A recent issue has surfaced where the W&B calculation from SkyDemon has been used for flight planning and the W&B figures entered into the Tech Log. The problem is the total weight on SD subtracts the Start/Taxi fuel, and so there is a discrepancy in the fuel and total weight figures.

This is fine if you're aircraft flight manual uses Max Takeoff Weight as a limit , however if it states Max Permissible Weight as a limit, you can easily fall foul during an audit.

SD is trying to be a little too clever. Can we please have simple W&B calculation that doesn't subtract Start/Taxi fuel.

Also, it's no good to say, set Start/Taxi to zero, as that will impact the fuel calculation.

Regards
Pete

On further investigation, I've found some aircraft profiles subtract Taxi/Takeoff fuel and others don't. The older profiles don't subtract.

Also, I notice in Route > Flight Details > Weight & Balance, at the bottom the older profiles show "Start" Weight & CG, but newer profiles show both "Takeoff" and "Landing" Weight & CG. Could this be related and is there a flag somewhere in the aircraft profile that triggers this difference?

Hi Tim, thanks for the response. At least for now we have a workaround by adding an extra tank although not very elegant.

Is it possible in future we could have an option to force the W&B to use Start weight for those aircraft profiles with only one tank?

Cheers
Pete

Such an option would be used/appreciated by a handful of users out of tens of thousands, unless I'm very much mistaken. So it's very doubtful, sorry. If others would like to weigh in on this, this thread would be the perfect place.

I think a more useful improvement would be to graphically show the more complex W&B parameters on some aircraft. For example, one aircraft I fly (sub 2t SEP) has limits for max ramp weight (higher than max takeoff weight), max landing weight (lower than MTOW), and max zero fuel weight. None of these can be included in the current SkyDemon W&B model.