daza Posted July 18, 2016 Share Posted July 18, 2016 Pilot infront of wing engine behind via prop shaft, Ala P39 Airacobra p39 - Google Search The trouble with mid-wing is you have the wing spar going fair through the cockpit - the Vampire gets away with this as the pilot would be just forward of the main spar to balance the weight of the rear-facing engine, but I'm not sure how it'd work for a tractor design. (I'm sure there's a way, there are plenty out there!) Link to comment Share on other sites More sharing options...
bexrbetter Posted July 18, 2016 Author Share Posted July 18, 2016 Pilot infront of wing engine behind via prop shaft,Ala P39 Airacobra p39 - Google Search Set weights and one pilot (of pretty much insignificant weight too), eg; not people getting in and out of all different sizes and one or two people at that and with or without baggage etc. So no. I would be more interested in front engine, propshaft to rear prop, easier to balance (2 seater), safer, quieter etc. Link to comment Share on other sites More sharing options...
Blueadventures Posted July 18, 2016 Share Posted July 18, 2016 Pilot infront of wing engine behind via prop shaft,Ala P39 Airacobra p39 - Google Search Another is the Stemme S10 motor glider with a rotax behind the cockpit and shaft to forward mounted propeller. Link to comment Share on other sites More sharing options...
Marty_d Posted July 18, 2016 Share Posted July 18, 2016 Probably a moot point, but if the seats backed right onto the spar then most of the pilot/passenger weight is very close to CG anyway. This is where electric would be handy - motor is reasonably light, so no lengthy prop shafts, and all the weight is in batteries which can be distributed around to balance the plane. Link to comment Share on other sites More sharing options...
fly_tornado Posted July 18, 2016 Share Posted July 18, 2016 triplane = triple the batteries 1 Link to comment Share on other sites More sharing options...
onetrack Posted July 19, 2016 Share Posted July 19, 2016 O.K., let's stop all this sidetracking, and get to right to the spec we all want to know - just how fast is this thing going to be, with say, 100HP pushing it, Bex? Are we looking at at something that is going to give a Swiss Risen a run for its money? - or is it just going to be a whisker faster than a Cub? Lots of people need to know this urgently - the amount of notes you can hear being rustled, will increase exponentially for every 10kts increase in promised design cruise speed, over your average ultra-light. 1 Link to comment Share on other sites More sharing options...
bexrbetter Posted July 19, 2016 Author Share Posted July 19, 2016 O.K., let's stop all this sidetracking, and get to right to the spec we all want to know - just how fast is this thing going to be, with say, 100HP pushing it, Bex?Are we looking at at something that is going to give a Swiss Risen a run for its money? - or is it just going to be a whisker faster than a Cub? Lots of people need to know this urgently - the amount of notes you can hear being rustled, will increase exponentially for every 10kts increase in promised design cruise speed, over your average ultra-light. At last calc it was 220 knots, 180 meters landing/TO, and 78 miles to the gallon. Tow rope included to help any Mates with a Risen to keep up. 3 8 1 1 Link to comment Share on other sites More sharing options...
rgmwa Posted July 19, 2016 Share Posted July 19, 2016 At last calc it was 220 knots, 180 meters landing/TO, and 78 miles to the gallon. Tow rope included to help any Mates with a Risen to keep up. Cheque's in the mail Bex! Don't worry about the tow rope. He wasn't much of a mate anyway. rgmwa 2 2 Link to comment Share on other sites More sharing options...
bexrbetter Posted July 21, 2016 Author Share Posted July 21, 2016 So with my hand a bit crook and the stinking humid hot weather we have had for a week (normal this time of year, not GW!), updates have been sparse because I have been doing a lot od CAD work instead at home. I did manage to get a tail post done though, this is a test one, not the final but similar ... 7 Link to comment Share on other sites More sharing options...
Pilot Pete Posted July 21, 2016 Share Posted July 21, 2016 Is this a nose wheel design? Can't remember Link to comment Share on other sites More sharing options...
bexrbetter Posted July 22, 2016 Author Share Posted July 22, 2016 Is this a nose wheel design? Initially yes, it's a real pilot's plane. I can do a goggle and scarf wearing Errol Flynn wanna-be version later. 1 1 Link to comment Share on other sites More sharing options...
SDQDI Posted July 22, 2016 Share Posted July 22, 2016 Initially yes, it's a real pilot's plane. So what you are saying is "Yes, but No" ? 3 Link to comment Share on other sites More sharing options...
