Primarily for general aviation discussion, but other aviation topics are also welcome.
By kghjfg
#1391769
Hi all,
My Cessna150/152 checklist says

Throttle closed
Mixture fully lean
Ignition off
Fuel off
Master switch off
Brakes
Exit!

But I think it's

Fuel off
Mixture lean
Throttle Open
etc etc

or some such, to burn off any excess fuel.

Or is that ONLY when starting. Plus, the second one is not in my AFE Cessna Checklist anywhere.
By Joe Dell
#1391772
Had a fire on start-up a few months ago with a 150. Overprimed. The left seat froze. I think I followed the 2nd procedure, without the leaning. It went out anyway. Cleaned up, melted air filter replaced and all was well.
By Balliol
#1391775
Have a read of what the POH for your aircraft says. I think C152 POH Fire on the Ground procedure is for during engine start hence covers what you mention. The checklist one is probably a generic procedure for any fire on the ground, i.e. based on principle of shut down, evacuate and get well away.
#1391776
I would have thought that it's much quicker in a 150/152 to pull the throttle and mixture (as your hand is likely to be on/near them) than to reach down between the seats to push the fuel valve round to the "off" position first?

JS.
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By PeteSpencer
FLYER Club Member  FLYER Club Member
#1391789
Keep cranking and suck all the flames into the engine if it's an overprime fire .

If there's a wall of flame 10ft tall leave the aeroplane....

Peter
By chipmeisterc
#1391827
kghjfg I had the same confusion recently when reviewing the very same checklist. 'Fire on the ground' seem to refer to a generic aircraft fire whilst on the ground as opposed to an engine fire during startup.

That said, what does an overpriming fire look like? Smoke/flames? Exhaust? Also assuming you do successfully suck it back by cranking then what? Immediately shut down and inspect for damage? Keep running for a few minutes then check?
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By Smaragd
FLYER Club Member  FLYER Club Member
#1391896
Smoke certainly. If you get to flames you can see from the cockpit it's probably gone beyond the sucking back in stage and is time to get out. Keep running - no, because you've already turned the fuel off.
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By Ridders
FLYER Club Member  FLYER Club Member
#1391910
The overpriming fires I have seen from watching people trying to start are a burst of flames, with no real smoke. It's the fuel burning.
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By Smaragd
FLYER Club Member  FLYER Club Member
#1391969
Ridders wrote:The overpriming fires I have seen from watching people trying to start are a burst of flames, with no real smoke. It's the fuel burning.

Over the years I have experienced a couple of overpriming fires (usually in cold conditions) of which I was aware, having been alerted by smoke. Possibly from charring paint on the airbox or oil tank rather than from the burning fuel itself. There have been a couple of occasions when I have only become aware subsequently, from a deposit of soot around the oil tank. I've learned something on each occasion - particularly don't be in a hurry to reprime after a failed start or to pump the throttle excessively (on those carbs with an accelerator pump) to try to catch a reluctant engine . You might have a small fire of which you are not aware, and which will soon burn out - but you'll have a bigger one if you add more fuel!
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By Josh
#1391971
Power off, mixture off, fuel off, battery off, bugger off. Works in most piston aircraft ;)