Vortex Generator position VG

[Dusty]

One vg's supplier (stolspeed?)has a testimonial section,a kf flyer tried staggered installation which he seems to think works.

[jiott]

Try the search function again. Quite a lot of stuff comes up if you use the words: VG's or vortex generators in the keyword box and search Titles only (advanced search function). This subject has been rolled around a lot.

[WurlyBird]

At the risk of being an ass, I followed your suggestion and searched "titles only" for "VG", "VG's", and "Vortex generators" and only two threads came up. One about what material to make some DIY ones out of and this one. I know VGs are discussed, A LOT, but I can not find much info about KF specific placement. Some people report miracles and other a waste of money, it comes down placement and having a collection of placement on each model and the results could be very useful. Maybe even helping fix issues with those reporting the wasted money.

[WurlyBird]

As an admission of inaccuracy, I had searched for "vortex generator". I went back and searched for "vortex generatorS" and four more threads popped up. Only one made mention of measurements and it was for only one model.

[Cosmofly]

Do try Stolspeed, they are Australian based. Very reasonably priced and the website shows quite a lot of data on tests that they conducted.
Good luck.

[tx_swordguy]

I fly an avid flyer with a heavy hauler wing so my mileage may vary. I bought my VGs from land shorter.com due to price more than anything. I placed them 10% back from the leading edge and spaced roughly 2" I believe. Not saying it is a miracle but I am definitely a believer. I will state my performance changes and let you judge whether it is worth it to you. For me it was. My stall went from 40ish to 37ish no noted change in top end. prior to VGs my landings when approaching the flair my wings would rock back and forth as they were losing lift ( at least that is what they felt like) Now the wings are rock steady all the way to the ground and it has given me much more confidence in slipping over the power lines to land on my 1000' grass runway. That in and of itself is why I am so in favor of them for no other reason. To me the stall difference is not a big enough change to worry about but it did change. I also put VG on the underside of my horizontal stab approx 1" apart not sure I really noticed much more pitch authority but I do get a warm and fuzzy feeling and would probably do that again anyway. As far as cleaning the wing to me just wipe front to back with a wet rag and I don't have problems cleaning. Hope this helps a bit
Mark

[WurlyBird]

Thank you for the feedback. I had not read the STOLspeed site. I like their information. Vortex-generators.com also has good descriptions as well as the best prices and an option for rectangular VGs like the ones BigJohn used on his KF that he reported on so well. I would like to go with landshorter.com just because they are the only one made in the US, but as is always the case they are not only the most expensive but you also need to supply your own adhesive and I like the idea of laser cut adhesive strips. But that is all brand stuff, which is not what this thread is about.

STOLspeed describes the location as being the highest point in the airfoil at a stall AOA. All other math aside, I want my plane to stall with the tail wheel in contact with the ground and the mains just off. So the VGs should be just forward of the highest point as the plane sits in parking, right? Is there a flaw with this conclusion I'm not seeing? Can anyone verify with their plane if placement works out like this?