Advanced Navigation Calculations

PNR & ETP Calculator

Required calculations for CASA / FAA commercial navigation exams. Determine your Critical Point (ETP) and safe Point of No Return (PNR).

Route Details

Exclude reserves

Ground Speed Data

Navigation Points

Point of No Return (PNR)

Time to PNR
2h 3m
Distance to PNR
245 nm

Equitime / Critical Point (ETP)

Time to ETP
1h 8m
Distance to ETP
136 nm
Converge & Diverge: Winds will cause your ground speeds to differ heading out versus returning home. ETP determines the equal time point between destinations, whereas PNR tells you the absolute boundary limit for returning safely to departure base before fuel exhaustion.
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