---------------------------------------------------------- Europa-List Digest Archive --- Total Messages Posted Fri 05/11/07: 16 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 12:43 AM - Re: Re: Votex Generators (Keith Hickling) 2. 01:39 AM - Re: paint shops (Alan) 3. 02:34 AM - Re: Votex Generators (flyingphil2) 4. 07:42 AM - paint shop (danny@mcwalterscafe.co.uk) 5. 08:12 AM - Re: Votex Generators (Fred Klein) 6. 08:21 AM - Re: Re: Votex Generators (D.Hetrick) 7. 08:34 AM - Re: Votex Generators (D.Hetrick) 8. 09:15 AM - Re: Votex Generators (flyingphil2) 9. 09:19 AM - Re: Re: Votex Generators () 10. 10:41 AM - Re: Votex Generators (rampil) 11. 10:57 AM - Re: Votex Generators (Graham Singleton) 12. 02:05 PM - Re: Re: Votex Generators (Graham Singleton) 13. 02:09 PM - Re: Votex Generators (karelvranken) 14. 03:05 PM - Re: Re: Votex Generators (Fred Klein) 15. 04:37 PM - Airbrake horn cover () 16. 04:52 PM - Re: Re: Votex Generators (Graham Singleton) ________________________________ Message 1 _____________________________________ Time: 12:43:45 AM PST US From: Keith Hickling Subject: Re: Europa-List: Re: Votex Generators Do they increase drag at higher speeds? Keith Hickling. ----- Original Message ----- From: "D.Hetrick" Sent: Friday, May 11, 2007 1:18 PM Subject: Re: Europa-List: Re: Votex Generators > > Fred, > I.m told that the VG's can ruduce the stall speeds by as much as 12 mph, > aircraft dependable of course. > I'm thinking seriously of giving it a try. > Dale > ----- Original Message ----- > From: "Fred Klein" > To: > Sent: Thursday, May 10, 2007 5:53 PM > Subject: Re: Europa-List: Re: Votex Generators > > >> >> >> On Thursday, May 10, 2007, at 02:41 PM, Graham Singleton wrote: >> >>> VGs were applied to the wing and canard of a Long EZ, which has laminar >>> sections on both, to reduce stall speed, the VGs re energise the laminar >>> boundary layer and help to prevent separation after the max thickness >>> point of the section. Stall was reduced by 7 kts. >>> Graham >> >> So here's a question... >> >> Is it conceivable that adding VGs to the Europa could reduce the stall >> speed sufficiently to meet the LSA requirements? >> >> >> >> >> >> > > > ________________________________ Message 2 _____________________________________ Time: 01:39:30 AM PST US From: "Alan" Subject: RE: Europa-List: paint shops Murray Flint in Norfolk did my tri gear early this year. He paints millions of Jabirus and has done a few Europas. When I shopped around his name was repeatedly recommended and I'm very pleased with the job he's done. murray@flint.flyer.co.uk 01945 780023 Alan -----Original Message----- From: owner-europa-list-server@matronics.com [mailto:owner-europa-list-server@matronics.com] On Behalf Of Richard Collings Sent: 10 May 2007 18:00 Subject: Re: Europa-List: paint shops It may seem a long way to go but you couldn't do much better than Mick Allen & Sons Ltd . Turweston Airfield, Brackley, Northants. They are in a purpose built building right next door to the PFA offices. ----- Original Message ----- From: Sent: Thursday, May 10, 2007 10:02 AM Subject: Europa-List: paint shops > > > Hi All, > My baby is getting very close to being ready to be painted. Can > anyone in the uk recommend a good paint shop. I reside in north wales, > but will be able to trail R.I. any where in the uk. > > Cheers Danny G-c.e.r.i. > > > -- > 269.6.6/795 - Release Date: 5/9/2007 15:07 > > ______________________________________________________________________ This email has been scanned by the MessageLabs Email Security System. For more information please visit http://www.messagelabs.com/email ______________________________________________________________________ ________________________________ Message 3 _____________________________________ Time: 02:34:43 AM PST US Subject: Re: Europa-List: Votex Generators From: "flyingphil2" This is developing into quite a discussion. I'm an aerodynamicist by trade and so here's my answers to the points above: 1. If someone wants to try VGs on a Europa then go ahead but I suspect they won't make any difference. The wing design is far more advanced than those seen on www.landshorter.com which tend to be things like the Kitfox etc. VGs may improve flow over the ailerons which will make the aircraft feel better at slow speeds and will improve controllability near the stall. With a poor wing design they may reduce the stall speed. Don Dykins used a lot of his (and his department's) experience in the Europa wing and that was previously used on aircraft like the BAe 146 and early Airbus. 