A useful template to calculate the furthest Distance removed from an aerodrome that you may travel and safely return with an adequate fuel reserve remaining. This is especially useful when traveling on large overwater legs on the sim or remote areas without an alternate destination. The formula is as follows;
Endurance in hours (- Fuel reserve) X Groundspeed out to destination X Groundspeed home / ( Out + Home)
You should add in the denominator instead of multiplying. The dimensions of the numerator are length squared per time so you need to divide by length per time to end up with just length. That gives you the distance to the pnr.
In other words it should be:
Endurance in hours (- Fuel reserve) X Groundspeed out to destination X Groundspeed home / ( Out + Home)
From there if you want the time to the pnr just divide that^ by ground speed outbound.
Just making sureš¤£
And just to add on to what MrMrMan said. Endurance = Ammount of fuel / the rate at which it is consumed (this will be displayed in HRS. X the result by 60 if you want it in mins)š¤
Isnāt this literally useless in IF unless you think youāll run out of fuel?
Like this kind of planning is only used in case of engine failure right?
Thatās more the equi time point (CP) formula. The point of no return takes into account en-route winds so if youāre over the water in a C172 and find that the wind is a lot stronger than anticipated, you can calculate if you should go back or press on. I referred to this formula countless times when flying from Colombo to Nagpur in India when doing a circumnavigation in a C172 ( on IF sadly) and calculated that if I pressed on iād land With only 7 mins of fuel remaining which I did.
Hi there, thanks for bringing this!
I wonder if there is a little mistake though. What I find online is Endurance Ć GS back / GS out + GS back
Am I right?
I just checked the notes and found that my explanation was fine. There are multiple ways of working this out. Iāve only done the method that Iāve posted but Iām keen to cross-check!!
Well skyvector shows you the flight time. Other than a couple of exceptions (E170 looking at you), the fuel time estimate is less than the actual flight time you can get out of the aircraft. I add 30 for takeoff and landing, 30 for diversion, 30 for emergency and 5% or 15 for contingency. I have proper fuel numbers for some aircraft and for that I do the same.
Yeah thatās a really good way to break down Fuel planning, because it doesnāt matter whether youāre in an A380 or a cub you always have a personal minimum ātemplateā That you can refer too