Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10 5/3/83; site odin.UUCP Path: utzoo!watmath!clyde!burl!ulysses!mhuxj!houxm!hogpc!houti!ariel!hou4b!hou5f!orion!odin!dbr From: dbr@odin.UUCP Newsgroups: net.aviation Subject: Contra-Rotating Propellors Message-ID: <329@odin.UUCP> Date: Tue, 9-Oct-84 15:04:27 EDT Article-I.D.: odin.329 Posted: Tue Oct 9 15:04:27 1984 Date-Received: Wed, 10-Oct-84 05:01:08 EDT Organization: AT&T Information Systems, Holmdel NJ Lines: 6 The two closely spaced propellors act as one device. Ideally, the rear propellor straightens out the swirling airflow from the front, improving the overall efficiency. One early use of contra-rotating propellors, and still used, is naval torpedoes. The Russian Tu20 has 4 contra-rotating turboprops.