You are right Alex. A/C don't have needs. They simply respond to the laws of physics. Pilots have needs. (We'll stick to the aeronautical needs only for this discussion.) If you read the post you were referring to in those terms, it will make more sense.
Wings need 2 things to generate lift, and they need them both. A/S and AOA. Yes, a flat bottom curved on top wing will generate enough lift from Bernoullies alone to register on a sensitive scale, but not enough to be useful. In general, wings need both A/S and AOA.
Wings pull us to the inside of the turn because lift is being created in that direction (see previous posts on that subject ad nauseam), not because the inside wing is being dragged backwards by drag. In fact, it's the outside wing with the down aileron at the beginning of the roll that has the increase in induced drag and gets dragged backwards and turns us opposite our direction of desired turn initially unless we use rudder to coordinate the roll into the turn.
Your final paragraph about the lowered and raised ailerons is either totally incorrect or is simply worded in a way you didn't mean, because the drag you talk about is actually backwards.
Jim Bair
From: A. Censor
Sent: Saturday, March 17, 2012 12:13 AM
Subject: Light-Sport Aircraft Yahoo group Re: Why does it TURN (not just slide sidewards) when you bank w/ no
Hi R.
I don't understand your explanation.
I don't get that the aircraft "needs" to generate more lift.
Aircraft are not conscious and don't "need" or care about anything.
And even if the nose somehow drops of it's own violation or something I missed understanding I don't see how the dropping nose would do anything other than cause increase of airspeed and/or loss of altitude. Why should it cause a turn? I drop the nose all the time on descents and it never causes a turn.
So we'd have an aircraft sliding toward the side banked but – unless there's something causing a rotation of the fuselage around the vertical axis still no turn.
I stand by my theory for now:
> Somehow the bank must be creating more drag on the lower wing (or less
> on the raised wing) creating the turning force.
>
> My guess is the raised aileron on the lower wing -- being in the
> different airflow of the upper wing surface -- creates MORE drag on
> the lower wing than the lowered aileron on the raised wing does.
> on the raised wing) creating the turning force.
>
> My guess is the raised aileron on the lower wing -- being in the
> different airflow of the upper wing surface -- creates MORE drag on
> the lower wing than the lowered aileron on the raised wing does.
Alex
Re: Why does it TURN (not just slide sideward) when you bank w/ no
Posted by: "Richard Williams" rkwill@lewiscounty.com rkwill98356
Thu Mar 15, 2012 10:01 am (PDT)
circicirci,
The airplane needs to generate more lift,
It will try to generate the more lift by dropping the nose to speedup.
The dropping nose slides sideways along the angle of bank.
result... the airplane turns (and loses altitude).
R. Williams
---------- Original Message -----------
From: "circicirci" <acensor@fastmail.
To: Sport_Aircraft@
Sent: Thu, 15 Mar 2012 15:53:46 -0000
Subject: Light-Sport Aircraft Yahoo group Why does it TURN (not just slide
sidewards) when you bank w/ no rudder?
> Hey Bill,
>
> Thanks for that question. I'd been thinking about that.
>
> To recap your question (which is below):
> In level flight without any rudder you bank. The plane turns to the
> side of the bank. The horizontal component of lift should slide the
> plane sidewards towards the side you have banked but continue to fly
> straight ahead but banked. It does not explain what makes the plane
> turn on a circular course. So what's making the plane TURN?
>
> Gary, I don't see how dihedral explains the plane _turning_ toward the
> side of the bank. All postive dihedral does is create a tendency for
> the plane to return to level flight if you let go of the controls.
> Negative creates a tendency for the plane to continue to roll further
> once you start a bank.
>
> Somehow the bank must be creating more drag on the lower wing (or less
> on the raised wing) creating the turning force.
>
> My guess is the raised aileron on the lower wing -- being in the
> different airflow of the upper wing surface -- creates MORE drag on
> the lower wing than the lowered aileron on the raised wing does.
>
> Alex
__._,_.___
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