View Single Post
  #7  
Old October 6th 12, 10:51 PM posted to rec.aviation.soaring
Martin Gregorie[_5_]
external usenet poster
 
Posts: 1,224
Default Aerobatics in semi acrobatic certified sailplanes

On Sat, 06 Oct 2012 13:31:44 -0700, philplane36 wrote:

On Sunday, 7 October 2012 07:38:04 UTC+13, Martin Gregorie wrote:
On Sat, 06 Oct 2012 10:59:58 -0700, son_of_flubber wrote:

What are the G forces in unintentional aerobatic maneuvers... say
flying through extreme rotor?


Have there been cases of gliders losing their wings in rotor on their
way to mountain wave?


A Nimbus 4 broke up in severe turbulence during practice for the 1995
World Champs at Omarama, NZ:

http://aviation-safety.net/wikibase/wiki.php?id=29823


That glider was overspeed and in cloud, so not really a case of G
induced failure.

I fly in the wave a lot, and used to fly a DG1000 with a G meter. The
most I saw in rotor was around 4G positive and maybe 1.5G negative.

I was responding to the 'loosing wings in rotor' comment, not the
'aerobatic G' one. I thought I'd heard it was an overspeed in rotor
situation but the report I dug up didn't mention that so neither did I,
in order to avoid speculating.

I do remember a ridge crossing that was particularly rough that got 5G
positive and 2.5G negative once. That was very unpleasant.

Sounds nasty.


--
martin@ | Martin Gregorie
gregorie. | Essex, UK
org |