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I had an interesting conversation today with Micro AeroDynamics today concerning the Flight design fleet. Not too long ago they were starting to develop and test vg's for the Flight Design . They determined that some flight parameters could be changed to provide better performance. They contacted Flight Design (Germany) in order to discuss approval for vg's after all the flight tests had been completed. The response was that Micro AeroDynamics would have to give them all proprietary test data, drawings, engineering data, etc. Because of this the project was dropped.  Apparently Flight Design could then take all the data and develop their own vg project. This is what China does.

Too bad, the CT is a great plane but Germany is a real PITA to deal with. Thats why I went ELSA.

 

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Why doesn't Micro Aerodynamics offer the kit themselves in the aftermarket?   I think it boils down to risk.  If you were to approve a modification, you take on the risk and responsibility of that change.  Wouldn't you want to see all their test data, analysis, and drawings to make sure things were done correctly or would you just take someone's word for it? 

If something happened and the lawyers blamed the VGs for the crash what would Flight Design say to the aviation authorities when they asked for their analysis and data for the design change?  Would they say "Go ask Micro Aerodynamics for it"?  There are ways to get paid for their effort without worrying about Flight Design ripping them off.

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Micro AeroDynamics developes and sells a finished product and assumes the liabilities just like any aftermarket aviation company.  Try asking Rotax for their engineering data and drawings, it costs a lot of money to develop the R&D. I used to do this. This is no different than buying a vg system for a 310,or Baron or 172.

Micro AeroDynamics president/owner/test pilot is willing to work with me to develop a vg system for my CT if I choose to do so. 

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10 hours ago, Madhatter said:

This is the problem with SLSA, you can't do anything without the manufacturers ok. No STC's, no field approvals, no DER's. They hold you hostage to their prices and no aftermarket parts. ELSA is the only way to get anything done.

I mostly agree, but the FD folks (especially FD-USA) are a lot more accommodating than many manufacturers.  Try even getting an ADS-B install approved on a SportCruiser...

The sad fact is that that ELSA is a tiny portion of the fleet, and it's unlikely a company will develop a product that only caters to ELSA owners.  I'm hoping that whenever the FAA gets around to overhauling the LSA rules, a lot of these issues will go away, partially due to rule changes and partially because the current SLSA makers will have to compete for ownership with a wider range of new and existing aircraft (like the Cessna 152/172).

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The issue to get things approved through a MFG is the cost and regulations that they will have to sign off on. It could cost hundreds the easy stuff and many thousands of dollars for more complex. They have to certify that it is safe and works and then back it for the regulators.

FD has been very accommodating over the years and have tried to help people with mods, but you can't expect them to just eat the cost. Plus when you do a mod the Mfg is supposed to keep track of that and that's more time cost for employee's. There has to be give and take.

 

Sport Cruiser was in a league of their own for never helping people. Wouldn't even approve ADSB for their fleet. Now they're down the tubes and all of them will end up ELSA.. 

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According to Flight Design USA a lot more are going to ELSA. I believe as the fleet gets older and needs expensive replacement parts. experimental is the way to go. There are some manufacturers starting to anticipate this , I am working with one of them now. Some parts subject to routine replacement are as much as 1000% higher than they need to be, and some cheaply made.

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Roger, I don't disagree with you on that however beurocracy is a real problem in getting anything done in a reasonable time frame. I just installed dual Garmin G3X's, dual air data computers, G3X autopilot, and ADS-B. I doubt FD would entertain this at all. I am the only CT to ever install G3X with autopilot according to FD the G3X has been available for some time. There were a few small issues to work out. I have worked with FD in the past and got approval for an absolutely ridiculously simple change (one circuit breaker) and then got charged $150.

I don't have the patience for this nonsense. This also happens I certified as well but there are other avenues to get things done.

 

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I think ELSA is a win for owners *and* the manufacturer.  We get lower cost and ease of maintenance and upgrades, the manufacturer still gets to sell us parts but reduces their liability exposure.  Nobody really loses.

In slight defense of FD...they might need the engineering data for the VGs because even though as manufacturers they get to approve/disapprove modifications, they still have to comply with all the ASTM guidance regarding SLSA aircraft, which is like a telephone book in thickness.

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I think VG’s are a great idea on our planes. I wonder if anyone has done it and what the bottom end speeds are (or projected to be).

As a business person who has dealt with aviation related liability matters, and who has done business with German aero companies... I can understand why FD Corporate would be a roadblock.  Euro companies are notorious for paralysis through analysis.  

once FD approves a mod, they own it.  With that perspective, I don’t blame them.  They should get compensated for the implied risk of a 3rd party product that changes the plane’s flight characteristics.  And the owner is the one who gets sued by the injured and/or dead guy’s family(s).  FD’s insurers don’t like mods unless of course plane structural integrity is de-risked. Each mod is an occasion for the liability insurer to Add cost.  Freezing a design makes the OEM’s world an easier and cheaper place.

