Stearman65 Posted December 17, 2018 Share Posted December 17, 2018 I've just ordered this kit & plan to up rate it to as near as possible to scale. I have been looking for 3 view drawings to determine the type of air brake or spoiler was original. I've found lots of general pictures, but the only one showing air brakes had the knife type, but these could have been retro fitted as I believe the original had barn door type spoilers. Help please. The picture shows an earlier version, maybe a 6. Edited By Stearman65 on 17/12/2018 15:28:05 Quote Link to comment Share on other sites More sharing options...
simon barr Posted December 17, 2018 Share Posted December 17, 2018 That I believe is a Ka4... It has spoilers on the top of the wings only. The Ka8 is a single seater and has brakes top and bottom of the wing. Quote Link to comment Share on other sites More sharing options...
Frank Skilbeck Posted December 17, 2018 Share Posted December 17, 2018 Wikipedia is your friend, https://en.wikipedia.org/wiki/Schleicher_K_8 full size fitted with Schempp-Hirth air brakes in the upper and lower surfaces. All the scratch built models I've seen of the K8 are built this way as was the long lamented Flair kit http://www.flairmodels.co.uk/Aircraft/Classic_scale/ASK8_review.htm Quote Link to comment Share on other sites More sharing options...
Stearman65 Posted December 17, 2018 Author Share Posted December 17, 2018 Posted by Frank Skilbeck on 17/12/2018 16:24:46: Wikipedia is your friend, https://en.wikipedia.org/wiki/Schleicher_K_8 full size fitted with Schempp-Hirth air brakes in the upper and lower surfaces. All the scratch built models I've seen of the K8 are built this way as was the long lamented Flair kit http://www.flairmodels.co.uk/Aircraft/Classic_scale/ASK8_review.htm I had checked Wikipedia but it doesn't lead to any drawings showing the position of the brakes. I've even got the BGA spec page, that goes as far as giving the tyre pressure, but no drawings. **LINK** Quote Link to comment Share on other sites More sharing options...
Ron Gray Posted December 17, 2018 Share Posted December 17, 2018 Have you tried Pinterest? A quick search yields this https://goo.gl/images/4L79Gg Edited By Ron Gray on 17/12/2018 22:45:50 Quote Link to comment Share on other sites More sharing options...
Stearman65 Posted December 17, 2018 Author Share Posted December 17, 2018 Just done some more ferreting around & I'm sure the Ka8B was fitted with knife / scissor type air brakes which the mechanical versions have gone off the market, although there is a guy on Ebay trying to off load multiple used sets for £45, which might be a decent buy looking at those with built in electronics? Edited By Stearman65 on 17/12/2018 23:17:43 Quote Link to comment Share on other sites More sharing options...
Stearman65 Posted December 18, 2018 Author Share Posted December 18, 2018 Got an email from Fed Ex this morning. my kit has left Champagne Illinois & has arrived in Memphis Tennessee. Supposed to be with me in Southport by 12 noon, Wednesday 19th Dec'. Quote Link to comment Share on other sites More sharing options...
Robin Colbourne Posted December 18, 2018 Share Posted December 18, 2018 This page clearly shows the scissor brake coming out of the underside of the wing. The airbrakes are just behind the spar, which for, maximum depth and therefore strength, as that the thickest part of the wing chord. You may want to omit the lower airbrakes as they are very vulnerable if landing in long grass. This, and their effect of reducing efficiency of the wing by allowing air to leak through from bottom to top, are why they have gone out of fashion on full size gliders. **LINK** The full-size K8 is a lovely glider to fly, being extremely light on the controls. Unfortunately the seat gets very uncomfortable (numb bum) at about the one hour point. The K18 is equally light on the controls but has a more spacious cockpit and is much more pleasant on a long flight. If you contact your local gliding club, they can probably tell you where there is a K8 that you could have a look around. Otherwise tell us where you are and someone can point you to a K8 nearby. Edited By Robin Colbourne on 18/12/2018 11:22:58 Quote Link to comment Share on other sites More sharing options...
