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I've posted the following message on the Matronics Zenith-List on 24 Aug 07:
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Boy, the mention of VGs sure does stir up a storm........ 
That’s really mystifying to me, because I’m just trying to share some really significant discoveries that we’ve found by experience..........
 
I’ve been in love with the CH701 for about 18 years, but intrigued by the possibility of removing the slats for most of that time, so always watching and studying for evidence in that direction.  I certainly didn’t start this as a manufacturer of VGs looking for a market for them on the 701.  I was a doubting sceptic before I actually tried them – and you wouldn’t think they’d do much on a wing like the 701, anyhow eh.  I was just going to remove the slats, as the Columbians had done, expecting to get better cruise efficiency, and prepared to lose some STOL capability which had lots to spare.  I expected maybe 10% improvement in fuel burn, but was amazed to find 23%!  STOL performance was less of course, but still adequate for most all practical use.  Then, being a curious experimenter, decided to try VGs, and was totally amazed that most all of the STOL capability came back!  The more I tried VGs the more I liked the effect that they gave, but I didn’t like the sharp points and the fit to the wing of the ones on the market.  And so designed and tested the ‘Feathers’, and so it went from there.......
 
I certainly didn’t start manufacturing VGs to make a lot of money.  Homebuilt aircraft is not a mass market and so many of those builders are complete sceptics, some are even from Missouri.....  And only need one set of VGs for an aircraft, then never hear from that one again.  If I wanted to make lots of cash flow I’d go for something like lawn mowing – get paid to do it all over again in a couple of weeks.  Or for more excitement, get a mobile dog-washing franchise....    I’m semi-retired, and not inspired to make any big business of this, just enough to keep tinkering and experimenting with light STOL aircraft.  There’ll be more to come, stay tuned.
 
Some of us are born experimenters and innovators, and are always interested in trying to make things go better.  (I even felt the need to modify my Buck pocket knife....)  Others just want to follow the straight and narrow, especially with aircraft – so let it be for them.  Surely we can all share this forum without animosity, and encourage the diversity rather than trying to shoot it down......  It’s almost as if it’s considered heresy to even explore alternatives......  This homebuilt aircraft game  attracts some really clever and capable minds, and I for one really enjoy sharing constructive ideas and experiences with them.    I’ve already met many really interesting and innovative builders online, and it’s just great to have this medium to hear from more of them all over the world.  The nay-sayers always seem to shout the loudest, but I know of many builder/flyers out there with heaps of good experience, who speak seldom, and quietly when they do, but are really worth listening to.....  It’s heartening to note that the first to be attracted to, and try these changes, were very experienced flyers, who now love their 701s even more since they’ve cut their slats off – surely that says something worth paying attention to.....
 
I pay most attention to real life experience and evidence, rather than theory or pre-conceived opinions.  And I’m ready to change my opinions when I see new evidence.  That ‘big wind tunnel in the sky’ is the real test.  That’s why I’ve flown 400 hrs in the last two years, always observing and testing these changes we’ve made.  And I certainly don’t fly like a Cessna - more like a hawk on a mouse!  Always looking for some new challenging spot to practice STOL landings.  Just got back from 38hrs of flying into outback Australia, actually using my STOL aircraft to land in very rough and remote places – how many of you really do land your STOL aircraft off-field....  Everything in that website is derived from such experience.
 
Lastly, there seems to be some misconception of the results I’ve claimed for replacing slats with VGs:
 
I’m not saying that VGs make for shorter landings than slats, just pretty close to equal STOL performance, with lots of improvement in climb, cruise and glide.  The common experience that most flyers notice is an gentler transition from hold-off to touch-down, thus making slower landings easier for the average flyer.
 
And I certainly don’t encourage anyone to go near Vne, but it sure is good to be able to cruise at 80 kts while burning less fuel than used to at 75, and still have pretty much the same STOL performance.  That’s really significant for those of us who actually go cross-country in our aircraft......
 
I’ve written pretty much all I have to say in the www.stolspeed.com  website, and written it as carefully and as completely as I can.  I won’t get into a shouting match here, as happens on so many forums.   But if there are serious questions that I haven’t covered in the website, I’ll discuss them.
 
Tailwinds always,
JG

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