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My Aquilla keeps pulling left with new fairing

Posted: Sat Jan 09, 2010 12:42 pm
by Asterix
Eish! a bit of disappointment going on here - just before the holidays I fitted a fairing to my Aquilla and flew it down to my parents farm for the holidays. Weather was calm, but I got the distinct impression that the trike was pulling to the left the whole time. Subsequently I removed the fairing and ofset the pin on the front of the bowsprit to the right to try and compensate. Also loosened the surface around the washout tube on the right wing (Aquiila II). The problem is not as bad now, but still, when pulling the bar and building airspeed, the trike still vears to the left and the left wing wants to dip.

Has anybody had the same type of problem? Any advice on how to fix it? I like flying with the fairing but will take it of if I can't get my plane to fly straight in no-wind conditions. ##

Re: My Aquilla keeps pulling left with new fairing

Posted: Sat Jan 09, 2010 1:18 pm
by gertcoetzee
Yes, the fairing is like a huge rudder. I think it emphasize the "adverse jaw" - sometimes I fly with my front wheel turned in the opposite side to fly straight.

Re: My Aquilla keeps pulling left with new fairing

Posted: Sat Jan 09, 2010 3:02 pm
by Cloud Warrior
I have read on the BMAA forum (if I remember correctly) that when P&M developed their first touring screens for their trikes, they found that even a very small change in the size and shape of the lexan could make a big change in handling characteristics of the trike concerned. Hence the long time it took to finalise the design before they were happy with it.

Unfortunately I think you are just going to have to fool around with the fairing until you get it sorted......

Re: My Aquilla keeps pulling left with new fairing

Posted: Sat Jan 09, 2010 6:09 pm
by skyrat
i have the same problem and funny enough i also compensate by steering the front wheel in the opposite direction. i also experience less pull the heavier we are. like when i have a pax ** **

Re: My Aquilla keeps pulling left with new fairing

Posted: Sat Jan 09, 2010 6:38 pm
by Asterix
Skyrat - Very true - with a pax the problem is almost non-existent! Been trying to phone the guys at Solo Wings for advice but I think they are still closed - perhaps somebody from Solo Wings should provide some help - I know of at least one other trike at Microland where the pilot complains about the same thing.

My Aquilla keeps pulling left with new fairing

Posted: Sun Jan 10, 2010 4:41 am
by John Young
Cloud Warrior wrote: ... when P&M developed their first touring screens for their trikes, they found that even a very small change in the size and shape of the lexan could make a big change in handling characteristics of the trike concerned. Hence the long time it took to finalise the design before they were happy with it...
Hi,

That's correct. P&M utilised a wind tunnel to help finalise the tuning and adjustments.

Asteriks - like the other posters, I have heard of a number of guys who off-set with their nose wheel. :wink:

Regards
John ZU-sEXY

Re: My Aquilla keeps pulling left with new fairing

Posted: Sun Jan 10, 2010 12:42 pm
by Biggles
gertcoetzee wrote:Yes, the fairing is like a huge rudder. I think it emphasize the "adverse jaw" - sometimes I fly with my front wheel turned in the opposite side to fly straight.
This makes sense. So if a wing has a natural slight yaw in straight and level flight due to a slighly bent batton or other differences the wing doesn't fly perfectly straight but you wont pick it up in normal flight. But with a fairing its like a slight crosswing on he side of the fairing causing the whole trike to bank.

So the remedy would be to get the wing to fly straight... check the wing is perfectly symetrical.

Re: My Aquilla keeps pulling left with new fairing

Posted: Sun Jan 10, 2010 5:01 pm
by Asterix
Hi Biggles - checked this out - without the fairing the trike flies perfectly straight - I'll just keep on fooling around with the fairing untill I resolve the problem - I have already ofset the nose to the right - this helped some - next step is to shift the right bracket slightly forward to induce more drag on the right side of the fairing - this might cut it - i will post my results. :?

Re: My Aquilla keeps pulling left with new fairing

Posted: Sun Jan 10, 2010 7:35 pm
by Biggles
Asteriks wrote:Hi Biggles - checked this out - without the fairing the trike flies perfectly straight -
as a matter of interest how did you check this? I have been wondering if mine is flying straight. Theoretically without a fairing it will still fly straight and level, even if the wing is crabing slighly...

What keeps the wings straight it equal drag on both sides of teh wing. If you have slightly more drag on one side you can get slight yaw

Re: My Aquilla keeps pulling left with new fairing

Posted: Mon Jan 11, 2010 2:17 pm
by Asterix
Biggles, you are correct about the yaw if the drag is not equal. With my fairing of and a slight northwesterly wind, I made a couple of runs over my windsock, directly into the wind along an imaginary line towards a target on the horison, and adjusted the wings around the washout tubes untill she flew straight into the wind, hands of, without dipping a wing.

About the drag on the fairing, I already ofset the pin on the front of the bowsprit which aligns the fairing to the right. This eased the problem a good deal. My next step will be to move the right bracket on the seatframe slightly forward in order to try and induce a bit of extra drag on the right side of the trike - hopefully this will sort it out. In the meantime I flew three hours this morning in conditions ranging from calm to fairly turbulent, and using the front wheel as a "rudder", surprisingly, also helped some. BUT - I WANT IT TO FLY STRAIGHT!! END OF STORY!! :twisted: so, I'll just keep on tinkering untill I get it right, unless someone can provide me with some more advice? :roll: