Gerry Stansfield Posted September 17, 2008 Share Posted September 17, 2008 Can enyone tell me why the rigging wires on some Bipes are crossed over as [Tiger Moth] where as on th D.H.60 the wire run parallel?. Quote Link to comment Share on other sites More sharing options...
Former Member Posted September 17, 2008 Share Posted September 17, 2008 [This posting has been removed] Quote Link to comment Share on other sites More sharing options...
Gerry Stansfield Posted September 17, 2008 Author Share Posted September 17, 2008 Thanks, Eric, for info: the reason I asked about cross over wires is I have a Tiger Moth which has the wires crossed over, but I am building a D.H.60 Moth the same size,[1/4 scale] but all the info I have on it the wires run parallel, as you say a triangle is more rigid than a rectangle, so crossed over they will be. Thanks again. Quote Link to comment Share on other sites More sharing options...
Bob Cotsford Posted September 18, 2008 Share Posted September 18, 2008 just a guess, but as the Tiger, like the Bucker bipes, has sweepback, I would say that it uses landing and flying wires in a V shape in order to use the top rear cabane strut as a mounting for the landing wires and the front lower spar for the flying wires. This way the triangle formed in plan view is more evenly balanced for the relevant wing so that as well as vertical forces, the V braces the wing against fore and aft forces. take a look attiggie and MothThe DH 60 has noticably less stagger, so the parallel rigging in plan view can be used without a tendancy to pull the lower wingtips forward and the upper backards. Quote Link to comment Share on other sites More sharing options...
Gerry Stansfield Posted September 19, 2008 Author Share Posted September 19, 2008 The rigging wires on the D.H 60 are actually mounted at the wing roots, not on the fuzzy; which makes it unecessary to remove them when folding the wings.they are hinged at the trailing edge and a locking pin is inserted into a fixture on the side of the fuzzy; holding them in place, ive managed to do that with mine after a lot of [head scratching] Quote Link to comment Share on other sites More sharing options...
Simon Chaddock Posted September 19, 2008 Share Posted September 19, 2008 The Moth (and Gipsy Moth) could have their wings folded along the fuselage (a jury strut was required at the front wing spar joint to keep the wings rigid when folded) but the Tiger Moth wings do not fold as the rear spar bolts are not in line due to the wing stagger. The Tiger was designed to a military spec and wing folding was not included.There is this picture of Belgian surplus Tigers with their wings folded back but the concensus is that they were being stored prior to scrapping so the damage to their rear spar mountings did not matter! Quote Link to comment Share on other sites More sharing options...
Gary Binnie Posted October 5, 2008 Share Posted October 5, 2008 Interesting thread, I part-own, maintain and fly a full size Tiger Moth as well as building flying models of them (have a look in my gallery). On the Flair 1/4 scale Tiger the wires are functional (silver soldered).The flying and landing wires on the Tiger actually attach to the wing root ribs, this is a left-over from the earlier Moths with folding wings. I had a close look at a DH60 'Gipsy' Moth recently and was intrigued to see that de Havilland used the same wing fittings! The quick release pins are replaced with a more permanent pin but the rear hinge points (upper and lower) are still there. As Simon says the wing assemblies can not be folded because of the geometry.I've got some close up photos of the fittings if anyone is interested.Often think about those wires when I'm floating along, they do have to be checked and looked after regularly.CheersGary Quote Link to comment Share on other sites More sharing options...
Gerry Stansfield Posted November 3, 2008 Author Share Posted November 3, 2008 Hi, Gary. I would very much like to see your photo's of the wing fixing fittings of the Moth, to compare them with the one's I have made for mine, I have lots of pictures of the DH60 but no close ups of the actual fixings, I only hope mine are strong enough for the job!! The flying wires are fully functional and running parallel to each other, unlike the Tiggy which are crossed, as you will know, part owning one [lucky you], always fancied a fly in on, have to make do with the model! Kind regards, Gerry. Quote Link to comment Share on other sites More sharing options...
Gary Binnie Posted November 3, 2008 Share Posted November 3, 2008 Hi Gerry,They are not as close up as I remember but I can take some more if you need them.1. Lower wing rear hinge fitting and flying wire attachment:2. Upper wing rear hinge fitting, vertical pins at each end of the tube behind the fuel tank.3. General view of the wires:Have not flown for a while (Tiger or models), weather is a lottery this time of year! Cheers Gary Quote Link to comment Share on other sites More sharing options...
Simon Chaddock Posted November 3, 2008 Share Posted November 3, 2008 GaryNice pictures.It always amazes me just how tiny all the fittings are and they take ALL the flying loads. As you say it a good idea to check them once in a while when that is all thats keeping you flying! Quote Link to comment Share on other sites More sharing options...
Gerry Stansfield Posted November 4, 2008 Author Share Posted November 4, 2008 Gary, If you can take some closeups of the rear hinges top and bottom an one of the locking pins I would really appreciate it, thank's, Agree with you about the Weather. Quote Link to comment Share on other sites More sharing options...
Gary Binnie Posted November 4, 2008 Share Posted November 4, 2008 Yes, it is a bit 'thought provoking' when you see what holds it all together, an incentive to do good pre-flight inspections and go easy on the 'G' forces.Will do Gerry, won't be for a little while though (Sqn reunion this weekend and a visit to Duxford, never been).CheersGary Quote Link to comment Share on other sites More sharing options...