2. Graham is right about the Long Eze and the way in which the VGs helped. I guess the laminar region on the canards was probably the first 25% of the chord and there was a trailing edge separation. The Europa is designed to have a larger laminar region with no separation and so the VGs will not help in this case. 3. To reduce the stall speed on the Europa you would need to have a more powerful flap with maybe an additional 'flap vane' ahead of the main flap or something like leading edge slats. You could try a 'blown' wing as well if you were keen. On another point: NACA intakes are designed to be an efficient and low drag intake method. The edges of the intake generate small vortices which the flow down the intake and they work very well indeed if positioned in the right place. I think Duncan's issue may be down to a positioning problem and you won't improve the flow down that duct with a VG at high aoa if the flow isn't going that way in the first place. That brings me on to another point. I routinely run large computer simulations of external aerodynamic cases in my job. I'm quite keen to look at a Europa but need some CAD geometry. The factory doesn't have any as the moulds were hand made so my question is has anyone, who has too much spare time on their hands, made a good quality CAD representation of a Europa? I know there are some models floating round for flight simulators but they are far too basic for what I would need. Regards, Phil Visit - www.EuropaOwners.org ________________________________ Message 4 _____________________________________ Time: 07:42:51 AM PST US From: "danny@mcwalterscafe.co.uk" Subject: Europa-List: paint shop Thanks for all the recommendations. Time to start making a few phone call. Cheers Danny ________________________________ Message 5 _____________________________________ Time: 08:12:08 AM PST US Subject: Re: Europa-List: Votex Generators From: Fred Klein Phil, The resourceful minds plugged into this forum never cease to amaze me...thanks for sharing your knowledge of VGs. Would you care to opine as to the aerodynamics of the wingroot/flap/fuselage intersection and what might be done to reduce drag in this area? Fred A194 On Friday, May 11, 2007, at 02:33 AM, flyingphil2 wrote: > > I'm an aerodynamicist by trade and so here's my answers to the points > above: ________________________________ Message 6 _____________________________________ Time: 08:21:33 AM PST US From: "D.Hetrick" Subject: Re: Europa-List: Re: Votex Generators Keith, Not according to their information. Dale ----- Original Message ----- From: "Keith Hickling" Sent: Thursday, May 10, 2007 7:41 PM Subject: Re: Europa-List: Re: Votex Generators > > > Do they increase drag at higher speeds? > > Keith Hickling. > > ----- Original Message ----- > From: "D.Hetrick" > To: > Sent: Friday, May 11, 2007 1:18 PM > Subject: Re: Europa-List: Re: Votex Generators > > >> >> Fred, >> I.m told that the VG's can ruduce the stall speeds by as much as 12 mph, >> aircraft dependable of course. >> I'm thinking seriously of giving it a try. >> Dale >> ----- Original Message ----- >> From: "Fred Klein" >> To: >> Sent: Thursday, May 10, 2007 5:53 PM >> Subject: Re: Europa-List: Re: Votex Generators >> >> >>> >>> >>> On Thursday, May 10, 2007, at 02:41 PM, Graham Singleton wrote: >>> >>>> VGs were applied to the wing and canard of a Long EZ, which has laminar >>>> sections on both, to reduce stall speed, the VGs re energise the >>>> laminar boundary layer and help to prevent separation after the max >>>> thickness point of the section. Stall was reduced by 7 kts. >>>> Graham >>> >>> So here's a question... >>> >>> Is it conceivable that adding VGs to the Europa could reduce the stall >>> speed sufficiently to meet the LSA requirements? >>> >>> >>> >>> >>> >>> >> >> >> >> >> > > > ________________________________ Message 7 _____________________________________ Time: 08:34:34 AM PST US From: "D.Hetrick" Subject: Re: Europa-List: Votex Generators Phil, Thank you very much for your insight on VG's. Guess I had better wait until after you run your simulations before adding them. Thanks again, Dale ----- Original Message ----- From: "flyingphil2" Sent: Friday, May 11, 2007 2:33 AM Subject: Re: Europa-List: Votex Generators > > This is developing into quite a discussion. I'm an aerodynamicist by > trade and so here's my answers to the points above: > > 1. If someone wants to try VGs on a Europa then go ahead but I suspect > they won't make any difference. The wing design is far more advanced than > those seen on www.landshorter.com which tend to be things like the Kitfox > etc. VGs may improve flow over the ailerons which will make the aircraft > feel better at slow speeds and will improve controllability near the > stall. With a poor wing design they may reduce the stall speed. Don > Dykins used a lot of his (and his department's) experience in the Europa > wing and that was previously used on aircraft like the BAe 146 and early > Airbus. > > 2. Graham is right about the Long Eze and the way in which the VGs > helped. I guess the laminar region on the canards was probably the first > 25% of the chord and there was a trailing edge separation. The Europa is > designed to have a larger laminar region with no separation and so the VGs > will not help in this case. > > 3. To reduce the stall speed on the Europa you would need to have a more > powerful flap with maybe an additional 'flap vane' ahead of the main flap > or something like leading edge slats. You could try a 'blown' wing as > well if you were keen. > > On another point: > > NACA intakes are designed to be an efficient and low drag intake method. > The edges of the intake generate small vortices which the flow down the > intake and they work very well indeed if positioned in the right place. I > think Duncan's issue may be down to a positioning problem and you won't > improve the flow down that duct with a VG at high aoa if the flow isn't > going that way in the first place. That brings me on to another point. I > routinely run large computer simulations of external aerodynamic cases in > my job. I'm quite keen to look at a Europa but need some CAD geometry. > The factory doesn't have any as the moulds were hand made so my question > is has anyone, who has too much spare time on their hands, made a good > quality CAD representation of a Europa? I know there are some models > floating round for flight simulators but they are far too basic for what I > would need. > > Regards, > > Phil > > > Visit - www.EuropaOwners.org > > > ________________________________ Message 8 _____________________________________ Time: 09:15:21 AM PST US Subject: Re: Europa-List: Votex Generators From: "flyingphil2" Hi Fred, Well my thoughts on this would be as follows: 1. Is there a problem in that area? Oil flow tests would show up any separations in that area or maybe someone with a dirty aircraft has flown through rain and has some pictures of the surface flow patterns that were left. If there is no obvious problem then I'd leave it alone. 2. If there is a problem then making a really good job of the wing fillets would be the best approach and maybe trying to maximise the radius of that fillet (larger radius = better). The problem with a large radius is what happens when you come to the trailing edge of the wing (or in the Europa's case, where the wing ends and the flap starts). You need to lose that large radius and run it out to nothing smoothly. 3. Sealing the wing against the fuselage would definitely be good. On gliders, we use PVC tape but that only works if you have a small 'wing stub' moulded into the fuselage that the wing butts up to. On a Europa I would say that some high density foam on the inside of the wing root fillet would do the trick and when the wings are fitted, the foam is compressed and thus forms a nice seal. I.m not sure what gaps people have between the fuselage and the wing fillets but try and keep them as small as possible. In terms of drag reduction I would have thought that there is little to do on the Europa. It's already an excellent design and the use of composite materials (and ability to build almost any shape) helps this. Compared to some homebuilts on the market using the same engine, it has to be a very efficient machine. Having said that, you notice the difference on a glider if the wing roots are not taped and the controls are not sealed and so all these little bits of attention to detail would add up and help reduce the drag that little bit further. Actually, that's an interesting point above. Out of all the homebuilts powered with a 912S, there can't be many aircraft that are faster than a Europa. There is the DynAero MCR1 (which I had an amazing flight in once) and that is very fast but look at the size of it - it's tiny. Anyone have any other comparisons? Phil Visit - www.EuropaOwners.org ________________________________ Message 9 _____________________________________ Time: 09:19:52 AM PST US Subject: Re: Europa-List: Re: Votex Generators From: A few negatives to keep in mind with Vortex generators: Cleaning = PIA Waxing = PIA Painting = PIA Another thing to break Ron Parigoris ________________________________ Message 10 ____________________________________ Time: 10:41:27 AM PST US Subject: Europa-List: Re: Votex Generators From: "rampil" Re Conversion to LSA specs Europa04 and Custom Flight Creations (AKA Europa USA) currently has Bud Yerly working on a new wing design to meet the LSA spec and be easier and less expensive. As I noted previously in the forum, Bud is the only guy I who has a degree in ->Low Speed -------- Ira N224XS Read this topic online here: http://forums.matronics.com/viewtopic.php?p=112268#112268 ________________________________ Message 11 ____________________________________ Time: 10:57:45 AM PST US From: Graham Singleton Subject: Re: Europa-List: Votex Generators Phil the nioest wing root I've seen is Ted and Justin's, small radius at the LE, large at the TE. picture attached. imho this is the way to do it, the fillet needs to be flexible to allow wing bending without crushing the fuselage side, so no more than 3 plies of BID at the edge. There are several Europas with this style but only Ted's has the elegant change of radius moving aft. Easier to rig a wing done like this too, something to line up with as it goes in. Graham flyingphil2 wrote: > > Hi Fred, > > Well my thoughts on this would be as follows: > > 1. Is there a problem in that area? Oil flow tests would show up any separations in that area or maybe someone with a dirty aircraft has flown through rain and has some pictures of the surface flow patterns that were left. If there is no obvious problem then I'd leave it alone. > > 2. If there is a problem then making a really good job of the wing fillets would be the best approach and maybe trying to maximise the radius of that fillet (larger radius = better). The problem with a large radius is what happens when you come to the trailing edge of the wing (or in the Europa's case, where the wing ends and the flap starts). You need to lose that large radius and run it out to nothing smoothly. > > 3. Sealing the wing against the fuselage would definitely be good. On gliders, we use PVC tape but that only works if you have a small 'wing stub' moulded into the fuselage that the wing butts up to. On a Europa I would say that some high density foam on the inside of the wing root fillet would do the trick and when the wings are fitted, the foam is compressed and thus forms a nice seal. I.m not sure what gaps people have between the fuselage and the wing fillets but try and keep them as small as possible. > > In terms of drag reduction I would have thought that there is little to do on the Europa. It's already an excellent design and the use of composite materials (and ability to build almost any shape) helps this. Compared to some homebuilts on the market using the same engine, it has to be a very efficient machine. Having said that, you notice the difference on a glider if the wing roots are not taped and the controls are not sealed and so all these little bits of attention to detail would add up and help reduce the drag that little bit further. > > Actually, that's an interesting point above. Out of all the homebuilts powered with a 912S, there can't be many aircraft that are faster than a Europa. There is the DynAero MCR1 (which I had an amazing flight in once) and that is very fast but look at the size of it - it's tiny. Anyone have any other comparisons? > > Phil > > > > > > > Visit - www.EuropaOwners.org > > > > > > > > > -- Graham Singleton Tel: +441629820187 Mob: +447739582005 ________________________________ Message 12 ____________________________________ Time: 02:05:22 PM PST US From: Graham Singleton Subject: Re: Europa-List: Re: Votex Generators Fred The stall on the Europa is critically affected by the position and size of the LE radius, Don and his aerodynamicist friend David tweaked the leading edge, it's quite a sharp radius and there is a minute bulge underneath. Hard to spot it but it does have a marked effect if it isn't accurate. On a couple of Europas I was involved with (both Classics) I made templates of the first 10 inches of section at about 8 stations and the builders spent many hours sanding to these templates. The stalls on both these aircraft are relatively benign, unlike that of G-KWIP. Both are fast too. It is all too easy to sand off the bumps in the section which are meant to be there. I have tried to attach a dwg file of the section coordinates/ Graham Fred Klein wrote: > > > On Thursday, May 10, 2007, at 02:41 PM, Graham Singleton wrote: > >> VGs were applied to the wing and canard of a Long EZ, which has >> laminar sections on both, to reduce stall speed, the VGs re energise >> the laminar boundary layer and help to prevent separation after the >> max thickness point of the section. Stall was reduced by 7 kts. >> Graham > > > So here's a question... > > Is it conceivable that adding VGs to the Europa could reduce the stall > speed sufficiently to meet the LSA requirements? > ________________________________ Message 13 ____________________________________ Time: 02:09:54 PM PST US From: "karelvranken" Subject: Re: Europa-List: Votex Generators Phil, Graham and all, In attachment my solution for the wing root drag problem. While building I fixed the fairing as well to the wing as to the fuselage and cut it vertical with the wing root. Then I reinforced both to become entire part and