I still do not quite get how to calculate the PNR

[FLIGHT2]

hey guys
I am flying over the ocean RN
and I got a bit less fuel than i wanted, so i when to calculate the PRN

Calculate PNR (point of no return)

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) [image] Hope this helps! Note: For sim use only! (Obviously)

however I still do not get what he means by “Out to home, Endurance Hours”
and ECT can somebody explane it i bit more “easy”

[jhj0604]

PNR = (Ground speed back * Endurance) / (Ground speed back + Ground speed out)

Endurance = Number of hours of fuel on board - reserve fuel

Ground speed back = Ground speed back to initial departure airport

Ground speed out = Ground speed towards destination

Example:
Endurance: 4 hours
Reserve: 45 minutes
True Airspeed = 80 knots
Headwind = 10 knots

Ground speed Back = 80 knots + 10 knots headwind
Ground speed Back = 90 knots

Ground speed Out = 80 knots - 10 knots tailwind
Groundspeed Out = 70 knots

Endurance = 4 hours - 0.75 hours (reserve fuel)
Endurance = 3.25 hours

Take all that information and plug it into the formula:
PNR Time = (90 knots * 3.25 hours) / (90 knots + 70 knots)
PNR Time = around 1.83 hours

[JetA-1]

Perfect, that’s a great way to break it down!
Thanks for the contribution!

[JetA-1]

I understand how difficult this can be at first. this is quite complicated stuff to take in, but. with a little practice, it eventually clicks. just keep reading and ask heaps of questions and you’ll get it in no time! :)