MacDonald, Alexander Forsyth, 1897-1965 · Port Credit, Ont. : Aviation Service Corporation · leaf 52
Fig. 13. Cumulonimbus. Nacreous clouds are Imown to exist in the Strato-sphere at a height of 20 miles and Noctilucent (nightluminous) clouds in the Ionosphere at heights of 50 or60 miles. These, however, are beyond the scope ofthis manual. Sky Condition There are five general types of sky:1.…
Airplanes
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