Aviation & Aeronautics
Intermediate

Point of No Return

Farthest distance an aircraft can fly and still return with available endurance.

Formula

PNR=E⋅GSout⋅GSbackGSout+GSbackPNR = \dfrac{E \cdot GS_{out} \cdot GS_{back}}{GS_{out}+GS_{back}}

Variables

PNRDistance to PNR
EEndurance (h)
GS_{out}Ground speed out
GS_{back}Ground speed back

Example

The PNR is the last point where a flight can still turn back with the fuel it carries.

Did You Know?

The point of no return is where continuing uses the same fuel as turning back — critical over oceans.

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