[archerflyer]

Hi All,

sorry if this is a daft question & i've messed up a topic, but I'm doing some take off/landing distance prep and i've come across a scenario I haven't encountered before and not sure on the next steps - thought I'd ask here.

Using the table from the POH for calculating take off and landing distance, what do I do in the event that the pressure altitude would be below sea level?

example:

airfield elevation - 390ft
QNH - 1028
1028 -1013 = 15 *30 =450
390-450 = -60FT

Would I use SL data?

thanks in advance and help much appreciated.