Colin Leighfield Posted August 14, 2014 Share Posted August 14, 2014 Definitely not Chris. (I'm hoping that Simon isn't similarly afflicted, having never met him I don't know, pardon me Simon). People frequently tell me that I'm bionic, but I won't disclose the bits they're referring to)! Quote Link to comment Share on other sites More sharing options...
Colin Leighfield Posted August 14, 2014 Share Posted August 14, 2014 As a further thought, perhaps the thread could be re-titled "Arms? What arms"? Quote Link to comment Share on other sites More sharing options...
Simon Chaddock Posted August 14, 2014 Author Share Posted August 14, 2014 I presume there must be limits on the degree of physical disability permitted to hold a commercial pilots licence. I expect in reality he could fly quite as well as anybody else but I suspect Flybe will not be that impressed with all the 'sensational' publicity arising from incident. After this I wonder how many pilots might be tempted to walk through the cabin to the cockpit with one arm hidden inside their jacket! Quote Link to comment Share on other sites More sharing options...
Chris Bott - Moderator Posted August 14, 2014 Share Posted August 14, 2014 I'm sure the pilot has had to convince examiners and employers alike that he's as competent as the next man, probably more so. I bet he's mortified at the publicity, himself. I also bet it was quite a shock to him at the time too, and I'd wager that he'll be absolutely sure that it doesn't happen again. Bad timing for him though wasn't it? Just in the flare, poor chap. Quote Link to comment Share on other sites More sharing options...
Colin Leighfield Posted August 14, 2014 Share Posted August 14, 2014 Flybe say that's he's one of their longest serving most senior pilots with an excellent record and I'm sure that's true. Shame they had to publicise one slightly bouncy landing in which there was no damage or harm done. It's a good job that one of DB's tin legs didn't come off while he was on a "rhubarb" over France in 1941. Or perhaps one did and that's the reason that he got shot down (Sorry! I'm aware of the debate on that one). Quote Link to comment Share on other sites More sharing options...
Rob Lewis Posted August 14, 2014 Share Posted August 14, 2014 Posted by Simon Chaddock on 14/08/2014 16:03:26: After this I wonder how many pilots might be tempted to walk through the cabin to the cockpit with one arm hidden inside their jacket! We were joking about this around the briefing table earlier. Can't really add a comment on the subject, as we've been briefed at work to keep stum, you never know when a journalist may be watching. But its all a mountain out of a mole hill really...... Can't wait to see your Q4 take shape though Simon, watching with interest. Quote Link to comment Share on other sites More sharing options...
Simon Chaddock Posted August 16, 2014 Author Share Posted August 16, 2014 As the fuselage will be purely a stressed skin in 3mm Depron it will need many formers to support it probably every 2" (50mm). At 6.2" (155mm) diameter 30 odd solid sheet circles would use a lot of Depron! My preferred option to save weight and material is to use a 'ring' former preferably in the form of a circular 'I' beam. So a 'test' fuselage former The inner flange is an 8mm x 3mm strip. The ring shear web is 2mm Depron and made up of 8 segments which can be cut economically from a sheet. Strong and light but cutting and gluing together over 240 segments for the 30+ formers is a daunting prospect. I suspect I may have to sacrifice some Depron and use bigger segments maybe just 2 half circles. Edited By Simon Chaddock on 16/08/2014 00:41:20 Quote Link to comment Share on other sites More sharing options...
Simon Chaddock Posted August 17, 2014 Author Share Posted August 17, 2014 I have decided to make the fuselage, at least the long central tube bit, as a half shell over the plan. It is alarmingly big, not quite 78" long.. I now have the props, spinners and motors but with my first problem. The props are 'handed' but of course the spinners are not! The 'conventional' 9x5x3 prop and spinner on my test stand. The 28mm 1200kV out runner is rather dwarfed by the spinner! It took quite a bit of engineering to get it all to fit nicely. Then I came across the next problem. The prop was hopelessly out of balance needing 0.065g at the tip on one blade and 0.012 on the other. This is far more than could be achieved by painting so I had to adopt a "do not try this at home" type solution - lead tip weights! The small hole in the blade is filled with a small piece of lead carefully peened over each end to hold it in securely along with a dab of thin super glue just to make sure. This is the smaller of the two weights. On a 3s it draws 13A at full power showing 147W. If the Q400 comes out anywhere near my guestimated weight it should have close to 150W/lb. Edited By Simon Chaddock on 17/08/2014 20:46:23 Quote Link to comment Share on other sites More sharing options...
Simon Chaddock Posted August 19, 2014 Author Share Posted August 19, 2014 After much cogitation at last a modest start of the tube part of the fuselage. Hows that for an untidy bench! The vertical pieces are jury struts that will be removed once it is fully skinned except under the wing where they will be replaced by a more complex load bearing set of struts to resist the belly landing shocks from the very heavy wing. Edited By Simon Chaddock on 19/08/2014 11:10:52 Quote Link to comment Share on other sites More sharing options...
Colin Leighfield Posted August 19, 2014 Share Posted August 19, 2014 The route to a complex but consequently very light and strong structure. Are you counting the man-hours Simon? Quote Link to comment Share on other sites More sharing options...
Simon Chaddock Posted August 19, 2014 Author Share Posted August 19, 2014 Colin If I counted the man hours I would give up long before I finished.! The first fuselage planks. I am trying a slightly different method of glueing them on using POR to stick the plank to the former but leaving the joint to the adjacent plank dry Super glue is then wicked into the joint. This should allow the plank joint to be satisfactorily sanded whereas a POR joint is almost impossible to sand well. Quote Link to comment Share on other sites More sharing options...
