Author Topic: Tip stalling  (Read 7822 times)

johnfireball

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Tip stalling
« on: November 03, 2011, 23:49:57 PM »
Hi all,
      Having problems flying my DG1000. I keep tipstalling it on final downwind turn to land. My Dad suggests that my turn is too flat and to put in loads of bank. He says the full size ASK6 was notorious for this and many were crashed on finals. Do models behave the same? Hopefully will try again on Saturday. Had some great flying last weekend at killakee with my phase, strongest winds I've yet flown in 30 knots +gusty, was great to learn to fly backwards and so easy to land. Course I broke it eventually but got a good hours flying.
John
I have the body of an 18 year old.........I keep it in the freezer

Happy Days

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Tip stalling
« Reply #1 on: November 04, 2011, 00:36:50 AM »
Hi there John.
I’d have thought it was unlikely that your DG1000 has the same airfoil as a full size ASK6 so there wouldn’t be much correlation between the two matters. And with all due respect to your dad, I think it would be a brave pilot who would put in a lot of bank while turning close to the ground

JP is really your man, as he has a DG1000.

If it’s always the same wing tip that stalls regardless of whether you’re turning left or right I’d suggest the plane isn’t laterally balanced. You might like to check that.

Other than that, the only suggestion I can think of is to maintain a higher air speed in the turn.

I’m very impressed with your flying in 30+ Knots. 8)

 John------A man after my own heart! :wink:

Keith
Try not to run out of airspeed, altitude and ideas....... all at the same time.

billscottni

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Tip stalling
« Reply #2 on: November 04, 2011, 08:10:14 AM »
From what I remember of JP's plane, it realy needs the speed kept up on it. Any time he tried to slow it up it tip stalled too.

I'm sure he'll chime in when he sees this thread

rogallo

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Tip stalling
« Reply #3 on: November 04, 2011, 08:27:30 AM »
Keep the nose down all the way. I see no reason not to apply plenty of bank if required just once the airspeed is maintained, ie more down!

Just my twopence worth.

Now I will hand you back to the theoretical nuts!

 :D  :D

R
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Tuff Choice.

JohnPearson

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Tip stalling
« Reply #4 on: November 04, 2011, 22:35:35 PM »
Hi John

Just read your problem, two things to think about,

1. I have flown your model and she was great in the air, however, I told you about the tailplane angle, if you have had a hard landing recently, it could be a little off, check it.

2. I think as rogallo mentioned, 'air speed' is the problem,when you fly down wind you will have plenty of speed, however, as soon as you turn into wind for landing, the model will tend to balloon on the downwind turn, and this DR1000 will drop her wing very quickly if you let the nose up near the stall point, so keep the nose down! My DR1000 was a pain in the arse for doing this.

3. Check the balance laterally as Keith suggests also for peace of mind.

See how you get on John and keep me updated how she flys

johnfireball

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Tip stalling
« Reply #5 on: November 04, 2011, 22:56:23 PM »
Hi John,
          Perhaps I'm making the turn too close to the deck (trying to plonk her down immediately after the turn). Maybe a higher approach would be better so allowing lots of down to be applied during the turn and then nudging her onto the deck. Lack of experience I guess.
Thanks John.
I have the body of an 18 year old.........I keep it in the freezer

erwan

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Tip stalling
« Reply #6 on: November 05, 2011, 09:46:21 AM »
Hello

I have many hours of real Ka6E and Ka6cr, it 's a very good glider, the stall speed is very low and it is no very easy to do a turn spin, in france no many crash with this glider, it is very easy to pilot, and no surprise with this.
La mouche qui pète ..

Brian

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Re: Tip stalling
« Reply #7 on: November 05, 2011, 12:43:31 PM »
Quote from: "johnfireball"
Hi all,
      Having problems flying my DG1000. I keep tipstalling it on final downwind turn to land. My Dad suggests that my turn is too flat and to put in loads of bank. He says the full size ASK6 was notorious for this and many were crashed on finals. Do models behave the same? Hopefully will try again on Saturday. Had some great flying last weekend at killakee with my phase, strongest winds I've yet flown in 30 knots +gusty, was great to learn to fly backwards and so easy to land. Course I broke it eventually but got a good hours flying.
John


Hi,
Where is your CG ??
Can you or do you use spoileron on landing ??

Brian
Serious Power

johnfireball

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Tip stalling
« Reply #8 on: November 05, 2011, 23:12:35 PM »
Hi Erwan,
            He claims it was the KA6e with laminar flow wings that showed this characteristic. Anyway the DG is still relatively in one piece so will try again with more bank when conditions permit.
John.
I have the body of an 18 year old.........I keep it in the freezer

woodstock

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Tip stalling
« Reply #9 on: November 06, 2011, 13:27:55 PM »
Good advice all round here!  

Any scale model of a high-aspect-ratio modern racing class sailplane will start getting tricky to fly as the wingspan gets much below 4 m.  The chord of these planes' wings are so narrow, there's hardly anything to keep the thing in the air!  In general then, they just don't do slow, or even slower :D !  I have seen a lot of similar comments in various fora about the 2.6 m - ish scale planes, a lot of people have got into trouble on the landing pattern, and it seems flying too slow is the main culprit...
Chris van Schoor

erwan

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Tip stalling
« Reply #10 on: November 06, 2011, 19:42:15 PM »
Hello

The Ka6E fly well like the Ka6 CR.  :wink:
La mouche qui pète ..

mat2verre

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Tip stalling
« Reply #11 on: November 08, 2011, 23:20:01 PM »
Following all advices written upper, just keep in mind that:

- Incidence (i.e angle between relative air flow and wing chord) must not vary during downwind phase: keep the nose down! - It is normal that your glider goes fast from the ground, but what's about her airspeed? Airspeed is the only reference to take into account...

- Because of downwind, your turn radius will be high at the beginning, and will decrease as much as the glider faces the wind... So don't hesitate to bank enough, at the beginning of your turn, to not let your glider go too far under the wind, otherwise she will hardly come back frontwind.

- And remember to always achieve your turns by using ailerons + rudder: you won't generate any slip or skid, which, added to a high incidence, could lead to a spin turn.

Here are a few advices that we give to full-size glider trainees...

A+

Mat
"Tu vois Bernard, toi et moi on a le même problème: on peut pas tout miser sur notre physique, surtout toi..."