The only comparison I can make, yet again with my model heli's, is that learning to fly mine with it tethered was much harder than allowing small hops across the field. I also had the benefit of two wooden rods forming an x under the heli to widen the footprint and thus stop it rolling over. My thoughts would be in the middle of a nice big field, and then do small hops till you manage to hold it in a steady hover.

Good luck.

Si

I think it is best to slowly pull it off about 1 inch and then set it right back down before it starts to move sideways or backward. Keep doing that until you can hold a 1 inch hover without moving. Then go a bit higher.

But I am no expert. Expert instruction would help.

Bournmouth , I see that pic has the provisions for the optional radome :ok:

Nice design!
Why have you changed the previous round Tailboom to a square section tailboom?

And don't listen to those who've never flown microlights - they're not used to real flying or minimum standards.

Happy New year and the best of luck.

Rigga

Hey rigga, 'Minimum Standards'?? Wanna bet? PMSL

May I hover it?

I'm only up the road, Halesowen. Got a PL(H).

Cron

balls
 

hi !

I owned and flew the deathtrap revolution mini 500 !
If somebody knows what he is doing experimentals can be ok.
but said that, i did not know what is was doing, had just 70 hours and fortune to fly the mini a couple hours and then sold it to complete my CFI.
the mini`s with a turbine must be a blast :} !

fly safe - happy new year !

Rick

Bug, Have any of the previous bugs flown?

I watched a homebuilt hover around a field a few years ago. I seem to recall it had a Yamaha 2 stroke bike engine and flew well till it lost a tail rotor blade!:eek: - no one hurt. I dont know if the builder was a Ppruner - I think he might he may have been called Julian. He might be able to help if anyone on here knows who he is and can put you in contact.

Like others I am curious to know why belts were chosen over shaft and gearbox for the TR when youve got the power to lift the extra weight. That said, I dont think the Rotorways have too many problems with a belt drive TR.

Cheers.

BTW, I have flown a few machines over the years straight after major overhauls, rebuilds, crash repairs etc. (certified only). I do it from concrete to reduce the chance of a skid digging in if it starts to go pear shaped. I'd rather rotate or slide sideways than roll over. Spend some time with it at flying rpm and no collective pitch, check the disk moves as expected with cyclic input. Check the tip plane of the blades is not split. Pedal inputs should cause the aircraft to move slightly, again as predicted. You can feel the thrust just twisting the aircraft a bit. When happy,apply a little collective to get light on the skids and check the pedals make sense again. Check the tip plane of the MR blades. If they split with added collective pitch expect vertical bounce in the hover. This is best checked with a strobe and tip targets. Be very careful with cyclic inputs when light on the skids. Be prepared to dump the lever. When happy, go light on the skids to get TR thrust balanced and pull into a low hover. Be prepared to dump the lever. Take it carefully. Probably best to practice this quite a bit and get it hovering right before moving on to any other tests.

Over the years, I have come across assembly, rigging and tracking and balancing problems with aircraft straight out of maintenance. So far the above technique has worked and nothing has got damaged. Its pretty obvious if its not right. The test is aborted and the problem solved. Others may do it differently but this works for me.

Are my balls big enough for the bug? I might hover it but after that you're on your own.

Best of luck.
Phil

I have five radio control helis, and the least of them looks more formidable and complicated that that machine. Seriously though, if its been checked its got to be as safe as any other machine. Dont tell me that professional heli pilots are falling into the civvy assumption that larger is safer?

"we breed 'em tough and fearless here"
 

Bug - Love your attitude!! Go for it man, and as for "...or should i go for the full monty and just grit my teeth?" Grit your teeth, but for goodness sake, don't get carried away and do something you may later live to regret (or worse, you don't live to regret)!! I'd spend a looooong time at a very looooow hover and doing lots of very gentle manoevres before ding anything that could really bite you.

Best of luck with it - would love to come and help if you need another pair of hands!

TTB

Bugdevheli - I can see where the belt design does have major advantages regarding weight saving, and elimination of the gearboxes, driveshafts & universal joints. I would trust that the belts are aviation grade Kevlar, and not automotive grade.

Belt whip is something that probably needs to be addressed - the distances between the pulleys are quite long, and to eliminate dangerous whip, there are only two ways to do so. One way is to increase belt tension substantially - thus leading to belt stress, shorter life and increased likelihood of failure. The second way is to add idler pulleys to control whip. A third way would be to increase the number of pulleys overall, and thereby reduce the individual belt lengths.

