Aux fuel level

[Deanrobert]

I had an issue in our da-42ng of “ loosing prime “ on our aux fuel tank , as it wouldn’t transfer . My question : should you leave a gal in the aux of the 62 to prevent loosing prime?

[NDCDA62]

I have never experienced such an issue and run the auxiliary tanks empty upon transfer to the main tanks.

[Boatguy]

I have never experienced such an issue and run the auxiliary tanks empty upon transfer to the main tanks.

+1. But sometimes the gauges report "1" when the CAS reports empty.

[CFIDave]

No need to leave fuel in the AUX tanks of either the DA42 or DA62 (except for tank capacity, the systems are very similar). I'm not sure how you'd know you have 1 gal left in the tank of a DA42, since (unlike most DA62s) there are no DA42 AUX tank fuel gauges.

We flew DA42 and DA62 for 9 years and routinely emptied the AUX tanks completely on longer flights.

[mfdutra]

In practice, there's always some fuel in the aux tanks, as not all fuel is usable.

The fuel level senders (DA62) aren't the same as the micro switches that turn off the pumps when the tanks are empty. So it's entirely possible that the micro switch will turn off the pump while the sender still indicates some fuel. That can easily be resolved by calibrating the fuel senders in the G1000 maintenance mode.

Conversely, the micro switch may be faulty and turning off the pump too early.

[Deanrobert]

Thx