Biggles' Elder Brother - Moderator Posted March 22, 2016 Author Share Posted March 22, 2016 Not a huge amount of progress at the moment, I have been busy with other stuff yesterday and today. But I have fed the elevator and rudder servo leads down through the tail boom and out into the upper pod - wasn't that a fun experience! I've also fitted the motor at the business end. I had to make-up a ply mounting plate as the spacing of the mounting holes provided do not fit a standard spider mount - what are they thinking of? Anyway, job done. To be honest I am not 100% satisfied with the solidity of the motor mount. My bit's OK - it's their base plate that concerns me, I've see stiffer mountings! BEB Quote Link to comment Share on other sites More sharing options...
Ryan Doig Posted March 26, 2016 Share Posted March 26, 2016 Subd and following with interest. While it might not be the best looking model it sounds like it will fit your purpose for it so the look doesn't matter. While surveying you won't be looking at the model lol smooth flight, view and realiabilty is what you need 👍🏻 will check in when I can. Ryan Quote Link to comment Share on other sites More sharing options...
Wingman Posted March 26, 2016 Share Posted March 26, 2016 Isn't there some theory that models end up looking like their owners? Quote Link to comment Share on other sites More sharing options...
cymaz Posted March 26, 2016 Share Posted March 26, 2016 It's dogs mate ? I don't think BEB is a cyclops.... Edited By cymaz on 26/03/2016 23:15:51 Edited By cymaz on 26/03/2016 23:16:15 Edited By cymaz on 26/03/2016 23:17:12 Quote Link to comment Share on other sites More sharing options...
Biggles' Elder Brother - Moderator Posted March 27, 2016 Author Share Posted March 27, 2016 It seems to be destined that the only days I can get to work on this are Sundays! Anyway a bit more done today - it was time to tackle fixing the fin/tailplane in place. As I said above this was always going to be a tricky operation.The rudder has a tube along its base; a second tube, fixed to the tailplane, slides into this first tube. Then all this slides onto the fuselage tail boom tube. So, three concentric tubes. Each tube has a 3mm transverse hole, the idea is to line all three tubes up so you can pass an M3 bolt through the lot, fasten it up and hey presto - attached tail assembly. If I ever meet whoever came up with this idea I'll will cheerfully straggle them! This collction of holes is of course inside the whole assembly - you can't see it! The task is almost impossible - almost, but not quite! It took me two hours and countless abortive attempts, but I did manage it using a small cross-head screwdriver with a shaft of exactly 3mm as a mandrel and with a little help from some Vaseline to smooth the adjustment! Here's the dreaded external hole after assembly... Here is an overview of the tail which shows just how small the rudder is..... Here is a view from underneath the tail assembly showing the elevator control horn and the run to the elevator servo located in the servo tray on the tail boom... Next up we can start installing the radio gear. This will be mounted in the upper pod. It is important to try to separate the control radio gear from the FPV equipment as far as possible - so as to avoid possible interference. So, control gear in the upper pod and FPV gear in the lower pod. Even with this separation its still a good idea to get the Rx "out of the way" - so I've elected to mount it towards the rear of the pod... Finally today - the lower pod seams have to be glued up.... And a view from the back with the aircraft inverted... So, ESC to be installed next and then we can apply power to everything, centralise the servos and finalise the control push rods etc. BEB Quote Link to comment Share on other sites More sharing options...
Peter Miller Posted March 27, 2016 Share Posted March 27, 2016 Don't yopu wish that you were wprking with balsa and ply? Quote Link to comment Share on other sites More sharing options...
Biggles' Elder Brother - Moderator Posted March 27, 2016 Author Share Posted March 27, 2016 Yeap! But working practices dictate otherwise. When its operational foam construction will be more pratical and it reduces cost and repair times. BEB Quote Link to comment Share on other sites More sharing options...