Does this thing actually get off the ground? I haven't seen a video of it actually hovering. I don't believe that too many previous test hovers of chopper prototypes, saw them tethered. Tethering seems like it would place outside forces on the chopper that could lead to incorrect presumptions of stability. Far better to let it fly free, and gather inputs that precisely reflect true flying conditions.

My last question is - what are the plans for a proper fuel tank? - and wouldn't this thing have a very limited range? The weight penalty of a decent fuel tank would seem, to me, to be a big bugbear in the design.

Rigga - From an engineering viewpoint, square sections have vastly increased strength over round sections, when it comes to load-carrying capacity. The sharp corners of a square profile increase strength enormously over the simple round section.

P.S. I've got a thick skin, feel free to savage me all you like, if you feel my comments are too critical. I'm trying to offer constructive criticism, but different people have varying opinons, as to when constructive criticism ends, and destructive criticism starts.
I must say I agree with BoeingMEL, you cerainly look like an old and bold pilot to me. Good luck.

"and wouldn't this thing have a very limited range?"

Its range potential is a moot point as it won't be doing anything more than hovering and maybe a sly CAA unaware circuit, IF anyone's brave enough.....

Please correct me though if you know better and think it would be issued a Permit to Test....

PD

The photo with the rather splendid little heli bug being under the "Deutsche SeeKonig" gives a good example of just how small small really is, the tail rotor of the SK is much much larger than the main rotor on the Bug.

But I still think I would have enough joules to slightly unstick from terra firma, done with much deftness I am sure the traits for such a tiny thing would soon be learnt, after all if most of us can fly the R22 then we are already used to twitchiness in the extreme, I think wind speed and gusts would prove the greatest area of problems for one so small.:eek:

Peter R-B
Vfr

I note that the main concern has been dealt with ... the BROWN corduroys!!!:E:E

Do not tether it !!!!!!
 

Tethering it will cause more problems than its solves.
I own and fly fullsize but have flown dozens of my own model helicopters in the early years when power/stability were big problems.

A good idea for first flights would be to simply increase the width of the undercarriage [sideways and for/aft] with lightweight beams to prevent rollover. pref with rollers at extremeties.

Good luck. Dont like the idea of belt drive to tail however. Never good on models. Shaft drive only way for power and reliability.

OOW

Onetrack

Is that true? Most of the super structures built today use round tube over box section, including the new rooves over Wembley stadium and Wimbledon, as well as the 2012 Olympic stadium. I'm not an engineer, but if square section is stronger, why don't all helis have box setion tails :confused:

TTB

Comparing round and oblong beams, I though "total strength" (all directions) was unchanged but whereas round has equal resistance to any direction of distortion, oblong is stronger to specific direction but the penalty is reduced strength to others.

Not an engineer, stand to be enlightened

if only i had the balls to try it
 

Gentlemen, gentlemen, I really do appreciate all you comments, both positive and those of a more piss taking nature. I am old enough not to be plauged by the impertinance of those still wet behind the ears. Life is so short and must be lived to the full. I allways tell it as it really is. someone asked ," have previous bugs flown". Bug 1 hovered on its first trial (on tethers) Bug 2 was an attempt to utilise composites in the skid bow and body structures. Bug3 was built to encompass lessons learned during manufacture of MK1 and MK2. This machine now currently resides in Portugal and is currently being test hovered by its new owner. Bug4 was untill yesterday undergoing a rigorous ground test proceedure during which i managed to bugger the sprag clutch whilst doing start up proceedures. (sometimes all the calculations are disproved during actual use). Tomorrow, well, lets wait and see. (if we could still work in pounds and feet, and stuff we really understand, then life would be much easer). I mean who the bloody hell invented Newton Meters. Foot lbs. Twelve inches to the Foot. sounds logical to me "to be continued".

I have to agree with Gaseous's post, even a Super Puma or Sikorsky S61 just out of heavies sometimes isn't immediately airworthy. The idea of ground runs then working each control to check reaction is a good one.

Always think what's the worse that could happen and prepare for it at all stages, then when it doesn't happen you can laugh yourself all the way to the pub.

Si

TTB - Nearly every design project is torn between strength and weight, from an engineers viewpoint. In many cases, weight saving is crucial, and round section often provides adequate strength - whereas the strength gain from box section is often badly offset by the weight gain. Cost also comes into the equation, with round section often considerably cheaper.

bugdevheli - I presume the sprag clutch engineering calculations didn't include adequate shock load factor? Nasty stuff, that shock loading. Did you know that a load suspended on a crane hook, if suddenly dropped 2", will almost double the load on the hook/cable/boom/jib? Yes, I must confess, I like the old feet, inches and ft lb stuff. I must be as old as you, I certainly have nearly the same amount of white hair ... :)