vortex generators versus Horton Stol kit

MickP170A · Post by **MickP170A** » Mon Apr 26, 2010 1:41 pm

Hi,

Can anyone advise the difference in performance of vortex generators versus Horton Stol kit on a 170A ?
What are pro's and con's of either ?

How much difference do either of them really make ?

Post by **Bruce Fenstermacher** » Mon Apr 26, 2010 3:55 pm

Mick,

Welcome to the forum and 170A ownership. buy now I'm sure your realized the wealth of information available here and of course virtually any question asked gets answered with both fact and opinion.

Lots and lots of things have been discussed and already available here with a search. In this case searching on the word vortex will find at least the following threads which might answer your questions and perhaps create more.

http://www.cessna170.org/forums/viewtop ... lit=vortex
http://www.cessna170.org/forums/viewtop ... lit=vortex
http://www.cessna170.org/forums/viewtop ... lit=vortex
http://www.cessna170.org/forums/viewtop ... lit=vortex
http://www.cessna170.org/forums/viewtop ... lit=vortex

After reading these threads ask away. But in a nut shell, yes STOL kits and VGs work, and they apparently work together, they are not for everyone. I liked my VGs on my first airplane which essentially was a B model. If I won them as a door prize like I did the first set I'd install them on my current A model (with permission of my partner of course). But I don't plan to buy them for my current A model because even though I'm operation out of an 1800ft grass oneway strip at sea level, I don't need them. I've got lots of other things to buy.

N2255D · Post by **N2255D** » Mon Apr 26, 2010 4:30 pm

Re: vortex generators versus Horton Stol kit
Post by N9149A Â» Mon Apr 26, 2010 11:55 am

But I don't plan to buy them for my current A model because even though I'm operation out of an 1800ft grass oneway strip at sea level, I don't need them. I've got lots of other things to buy.

Bruce,That's a little bit different than UKT isn't it.

Post by **Bruce Fenstermacher** » Mon Apr 26, 2010 9:03 pm

Yes Walt. My new 170A is based at a private strip just off the downwind to base turn of UKT Rwy 29. It is one way mainly because of the slope in one direction but this is all another topic.

MickP170A · Post by **MickP170A** » Tue Apr 27, 2010 3:24 am

Thanks, will have a good read and see what i come up with.

Regards,

Mick Poole

futr_alaskaflyer · Post by **futr_alaskaflyer** » Tue Apr 27, 2010 8:30 pm

I'll save you the read about VGs:

I. Opinion of 170 owners who don't have them on a 170 nor ever have: "They don't work, or if they do, it makes marginal difference."

II. Opinion of 170 owners who currently do have them or have flown more than just a couple flights with them installed: "They work, they make some difference in certain situations, but I wouldn't consider them a high priority."

This is, of course, in contrast to certain other airplane makes, where the advantage is less in doubt.

By the way I am in the second category, above.

MickP170A · Post by **MickP170A** » Wed Apr 28, 2010 5:44 am

Thanks for the input, It is as I had anticipated, Will spend the money elsewhere and on other priorities first.

Cheers,
Mick Poole from Down Under....

Post by **GAHorn** » Wed Apr 28, 2010 4:16 pm

futr_alaskaflyer wrote:I'll save you the read about VGs:

I. Opinion of 170 owners who don't have them on a 170 nor ever have: "They don't work, or if they do, it makes marginal difference."

II. Opinion of 170 owners who currently do have them or have flown more than just a couple flights with them installed: "They work, they make some difference in certain situations, but I wouldn't consider them a high priority."

This is, of course, in contrast to certain other airplane makes, where the advantage is less in doubt.

By the way I am in the second category, above.

There is yet another category: "170 owner who doesn't have them, but has flown 170's with them, and consider them marginal and overrated." I am in that category, which only partially explains why I don't have them.

cmsusllc · Post by **cmsusllc** » Thu Apr 29, 2010 3:05 am

Yea but you flat landers have rust on the last third of your throttel control too so you wouldn't know what to do with any extra lift.
Scott ..... 53B

MickP170A · Post by **MickP170A** » Thu Apr 29, 2010 12:24 pm

ok got the general idea about the vortex generators, what about the Horton STOL kit ?

170C · Post by **170C** » Thu Apr 29, 2010 10:38 pm

What a can of worms this subject can be

As a 56 172 owner with a Horton STOL installed, I will tell you that I firmly belive the drooped leading edge will add some weight to your plane (don't know how much exactly) and based on my experience and that of a number of other folks, I believe it will cost you a bit in cruise speed. (Now George, I realize I am referring to a GREEN plane, but I think it applies to Red ones too

). I do believe the stall fences and aileron gap seals MAY give some additional control in very slow flight. Whether that is worth the weight & speed loss penalty or not would be your decision. Others may have different views on the Horton. I don't currently have the flap gap seals so don't know if that would be a + or -. My IA keeps telling me I should put them on. He has them on his '59 C-182, but I haven't seen enough data/opinions, etc for or against them to make that decision. Let us know what you decide and what the results are.

Thu Apr 29, 2010 11:26 pm

Mick the first question you have to answer really is this. What do you plane to do with your 170? If you are going to operate out of 2000 ft strips and larger at or near sea level you don't need any changes, VG or Stol kit to the 170.

If you are going to operate out of smaller strips over obstacles you might enjoy VGs or a Stol kit on your wing. VGs will give you more margin so will the Stol kit. VGs are cheaper, easier to install and much more reversible. A Stol kit cost more is harder to install and practically irreversible.

jrenwick · Post by **jrenwick** » Fri Apr 30, 2010 1:06 am

My current 170B has the Horton STOL kit (my first one was stock). I don't know how much weight it added when installed (I bought the airplane long after). I know that it lowers the stall speed, but I don't know by how much. I land at 55 over the fence, and that seems like plenty of speed. It shortens the ground roll on both takeoff and landing, but I don't know by how much. I can consistently outclimb a stock 170B. It changes the landing characteristics considerably, because the wing will still want to fly from the 3-point attitude if you land too fast (I have 800x6" tires, which raises the AoA a little bit). I've learned to make all landings with full flaps to lower the landing speed and decelerate quickly once on the ground.

That's about it for the Horton STOL kit as far as I know. You decide if you want all that, and what it's worth to you.

Best Regards,

John