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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: "Peter Ashwood-Smith" <petera at>

Date: Fri, 12 Jul 2002 17:42:00 UTC


	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 -

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.

Attachement 1: part2.html


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