Hey one track,

I have in my pocket 2 Florins, and 1 half crown, not many folk remember those, or know what value they are today!

Peter R-B:ok:
Vfr

vfrpilotPB/2 - Ahhh, yes - florins and half crowns - but can you remember buying threepenny ice cream cones?? :D :)

Entertaining thread, well done one and all. The spouting off by people who clearly don't know Bugdevheli, or "Julian" or the abilities of either is really amusing to the few on here that know both of them.

Go for it, Bugdevheli.

Andrew, a friend from years ago, from when the Mini 500 still showed promise.

all i need now is the balls to try it
 

Andrew. Thank you. Its been a few years since we met. J is alive and well and married (just in case you did not know). He and she are both qualified and have their own aircraft Regards you know who.

Hey Andrew, It was me that mentioned Julian and there was no criticism implied. If its the same person, he's smart. He was developing a remote controlled tracking device to adjust the pitch links in flight and he once tracked my Enstrom with a chadwick. I only knew him through John Dunn and when John died I didn't see Julian again. His homebuilt flew brilliantly. People like him and Ben are to be applauded. :D:ok:

Bug - outstanding! It's people like you that put the "Great" in Britain! I would love to see it in a low (safe!) hover. The very Best of British to you.

Gaseous, I didn't think that you were being critical, I am just amused that people just...... Well you know what I mean.

Bugdevheli, I didn't know that J and Y had got hitched. I actually tried to visit him recently (3rd Sun in November) as I was in his neck of the woods. He had gone to see you for the weekend! I am up to date on his flying activities and their Wittman Tailwind. My heli licence is a bit lapsed now but I am still flying often. I have gone all "plank", I have two 3 axis microlights, one which I built from a kit, and we have just ordered another kit from the Ukraine. Must sell at least one aircraft to pay for the next one.

keep me posted, Andrew.

onetrack - understood re dilemma of balance 'twixt strength and weight of tube vs. box section - makes sense. As for threepenny ice cream cones, yes - i remember them rather too well, along with tanners and coppers :sad:

I also clearly remember making my very first purchase - a Mars bar, c. 1963 and costing the princely sum of 3d... Ah, those were the days, etc...

Bug - we're all dying to know what the next step in the plan is - if there is one :)

TTB

Has anyone tryed using a felxible drive for the rail rotors yet?

I have seen it many times on RC helicopters and never heard of any failures

A larger variant will make for a system with many less parts with high tail gearbox setups

Run the shaft through a bent sleve lined with nylon. As long as its correctly lubricated, I dont see why its not a good idea

Any thoughts?

Simon :ok:

My first purchase was for a tanner.

I gave the lady a bob and she offered a pair of threepeny bits in exchange.

T_D

Who bonded the blades?
 

OK I'll ask my obvious questions based on my usual themes: Are the blades bonded? If so by whom? Using what adhesive? After what surface preparation process? How were the bonds cured?

Same questions for the composite structure joints.

If the answers involve ACME and Wylie Cayote I'm outa here!

Regards

blakmax

Perhaps this product might offer the soution?

Bulls Balls®, Big Boy Nutz™, Original Truck Balls™, Truck Nuts, Truck Nutz, Bike Nutz & Bumper Nuts.

Not sure of the weight penalty!:eek:

bugdevheli - Don't worry about risking your neck any more - I found the guy who'll volunteer for the TP job. He's the right size for your cute little machine, and suitably outfitted in the cojones dept, as well ...... :)

http://i48.tinypic.com/11qhf6r.jpg

all i need now is the balls to try it
 

Onetrack, he is obviously a squirrel pilot. I have it on good authority that they are all endowed in a similar manner. Toptobottom. When i have proven the Bug airframe and drive systems, i plan to construct a full size ring rotor a mockup of which can be seen on one of the pics posted (the mock up sits on top os a pair of blades) The ring rotor is device that permits enormous inertia without the weight penalty of heavy blades. My belief is that until these VLH machines have loads of inertia they are risky at best, and deadly in low level operation, particularly the sort of flying carried out by low time pilots.BUG.

IMHO, there's a lot of cock talked about "aircraft quality", especially when it comes to GA and LAA /experimentals.

Often it comes down purely to the traceability (paper-trail)

Those "automotive quality" drive-belts (flat, multi-vee) are extremely durable,"fit and forget" items.
The longer, "serpentine" ones follow a convoluted path,sometimes with more than a 180* wrap round pulleys of~8-10cm diameter, driving water-pump, aircon-pump, power-steering pump,alternator and cooling-fan....all fluctuating loads at fluctuating speeds in an engine going ~900rpm to~ 7000 rpm. life-expectancy is often 100,000 miles +without failure or maintenance.

that tail -drive with balanced-loading on both sides of the boom (limited float needed to even-out inequalities between pairs) seems a simple, elegant,low-stress,low-maintenance tail-drive solution,

Model Helis using a similar toothed-belt to that employed in computer printers, are extremely reliable and the Raptor series,using that drive has been the most popular mass-produced kit for a fair while.

