Just finishing up my 9A(IO320-D1A Silverhawk) and done some initial ground runs. I have seen this referenced before that you only use the fuel pump for about 2 seconds to prime on start. Any more and you put fuel into the FAB and it leaks out through the hole in the FAB there for that purpose. I also confirmed this by leaving it on a sec or so longer than that, kind of shocking how much fuel comes out.
My question is what happens in ground running or in flight when your run the boost pump? The thought of flooding fuel/vapor into the fwf with a hot exhaust manifold near by scares me. Does this not happen when the engine is running and you use the boost pump? Or is this only an engine off thing? It seems like the boost pump is going to provide way more than needed while the engine is running and this would happen while then engine is running?
Some of the hot start procedures also seem like the would create this kind of fuel leak into the FWF.
I googled quite a bit for this but could not find any guide to this. Clearly people are using boost in different phases of flight, what don't I know here?
My question is what happens in ground running or in flight when your run the boost pump? The thought of flooding fuel/vapor into the fwf with a hot exhaust manifold near by scares me. Does this not happen when the engine is running and you use the boost pump? Or is this only an engine off thing? It seems like the boost pump is going to provide way more than needed while the engine is running and this would happen while then engine is running?
Some of the hot start procedures also seem like the would create this kind of fuel leak into the FWF.
I googled quite a bit for this but could not find any guide to this. Clearly people are using boost in different phases of flight, what don't I know here?
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