Topics

Varieze Vortilons ..... Again ....


gilbert_drieux
 

De : Gilbert Drieux <gilbert.drieux@...>
Envoyé : lundi 4 mai 2020 18:57
À : canard-aviators@canardzone.groups.io <canard-aviators@canardzone.groups.io>
Objet : RE: [c-a] Varieze Modification Questions
 
Hi Mike, Hi gang,

Attached is a file related to VariEze' Vortilons .
As made for my VariEze.
Best regards.


Gilbert-Pierre DRIEUX

                 (_
|-------==(_)==--------|  VE  #1736.
             o/ | \o               F-PMPZ @ LFPK.

Such is life und es wird immer sucher.



De : canard-aviators@canardzone.groups.io <canard-aviators@canardzone.groups.io> de la part de nosedragger48154 <ezdriver@...>
Envoyé : lundi 4 mai 2020 15:25
À : canard-aviators@canardzone.groups.io <canard-aviators@canardzone.groups.io>
Objet : Re: [c-a] Varieze Modification Questions
 

Thanks Mike for the info.  I will be installing the “3” V’s and figure things out as I go.

 

Sincerely,

 

Mike Scovel

SE Michigan

VariEze

 

Mbl     (313) 608-7202

Email   ezdriver@...

Email   info@...

             http://www.brighterstick.com

 

 

 

From: canard-aviators@canardzone.groups.io <canard-aviators@canardzone.groups.io> On Behalf Of Mike Tooze via groups.io
Sent: Sunday, May 3, 2020 3:35 PM
To: canard-aviators@canardzone.groups.io
Subject: Re: [c-a] Varieze Modification Questions

 

Hi Mike,

You are correct, the vortilon plans show three per wing.

Three per wing is fine as when I transitioned from cuffs to (3/w) vortilons I had to reevaluate the way I few both t/o and landing, mainly landings.  Difficult to describe but compared to cuffs she flies-in rather that bombs-in.

 

However such was the difference in takeoff that I decided to add a further v per wing.  This I scaled up from the plan's sequence of three and placed it with respect to the stagnation point/line.  I placed each extra midway between the innermost v and the wing root/ strake joint.

I used sealant as it was only an experiment - but they are still there!

 

The up side is that a friend says that in a formation t/o with two-up I get off the ground sooner than he with only one-up.  But it's not apples for apples as he has an O-200 powered VE. 

(There is also the possibility that the airflow from the new, innermost, vortilon may help aileron effectiveness - uncertain as my ailerons are slightly longer than standard.)

 

The down side is the 'switch-off' when, after a t/o you might lower the nose to gain speed more quickly, the AoA is inadvertently reduced leading to the vortilon affect reducing hence loss of some lift.  Not good if in a shorter field t/o.  

Caution - With four vortilons this is accentuated.

 

As this is against the standard I have never publicized this before now but I know of at least one other who has tried similar. (Not counting Gene who it seems to have acquired his V-E with four fitted.)

 

In summary:  Definitely do fit the vortilons, three per wing as plans, do not fly without them.(Or the cuffs which the vortilons superseded very effectively)

Only after fully evaluating the full flight envelope and becoming fully familiar with your particular Vari Eze should you consider changing anything at all.

 

Best regards,

 

Mike T O-235 Vari Eze

Trying not to confuse, (or write too often ;^)

 

 

 

 

 

 

On Sunday, 3 May 2020, 19:26:16 BST, nosedragger48154 <ezdriver@...> wrote:

 

 

Gentlemen, I am about to install my newly mad Vortilons on my VariEze wing.  However everything I saw when building my Vortilons, stated to use 3, never saw anything that said 4.  Am I missing something?

 

Sincerely,

 

Mike Scovel

SE Michigan

VariEze

 

Mbl     (313) 608-7202

Email   ezdriver@...

Email   info@...

             http://www.brighterstick.com

 

 

 

From: canard-aviators@canardzone.groups.io <canard-aviators@canardzone.groups.io> On Behalf Of Mike Tooze via groups.io
Sent: Saturday, May 2, 2020 7:37 AM
To: canard-aviators@canardzone.groups.io
Subject: Re: [c-a] Varieze Modification Questions

 

I would not normally think of backing up a point of Ken but this is such a safety issue.  Whatever you do,Gene, ensure this new Vari Eze has the plans design vortilons.

If removing what you call a 'vortilon' made a 3mph difference then it is not a vortilon. Not the vortilon that we are recommending.