Pilot Pete Posted July 22, 2016 Share Posted July 22, 2016 Was just thinking that a mounting plate at the rear post area to accommodate a tail wheel would be in order but it's not. Was just thinking out loud. Continue miestro....... Ps.... Looking good by the way Am really interested in that wing fold mechanism Link to comment Share on other sites More sharing options...
bexrbetter Posted July 22, 2016 Author Share Posted July 22, 2016 Am really interested in that wing fold mechanism So am I, as it goes, often the simpler something is the harder it is to perfect - it's all in the detail and that detail is taking time. Mind you, the basic foundation shown above hasn't changed. Link to comment Share on other sites More sharing options...
bexrbetter Posted July 22, 2016 Author Share Posted July 22, 2016 Was just thinking that a mounting plate at the rear post area to accommodate a tail wheel would be in order but it's not. Would take 2 seconds to add it. I am also figuring out my tail'dragger anti-spin setup, I see a locked wheel drive between the 2 fronts that can be decoupled for maneuvering as one answer. 1 Link to comment Share on other sites More sharing options...
bexrbetter Posted July 23, 2016 Author Share Posted July 23, 2016 The main reason that I haven't done any sheeting on the frame yet is because nothing is set in stone and I am concerned about knocking the panels around during development and needing to replace them. However a few items to do with the tailfeathers requires that the sheets are designed in as well so today I drew up a test sheet and cut it from some cheap steel sheet just to check fitment before I commit to an aluminium sheet that I don't want to waste, happy that it fitted perfectly first time ... Oh and an aluminium sheet is usually 1220 x 2440, cheap gal steel sheets are 1000 x 2000 hence the gap at the rear you see. 2 Link to comment Share on other sites More sharing options...
onetrack Posted July 23, 2016 Share Posted July 23, 2016 Bex, that tail post looks a little flimsy to my untrained eye. Seems like it needs more metal depth, front-to-rear. Remember the Lovebird crash (VH-UGF)? That was caused by useless Oregon timber. The rudder post collapsed, and the result wasn't nice. My recommendation is to steer clear of any Oregon in the build. Well, maybe you could have Oregon trim around the instrument panel. 'PLANE CRASH. - Grave Statement at Inquiry. BROKEN RUDDER POST. TEMORA, Tuesday. - The Sydney Morning Herald (NSW : 1842 - 1954) - 29 Jul 1931 Link to comment Share on other sites More sharing options...
bexrbetter Posted July 23, 2016 Author Share Posted July 23, 2016 Bex, that tail post looks a little flimsy to my untrained eye. Seems like it needs more metal depth, front-to-rear. I am very wary in these critical areas and happy to add a bit of weight, it is well over requirement and probably double the weight it could be. Please bear in mind that it is also part of an integrated, complete structure and can't be judged on it's own. 1 1 Link to comment Share on other sites More sharing options...
AussieB1rd Posted July 23, 2016 Share Posted July 23, 2016 and cut it from some cheap steel sheet just to check fitment And not a Cleco in sight Link to comment Share on other sites More sharing options...
bexrbetter Posted July 23, 2016 Author Share Posted July 23, 2016 And not a Cleco in sight No holes in the frame at all, only in the test sheet. Was a perimeter fitment check and vertical brace hole alignment check. A couple of riveted tabs to the sheet bent over the top frame tube and a G'clamp. I then used a black texta to mark the frame through the holes in the sheet to see where they lay. Not rocket science. Link to comment Share on other sites More sharing options...
Yenn Posted July 25, 2016 Share Posted July 25, 2016 Thats a bit harsh to condemn Oregon timber. Oregon is approved for aircraft manufacture, but there are rules to follow. I have used Oregon in some situations and it is as good as sitka spruce. It all depends upon the quality of the Oregon or Spruce. Another approved timber is Hoop Pine, home grown in Qld. The big thing with timber is to be aware of its quality, whereas you can use aluminium with much greater ease of quality control. 1 Link to comment Share on other sites More sharing options...
Litespeed Posted July 25, 2016 Share Posted July 25, 2016 keep up the great work Bex. And be careful with the damn angle grinder. They can be a precise surgical instrument in the right hands or a super quick way to remove body parts- esp. with a diamond blade. I reckon such a blade could take a finger before you noticed. I hope you don't have a chainsaw. 2 Link to comment Share on other sites More sharing options...
Marty_d Posted July 25, 2016 Share Posted July 25, 2016 I hope you don't have a chainsaw. ...and if he does, I hope he doesn't use it for aircraft building. 1 Link to comment Share on other sites More sharing options...
Methusala Posted July 25, 2016 Share Posted July 25, 2016 G'day Bex, I note the statement in your post #309, that IYHO the hot weather is,"(normal this time of year, not GW!)". How can you be sure of the cause of any weather phenomenon these days? Can it be that you believe the deniers of Global Warming (since de-alarmed to read Climate Change). Nice bit of propaganda there Mr Murdoch? Perhaps reading the following article will help. The unfolding water crisis at the Third Pole Link to comment Share on other sites More sharing options...
bexrbetter Posted July 25, 2016 Author Share Posted July 25, 2016 ...and if he does, I hope he doesn't use it for aircraft building. I use a circular saw for thicker, long cuts actually, not a joke. How can you be sure of the cause of any weather phenomenon these days? I noted it to avoid this type of reply and it's backfired on me, my mistake, my apologies. 1 Link to comment Share on other sites More sharing options...
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