Re parts costs, all Aero OEMs make their “profit” on parts sales.  Selling planes and engines pays for the overhead.  That is why so many general aviation companies spend their long lives in and out of bankruptcy.  If they get into a cycle where planes sales and profitable parts sales can’t pay for the fixed overhead, they go bust.  And the short-lived ones shoot themselves early (Cessna LSA for ex).  

Alas, FD needs to charge high Part costs to pay for the business.  With their R&D costs (F2) and lack of new plane sales factored in... its high Part costs for years to come.

 

 

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PS: my company used to make parts for aero OEMs.  We sold one part for ex for $3,400. The OEM would turn around and sell it to the airlines for $18k.  One day, a plane landed with smoke in the cabin.  I remember thinking that I wouldn’t want to be that OEM for all the tea... the design (OEM) and manufacturing (us) were found to be sound.  To save money the airline sent the part out to be rebuilt.  The part is a consumable.  I’m sure the poor OEM spent a million or more on that investigation.  It’s not fun taking aero risk.

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Talked to Micro AeroDynamics again today and I have decided to go ahead with their offer of installing VG's with their help. They will provide data for initial vg installation and required flight test profiles .

I understand the cost issues with aviation companies as I used to do R&D for several. I also know the level of waste in some of these companies.

When the prices get too abusive companies go out of business or it opens the door for competition having better mouse traps. Just look at avionics companies over the years.

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fully agree using the VGs on a CT  

It's been done a South Africa and in France as well,,   maybe the members from France would know how to reach  that guy and ask him           ......see video below

he is based there :    https://sites.google.com/site/ulmpaimpolaise/nous-contacter

his is conclusion..he write that the plane much more stbale at lower speed and can maintain 35kts  in turbulence

 

I personnaly installed them on a different plane last summer (CH601hds )  and it changed the plane.

 

 

 

 

 

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I ordered VGs a while back and spoke with FD USA.  Cant remember the cost for approval but it honestly didn't seem unreasonable.   I just haven't gotten around to writing an email to follow up since I'm considering selling mine and moving to a bigger plane.

 

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I received approval from Flight Design USA for a bunch of changes on my SW:

Garmin 345

Ram Ball Mounts

USB Ports

Schroth Seatbelts

Landing Light

Earth-X Lithium Battery

JPI-450 Fuel computer

Tom and Arian have been fantastic to work with. Makes me very tempted to get an F2 or F4 someday.

 

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Most of my changes would probably never be approved. Nothing structural however some required a lot of research and fabrication. The different exhaust configurations have been the most difficult but some progress is being made. The vortex generators will require multiple vg locations as far as % of chord is concerned and a lot of flight tests according to Micro AeroDynamics until satisfactory performance is achieved. There is no data available for the CT airfoil vg locations according to them, it's trial and error to start with. Should be interesting and it keeps me off the street.

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One fellow put these on. 

see his posts fevlok@mmhs.co.za

CTSW Flight Design

 

I bought the VG's only for landing problems on the CTSW.  Coming from a Mooney 205 (1000h in 14 years) I really battle to land the CT smoothly (ctsw  2007)  it tends to drop out under me.


 I manage a good landing only by being widely awake and just as it drops add power
 Research shows that light sport and especially the CT has a higher than average landing accidents (just in  the CT defense no fatality's and is America's best seller in its class)

So I added the VG's as said before on the wing about 8% above and stabilator 10% back under surface.

Now I have the best greasers ever on all flap settings power-off landings
 15, 30, 40 degrees of flaps

Stalls were done mainly to see how she behaves, and she cling to the air like you know how.
 Full back stick she only start mushing and lose height,  nose just 'nods'
 Once at 40 degree flap, power burst, ball not totally centered, did drop a wing but gentle and easy to recover

So far I am much more than pleasantly surprise with the effect of the VG's. 
Must confess was skeptic but the price was right and worth a try.

 

Kiewiet
South Africa

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Any improvement to aerodynamics is a good thing and a reduction in stall speed is really good. I had put them on my 310 which put my vmc below stall, obviously important on a twin. I've had a j3 for many years and never saw a reason for vg's. But then I guess out of boredom I decided to put them on . What a major improvement they made in handling, and stall went from 39 to 23. I am curious to see what they will do on the CT and the vg's can be temporarily attached with double faced tape so as to remove them if neccessary. Right now work is being done to locate the optimal % chord location,  however there doesn't seem to be any data on the European C-180 airfoil available and I'm sure FD won't give it out. I suppose it will be trial and error, should be interesting. 

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