Change in performance with different wing tips

A place to relax and discuss flying topics.

Moderators: GAHorn, Karl Towle, Bruce Fenstermacher

Post Reply
User avatar
ghostflyer
Posts: 1390
Joined: Mon Apr 21, 2008 3:06 am

Change in performance with different wing tips

Post by ghostflyer »

I have been given a set of wing tips off a late model Cessna 172 with the Hornier type shape. So has any body noticed any performance difference when they have been fitted to a 170A.
User avatar
edbooth
Posts: 498
Joined: Wed Nov 24, 2004 3:03 am

Re: Change in performance with different wing tips

Post by edbooth »

Years ago, a California member experimented with droop wing tips. First tried them installed regular, then reversed them with the tips up then tried them with one up and the other down....said could not tell much difference.....that's his story and was sticking to it. :?
Ed Booth, 170-B and RV-7 Driver
User avatar
ghostflyer
Posts: 1390
Joined: Mon Apr 21, 2008 3:06 am

Re: Change in performance with different wing tips

Post by ghostflyer »

Thank you for that reply , I had a good laugh when imagining that with the tips up and down . Many years ago I used to fly a Cessna 172 with these massive droopy tips and found landing exciting . It used to stall very suddenly and the aircraft would just drop down but at a very low speed . These tips on this aircraft used to droop about 8 ins down . Plus cross wind landings were a lot of fun also . You really had to work the rudders even more than a tail dragger. I was curious that if the late madel wing tips were fitted to a 170 series would there be a fuel saving . Iegally it can be done .
User avatar
canav8
Posts: 1006
Joined: Thu Sep 25, 2008 2:34 pm

Re: Change in performance with different wing tips

Post by canav8 »

Wing Tip performance can only be measured in the low speed regime. It is negligible in cruise settings. It will assist in lift from spilling off the wing in high angles of attack and slower speeds. It will increase aileron authority to a slower speed.
52' C-170B N2713D Ser #25255
Doug
User avatar
MoonlightVFR
Posts: 624
Joined: Sun Jan 02, 2005 5:55 pm

Re: Change in performance with different wing tips

Post by MoonlightVFR »

Wing Tip technology still being patented in 2014 +

Original patents same subject 1897.

Hornier papers dated 1950's

Winglet and Wingfence popular references.

Benefits to single engine aircraft limited claims, slow speed control ability, landing. Take offs.

Major benefit apparently in large aircraft cruising speed. Fuel savings. Save 2% ?? Difficult to measure improvements at less than 400 mph. Watch their math.
gradyb, '54 B N2890C
User avatar
Bruce Fenstermacher
Posts: 10313
Joined: Tue Apr 23, 2002 11:24 am

Re: Change in performance with different wing tips

Post by Bruce Fenstermacher »

Once again everything is relative. If you compare a slight improvement to an already good design, the change is insignificant. However make seemingly the same simple change to a the very worst design and the improvement is more dramatic.

Changing out the tip of a more modern airplane which has already had some design considerations applied will not result in much change. However when one finds that the symmetrical rounded wing tip design of the 50s 170 and even early Piper Cherokee is the absolute worst design, any change, including sawing the tip of square is a noticable improvement. What's noticable? Depends on the person. In many cases it is nothing more than the belief it is better and therefor it is. If one does not believe they can accomplish something because they are being held back mechanically, they are likely never to be successful.

If I had the wing tips and I wanted to use every advantage I could to push an envelope, I'd install them and never look back. Chances are pretty good you will feel they made some positive difference. On the other hand it is subjective whether any price payed for the improvement could ever be recouped unless that slight edge keeps you out of the trees, or in the case of the airlines a 1% improvement over the airframes life saves millions in fuel.
CAUTION - My forum posts may be worth what you paid for them!

Bruce Fenstermacher, Past President, TIC170A
Email: brucefenster at gmail.com
User avatar
canav8
Posts: 1006
Joined: Thu Sep 25, 2008 2:34 pm

Re: Change in performance with different wing tips

Post by canav8 »

MoonlightVFR wrote:Wing Tip technology still being patented in 2014 +

Original patents same subject 1897.

Hornier papers dated 1950's

Winglet and Wingfence popular references.

Benefits to single engine aircraft limited claims, slow speed control ability, landing. Take offs.

Major benefit apparently in large aircraft cruising speed. Fuel savings. Save 2% ?? Difficult to measure improvements at less than 400 mph. Watch their math.
Improvements to large aircraft fuel efficiency are totally debateable.

The reason why they are commonplace now is because when configuring for landing, a lower flap setting is required thereby using less power/fuel on approach. Airlines are encouraging an optimum flap setting on leased airplanes because they dont care about aircraft ownership. they care about how much fuel is burned. My company likes to encourage landing with flaps 15 on a 10K runway rather 30 or 40 for fuel savings. Its the truth! Personal aircraft owners are not as concerned about fuel burn on approach as much as replacing tires or aircraft wear and tear.
52' C-170B N2713D Ser #25255
Doug
bagarre
Posts: 2615
Joined: Thu Sep 30, 2010 11:35 pm

Re: Change in performance with different wing tips

Post by bagarre »

It reminds me of the kids putting wing kits on the backs of their Honda Civics to improve performance.
User avatar
ghostflyer
Posts: 1390
Joined: Mon Apr 21, 2008 3:06 am

Re: Change in performance with different wing tips

Post by ghostflyer »

You HAD to put a wing kit on a Honda to make it go. Other wise a bicycle would pass it .
User avatar
GAHorn
Posts: 20967
Joined: Fri Apr 12, 2002 8:45 pm

Re: Change in performance with different wing tips

Post by GAHorn »

Wooden clothes-pins holding playing-cards in the spokes DEFINITELY helped my Schwinn Tornado win neighborhood races! :P
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons. ;)
Post Reply