sufficient solid. I also prolonged the upper side at the fuselage to cover the gap for the flap torque tube so that no spoiled fuel or water could penetrate the fuselage. This solution gave me some advantages: - the fuselage is certainly reinforced - the rigging of the wing is easier because you see exactly were the root has to meet - sealing with tape is easy as I did before with my gliders. Thank you Phil for your much apreciated intervention. Karel Vranken. ----- Original Message ----- From: "Graham Singleton" Sent: Friday, May 11, 2007 7:58 PM Subject: Re: Europa-List: Votex Generators > Phil > the nioest wing root I've seen is Ted and Justin's, small radius at the > LE, large at the TE. picture attached. imho this is the way to do it, > the fillet needs to be flexible to allow wing bending without crushing > the fuselage side, so no more than 3 plies of BID at the edge. There are > several Europas with this style but only Ted's has the elegant change of > radius moving aft. > Easier to rig a wing done like this too, something to line up with as it > goes in. > Graham ________________________________ Message 14 ____________________________________ Time: 03:05:46 PM PST US Subject: Re: Europa-List: Re: Votex Generators From: Fred Klein Graham, Sorry I was not clear in my email to you. My references to Ted's radii were to his trailing edge fillet were to the fillet at the rear of the flap as viewed in plan form, not in cross section...I would not be one to mess with Don and David's leading edge! Fred On Friday, May 11, 2007, at 02:05 PM, Graham Singleton wrote: > Fred > The stall on the Europa is critically affected by the position and > size of the LE radius, Don and his aerodynamicist friend David tweaked > the leading edge, it's quite a sharp radius and there is a minute > bulge underneath. Hard to spot it but it does have a marked effect if > it isn't accurate. > On a couple of Europas I was involved with (both Classics) I made > templates of the first 10 inches of section at about 8 stations and > the builders spent many hours sanding to these templates. The stalls > on both these aircraft are relatively benign, unlike that of G-KWIP. > Both are fast too. It is all too easy to sand off the bumps in the > section which are meant to be there. > I have tried to attach a dwg file of the section coordinates/ > Graham > Fred Klein wrote: >> On Thursday, May 10, 2007, at 02:41 PM, Graham Singleton wrote: >>> VGs were applied to the wing and canard of a Long EZ, which has >>> laminar sections on both, to reduce stall speed, the VGs re energise >>> the laminar boundary layer and help to prevent separation after the >>> max thickness point of the section. Stall was reduced by 7 kts. >>> Graham >> So here's a question... >> Is it conceivable that adding VGs to the Europa could reduce the >> stall speed sufficiently to meet the LSA requirements? > > -- > This message has been scanned for viruses and > dangerous content by MailScanner, and is > believed to be clean. > > ________________________________ Message 15 ____________________________________ Time: 04:37:05 PM PST US Subject: Europa-List: Airbrake horn cover From: Would appreciate input how to cover airbrake control horn under pilot right thigh. Picture? Thx. Ron Parigoris ________________________________ Message 16 ____________________________________ Time: 04:52:15 PM PST US From: Graham Singleton Subject: Re: Europa-List: Re: Votex Generators Neither would I! I was replying to your earlier email Fred, asking about stall speeds & VGs Graham Fred Klein wrote: > > Graham, > > Sorry I was not clear in my email to you. My references to Ted's radii > were to his trailing edge fillet were to the fillet at the rear of the > flap as viewed in plan form, not in cross section...I would not be one > to mess with Don and David's leading edge! > > Fred > ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message europa-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/Europa-List.htm Web Forum Interface To Lists http://forums.matronics.com Matronics List Wiki http://wiki.matronics.com Full Archive Search Engine http://www.matronics.com/search 7-Day List Browse http://www.matronics.com/browse/europa-list Browse Digests http://www.matronics.com/digest/europa-list Browse Other Lists http://www.matronics.com/browse Live Online Chat! http://www.matronics.com/chat Archive Downloading http://www.matronics.com/archives Photo Share http://www.matronics.com/photoshare Other Email Lists http://www.matronics.com/emaillists Contributions http://www.matronics.com/contribution ------------------------------------------------------------------------------------- These Email List Services are sponsored solely by Matronics and through the generous Contributions of its members.