(Ed. Note: Apologies to my source, which on this occasion I failed to record! However, the advice received below should be taken on board by all!)

Ceiling and Visibility

·      How much airspace do I have between the reported or forecast ceilings and the terrain   along my route of flight? Does this information suggest any need to change my planned altitude?

·      If I have to fly lower to remain clear of clouds, will terrain be a factor?

·      How much ground clearance will I have?

·      Do I have reliable ceiling information?

·      Will I be over mountainous terrain or near large bodies of water where the weather can change rapidly, or where there may not be a nearby weather reporting station?

·      What visibility can I expect for each phase of flight? (take-off, en-route, landing)

·      Given the speed of the aircraft, expected light conditions, terrain, and ceilings, are the reported and forecast visibility conditions sufficient for this trip?

·      Are there conditions that could reduce visibility during the planned flight? 

·      (Hint: look for indications such as a small and/or decreasing temperature & dew point spread).

·      Are reported and forecast ceiling & visibility values above my personal minimums?

Aircraft Performance

·     Given temperature, altitude, density altitude, and aircraft loading, what is the expected aircraft performance in respect of?

·   Take-off distance

·   Time & distance to climb

·   Cruise performance

·   Landing distance

·       Are these performance values sufficient for the runways to be used and the terrain to be crossed on this flight? 

*(Note:Remember that it is always good practice to add a 50% to 100% safety margin to the “book  Numbers” you derive from the charts in the aircraft’s approved flight manual (AFM)


·    Are the wind conditions at the departure and destination airports within the gust and  crosswind capabilities of both pilot and aircraft

* (Note: For most GA pilots, personal minimums in this category might be for a maximum gust of 5 knots and maximum crosswind component 5 knots below the maximum demonstrated crosswind component.)

·    What is the manoeuvring speed (VA) for this aircraft at the expected weight?

*(Note: Remember that VA  is lower if you are flying at less than maximum gross weight.)


Tony Birth