Stearman65 Posted December 18, 2018 Author Share Posted December 18, 2018 Posted by Robin Colbourne on 18/12/2018 11:22:14: If you contact your local gliding club, they can probably tell you where there is a K8 that you could have a look around. Otherwise tell us where you are and someone can point you to a K8 nearby. Edited By Robin Colbourne on 18/12/2018 11:22:58 Thanks Robin I have a copy of the BGA directory showing all the K8B's registered in the UK. Not had time to sort one out yet but it's on my list of things to do. I may strip off the Orafilm covering as it isn't scale like & I intend to fit spoilers in the wings, not sure about fitting them in only the top, it's not scale & could have adverse effects when deploying?. Looking at the 250mm electro units at £59 per pair, which don't need servos. I've got some samples of Oratex gloss coming after Christmas which looks as near as dammit to the Orafilm on the kit. Regards Eric Quote Link to comment Share on other sites More sharing options...
Martin Harris - Moderator Posted December 18, 2018 Share Posted December 18, 2018 The effect of top and bottom surface airbrake leakage rather depends on whether you subscribe to the modern "Newtonian" theory of lift or hang on to the "Bernoulli" explanation! In my very inexpert opinion, I favour a combination of the two...especially having experienced some of the brake performance of earlier top surface sealed brakes (the SHK and Standard Libelle come to mind). I built a model of the Rhonbussard (a much earlier Schleicher product) that I used to have a share in, which had been heavily modified by a German university group back in the mists of time including the very small top and bottom surface airbrakes that had replaced the original rather ineffective top surface spoilers (I doubt the new paddles were longer than 3 feet). These were extremely effective in both the full size and model versions. This picture shows the small dimensions of the brake paddles. It wasn't taken after a very heavy landing - I needed the wheels and a tow rope where I was going! As long as there aren't massive gaps when they're closed, duplicating full size will be scale and you shouldn't suffer significant performance degradation. They provide far better effectiveness than using top surface only brakes but I can see no reason why there would be any problem should you prefer to go that way. Edited By Martin Harris on 18/12/2018 13:51:40 Quote Link to comment Share on other sites More sharing options...
Frank Skilbeck Posted December 18, 2018 Share Posted December 18, 2018 If you are stripping the covering off the wings then it would be worthwhile checking the glue joints and spars, the 6m version had a tendency to lose a wing in flight (they were all sold off cheap by the then UK importer with the caveat that the the owner fixed this, if you search on line this was well documented on some gliding forums), I did see one 3.5m version at an aerotow suffer a wing failure too. But the 6m and 3.5m versions are both very good fliers (having said that I haven't seen a Ka8 that isn't a good flier!) Also on my CW Slingsby Eagle has top and bottom scissor brakes, these are built up as shown at around 1.43 in this video https://www.youtube.com/watch?v=AzCaJaF7dvM Quote Link to comment Share on other sites More sharing options...
Stearman65 Posted December 18, 2018 Author Share Posted December 18, 2018 Hi Frank I've read most of the comments on Youtube & the forums. It's the incidence on the tailplane & the CG that caused most comments. The original comic said 100 mm from L/e, this was later corrected to 80mm, cost Tower & Great Planes a lot of money. But I will check the glue joints & maybe add an extra tube if I do strip it. The kit's over the Atlantic at present. I'll check your YT link, but I may have seen that also? Regards Eric Quote Link to comment Share on other sites More sharing options...
Stearman65 Posted December 18, 2018 Author Share Posted December 18, 2018 Hi again Frank. Checked the YT link, not sure if it's one I've seen but there was a quick flash of the internals of the air brake, looks a lot cheaper than the £100 pair of electric jobbies. Scree shot picture attached. Quote Link to comment Share on other sites More sharing options...
Stearman65 Posted December 20, 2018 Author Share Posted December 20, 2018 Update on delivery. FEDUP WITH FEDEX Should have been delivered before noon yesterday, it wasn't. Since then, 10 emails & 12 phone calls, they have this morning confirmed it will be with me before 12 noon today. Paid a customs bill of £55, never buying outside the EU again, not worth the hassle. While doing all the above I went back onto Pheonix models site in Viet Namm & saw they do a Bergfalke at just over 3m. **LINK** Quote Link to comment Share on other sites More sharing options...