Steve biplane Posted November 5, 2008 Share Posted November 5, 2008 The Tiger Moth introduced the staggered wing and change of rigging geometry as a result of the RAF's requirement that the front seat occupant can bail out as easily as the rear. The staggered wing allowed the centre-section wing struts to be moved ahead of the front cockpit. Both the lift and landing wires run to the forward spar position (at the fuselage) so as not to be in the way of the bale-out. I'd be interested to hear Gary's thoughts of the difference/similarities of flying full size and large, quarter scale model Tigers. Steve Quote Link to comment Share on other sites More sharing options...
Gary Binnie Posted November 5, 2008 Share Posted November 5, 2008 Almost!The centre section (cabane struts) went forward for the reason you describe ( a hacksaw and a cigarette packet drawing were involved allegedly!) then the wings had to be swept back to preserve CofG and centre of pressure (lift) relationship. With the tail down this moved the lower rear wing tips quite close to the ground and they often touched on the prototype Tiger during taxiing, the answer was more dihedral on the lower wings (leaving the upper wings untouched) to give more clearance, achieved with a hacksaw again to shorten the interplane struts!The sweepback angle is slightly different on upper and lower wings and another 'fudge' left over from the redesign is that the wing ribs are in line with the leading edge and not the airflow. I've got a KeilKraft plan from the 1950's that has them in line (and a rolled up balsa cement tube shown for nose ballast, remember those tubes?!!)Comparison between models and full size? Quite similar I think, both are very stable in flight and not particularly aerobatic. The full size controls are quite heavy in feel (especially compared to a Chipmunk) . The full size stall is quite benign with the slats out (about 35 knots) but with the slats in it is quite different and will drop a wing and spin quite rapidly if not recovered. Some Tiger's don't have slats (or anti-spin strakes) of course. Rudder needs to be used on both, I usually mix it in with the ailerons on a model.Approaching the stall there is virtually no 'pre-stall buffet' warning which I found quite 'interesting' when I converted to the Tiger Moth, it might be the reason that quite a few have met the ground over the years with the pilot usually walking away wondering what happened! I always watch the airspeed very carefully near the ground, being 'draggy' it is quite easy to slow down without noticing.I think we fly TM models with a slightly forward CofG from the full size position for pitch stability, most of my Tiger models (I think I had five of different sizes at one stage) were very reluctant to stall or spin. This Flair Tiger is very stable but a bit underpowered with an OS FS120, it originally had 2 lbs of lead in the nose, I gradually removed some (but not much) until it would just spin with the right 'provocation'.It has working flying and landing wires which have silver soldered end fittings (standard metal RC servo clevises for adjustment).Sorry about the ugly bloke! CheersGaryThis one was an experiment (rubber free-flight to GWS electric power and radio control conversion), suffered from 'glitching' interference and it is in semi-retirement (thought I'd better before it met a sticky end!) Quote Link to comment Share on other sites More sharing options...
Steve biplane Posted November 5, 2008 Share Posted November 5, 2008 Gary, Thanks for your quick reply and interesting comments re full-size and model Tigers. I've only managed to have one Tiger flight - that came as a complete surprise and was due to winning a raffle at Shuttleworth's several years ago. Best memory from the flight was turning at Cardington and seeing the airship sheds below. I'll be making a DB Tiger Moth over the winter (1/6th size) so it will be interesting to see how it goes together and flies.Steve Quote Link to comment Share on other sites More sharing options...
Gary Binnie Posted November 5, 2008 Share Posted November 5, 2008 Old Warden is a very special place for me, been a visitor since the late 1960's. My dad was a regular on the free flight days, I met fantastic people like Ron Moulton, Howard Boys (a real character), 'Jack' Frost, John Blagg (superb peanut scale), Mick Staples (excellent control line scale builder and flyer) and many others.I have some old cine film of RC Spitfires and a Beaufighter taking off (or trying to) on hardboard runways, there is also a Jet Provost formation team of four aircraft in silver which might date it. Been over in the Tiger a couple of times this year and always feel guilty for temporarily stopping the modellers from flying! Always get a cheery wave though.I have a very distant memory of a pub near Cardington with a ride-on steam railway in the garden, possibly called 'the fox and hounds', does this ring any bells with anyone? Good luck with the DB build, I hope you are going to post a build thread.CheersGary Quote Link to comment Share on other sites More sharing options...
gerald stansfield Posted October 8, 2009 Share Posted October 8, 2009 Spread your wings, and Fly. Quote Link to comment Share on other sites More sharing options...
Ady Hayward Posted October 9, 2009 Share Posted October 9, 2009 Hi, Just a little point. The prop on the Gypsy engine rotates opposite to the model engine and most "Spam Cans". My first attempt at taking off in a Tiger (G-ANEF) was a bit of a weaving line ahead having lead the power application with right rudder and not left!. Re- starting the engine in flight is an occasion too, haviing to push past the vertical to get enough airspeed to turn the prop over......AAAH happy days. Regards Adrian Quote Link to comment Share on other sites More sharing options...
Simon Chaddock Posted October 9, 2009 Share Posted October 9, 2009 AdrianA good point - I wonder how many scale Gipsy engine types have the prop going round the right way. Quote Link to comment Share on other sites More sharing options...
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