SESKStuff Everyone Should Know
SESK: Stuff Everyone Should Know · sesk.info/pilot-performance-chart-interpolation

How do you estimate a value between two entries on an airplane performance chart?

Use interpolation between the known values.

Start playing free

  1. Extrapolation
  2. Rounding up
  3. Interpolation ✔

Why: Performance tables cannot print every possible condition. Interpolation uses the known values on either side to estimate the missing value between them.

Huh, didn't know that: Some pilots round chart values toward slightly worse conditions, which gives a conservative estimate.

The dad joke
Interpolation likes the middle seat because it belongs between known points.
Like this card?
Play the game

References

Answer: Interpolation. Performance tables cannot print every possible condition. Interpolation uses the known values on either side to estimate the missing value between them.

  1. FAA Pilot's Handbook of Aeronautical Knowledge, Chapter 11 www.faa.gov/sites/faa.gov/files/13_phak_ch11.pdf
    Interpolating information means that by taking the known information, a pilot can compute intermediate information.
    Checked 2026-10-09.

Think this answer is wrong? Tap "Challenge this answer" on the card in the game and tell us why.

Test yourself in the game

Flying & DronesMay a Part 91 pilot replace paper charts with a qualifying electronic flight bag?Flying & DronesWhich time abbreviation is commonly called Zulu time in aviation?Flying & DronesWhat kind of information does a NOTAM provide?

That's stuff everyone should know.