Please go back to the plans to re-check what you have against what you should have.  (I once saw a photo on [c-a] of a Rutan type with the vortilons mounted upside down, i.e. with the vorilons above the stagnation point. That would have a drag affect)

BTW Just for clarification.  My 720lb empty wt was the 1982 wt.  Much air has flown over the wings since then, example I'm minus the two Bendix mags (put those in your pocket to see the difference;-), the nav/com for a Terra760D then for a FUNKE 8.33.

Lastly check all the mails re wt&balance and trimming out, incl my contribution.

 

Above is not directed at Todd who welcome as doing a careful job in bringing his Vari Eze back into, I'm sure, good satisfying service.

 

Mike T

 

 

 

 

On Friday, 1 May 2020, 21:15:44 BST, KEN4ZZ via groupsio <ken4zz@...> wrote:

 

 

Do not, repeat, DO NOT remove your VariEze's vortilons unless you plan to retrofit wing cuffs, especially if you have a full electric O-235 = butt heavy. 

I flew my first several hundred hours slick winged, before Burt developed the cuffs - which I still have.  With a modestly aft, but within CG limits loading, the 'Saber Dance' divergent Dutch roll that was clearly spelled out in the original POH is indeed present.  I did a full exploration of the flight envelop - at altitude - during my phase one and at aft CG limit the aircraft would roll off after just a few cycles.  It almost certainly would not be survivable if it inadvertently happened in the pattern.  Cuffs or vortilons significantly reduce the Dutch roll to usually nothing but occasionally at most a mild, stable wing rock.

Ken

On 5/1/2020 1:05 PM, Gene via groups.io wrote:



 Plane came with vortilons, 4 per wing. I knocked one off (outboard starboard) flew it, picked up 3 MPH, re installed, lost the 3, knocked it back off and have flown 300 hours with the asymmetric 3 and 4 configuration. I'm considering removing all of them when I paint.


nosedragger48154
 

Thanks Gilbert!

 

Sincerely,

 

Mike Scovel

SE Michigan

VariEze

 

Mbl     (313) 608-7202

Email   ezdriver@...

Email   info@...

             http://www.brighterstick.com

 

 

 

From: canard-aviators@canardzone.groups.io <canard-aviators@canardzone.groups.io> On Behalf Of gilbert_drieux
Sent: Monday, May 18, 2020 1:13 AM
To: canard-aviators@canardzone.groups.io
Subject: Re: [c-a] Varieze Vortilons ..... Again ....

 

De : Gilbert Drieux <gilbert.drieux@...>
Envoyé : lundi 4 mai 2020 18:57
À : canard-aviators@canardzone.groups.io <canard-aviators@canardzone.groups.io>
Objet : RE: [c-a] Varieze Modification Questions

 

Hi Mike, Hi gang,

 

Attached is a file related to VariEze' Vortilons .
As made for my VariEze.

Best regards.

 

 

Gilbert-Pierre DRIEUX

 

                 (_

|-------==(_)==--------|  VE  #1736.
      
       o/ | \o               F-PMPZ @ LFPK.

 

Such is life und es wird immer sucher.

 


De : canard-aviators@canardzone.groups.io <canard-aviators@canardzone.groups.io> de la part de nosedragger48154 <ezdriver@...>
Envoyé : lundi 4 mai 2020 15:25
À : canard-aviators@canardzone.groups.io <canard-aviators@canardzone.groups.io>
Objet : Re: [c-a] Varieze Modification Questions

 

Thanks Mike for the info.  I will be installing the “3” V’s and figure things out as I go.

 

Sincerely,

 

Mike Scovel

SE Michigan

VariEze

 

Mbl     (313) 608-7202

Email   ezdriver@...

Email   info@...

             http://www.brighterstick.com

 

 

 

From: canard-aviators@canardzone.groups.io <canard-aviators@canardzone.groups.io> On Behalf Of Mike Tooze via groups.io
Sent: Sunday, May 3, 2020 3:35 PM
To: canard-aviators@canardzone.groups.io
Subject: Re: [c-a] Varieze Modification Questions

 

Hi Mike,

You are correct, the vortilon plans show three per wing.

Three per wing is fine as when I transitioned from cuffs to (3/w) vortilons I had to reevaluate the way I few both t/o and landing, mainly landings.  Difficult to describe but compared to cuffs she flies-in rather that bombs-in.

