Helicopters

Title: Helicopters
Subject: en Imagined technology & prototypes; en Airplanes and Zeppelins
Article Title and/or Image Caption: Helicopters - Rotating-wing aircraft exhibit desirable characteristics for national defense
Contributor: Alexander Klemin
Language: eng
Temporal Coverage: World War II
Date Issued: 1940-09-01
Is Part Of: Scientific American, v. 163, n. 3, 1940
pages: 138
Rights: Public domain
References: Igor Sikorsky
Archived by: Stefano Furi