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## Interpolation

• Topic Author

### basketball created the topic: Interpolation

Hi Folks,

I was just wondering what is the correct way to interpolate for performance figures? Or rather, what interpolation means in the aviation context?

My knowledge of interpolation is that it can be quite complex (this is going by what i had to do at university for finance), but i think it may not be very practical for aviation purposes?

Thanks,
Brendan

• Posts: 1169

### Richard replied the topic: Re: Interpolation

Hi Brendon,

We are but simple pilots so interpolation will not be too complex Linear interpolation is all you will need when working with the performance figures and even then it is usually a simple midpoint value e.g. getting a figure for ISA +15 given values for ISA +10 and ISA +20.

Cheers,

Rich

• Topic Author

Thanks Richard!

• Topic Author

### basketball replied the topic: Re: Interpolation

Oh Sorry, 1 more thing with regards to interpolation, what is the accepted tolerances for rounding figures?

E.g. in exercise 4.3 Q 5 , we used interpolation between sea level and 5000 ft for climb performance when say the density altitude was 3600, not exactly halfway between 0 and 5000, but we still assumed it was exactly halfway to get our figures (i guess i was thinking more should be weighted towards the 5000 ft figures due to 3600 being closer to 5000, but the end result probably would not differ significantly from the original answer)

Thanks,
Brendan