Colin Leighfield Posted August 19, 2014 Share Posted August 19, 2014 Another piece of build wisdom duly noted! Quote Link to comment Share on other sites More sharing options...
ROY DAVIES 1 Posted August 19, 2014 Share Posted August 19, 2014 I am not sure that this has got a supercritical wing like the ATR and the Dornier 228. I can envisage a deep stall scenario if the correct angle of attack is held with a bleed off in speed or increasing drag on the climb out. Quote Link to comment Share on other sites More sharing options...
ROY DAVIES 1 Posted August 19, 2014 Share Posted August 19, 2014 Every time I handle Depron it snaps Your a Hero Good luck. I have a kit YS11 to build it's in a box for the moment, it's had 2 birthdays already ! Quote Link to comment Share on other sites More sharing options...
Simon Chaddock Posted August 19, 2014 Author Share Posted August 19, 2014 Roy Most of my Depron scale planes have scale wing sections right down to sharp edged very then supersonic ones. At the very low Reynolds numbers they fly at the drag is relatively high anyway and the stall is much less dramatic than on full size. I suspect the biggest issue will be simply running out of elevator authority at high angles of attack due to the T tail being blanketed by the wing. Quote Link to comment Share on other sites More sharing options...
ROY DAVIES 1 Posted August 19, 2014 Share Posted August 19, 2014 The Staines deep stall accident comes to mind. But I was at Farnborough when the Buffalo crashed and was standing just downwind of the crash spot. The aircraft did a descending spiral to the right at about a 30 deg' angle as he turned to square up with runway his rudder as well as his elevator were waving about like flags (in fact the whole fin post assembly was shaking in the turbulence generated by the top of the wing), to no effect so he could not effect a flair and plonked it on the tarmac with bits flying every where. 'So the rudder don't work either if it aint in a draft' I worked for a company that weighed/s most of these and it was quite a critical set up to make sure the longitudinal level was spot on as the moment arms are so long. There is a plumb bob point above the rear st'b'd door frame and cill. Quote Link to comment Share on other sites More sharing options...
Simon Chaddock Posted August 20, 2014 Author Share Posted August 20, 2014 The planked half shell nearly complete. I had not intended to use grey but this part of the fuselage is over 1m long so it needed a 1250mm 3mm Depron sheet which is only available in grey. The real test is getting the half shell off the plan and seeing if it remains straight and true. It looks twisted in this picture but it isn't. Its all down to the camera! The extra former and internal sheeting is to locally reinforce the fuselage under the wing. It is also where the fuselage will be gripped for a hand launch. Slow going but its getting there. Edited By Simon Chaddock on 20/08/2014 23:30:43 Quote Link to comment Share on other sites More sharing options...
Simon Chaddock Posted August 22, 2014 Author Share Posted August 22, 2014 Adding the formers to create the other side is slow going. First the half former is added to complete the ring. Then a flange in added to the former inner circumference to form an "I" beam. Fiddly as it has to be exactly the right length to ensure it touches the former all the way round. Then a flange is added to the lower keel between the formers so it too becomes an "I" beam to better resist belly landing loads. Finally a 'jury' strut is added to keep the former square. They will only be removed once the planking is about 3/4 of the way round. Access limitations mean each former must be complete before starting work on the next. About 5 an hour is the best I can achieve and there are 23 to do! Then there are 16 planks to be added and it will still only be the central part of the fuselage! Edited By Simon Chaddock on 22/08/2014 17:59:07 Quote Link to comment Share on other sites More sharing options...
Simon Chaddock Posted August 26, 2014 Author Share Posted August 26, 2014 This is rather slow going but the formers are at last complete. So far it has taken 154 individual pieces of Depron! There are 16 more (planks) to go. Quote Link to comment Share on other sites More sharing options...
Colin Leighfield Posted August 26, 2014 Share Posted August 26, 2014 Amazing. (To say nothing of your patience Simon). Quote Link to comment Share on other sites More sharing options...
Simon Chaddock Posted August 26, 2014 Author Share Posted August 26, 2014 I got bored doing fuselage planks so I moved over to an engine nacelle as I have to do two of them! After studying many pictures the nacelle has quite large flat areas and best of all it's underside is a straight line!. At just over 16" long it would not be out of place as the fuselage on a small park flyer. All 3mm Depron as a stressed skin monocoque. The only wood will be the motor bulkhead. The complex bits to form will be the area round the air intake and the exhaust particularly as they will be functional for cooling. Quote Link to comment Share on other sites More sharing options...
Rob Lewis Posted August 27, 2014 Share Posted August 27, 2014 For a build you weren't even sure you were going to start its coming on fast. Excellent work, still watching with interest. Quote Link to comment Share on other sites More sharing options...
Simon Chaddock Posted August 27, 2014 Author Share Posted August 27, 2014 A bit more progress but I am having to make this up as I go along! The flat nacelle underside goes on. The motor bulkhead and drum mount. The ESC will be mounted low down in the airflow from the intake. A test mounting of the motor with prop and spinner. A 12 mm thick Depron 'nose block' will fair in the nacelle to the spinner and also create the mouth of the air intake - well that the plan! Quote Link to comment Share on other sites More sharing options...
Simon Chaddock Posted August 29, 2014 Author Share Posted August 29, 2014 The last plank of 33 or rather the space to be filled!! Always the hardest as it has to be accurately shaped to fit along its entire length and on both sides. Next the cockpit section. Quote Link to comment Share on other sites More sharing options...
Colin Leighfield Posted August 29, 2014 Share Posted August 29, 2014 Keep going Simon - - - - . This is going to look good. Quote Link to comment Share on other sites More sharing options...
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