If you don't get the TAS/Wind etc... you can use the ETP equation to work out the necessary groundspeeds (Home and Out) etc... then use those figures to work out the PNR time etc...
ETP:
https://www.skybrary.aero/index.php/File
TP.png
distance to ETP = (total dist * GS Home) / (GS Home + GS Out)
=> 1200 = 2000 * (H/(H+O))
=> 1200 / 2000 = H / (H+O)
=> 0.6 = H / (H+O)
=> H = 0.6 (H+O)
From here we can deduce that the value of H is 0.6 or 60% of the value of H+O... simply substitute a value for H to work out O...
ie. assume H = 1000
=> (1000+O) = 1000 / 0.60
=> 1000+O = ~1667
=> O = 1667 - 1000
=> O = 667
So, our Groundspeed home to A would be 1000 (tailwind)... and GS to B = 667 (hence why ETP is closer to B)
As per:
https://www.skybrary.aero/index.php/...o_Return_(PNR)
To calculate the
time to PNR, you need to know endurance (in hours), GS Home and GS Out.. Looks like we have elected to take 5000kg fuel... + contingency of 500kg... which is 5000/500 = 10% contingency...
Without an actual fuel burn or endurance figure, I would assume that the 5000kg fuel would have been taken based on our estimated travel time at calculated GS "out", so our basic endurance therefore equates to = 2000 dist / 667 GS out = 3 hrs... then we need to add the 10% due to contingency to get final "safe" endurance => 3.3 hours...
Time to PNR = (Endurance in Hours * GS Home) / (GS Home + GS Out)
=> 3.3 * 1000 / 1667
=> ~1.98
So... 1.98 hrs to PNR * 667 GS out => ~1320 nm
NOTE: I'm not sure that is the "correct" or most efficient way to go about getting from a stated distance, fuel load and PET to the PNR but it seems to work. Was there a fuel burn figure or endurance figure actually given?