Which one of the following instances of performance of aircraft is not considered for determining basic runway length?

Important point:

Basic runway length is calculated with the following assumptions:

i) It is calculated at Mean sea level (MSL)

ii) It is calculated for standard temp 15°C at MSL.

iii) The gradient is assumed to be zero.

Due to the variance of these assumptions, some corrections are applied.

i) Elevation Correction: 7% increase in basic runway length for every 300 m rise above MSL

ii) Temperature correction: 1% increase for every 1°C rise in airport reference temperature with respect to standard temperature at elevation.

Where,

Standard temperature at elevation = Temperature at MSL – 0.0065 × Elevation

This increase is made on the already corrected runway length for elevation.

iii) Gradient correction: 20% increase for 1% of effective gradient.