REFLECTOR: Speed brake usage question

[kufalk at wi.rr.com]

What is needed is someone good at aerodynamic engineering who can calculate the force generated at different airspeeds and maybe different deployment angles.  If we knew the forces in play here we could get a better idea on just how strong it needs to be.


----- Original Message -----
From: Scott Derrick <scott at tnstaafl.net>
Date: Monday, November 8, 2004 11:45 am
Subject: Re: REFLECTOR: Speed brake usage question

> I wonder what the factory says about increasing the extension 
> speed to 160 
> kias???  Is it really strong enough for continuos usage at that speed?
> 
> That would make the brake a much more versatile tool.
> 
> My fear is it eventually coming off, right into the prop!
> 
> Scott
> 
> At 07:44 AM 11/8/2004, you wrote:
> >Dave,
> >
> >I've already done the test for you.  One time at 160 IAS I hit a good
> >bump that bumped my head on the ceiling.  My shin bumped several 
> toggle>switches located at the bottom of the panel (not the best 
> place for the
> >switches), including the speed brake switch.  At first I couldn't 
> figure>out why I lost 25kn of airspeed until I saw a few indicator 
> lights on.
> >The brake still works fine with no damage.
> >
> >John
> >SGRE
> >
> >David Scharfenberg wrote:
> >
> > > The maximum airspeed for speed brake extension is 110, which 
> is less
> > > than the gear speed.  On other planes I fly, the speed brakes 
> can be
> > > deployed at any speed.  This helps on a quick decent and helps 
> bleed> > off speed for gear extension.  I have been wondering if 
> the airspeed
> > > for partial speed brake extension would be more than the 
> current 110
> > > limit.  This would make the speed brake more useful.  Of 
> course I know
> > > who sets the actual limit on my plane, but  don't really want 
> damage> > it doing the airspeed tests.
> > >
> > >
> > > Dave Scharfenberg
> > > std/RG
> >
> >
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