Hey everyone,

I'm looking for an education on what you all know about Bush STOL kits. An aircraft I am looking at is equipped with one. It is not a 150 series, so the AD doesn't apply. Apparently there were some problems with it affecting the stall characteristics due to improper wing fence heights. So...any issues with other models? For those that have flown them, likes? Dislikes? Any info you can share would be appreciated.

Thanks,
Cory

Lowrider had a Bush STOL kit on his yellow 180. Seemed to like it. I may be wrong here but I think that Bush was pre Horton and the same but not certain. MTV may chime in here as I bet he will know.

AKT

aktahoe1 wrote:Lowrider had a Bush STOL kit on his yellow 180. Seemed to like it. I may be wrong here but I think that Bush was pre Horton and the same but not certain. MTV may chime in here as I bet he will know.

AKT

Does that Bush STOL kit have the leading edge cuff also?

Bush STOL is out of same metal building as Horton ,Owl, Mid-Amercia, aka Wellington ,Kansas . I've had them all but now only use on my airplanes the Sportsman STOL kit .

I did have the Bush STOL on the 180. I am not a very scientific person so I don't have any numbers for you. All I know is that at 6000ft lightly loaded 500ft of runway was more than enough coming and going. I have only flown two 180s Mine and Akts . Not much help for you . Never heard anything bad about bush.

I've flown a Bush STOL kit on a Cherokee Six-260 and like it.

The Bush kit has a similar/same cambered cuff as the Owl, MASA, etc. it is a lot smaller cuff than the Sportsman, and the performance improvement is noticeably less than a Sportsman equipped airplane.

I wouldn't be afraid of an airplane already equipped with a Bush leg edge, but I sure wouldn't install one. The Sportsman takes the same labor to install and as Bill suggests,is a much better kit, performance-wise.

MTV

Since the airplane is already so-equipped, it might not ever be a factor, but.... I believe that the Bush STOL kits are/were sold by the same outfit in Udall Kansas that sold the Avcom engine conversions. The owner is well-known for not being user-friendly. Good luck if you were to ever need replacement cuff parts, etc.

Thanks all. I passed on the plane with the Bush STOL. I appreciate the input though!

It's not hard to spot a wing modified with a STOL leading edge cuff, the tip-off that it's a Sportsman is that there are no stall fences on top. What is their purpose on the other kits, and why doesn't the Sportsman use them?

I can't speak as to why the Sportsman doesn't have them, but my understanding of the wing fence is to redirect the outward flow of air rearward, producing more lift. I'm sure someone else here can give you a much more detailed answer.

Maybe the added surface area of the Sportsman more than makes up for it.

Ive been told that fences also help keep the air moving straight back over the wing root, keeping the stall at the root of the wing to help keep aileron control at low speeds. but I also have been very curious why sportsman doesn't use them...
Now that I saw pictures of Kevin's 180, I see he still has fences on his, with the sportsman. I wonder if they make enough difference to leave them on if switching from a horton?

Just by looking at a wing that has stall fences on them from the rear you can see that the fences help direct the airflow not only over the aileron but helps keep the airflow from spilling into the low pressure area over the flaps. More aileron authority and making the flaps more effective for the job they are designed for.

Fences are intended to delay the propagation of the stall outward, thus affording greater aileron effectiveness deeper into the stall.

MTV

hotrod150 wrote:It's not hard to spot a wing modified with a STOL leading edge cuff, the tip-off that it's a Sportsman is that there are no stall fences on top. What is their purpose on the other kits, and why doesn't the Sportsman use them?

I've heard that the developer of the sportsman stol kit looked into stol fences and couldn't tell any difference so decided not to add them to the kit. Also I know of a few sportsman equipped aircraft that have stol fences. The planes started out with a Horton or other similar kit with stol fences then replaced the leading edge with the sportsman but left the fences.

I dont know if this is helpful to the discussion or not. This is on a C170.

mtv wrote:Fences are intended to delay the propagation of the stall outward, thus affording greater aileron effectiveness deeper into the stall. MTV

Kinda the way I heard it too- they keep the interupted airflow from moving out to the outboard (aileron) area of the wing.
Seems to me that a Sportsman cuff with fences would not be in accordance with the Sportsman STC, and a horton (or whoever) kit with fences but a replacement Sportsman cuff wouldn't be in accordance with either STC. Just saying.

xcalibursword wrote:I dont know if this is helpful to the discussion or not. This is on a C170.

It's helpful to me. I wondered how the cuff went on.

Apparently the Williams(Udall, KS) have a hard time answering the phone, are about to or have lost their PMA authorization according to the Denver, feds., so be careful about doing anything that might need support from them in the future. It is a shame they don't give the business to a child of theirs, of just sell it rather than give poor service.

I was hearing about their reputation for poor customer service years ago.