Andy Hat Posted October 25, 2015 Share Posted October 25, 2015 This Precedent Fly Boy was mostly assembled in the early 90s, put in the loft, and only recently finished off. It was built for IC and I converted it to electric as I finished it. Today it had the maiden flight and, although it's not smashed up, the flight was very scary. It was climbing, almost prop-hanging, and all over the place. At one time, it flipped upside down. It cartwheeled in after I cut the power and the only damage was a stripped rudder servo and a slightly crushed wing root. When it was 'flying' it felt possibly tail heavy but something/s need changing before I try again. The CG is as specified and the throws are those recommended in the instructions. I've read (probably on here) that they can be difficult to fly. It may have been one of the planes mentioned in a worse-plane-ever-thread. I think I've also read that someone had to pack up the rear of the wing to make it fly? Any suggestions most welcome! (Motor 3536/1050kv, battery 2200mah 3S, prop 11x5.5) Quote Link to comment Share on other sites More sharing options...
Steve Fisk Posted October 25, 2015 Share Posted October 25, 2015 Funny you should mention this but I was in the loft earlyer thinking about getting it down and finishing it off to fly , wonder why it was so bad to fly then ? I was thinking electric to Quote Link to comment Share on other sites More sharing options...
Don Fry Posted October 25, 2015 Share Posted October 25, 2015 Nothing wrong with them, sold in their thousands. If the centre of gravity is right, check thrice, and properly, no two fingers under the wing, you have too much up trim on the elevator. Try 4 to six 360 degree turns shortening the elevator push rod, i.e. clockwise from behind. Game of blood I'm afraid, unless you employ a maiden flight tester. But if you survived once, the above should, God's willing, get you down in one piece. They who rubbish them are in the failure camp, blaming their tools. Mind, they are heavier than modern trainers. Perhaps less forgiving, certainly stronger, but also a better plane in a wind, so you get more days on the sticks. Quote Link to comment Share on other sites More sharing options...
Don Fry Posted October 25, 2015 Share Posted October 25, 2015 Reading your post again, make shire that the thrust lines of the leccy conversion are correct. Possible that the moter is angled too much up. These things ran on a 40 2st. Believe they finished before leccy was invented. Quote Link to comment Share on other sites More sharing options...
Alan Gorham_ Posted October 25, 2015 Share Posted October 25, 2015 I think Donald is confusing this model with the larger Precedent Hi-Boy which was a good flyer and did sell many kits. Andy, you've made a splendid job of the Fly Boy, but, yes it did have a reputation as a tricky flyer. It certainly had a heavy wing loading which didn't help. My first question to you is have you flown rudder/elevator models before? The flying technique is subtly different to flying a model with ailerons and this might be worth checking... Otherwise, assuming your CG is placed at 25% of the wing chord, I would be looking at your wing and tail rigging angles, wing warps and thrustlines. Quote Link to comment Share on other sites More sharing options...
Andy Hat Posted October 25, 2015 Author Share Posted October 25, 2015 Thanks Donald. The thrust line of the motor is exactly the same as the engine bearers that I cut away. I got my CG Machine out and found that I needed to add 30g to the front to make it just (very slightly) nose heavy. You were right - the finger tip method wasn't accurate. I'll wind down the throws a bit and try again soon. I'll post here and let you know how it goes. Steve - you should definitely get it out and finish it! Quote Link to comment Share on other sites More sharing options...
Andy Hat Posted October 25, 2015 Author Share Posted October 25, 2015 Thanks Alan. I'm glad I bought the stripe sticker at the time. Yes I've flown a few 3 channel (no aileron) planes before. I am probably considered to be the main maiden-flight-tester at our club which is why this one took me by surprise - and I built it! It's pretty straight and weighs just under 1300g ready to fly (with battery). I'll be a bit more careful next time - it probably is overpowered. Quote Link to comment Share on other sites More sharing options...
ted hughes Posted October 25, 2015 Share Posted October 25, 2015 I had one of these years ago. It was like an flying brick. Quote Link to comment Share on other sites More sharing options...
Simon Wright Posted October 25, 2015 Share Posted October 25, 2015 I had one way back when as my first IC trainer. ( I learned to fly on the Electra-Fly sp600, 8x4 and 7 x sc1700) Fitted with an OS15FP, remember that it was unable to ROG in my hands but I solo launched it okay and it flew fine, although I had no baseline to measure against. Quote Link to comment Share on other sites More sharing options...
onetenor Posted October 26, 2015 Share Posted October 26, 2015 If I recall correctly 3 degrees more down thrust cured mine although it was heavy. I did crash it and I built a new fuse for it using smaller dimensioned wood sizes and lighter stock. It behaved much better after but still needed that 3 degrees extra down thrust. I think the supplied =bearers were set at 0 degrees and I had to put washers under the rear of the mounting lugs for the required thrustline I also reset the tailplane 1/16th higher at L.E. These changes seemed to do the trick for me anyway. Try them and see. Quote Link to comment Share on other sites More sharing options...