Ron Gray Posted December 20, 2018 Share Posted December 20, 2018 Patience is a virtue, Victor. Edited By Ron Gray on 20/12/2018 10:15:33 Quote Link to comment Share on other sites More sharing options...
Stearman65 Posted December 20, 2018 Author Share Posted December 20, 2018 The Eagle (Ka8B) has landed. Arrived around 11am, box relatively un-marked apart from a distinct rattle. Un-packed it in the bedroom & apart from a few items floating around unfettered, & some loose patches of film. It looks OK. Pleased they've replaced the pilot with something more akin to reality. As I was unpacking on the bed, my mind went 50 years to my time in the local club, where one the members had woken up one morning & found his latest model where his wife should have been!!! Quote Link to comment Share on other sites More sharing options...
Martin Harris - Moderator Posted December 20, 2018 Share Posted December 20, 2018 Why can't ARTF suppliers ever get pilot sizes right? That pilot should more or less fill the cockpit widthwise and his feet should be less than a couple of inches from the front of the nose... Edited By Martin Harris on 20/12/2018 13:46:19 Quote Link to comment Share on other sites More sharing options...
Stearman65 Posted December 20, 2018 Author Share Posted December 20, 2018 Posted by Martin Harris on 20/12/2018 13:44:44: Why can't ARTF suppliers ever get pilot sizes right? That pilot should more or less fill the cockpit widthwise and his feet should be less than a couple of inches from the front of the nose... Edited By Martin Harris on 20/12/2018 13:46:19 Maybe mine's starting young? Quote Link to comment Share on other sites More sharing options...
Stearman65 Posted January 2, 2019 Author Share Posted January 2, 2019 Had a change of plans over Christmas, this untouched kit is for sale. Not available in the UK, see classifieds on here. Quote Link to comment Share on other sites More sharing options...
simon barr Posted January 2, 2019 Share Posted January 2, 2019 Why the change of heart, Stearman? Should go together pretty quickly and they fly well. If you wanted to "scale" it up a bit, just change the pilot as he is far too small (as mentioned before), and fit the top surface brakes.... No-one will know that they are not true scale. I have the Seagull version, and having done as I suggest, I am very pleased with it... I fly it off the slope and aerotow. At least give it a go, you seemed so keen at the beginning. Quote Link to comment Share on other sites More sharing options...
Stearman65 Posted January 2, 2019 Author Share Posted January 2, 2019 It's the same situation as I had with the Stearman, it's just too big. A case of my eyes being bigger than my belly, as my Mum used to say. I've got my eyes set on the World Models Pilatus Porter, which at 64inch with a 2 piece wing will fit my facilities. I still have the TM Challenger which I will start after 12th night & the decorations have gone. Quote Link to comment Share on other sites More sharing options...
simon barr Posted January 2, 2019 Share Posted January 2, 2019 When you say it's too big, do you mean flying wise or transport wise or storage? If it's flying wise, don't let the size put you off.... This sort of glider just floats around and will not catch you out. As for storage and transport... well that's a matter for you to decide, but with it breaking down, it won't take up as much room as you would think. I just think it's a shame that you were so keen and are now giving up on the model before you've started, but of course that's your choice. Quote Link to comment Share on other sites More sharing options...
Stearman65 Posted January 2, 2019 Author Share Posted January 2, 2019 It would have been a project that could have cost quite a bit if I had done what I intended. Once finished the chances of flying it would be few & far between. So I took the decision to get something more practical that would still be a project but less costly & more usable when complete. The WM Pilatus is available as a laser cut kit, so I can pick my own colour scheme, not have the one on the ARTF version. Edited By Stearman65 on 02/01/2019 17:18:06 Quote Link to comment Share on other sites More sharing options...
Stearman65 Posted January 13, 2019 Author Share Posted January 13, 2019 The Pheonix Ka8B 3.5m 1/4 scale artf glider / motor glider kit is now for sale on Ebay as well as the classifieds here. Edited By Pete B - Moderator on 13/01/2019 14:58:55 Quote Link to comment Share on other sites More sharing options...
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