 

However such was the difference in takeoff that I decided to add a further v per wing.  This I scaled up from the plan's sequence of three and placed it with respect to the stagnation point/line.  I placed each extra midway between the innermost v and the wing root/ strake joint.

I used sealant as it was only an experiment - but they are still there!

 

The up side is that a friend says that in a formation t/o with two-up I get off the ground sooner than he with only one-up.  But it's not apples for apples as he has an O-200 powered VE. 

(There is also the possibility that the airflow from the new, innermost, vortilon may help aileron effectiveness - uncertain as my ailerons are slightly longer than standard.)

 

The down side is the 'switch-off' when, after a t/o you might lower the nose to gain speed more quickly, the AoA is inadvertently reduced leading to the vortilon affect reducing hence loss of some lift.  Not good if in a shorter field t/o.  

Caution - With four vortilons this is accentuated.

 

As this is against the standard I have never publicized this before now but I know of at least one other who has tried similar. (Not counting Gene who it seems to have acquired his V-E with four fitted.)

 

In summary:  Definitely do fit the vortilons, three per wing as plans, do not fly without them.(Or the cuffs which the vortilons superseded very effectively)

Only after fully evaluating the full flight envelope and becoming fully familiar with your particular Vari Eze should you consider changing anything at all.

 

Best regards,

 

Mike T O-235 Vari Eze

Trying not to confuse, (or write too often ;^)

 

 

 

 

 

 

On Sunday, 3 May 2020, 19:26:16 BST, nosedragger48154 <ezdriver@...> wrote:

 

 

Gentlemen, I am about to install my newly mad Vortilons on my VariEze wing.  However everything I saw when building my Vortilons, stated to use 3, never saw anything that said 4.  Am I missing something?

 

Sincerely,

 

Mike Scovel

SE Michigan

VariEze

 

Mbl     (313) 608-7202

Email   ezdriver@...

Email   info@...

             http://www.brighterstick.com

 

 

 

From: canard-aviators@canardzone.groups.io <canard-aviators@canardzone.groups.io> On Behalf Of Mike Tooze via groups.io
Sent: Saturday, May 2, 2020 7:37 AM
To: canard-aviators@canardzone.groups.io
Subject: Re: [c-a] Varieze Modification Questions

 

I would not normally think of backing up a point of Ken but this is such a safety issue.  Whatever you do,Gene, ensure this new Vari Eze has the plans design vortilons.

If removing what you call a 'vortilon' made a 3mph difference then it is not a vortilon. Not the vortilon that we are recommending

Please go back to the plans to re-check what you have against what you should have.  (I once saw a photo on [c-a] of a Rutan type with the vortilons mounted upside down, i.e. with the vorilons above the stagnation point. That would have a drag affect)

BTW Just for clarification.  My 720lb empty wt was the 1982 wt.  Much air has flown over the wings since then, example I'm minus the two Bendix mags (put those in your pocket to see the difference;-), the nav/com for a Terra760D then for a FUNKE 8.33.

Lastly check all the mails re wt&balance and trimming out, incl my contribution.

 

Above is not directed at Todd who welcome as doing a careful job in bringing his Vari Eze back into, I'm sure, good satisfying service.

 

Mike T

 

 

 

 

On Friday, 1 May 2020, 21:15:44 BST, KEN4ZZ via groupsio <ken4zz@...> wrote:

 

 

Do not, repeat, DO NOT remove your VariEze's vortilons unless you plan to retrofit wing cuffs, especially if you have a full electric O-235 = butt heavy. 

I flew my first several hundred hours slick winged, before Burt developed the cuffs - which I still have.  With a modestly aft, but within CG limits loading, the 'Saber Dance' divergent Dutch roll that was clearly spelled out in the original POH is indeed present.  I did a full exploration of the flight envelop - at altitude - during my phase one and at aft CG limit the aircraft would roll off after just a few cycles.  It almost certainly would not be survivable if it inadvertently happened in the pattern.  Cuffs or vortilons significantly reduce the Dutch roll to usually nothing but occasionally at most a mild, stable wing rock.

Ken

On 5/1/2020 1:05 PM, Gene via groups.io wrote:



 Plane came with vortilons, 4 per wing. I knocked one off (outboard starboard) flew it, picked up 3 MPH, re installed, lost the 3, knocked it back off and have flown 300 hours with the asymmetric 3 and 4 configuration. I'm considering removing all of them when I paint.