Nigel Grant 1 Posted March 28, 2016 Share Posted March 28, 2016 An air museum 80k's to the South of us in Ashburton NZ has a picture on their web page of a Transavia PL-2 Airtruk which they have on display. The address of the page is **LINK** . Hope this works as I haven't yet learnt to paste links or pictures sorry. I'm not sure if it is the colouring or the shape that bears some resemblance to BEB's acquisition. I cant really make light of the planes appearance as whilst I was initially amused at the vision, the accompanying article from the page, and also on Wikipedia, points out that the design was based on a New Zealand designed "air"craft called a Bennets airtruck, which is also described and pictured in Wiki. Quote Link to comment Share on other sites More sharing options...
Peter Miller Posted March 28, 2016 Share Posted March 28, 2016 About 35 years ago I did a very nice control line model of the Airtruk. It flew but not very well. It did cause a lot of interest at Old Warden Scale day though. Quote Link to comment Share on other sites More sharing options...
Biggles' Elder Brother - Moderator Posted March 28, 2016 Author Share Posted March 28, 2016 Nigel, I am forever in your debt! You have saved my self-esteem! Here is a picture of the aircraft Neil is referring to: And there's me thinking I had the world's ugliest aeroplane! BEB Edited By Biggles' Elder Brother - Moderator on 28/03/2016 09:16:26 Quote Link to comment Share on other sites More sharing options...
Peter Miller Posted March 28, 2016 Share Posted March 28, 2016 There is film of it flying towards the end of Mad Max Beyond the Thunderdome. Quote Link to comment Share on other sites More sharing options...
iqon Posted March 28, 2016 Share Posted March 28, 2016 I hope hobbyking dont see that picture. Quote Link to comment Share on other sites More sharing options...
Josip Vrandecic -Mes Posted March 28, 2016 Share Posted March 28, 2016 Beauty is in the eye of the beholder.... who has just died after he saw the above mentioned '' beautiful '' flying machine Quote Link to comment Share on other sites More sharing options...
john stones 1 - Moderator Posted March 28, 2016 Share Posted March 28, 2016 Oh dear I quite like it John Quote Link to comment Share on other sites More sharing options...
Martin McIntosh Posted March 28, 2016 Share Posted March 28, 2016 Well, I am glad that at least one person discarded those hideous screw on connectors BEB. Makes the brickbats worthwhile although I am surprised that you did not delete a couple of particularly vitriolic posts from a member who thinks that banning them in a club is a holier than thou act by the safety officer. The model actually looks OK and practical to me but then I like wierdo ones. Would be interested but the stick in the muds at my club want to ban FPV in general/quads with FPV or not, without even seeing one in action. Anyone wanna buy some quads/goggles/ video Tx`s/5.8Rx`s etc? Quote Link to comment Share on other sites More sharing options...
Biggles' Elder Brother - Moderator Posted March 28, 2016 Author Share Posted March 28, 2016 More potering about today,....time to get some power on this thing. The main battery will be a 4s, 10,000mAh.... A big beastie! The question is "where to put it?". Answers on a postcard please to,....stop making up you rown jokes at the back! Seriously, it can't go in the upper pod - it's just too big. So it will have to be the bottom pod, plenty of room in there as you can see below,... But with the battery in the bottom pod and the motor in the top pod - not to mention that the Rx is in the top pod as well - where should we put the ESC so that everything can be reached? I have decided that the solution is to fix the ESC to the roof of the bottom pod. That way the power leads will reach to the battery below it, the motor leads can pass out through a hole in the front (which will also offer some cooling) to the motor itself just above it. And the throttle servo lead can pass from the bottom pod, through a sort of "service duct" into the top pod and to the Rx. To do this we will need a self and back stop plate for the ESC to fix it to the roof of the top pod - enter the ply and balsa!!!... So with that in place, and the ESC inserted, it looks like below (note: this is the lower pod inverted. So the ESC appears at the bottom of the lower pod, but in reality is at the top of the lower pod - on the ceiling!)