Announcement

Collapse
No announcement yet.

Question ID: 330421 (Endurance)

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • Question ID: 330421 (Endurance)

    Find the distance to the POINT OF SAFE RETURN (PSR).
    Given: maximum useable fuel 15000 kg, minimum reserve fuel 3500 kg, Outbound: TAS 425 kt, head wind component 30 kt, fuel flow 2150 kg/h, Return: TAS 430 kt, tailwind component 20 kt, fuel flow 2150 kg

    A) 1491 NM
    B) 1143 NM
    C) 1463 NM
    D) 1125 NM (CORRECT)

    Answer explanation:

    Time to PSR = (E x H) / (O + H)

    E = Fuel availabe / fuel flow = 11500 / 2150 = 5.349 h

    E = 5.349 h, O = 395 KT, H = 450 KT

    Time to PSR = (5.349 x 450) / (395 + 450) = 2.849 h

    Distance to PSR = (Outbound GS) x (Time to PSR)
    = 395 x 2.849 = 1125 NM

    My question is: When we calculate the endurance, do we not take all the usable fuel (including reserve)? In this case 15000 kg instead of 11500 (Usable fuel - Reserve).

    Thank you.


  • #2
    Hi
    When filling in endurance on a flight plan we would use all the usable fuel as ATC endurance is to "tanks dry".
    A PSR, however, is the last point we can reach and return to our starting point with our reserves intact.

    Hope this helps.

    Comment


    • #3
      Thanks JJ!

      Comment

      Working...
      X