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Video Lessons
Air Navigation

CP / PNR Solver

Where is it quicker to continue than to turn back, and where can you no longer return at all? A classic DGCA Navigation question and the basis of long-range fuel decisions.

NM
kt
kt

Negative is a headwind on the way out; it becomes a tailwind on the way home.

min

04:00 of usable fuel, excluding reserves

Engine failure

Try an example

0 NM125 NM250 NM375 NM500 NMDEPDESTCP291.7 NM · 02:55PNR
Critical point291.7NM02:55 after departure
Point of no return233.3NM02:20 after departure
Groundspeed out / home100 / 140kt

How to use it

  1. Set the sector distance, TAS and the wind component on the way out (a headwind out is a tailwind home).
  2. Set safe endurance: fuel time available, excluding reserves.
  3. For engine-failure CP questions, switch on the reduced TAS.
  4. The route shows where the CP and PNR fall between departure and destination.

For learning and exam practice only. Not for operational flight planning: always use your aircraft’s flight manual, official charts and current weather.