station, two filters on the fuel station, and in the model a BVM UAT, but as they say opinions are like @##$$!"% everyone has one.

Lee, I think that it isn't the mentioned pump issue, as that would be a constant and this problem is not.

Thomas, the next flight did not flame out, at full power or otherwise, so I don't think I am making bubbles due to any leaks. I am inclined to retain the filter but will perhaps tap/shake it occasionally to see if micro bubbles are accumulating there.

Thanks for your inputs, hopefully I can experiment more on Monday.

it takes a fair size bubble to put the flame out, i was bench running a P-160 the other day and just used my start up / taxi tank connected to the fuel pump, everything was running like a dream then all of a sudden the RPM started dropping out and i noticed it looked like foam in the fuel line it had so much air in it, the pump was drawing enough fuel that it caused an air funnel in the tank and started sucking air, dropped it back to idle and the air stopped and she kept running.

I'm far too inexperienced to say , but I'm guessing that it takes a significantly smaller bubble to snuff a 60 than a 160. Just guessing.

My plans for Monday, besides trying to replicate the flameout, are to double-confirm that bad fuel was the cause of the previous issues I was having with the 60 and my SS, which you graciously offered advice on in a prev thread a couple of weeks ago. I'll be sure to post here and there what, if anything, I was able to determine.

Used to belong to the Memphis Prop Busters when I lived there...great guys. If its quitting with a resulting smoke trail it's a bubble causing the shutdown. Even tho everything was safetied I replumbed mine and no further flameouts. It was also quitting on inverted snaps...interesting. Never did determine the source of the bubble.

Mike

Then u must know Ed, who waivered me. Great guy, and a selfless asset to the hobby !

If the problem persists tomorrow then I already have another tank in mind. I'm currently running 2 Dubro 40s in tandem/series, but have a 67oz Jet-tech Roo tank waiting on the shelf which would reduce my air time by 2+ mins but also GREATLY reduce the plumbing variables.

SOLVED (I hope)

I have extensively and repeatedly snapped it with no further issues after orienting the JetCat filter vertically with the exit or "downstream" end on top.

I believe that my previous (and only) flameout occurred when small bubbles that would normally have never been an issue accumulated into one larger one, which eventually "burped" during the jostling of a snap. The result was a deadstick into the beanfield and I didn't want to repeat that :-)

Thanks again to all who contributed their thoughts, I am very grateful.