On 15 Aug 2003 22:58:24 GMT, John Galloway
wrote:

What you guys are discussing is the 'Yates effect'
as described by Derek Piggot in 'Understanding Gliding'
Appendix A and also published in Gliding magazine in
1951 by Dr A.H. Yates.

John Galloway

At least someone gets it.

Also mentioned by Doug Haluza in an article in "Soaring" a few years
ago.

As you enter lift the glider accelerates forward due to the lift
vector tilting forward in the flight direction. Entering sink the
reverse effect occurs. This is a short lived effect for sharp edged
gusts with time constants of the order of 0 .15 to 0.5 seconds for
typical glider airspeeds and wing loadings.
It also has interesting effects on TE varios and is one of the reasons
that TE varios seem much quicker or more "nervous"in response than
uncompensated varios connected to static sources. The other is the
sensitivity of the TE vario to horizontal airmass changes"horizontal
gusts".
There is an article on our website about this.

Mike Borgelt

Borgelt Instruments
www.borgeltinstruments.com