... So now the servo lead can run up (down in the picture above!) through the service duct that lies bewteen those ply side plates you can see, and it emerges on the top pod surface just by the Rx as shown,... The ESC's motor wires can be taken out the hole and connected as shown below... We can tidy those up a bit once we have established which way the motor is rotating! So here's an overall shot, showing the battery in approximate position, the connection to the ESC, the motor connections and the throttle servo lead up on the top pod rady to be plugged into the Rx... OK that's the power system all done. Time this aeroplane had some wheels I think. As I said above the main wheels supplied are far, far too small for use on anything other than perfect tramac. They would also give the Skua a very strong "nose-up" ground posture that could present problems with premature take offs etc in windy conditions (despite its relatively high weight for an FPV aircraft the Skua's wing loading is very low). Anyway I've fitted much larger wheels and I think they look better too - here's a shot of the fuselage (fuslages?) with the wheels in place and all more or less complete now... So, what remains to be done to have a functional airframe? 1. Control linkages for the elevator and rudder need to be fabricated and installed. 2. The wing fixings need to be sorted and the wings trial mounted. 3. Servos connected, centred and all the throws need to be set - no indications what they should be! 4. We need to find some way of fastening the battery down! Once that is done I will maiden it with a VLOS flight to just "shake-down" all the flight systems prior to starting to fit the FPV gear. BEB Quote Link to comment Share on other sites More sharing options...
Biggles' Elder Brother - Moderator Posted March 28, 2016 Author Share Posted March 28, 2016 Posted by Martin McIntosh on 28/03/2016 18:45:58: Well, I am glad that at least one person discarded those hideous screw on connectors BEB. Makes the brickbats worthwhile although I am surprised that you did not delete a couple of particularly vitriolic posts from a member who thinks that banning them in a club is a holier than thou act by the safety officer. The model actually looks OK and practical to me but then I like wierdo ones. Would be interested but the stick in the muds at my club want to ban FPV in general/quads with FPV or not, without even seeing one in action. Anyone wanna buy some quads/goggles/ video Tx`s/5.8Rx`s etc? I really do find that sort of attitude very depressing. We are all basically interested in the same thing - flying machines using radio control. We should be celebrating the breadth and diversity our hobby offers - not excluding people because they don't like exactly the same things we do. I don't like pylon racing, I'm not amoured of gliders, retro-RC leaves me cold - but to paraphase Voltaire "I would fight to the death for your right to do those things"! Well,...perhaps not to the death, but you know what I mean! BEB Quote Link to comment Share on other sites More sharing options...
cymaz Posted March 29, 2016 Share Posted March 29, 2016 Ok, sensible question....is it me or does that look like an enormous amount of down thrust on the motor? Quote Link to comment Share on other sites More sharing options...
Peter Miller Posted March 29, 2016 Share Posted March 29, 2016 Posted by cymaz on 29/03/2016 06:18:36: Ok, sensible question....is it me or does that look like an enormous amount of down thrust on the motor? I was just thinking the same thing. Consider that the motor is lined up with the wings and tail, the main centre of drag, and then we have the massive lower pod producing more drag well below the motor. I doubt if it needs any down thrust at all. Quote Link to comment Share on other sites More sharing options...
Biggles' Elder Brother - Moderator Posted March 29, 2016 Author Share Posted March 29, 2016 I would agree with both of you! This is not a "high wing" plane strictly speaking, despite its looks, as the thrust line is more or less in line with the wings. So I was surprised as well. In fact - given the existance of the lower pod and the fact that that will move the centre of drag well downwards, if I was going to design any alteration in the trustline it would be a hint of up thrust not down-thrust! But its not accidental, the plastic moulding at the front, to which I have bolted my ply mounting plate hard against, is made that way - ie its not just recessed more on one side, or put in wonky, it actually tapers in thickness. This would suggest some considerable effort has been expended to achieve that down-thrust. The plan is to stick with it for now - maiden it and see if it needs to be altered then. I'll get into the Taranis and make sure I have loads of up-elevator trim available!! BEB Quote Link to comment Share on other sites More sharing options...