Cuban8 Posted October 26, 2015 Share Posted October 26, 2015 When I was heavily into training new fliers 25-30 years ago, I recall that the Fly-boy and its bigger brother the Hi-Boy were very common and successful trainers. However, they weren't easy to fly by a raw beginner and did need to be set up correctly before they'd perform well. Try to fly either on your own as a beginner or rush the setup and rekitting was inevitable. As has been said they were designed to be robust and this did make them a bit on the heavy side compared to what beginners are used to today. The benefit, of course, is that you rarely finished up with a heap of unrepairable matchwood as is the case with ARTF wooden trainers after a crash, and you did manage to fly when it was breezy. Test flown by an instructor and set up correctly, I found the FB and HB excellent trainers Funnily enough I don't recall them to be overly sensitive to CG position - usually 25-30% of wing cord would do it and usually balanced on the fingers in time honoured tradition. I do recall that control throws needed to be set carefully, the rudder on the Fly-Boy being very powerful especially with motors at the higher end of the power range - the model would easily barrel roll given full rudder. No more than 1/2 inch either way for general flying IIRC and a bit less for a beginner. The HB needed a decent motor to give of its best and performed well with CG at the 25% mark - take off runs would be fairly extended giving the trainee experience of keeping the model straight on the ground and naturally the model needed to be flown right to touch down and roll out. Not a bad thing really, and stood newbies in good stead when it came to flying much more challenging aircraft later in their modelling careers. The Precedent trainers did get a reputation for being tricky, but I prefer to think that they actually taught a beginner more effectively than many of the much lighter models available at the time, as when incorrectly handled they could bite, although with a buddy-box this could be used to advantage. Just wondering whether modern lightweight, ready to fly, auto stabilized, panic buttoned, electric trainers are making it all too easy and taking away the euphoria of getting a challenging model to succumb to one's will? Edited By Cuban8 on 26/10/2015 08:14:59 1 Quote Link to comment Share on other sites More sharing options...
Biggles' Elder Brother - Moderator Posted October 26, 2015 Share Posted October 26, 2015 I had a Hi-Boy years ago. Yes it was heavy, but it was also solid and as said would fly in a wind! I wasn't much of a judge at the time but I thought it flew fine and loved it! One think it did do was teach you how to manage the model's energy - if you could deadstick the Hi-Boy well you knew you had it cracked! One thing that bothers me a bit these days is so many learners turning up with ultra light-weight foamies. They learn to fly them OK, but when they move on to something heavier - often much heavier! - they really struggle to come to terms with the momentum. Weight isn't usually a good thing in any model but with trainers it does have its good points! I don't think I've ever flown a Fli-Boy and by the sound of it I might not want to! BEB Quote Link to comment Share on other sites More sharing options...
Andy Hat Posted November 2, 2015 Author Share Posted November 2, 2015 Thanks to the help on here, I got it flying! I reduced the rudder throw a lot and added some more downthrust. I did find that I had to add a lot of down on the elevator to make it fly straight but I managed a number of flights. Not sure if it's a characteristic of rudder/high-dihedral only planes but it takes some effort to initiate a turn or roll. Once it's gone past a few degrees then it 'falls' to the side a bit easier. Taking off from the ground isn't pleasant because if you use the rudder to keep it tracking straight, it always violently rolls just as it takes off. A hand launch looks much more professional. I might try adding some more weight to the nose - I don't like it having lots of down elevator just to fly straight. It needs a bit more downthrust too since it climbs a lot under power. I tried packing up the back of the wing but it just seemed to make it less responsive on the rudder. Still, it was nice to see it flying around against a clear sky, after it spent 20 years in pieces up in the loft. Quote Link to comment Share on other sites More sharing options...
rcaddict Posted November 2, 2015 Share Posted November 2, 2015 I learned to fly on the hi-boy (bigger brother), it was a great trainer, Funny enough I still have precedent models in the loft fun-fly, T180, low-boy. - all excellent fliers did the hi-boy not have built in thrust on the plywood engine mount setup I think some of the precedent kits are still made by Slec - I think !! Quote Link to comment Share on other sites More sharing options...
