SkyDemon Forums

Fuel calculation in percentage

http://forums.skydemon.aero/Topic39096.aspx

By CGa - 7/27/2026 6:01:22 PM

Hi there,
Would it be possible to add fuel calculations in percentages?
As a helicopter pilot flying the AS350 and AS355, I normally plan fuel as a percentage. The fuel gauges in these helicopters also display the remaining fuel in percent.
In the aircraft profile, the capacity of each tank can already be entered—for example, 540 litres. During flight planning, it would be very useful to display the remaining fuel optionally as:
Percentage (litres)
For example: 35% (189 litres)
Also for crosscheck in pilotlog it would be great: FuelR: xx%
That i can see immediately that everything works fine and planned. 
At the moment, when the helicopter’s fuel gauge shows 35%, I first have to calculate the corresponding quantity in litres:
Fuel quantity = percentage × tank capacity ÷ 100
I then have to enter this value manually. In the AS355, this calculation must be performed twice because the aircraft has two separate fuel tanks.
It would therefore be helpful if fuel could also be entered directly as a percentage, with SkyDemon automatically calculating the corresponding quantity in litres based on the tank capacities defined in the aircraft profile.
Additionally, it would be useful if SkyDemon could calculate the fuel remaining across a trip with several landings. For example, if a trip contains three landings, the fuel for each subsequent leg should be based on the calculated remaining fuel from the previous leg, until fuel is manually added at a particular landing.
At present, SkyDemon appears to assume full fuel for every leg, rather than carrying the calculated remaining fuel forward through the complete trip.
Thank you for considering these improvements.
By GalaxyzA11+ - 7/31/2026 9:07:29 PM

grahamb - 7/31/2026 7:22:19 AM
GalaxyzA11+ - 7/30/2026 8:25:18 PM
Clemens Gassner - 7/28/2026 6:18:51 PM
GalaxyzA11+ - 7/27/2026 9:10:39 PM
Clemens Gassner - 7/27/2026 6:01:22 PM
Hi there,
Would it be possible to add fuel calculations in percentages?
As a helicopter pilot flying the AS350 and AS355, I normally plan fuel as a percentage. The fuel gauges in these helicopters also display the remaining fuel in percent.
In the aircraft profile, the capacity of each tank can already be entered—for example, 540 litres. During flight planning, it would be very useful to display the remaining fuel optionally as:
Percentage (litres)
For example: 35% (189 litres)
Also for crosscheck in pilotlog it would be great: FuelR: xx%
That i can see immediately that everything works fine and planned. 
At the moment, when the helicopter’s fuel gauge shows 35%, I first have to calculate the corresponding quantity in litres:
Fuel quantity = percentage × tank capacity ÷ 100
I then have to enter this value manually. In the AS355, this calculation must be performed twice because the aircraft has two separate fuel tanks.
It would therefore be helpful if fuel could also be entered directly as a percentage, with SkyDemon automatically calculating the corresponding quantity in litres based on the tank capacities defined in the aircraft profile.
Additionally, it would be useful if SkyDemon could calculate the fuel remaining across a trip with several landings. For example, if a trip contains three landings, the fuel for each subsequent leg should be based on the calculated remaining fuel from the previous leg, until fuel is manually added at a particular landing.
At present, SkyDemon appears to assume full fuel for every leg, rather than carrying the calculated remaining fuel forward through the complete trip.
Thank you for considering these improvements.

Hi, about the last point, you have in "route" the "trip overview " where you can chose fore each airfields for which you chose "land here" to " use the remaining fuel" or chose " fuel plan" to refill.
But it works only for a single tank actually. With multiple tanks the button did not appears.
Anyway really usefull to me. I merged my tanks.

Oh, i've never seen this button. Thx for the tip. And yes, its not appearing with more than one tank. So this is bad. Your workaround works, but doesn't help really #WeightAndBalance

"So this is bad. Your workaround works, but doesn't help really #WeightAndBalance”
Do you mean you have 2 fuel tanks on your As350 ? 
Or that your 2 fuel tanks on the As355 are not balanced ?
How could the manufacturer miss that point ?! Realy bad 😉




I think you’ll find that the AS355 has a front tank and a rear tank, so very significant as regards weight and balance compared to an aircraft with two wing tanks at the same lever arm. 

I was joking Graham.