[NSRCA-discussion] 747 Snap Entry?

[billglaze]

Never tried a snap, but with the instructor's urging, I did do a spin in a 
767 simulator.  The technicians were mad as hell; it took them 45 minutes to 
re-set the device.  We never actually admitted it was on purpose.
----- Original Message ----- 
From: "Koenig, Tom" <Tom.Koenig at actewagl.com.au>
To: "General pattern discussion" <nsrca-discussion at lists.nsrca.org>
Sent: Monday, June 30, 2008 10:25 PM
Subject: Re: [NSRCA-discussion] 747 Snap Entry?


> Hey John,
>
> Out of interest.....has anyone ever attempted a snap in an airliner???
>
> I have heard of a captain doing a slow roll in a 747....but a snap? Is
> it possible?? What does a simulator do when pushed to such limits ( I
> know a simulator cant snap BTW...well, I assume any way LOL!!)
>
> Tom
>
> -----Original Message-----
> From: nsrca-discussion-bounces at lists.nsrca.org
> [mailto:nsrca-discussion-bounces at lists.nsrca.org] On Behalf Of John
> Gayer
> Sent: Tuesday, 1 July 2008 11:42 AM
> To: General pattern discussion
> Subject: Re: [NSRCA-discussion] Snap Entry
>
> Actually a snap can occur without any aileron input...but I challenge
> anyone to show a pattern ship doing a snap roll on a 45 degree downline
> without ailerons.
>
> The approach snap can occur with only the use of elevator and it
> involves one wing panel stalling before the other. Try an approach with
> crossed controls(aileron/rudder with some power. pull the nose up
> gradually and see which wing drops. It will be the wing with the aileron
> trailing edge down. This is contrary to what we see in a pattern snap
> roll which always snaps in the direction of the aileron deflection thus
> indicating the lack of any stalled condition
>
> John
>
> seefo at san.rr.com wrote:
>
>>Just to stir the pot a little further..
>>
>>I'm not sure a contemporary pattern plane can generate enough pitch
> rate to reach critical angle of attack and properly perform a snap roll.
> I think it's far more likely that we're seeing nothing but a heavily
> yawed aileron roll, with the pitch break only being shown to judges to
> convince them there is actually a stall happening, when in fact there is
> not.
>>
>>If a snap cannot occur using ONLY elevator and rudder, then the wing is
> not stalling. Aileron inputs into a snap actually inhibit flow
> separation, as the inboard wing angle of attack is drastically reduced,
> and the outboard wing AoA is drastically increased.
>>
>>But since there is no way to actually determine what is happening
> aerodynamically on an F3A airplane, the best a pilot can do is fly the
> airplane to what the judges expect to see based upon the rules. It
> really doesn't matter what the control inputs are if the airplane LOOKS
> like it's doing the right maneuver.
>>_______________________________________________
>>NSRCA-discussion mailing list
>>NSRCA-discussion at lists.nsrca.org
>>http://lists.nsrca.org/mailman/listinfo/nsrca-discussion
>>
>>
>>
> _______________________________________________
> NSRCA-discussion mailing list
> NSRCA-discussion at lists.nsrca.org
> http://lists.nsrca.org/mailman/listinfo/nsrca-discussion
> _______________________________________________
> NSRCA-discussion mailing list
> NSRCA-discussion at lists.nsrca.org
> http://lists.nsrca.org/mailman/listinfo/nsrca-discussion
>