FLIGHT MANUAL FOR P-39 AIRACOBRA (AIRCRAFT MANUAL SERIES)

EXTRACT FROM THE INTRODUCTION

"A projectile within a projectile" best delineates the vague notion held by a small group of visionary aeronautical engineers. Theirs was no more than an illusory idea about a particular feature of a particular piece of equipment, and stemmed from a statement made in 1918 by the famous French engineer, Marc Birkigt, who said: "... the best place for an anti-aircraft gun was in an airplane." Theirs was a feeling that an explosive-shell gun, as large as possible, should be put into the air.

It would not require any larger bullets to put a man out of action in 1937 than in 1918. But when the engineering staff of the fledgling Pell Aircraft Corp. began developing the concept of their new fighter airplane they envisioned something that would be able to do more than kill or injure unprotected individual enemy soldiers. What they had in mind was an airplane capable of cannonading explosive shells powerful enough to attack successfully an armored division or a fleet of mosquito (PT) boats and, last but not least, to vanquish the biggest and highest flying bomber.

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