lml@lancaironline.net Mailing List Archive

BILL

here is the link for the VGs

http://www.pnwaero.com/Lancair.htm

i will be out of the country for a couple of weeks so the earliest for photos will be beginning of July

i put my VGs at 10% of chord; we tried 8% at the aileron which did not make a difference.

someone mentioned putting them just in the area of the ailerons; to produce better stall conditions; don't know about that

peter

Date: Thu, 30 May 2013 09:06:46 -0700
From: billhogarty@gmail.com
To: lml@lancaironline.net; peterpawaviation@hotmail.com
Subject: [LML] Re: Lancair Aerobatics

Peter:

First I've heard of VG installed on a IV-P. Can you give us some details on source. Details on the installation and mabe a photo.

Thanks,Bill Hogarty

On Thu, May 30, 2013 at 5:20 AM, PETER WILLIAMS <peterpawaviation@hotmail.com> wrote:

hi there
Boeing built several LNC4, but they enlarged the horizontal surface and redesigned the airfoil
maybe they have some expertise in aircraft design
Installed an AOA in my 4P and still learning it. Installed VG on the 4P and had a 7-8 knot reduction in stall speed; highly recommend it to everyone. rediculoudly cheap. $289.00 with a template and shipping.

peter

To: lml@lancaironline.net
Date: Wed, 29 May 2013 12:29:35 -0400
From: cwfmd@yahoo.com
Subject: [LML] Re: Lancair Aerobatics

Does anyone expect my mention of
'How about watching your AOAs! to avoid stall-departures (and subsequent) spins. ??

Good Point Terrence, I accidentally left that out, focusing on the SD instead...
I don't like to fly a Lancair unless it has AOA installed. But I'm an old Navy test Pilot. Good comments both about AOA awareness(orientation?) and control authority. I suspect the IV-P reduced control authority, to paraphrase Bert, in the tail, "there is not enough" surface.
We have an integrated systems project in our university course, speculating on how we could "fix" the IV-P. Suppose you had a fly by wire control interface. Could the mishap scenarios be over come by limiting certain control inputs? For example commanding too much angle of attack might limit back stick range or even add power and optimal climb if low altitude?
What if instant antispin control override kicks in, like the stick pusher in the F-104 or the Eclipse? What might the tradeoff be in aerodynamic improvements vs fly by wire? The problem is flight testing, because the fleet is not large enough to support this development and testing.
We used to attack the identified problem, such as the F-14 flat spin(see TopGun movie) or the SD issue in the F-16 "lawn dart" , as follows:
1. Identify the problem,
2. educate the pilots,
3. modify the training (I bagged lots of T-2 flt time, as a SPin/OutaControl flt instructor),
4. modify the software or display/control etc, but only lastly ,
5.modify the hardware changing the airframe.
These are, in sequence of expenses, which increase(exponentially), with each level. With the Lancair, we are always in the first 2 or 3 levels, because of funding, it is hard to reach farther. The greatest challenge is to reach those new Lancair enthusiasts, who have not yet been introduced to 1, 2 , & 3 !