Glad to see someone with the courage of his own convictions not letting the nanny state suffocate him.

the jobsworths would not have allowed the Wrights to fly, nor the first hang-gliders.

Aviation at this level sems to have thrived on innovation outflanking the beaurocrats with their control and legislation.

Bravo!

All i need now is the balls to try it !!!
 

Well all i can say is , if you have had the Balls along with the commitment and passion to build, design and engineer it then im sure you have the balls to fly it!!!
How wonderful that there is still someone out there with a true passion for design,engineering and flight, if it were not for people like you we would never have had the light bulb! the first tv! or indeed the first form of flight !!!!!!!
well done and keep up the good work anyone who cannot see the time and effort gone in to this machine and the commitment from yourself to it is obviously stupid.:D

Sorry, been busy on other stuff...
 

Bug,

A lot of carefull thought has gone into this machine. I'm guessing that you've done some testing on those skids to make sure they absorb energy for various scenarios. That rotorhead / swashplate looks like an engineering story in itself - one i'd be interested in hearing. Do you have any closeups of main rotor, tail rotor, control mech and rest of machine? Unless you are worried about disclosure of design etc. Looks like some interesting drivetrain around the (Triumph?) engine. Are those more belts hidden between those two aluminium plates?

The thing that astonishes me is that this was all designed by one person! Looks like many man-years of work. All you?

Just remember that every new engineering project is a collection of faults just waiting to be discovered. Take every opportunity to check that fatigue is not gently accumulating cycles (i know you've done FEA) and that wear is not gently rubbing away contact. Check every bolt torque as often as you can (vibration & joint movement) and look to see that those belts haven't picked up any FOD. Definately check welds very regularly - with die penetrant if practical.

BTW does the rotor / drivetrain have enough inertia without the ring-rotor for <2 seconds of flight with no power? Talking with the many (always extremely helpful) test pilots on Rotorheads i get the impression that the key is to carefully think out what the objective of the each flight is then figure out the absolute minimum risk way to achieve that objective. Sometimes that may involve sitting down for a cup of coffee.

Just my £0.005...

This would work with a lightweight Turbine, in place of the Piston job! one of the Prune Rotorheads quite possibly has just the thing plus the knowledge! :ooh:

Peter R-B
Vfr

all i need now is the balls to try it
 

Graviman and peter RB. Just a clarification! One of the photos posted shows the mk 3 machine which has a ring rotor device mounted above its normal pair of blades. This was done just to expose the ring rotor concept to interested parties at an airshow. The actual ring rotor will be fifteen feet diameter. The Ringrotor is something i have been working on, to provide great inertia with a minimum weight penalty. The Mk4 has been designed so as to be able to retro fit the ring rotor when airframe and drive systems are proven.This is why the tailboom lenght is adjustable. The current engine is a Yamaha FZR. I will post some closeups of bits you mention. Thanks Bug.

Ah, it's a Yamaha FZR. Which size? I'm guessing you went with a 1000 but run it derated - not sure how many thousand miles of motorway speeds/power motorbike engines are designed to last these days. Helis seem to aim for a few thousand hours at least.

I like the concept: figure out the single main obstacle to making helicopters safe, rotor inertia, and then design a rotor specifically to improve this feature. And as a side benefit improve the aerodynamic efficiency by a potential maximum of 30% for a given rotor diameter. This one deserves to succeed!

Normally rotors are tested on top of whirl towers. Why not firmly bolt the whole helicopter to a balance, maybe out of ground effect, then "fly" it to check the performance? Or strap it to a weighted trolley (heavier version of your castored wheels on the skids) to keep it on terra-firma while you pull collective to what would be hover for a series of ground runs to get the feel of it? If you are sure where the C of G is then you could mount heli to trolley with four ball joint end links converging just above CG (for stability)*. Best if ball ends attatched to the fuselage, as close to C of G as possible. Use a scissor link (or drive shaft with sliding splines) to make trolley follow in yaw.

This would give you the feel of the machine in flight but without putting yourself at risk. In particular, confidence that the machine is behaving itself dynamically, including tail rotor and main rotor in flap-back. If you check all of the bolts, welds, belts, etc after each run you will prove to yourself that the machine is reliable.

Just a thought.


*I originally suggested tethers, but these would cause problems as they became taught. Also they do not allow various collective settings to be tried.