Originally Posted by
jackdiazccs
It sounds like the UAT is under a lot of suction due to restriction in the fuel system (it includes everything ... from the vent all the way to the pump suction nipple).
When you cut the power and the pump voltage drops, the pump may not be able continue sucking fuel at that voltage for a short period of time ... until the pressure from the vent builds up again in the system.
In my experience, rigid UAT's are much more susceptible to cause your issue.
If your UAT isn't rigid, check how much it collapses at high power. That will give you an indication of the amount of restriction.
Jack
Yes Jack, that's a possibility. And yet it happened only when airborne.
If the vent were restricted, and the engine on power were sucking in the header tank and main tank, then when closing the throttle I would get that result, flameout. Now that you mention it, that happened on another model once when I forgot to remove the bung on the vent pipe.
The time it didn't happen on this seaplane was the second last flight when I very very slowly reduced power, and landed with just a trickle of power, and airbrake deployed.
However it didn't happen when I tried to reproduce the fault on the ground, even snapping the throttle shut from high power.
But still, I'll check the vent.
Thanks,
Alasdair