enyaengine

Something my club pointed out when I flew my prankster for the first time yesterday (Actually, I flew it 9 times that day . . .), was how short a time the fuel tank seemed to last. So, this morning I decided to find out exactly how long.
Using an OSLA 40, A3 glowplug, Double yellow spot fuel at WOT, I managed to get about 9 mins of run-time (with the HS needle set just a little richer than the highest rpm). Is the acceptable? MY only reason for not putting a bigger tank in is that the plane struggles to take off anyway (uses almost the entire length of the patch). I may put a more powerful engine on, but that will require an even bigger tank (I was thinking a JEN .56). So, the questions are;

1) any idea what tank is in at the moment?

2) is this sort of run-time normal? Or should I be able to keep the engine at WOT for longer?

3) How much more fuel does a .56 engine use over a .40?

Many thanks,

MinnFlyer

My Feedback: (4)

That's really not that unusual. When you consider that you don't usually fly at WOT for most of the flight, you're probably getting more like 12 -15 minutes of run time. That doesn't sound like much, but I would venture to say that most of my flights only last about 10 minutes.

joeb102072

My Feedback: (9)

I would assume you dont have anything more than a 10oz tank approx 1 oz a min of burn time. You could however have an 8 oz and be getting good fuel consumption rates. Thats pretty normal IMO. I have both ends of the spectrum a 40 size profile 3D plane with an 8 oz tank and a YS .63 on it I get about 7 to 8 mins of flight time. Then I have a Giles 300 60 size with a 16 oz tank and a Saito 100 in it. I get about 15 to 18 minutes of flight time. SAitos suck fuel like demons. I had an OS 91 on it and I was almost getting 25 minutes of flight time out of it. I dont think theres a problem at all it sounds normal to me but to make sure yo uneed to find out what size tank you have in there.

RichD

after 12 mins of flying, I am ready to take a break anyways

using a TT .46 pro and an 8 oz tank, I get about 14-15 mins of modest flying, 12 mins if I am pushing it.

enyaengine

Thanks people. I guess the main reason I was using so much fuel was it was quite windy and I was at WOT quite a bit to compensate. I have ordered a JEN .56, I should get that in a few weeks when the delivery comes in. I can't wait!
Paul at Just Engines reckons that I should need a 4 or 6oz tank for .56 . . . but I'll see what happens with the current tank. The engine develops nearly twice the power of the 40LA so perhaps in use, the engine may even run for longer as a lot less throttle will be required. I shall test it anyways before I take the plane up and put a larger fuel tank in if needed.
Thanks again for the help, people.

Dukester

My Feedback: (31)

Don't forget the basics and check the tank plumbing. I had a plane with a Magnum 46 on it that always had slightly shorter runs than I thought it should. Later after deciding to change engines, I peeked in at the tank and the round tank had rotated about 30 degrees, putting the vent line much lower in the tank. Sometimes its the little stuff that gets you.

Duke

enyaengine

Yeah, good one, thanks. I'll check that one out. I suspect that the tank may well be oblong because of the fuselage profile of the Prankster, but I'll look anyway. I bought the plane s/h you see.