AJ Posted November 2, 2015 Share Posted November 2, 2015 Taught myself to fly on the hi-boy, took me 3 kits and numurous rebuilds before I sucessfully landed one. Eventually moved onto the lo-boy which I flew for many years. Nice models but definetly on the heavy side. AJ. Quote Link to comment Share on other sites More sharing options...
gangster Posted November 3, 2015 Share Posted November 3, 2015 I have no experience of the Fly Boy but if I recall it is a fair bit smaller than the Hi Boy. If that is the case you seem to have a lot of power available with that set up. Does it settle down a bit more at low throttle? If so maybe reduce the power a bit. And as well as that you might benefit from mixing down elevator with the throttle. Quote Link to comment Share on other sites More sharing options...
kc Posted November 3, 2015 Share Posted November 3, 2015 To say that the Hi Boy is the bigger brother of the Fly Boy seems quite wrong even though they came from the same maker and designer. Fly Boy has a flat bottom wing section while the Hi Boy is symetrical. Quite different flight characteristics and the Hi Boy is far superior. Quote Link to comment Share on other sites More sharing options...
john stones 1 - Moderator Posted November 3, 2015 Share Posted November 3, 2015 Yep yesterdays trainers where a bit heavier, only have fond memories off em myself John Quote Link to comment Share on other sites More sharing options...
Cuban8 Posted November 3, 2015 Share Posted November 3, 2015 Posted by Andy Hat on 02/11/2015 21:48:02: Thanks to the help on here, I got it flying! I reduced the rudder throw a lot and added some more downthrust. I might try adding some more weight to the nose - I don't like it having lots of down elevator just to fly straight. It needs a bit more downthrust too since it climbs a lot under power. I tried packing up the back of the wing but it just seemed to make it less responsive on the rudder. All good experience that the new 'foamy generation' of fliers are missing out on IMHO (nothing fundamentally wrong with foamies, of course). Quote Link to comment Share on other sites More sharing options...
john stones 1 - Moderator Posted November 3, 2015 Share Posted November 3, 2015 I agree with C8 all good experience that'll come in useful when building and flying more complex models, you might be suffering from just having too much power available, hence the need for more downthrust, maybe propping motor down a bit would help. John Quote Link to comment Share on other sites More sharing options...
Engine Doctor Posted November 3, 2015 Share Posted November 3, 2015 Great fun if you could fly but not a confidence builder for a beginner as I remember. Buddy lead teaching was not as common then and trying to prise the tx out of a students hand while the Fly Boy was trying to re kit itself was a regular nightmare . The model wasn't heavy but the radio gear etc of the day turned it into a brick. The Hi Boy ,having a bigger wing area could handle the weight easily and was a sturdy trainer that could handle windy conditions easily. Quote Link to comment Share on other sites More sharing options...
Skankster Posted October 16, 2017 Share Posted October 16, 2017 Hi, I've just been looking at a fly boy in my attic that I started many years ago, I had modified the wing to ailerons and now I'm thinking of finishing is off but I too would like to make it electric powered any hints would be great as I have pretty much no knowledge of electric power Quote Link to comment Share on other sites More sharing options...
Skankster Posted October 16, 2017 Share Posted October 16, 2017 Hi, I've just been looking at a fly boy in my attic that I started many years ago, I had modified the wing to ailerons and now I'm thinking of finishing is off but I too would like to make it electric powered any hints would be great as I have pretty much no knowledge of electric power Quote Link to comment Share on other sites More sharing options...
Robin Etherton Posted October 16, 2017 Share Posted October 16, 2017 In my early 30’s the hi boy was my first introduction to radio control flying. Although I belonged to a club(Cosmo) you were more or less left on your own in the actual learning to fly. It’s true the hi boy was a very solid build (brick) but would stand a great deal of punishment. I spent three weekends unsucessfully trying to get up enough ground speed to get off the ground. It went like this , open throttle, move forward, get into a speed wobble, attempt take off, roll into the deck, pick up pieces go home and repair and the repeat. Eventually I spent one whole weekend just speeding along the ground without attempting to take off until I could get the whole length in more a less a straight line. A great sense of achievement when you actually get a successsful take off. Fond memories. Great trainer. Robin Quote Link to comment Share on other sites More sharing options...
J D 8 Posted October 16, 2017 Share Posted October 16, 2017 I have a hi boy hybrid used now an then as a flying engine test beD, It's a hi boy fuzz with the wing of a Rojair cadet 62. Anyone remember them ? Quote Link to comment Share on other sites More sharing options...
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