[MilCom] Best size lens for ground to air photos

[Joe Cobb]

OK everyone.   This is for all of you who have
experience taking pictures at airshows and such.  I
have a Nikon D50 digital SLR camera.   What size lens
would be best for taking pics of aircraft in the air
while i'm on the ground?  I have heard 70-300mm is the
absolute minimum.  Does it need to be higher?  400mm? 
500mm? Thanks for the help.

Joe

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