777 drogue chute on tail
ian...@cadvision.com
the 777 I noted that during ground trials and the initial flight
the following. At the top of the fin there was what appeared to be
a small parachute drogue on a line some 10 to 20 metrs in length.
Difficult to determine the exact size as scale on the 777 is hard
to establish.
Any one else noticed and, more to the point, what was the purpose
of such a device.
Also, seems the dihedral, at least when in flight, is significant.
I have a print of a side on shot and both wingtips are in view
above the fuselage.
Ian
Ian Kershaw, Executive Director
Deaf and Hard of Hearing Services, Calgary, Alberta, Canada
(403) 282 7006 fax
Visit our web site at- http://tiger.ab.ca/hearing
Jim Wolper
flight test to aid in the recovery from an accidental spin. Lest
you think this is unlikely, during one early test of the 777's
stall characteristics it rolled 110 degrees (ie, past vertical)
prior to recovery. This was fixed by a software adjustment to the
aileron control laws.
Jim Wolper CFII
Department of Mathematics <email: wol...@pequod.isu.edu>
Idaho State University <http://math.isu.edu/~wolperj>
Pocatello, ID 83209-8085 USA
C. Marin Faure
> In viewing a recent re-run of '21st Century Jet' which highlighted
> the 777 I noted that during ground trials and the initial flight
> the following. At the top of the fin there was what appeared to be
> a small parachute drogue on a line some 10 to 20 metrs in length.
> Difficult to determine the exact size as scale on the 777 is hard
> to establish.
That is not a drogue chute, but a stabilizing cone for the trailing static
pressure line. In flight, the line is let out to provide a static
pressure source far from from the influence of turbulent air around the
airplane. There was also a trailing wire that extended from the tailcone
on WA001.
C. Marin Faure
author, Flying A Floatplane
C. Marin Faure
(Jim Wolper) wrote:
(in answer to question about small chute-like object off tail of 777
observedin TV series about the plane.
> This was probably a "spin chute". These are commonly used during
> flight test to aid in the recovery from an accidental spin. Lest
> you think this is unlikely, during one early test of the 777's
> stall characteristics it rolled 110 degrees (ie, past vertical)
> prior to recovery. This was fixed by a software adjustment to the
> aileron control laws.
The roll problem and correction description is correct. The spin chute is
not. The small trailing cone the original poster observed is a stabilizer
for the long trailing wire static source we reel out of the plane to get
static pressure readings free of any air turbulence near the plane
itself. It is used on all Boeing planes that are in Flight Test. The
cone does the same thing that the cone on a Navy's refueling hose does-
keeps the cable from whipping about.
Mary Shafer
> In viewing a recent re-run of '21st Century Jet' which highlighted
> the 777 I noted that during ground trials and the initial flight the
> following. At the top of the fin there was what appeared to be a
> small parachute drogue on a line some 10 to 20 metrs in length.
> Difficult to determine the exact size as scale on the 777 is hard to
> establish.
cmf> That is not a drogue chute, but a stabilizing cone for the
cmf> trailing static pressure line. In flight, the line is let out to
cmf> provide a static pressure source far from from the influence of
cmf> turbulent air around the airplane. There was also a trailing wire
cmf> that extended from the tailcone on WA001.
A little more information on trailing cones may be found in the air
data section of the "How to Instrument a Research Aircraft" document
on my home page (address in signature), with a lot more about air
data.
--
Mary Shafer NASA Dryden Flight Research Center, Edwards, CA
SR-71 Flying Qualities Lead Engineer Of course I don't speak for NASA
sha...@ferhino.dfrc.nasa.gov DoD #362 KotFR
URL http://www.dfrc.nasa.gov/People/Shafer/mary.html
David G. Davidson
measurements that are not in the vortex of the airplane.
Dave
trist...@aol.com
http://members.aol.com/tristar500/l1011
"The Unofficial Lockheed L-1011 TriStar Page"
Pete Mellor
> The small trailing cone the original poster observed is a stabilizer
> for the long trailing wire static source we reel out of the plane to get
> static pressure readings free of any air turbulence near the plane
> itself. It is used on all Boeing planes that are in Flight Test.
The same cone and line are clearly visible on both of the publicity
photos I have of the A320 and A340 (presumably taken during flight test).
Pete
----
Peter Mellor, Centre for Software Reliability, City University, Northampton
Square, London EC1V 0HB, UK. Tel: +44 (171) 477-8422, Fax: +44 (171) 477-8585
E-mail: p.me...@csr.city.ac.uk