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Old 31st Aug 2013, 01:52
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tdracer
 
Join Date: Jul 2013
Location: Everett, WA
Age: 68
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Large, low wing commercial aircraft tend to have nasty Dutch Roll characteristics (high wing aircraft are generally much better). While there are some design characteristics that can reduce Dutch Roll, for the most part they tend to make other aspects of aircraft handling/control worse.....

The exception is the yaw damper - a properly functioning yaw damper makes Dutch Roll a non-issue. A yaw damper is pretty much what it sounds like - an automated system that moves the rudder automatically to address oscillatory yaw behavior.

I've always heard the 707 Dutch Roll behavior was really bad (with regard to what aterpster wrote - I hadn't heard the 727 was as bad or worse than the 707 - not disagreeing, just relating Boeing tribal lore).

The last fatal Boeing Commercial flight test crash was a 707 back in 1959. Boeing had introduced a new 707 yaw damper, and the customer pilot was doing his best to test it out by making large control inputs to induce Dutch Roll. One of the inputs was so severe that the subsequent recovery resulted in engines 1, 2, and 4 departing the aircraft . The loss of three engines and associated damage was such that they couldn't make it back to an airport and had to set it down in a field north of Seattle. Four of the eight occupants didn't survive. The story as I heard it was, the pilots and flight engineer stayed in the flight deck, while the other occupants braced for the crash in the back - those in the flight deck perished while those in the back survived.

ASN Aircraft accident Boeing 707-227 N7071 Arlington, WA

Last edited by tdracer; 31st Aug 2013 at 01:54.
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