Biggles' Elder Brother - Moderator Posted March 29, 2016 Author Share Posted March 29, 2016 I have been having an issue understanding how the dome-window fits onto the nose of the lower pod, so I decided that "Google was my friend" and I'd see if there were any hints out there about this. I found this video review - very good I think. Interestingly he does specifically point out the down thrust issue - but leaves it unchanged and, assuming the maiden he shows is genuine first time, it has to be said that the Skua seems to fly very well indeed. 9And yes - it did solve the dome problem - there is a foam collar I hadn't spotted!) BEB Quote Link to comment Share on other sites More sharing options...
Biggles' Elder Brother - Moderator Posted March 29, 2016 Author Share Posted March 29, 2016 OK, bits and pieces done. Here it is all together: And from the front/side... Only job remainng is to find the right screws to fix the wings on! I've tried everything left over - none of them fit, I'll have to have a fiddle tomorrow morning. So, the plan now is to fly this as a conventional RC model aircraft - ie VLOS. That way I can sort out the set up - trim, throws, expo, optium CoG etc. Then we can start fitting the FPV gear. Tomorrow looks a possibility for the maiden, but the forecast gives the winds as 12-15mph. That is a bit high for this model at the moment - without its full size battery and the FPV equipment it is very light. We'll see tomorrow afternoon what its like. BEB Quote Link to comment Share on other sites More sharing options...
john stones 1 - Moderator Posted March 29, 2016 Share Posted March 29, 2016 As a camera platform he gives it a good review BEB John rolls a bit like a P2000 mind Edited By john stones 1 on 29/03/2016 22:37:25 Quote Link to comment Share on other sites More sharing options...
Biggles' Elder Brother - Moderator Posted March 30, 2016 Author Share Posted March 30, 2016 Her she is in my back garden early this morning,... All dressed up and ready to go! Maiden this afternoon hopefully. BEB Edited By Biggles' Elder Brother - Moderator on 30/03/2016 12:17:49 Quote Link to comment Share on other sites More sharing options...
Biggles' Elder Brother - Moderator Posted March 30, 2016 Author Share Posted March 30, 2016 Well its flown! But not without some issues. I was only using a 4000mAh battery - as opposed to the 10,000mAh she is designed for. Also there was no FPV gear on board, so no camera, mount, AP, VRx etc. All of which meant it was considerably lighter than operational weight - and it was quite windy - with a strong cross wind. Result - it flew, but very floaty and it struggled to penetrate into wind (correction, I struggled to make it penetrate into wind!) But in the odd moments when the wind died down she did feel very stable and smooth - if a little "staid" - or as my mate John Stones would say "graceful"! - indeed "hands off" straighta and level flight was possible in these brief respites from the wind which would suggest that the basic trim and CoG etc is good. I could not get it to ROG - the undercarriage simply couldn't cope with the grass. Our strip is overdue its first cut of the year - so it is quite shaggy - and a lot of smaller models are having difficulties. Its possible that with shorter, drier, grass and a bit more weight behind her then she might managed to take off from her undercarriage. But today was a hand launch - from which she flew away very well, so hand launching doesn't seem to be a major issue. Although it might be a bit more of a challenge when she is heavier and the power-to-weight ratio isn't quite so high? OK, we'll pronounce that flight basically a success - in that it does fly, it does seem to be stable, and I think there is a good chance that with a bit more "beef" behind her she will cope with tricky weather better. So, its now time to move on. Next step,...fit the stabilisation/auto-pilot/OSD system - actually I was thinking whilst flying it today that I could really have done with the stabilisation!!. The weather at the weekend looks horrible - so I may be able to make a start on that then. In the mean time I'll post later with some details about the system I intend on using. BEB Edited By Biggles' Elder Brother - Moderator on 30/03/2016 20:00:22 Quote Link to comment Share on other sites More sharing options...
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