Xref: utzoo rec.aviation:7115 comp.graphics:2437 Path: utzoo!mnetor!uunet!husc6!bloom-beacon!mit-eddie!uw-beaver!uw-june!uw-entropy!dataio!bright From: bright@Data-IO.COM (Walter Bright) Newsgroups: rec.aviation,comp.graphics Subject: Re: JAL 747 crash film (what's a Dutch Roll?) Message-ID: <1541@dataio.Data-IO.COM> Date: 9 May 88 17:56:36 GMT References: <7237@mhuxd.UUCP> <778@scubed.UUCP> Reply-To: bright@dataio.Data-IO.COM (Walter Bright) Organization: Data I/O Corporation; Redmond, WA Lines: 20 In article <778@scubed.UUCP> rankin@s3mickey.UUCP (Tom Rankin) writes: >In article <7237@mhuxd.UUCP> wolit@mhuxd.UUCP (Jan Wolitzky) writes: >>...The Dutch rolls performed by the plane after losing most of its >What, pray tell, is a Dutch Roll?...no relation to a Danish, I >presume :-). Inquiring minds want to know. Dutch roll occurs when you have yaw instability. (The three axes of rotation are pitch [nose up/down], roll [wing up/down] and yaw [nose left/right].) With yaw instability (common when you lose the rudder!), the tail moves side to side. This causes the left/right wings to have more/less lift, which adds an element of roll and pitch. The net result is the plane traces a corkscrew path. The effect I am told can be quite sickening to the passengers. The last episode of "Test Pilot" on PBS showed a wonderful film of a plane doing a dutch roll. By the way, Dutch people are from Holland! The word dutch is a corruption of 'Deutsch', which means German. Somehow it got misapplied to people from the Netherlands.