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ACRO E-mail Archive Thread: [Acro] RE: 1D drivers - Spin help

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ACRO E-mail Archive Thread: [Acro] RE: 1D drivers - Spin help



                


Thread: [Acro] RE: 1D drivers - Spin help

Message: [Acro] RE: 1D drivers - Spin help

Follow-Up To: ACRO Email list (for List Members only)

From: "Randy Owens" <zippyx at sprynet.com>

Date: Fri, 12 Jul 2002 18:05:21 UTC


Message:

I don't fly a 1D, but I've found if my entry speed is too low into a
spin, I'll get the same results you've described.  I was out playing
around with spins on a few occasions (different entries, speeds, etc.).
I fly a CAP-10B and found it and the Decathlon I initially trained with
both behave this way.  
 
I don't know how helpful this might be, but just a thought.
 
-Randy

-----Original Message-----
From: Peter Ashwood-Smith [mailto:petera at nortelnetworks.com] 
Sent: Friday, July 12, 2002 10:37 AM
To: 'bob at scherer.name'; IAC List
Subject: [Acro] RE: 1D drivers - Spin help




	Tried accelerating the pull at the end, leading with rudder,
lagging with rudder.   Just can't get it to break and rotate.

	It generally takes  to 1 turn to then really spin, and then
recovery is all over the compass. (Only have another  to  to go -
Sportsman)

There are several possibilities. 

- You have a technique problem of some kind. Most likely you are not
really giving full back stick, or are relaxing it without knowing.
Sometimes the stick will not go all the way aft because of your seating
position, size of your backpack chute etc. so make sure you are really
getting full aft stick with you+chute in the plane. You may not "really"
be giving full rudder either. Also, you may be aileroning into the spin
a bit. This could cause problems with such big ailerons since it will
lower the AOA of the inboard wing and delay its stall and you'll get a
spiral instead. Watch your ailerons and make sure they are perfectly in
trail before you enter the spin. If you airspeed is increasing in the
spin you are for sure spiraling.

- C of G is too far forward. First thing I'd do is a careful weight and
balance and  make sure your C of G is where Dan Rihn says it should be.
I'm guessing the C of G shifts aft as fuel burns off so try acro with a
bit less fuel and see if your spins improve. Do NOT do anything to shift
your C of G aft without checking your W&B very carefully and talking to
the designer etc. An aft C of G can result in impossible spin recovery
so take this comment with HUGE amounts of caution.

- Check your elevator travel and rudder travel and make they are exactly
what they are supposed to be. Its possible you are a bit shy on
rudder/elevator throws.

- Check the stab incidence and make sure it is per plans as this can
reduce your elevator effectiveness. Are you flying with lots trim ? 


   Anyway be REALLY careful not to change the plane or its W&B without
knowing what you are doing. We don't need another stall spin accident.

   Peter 

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