Vertigo experience?

[Nick Reffold]

Hi

Has anybody on RCGroups built and/or flown the Tom Hunt Vertigo design? I just got my plan from MAN and would be grateful for any advice.

Nick

[Keennon]

Nick- I don't know about the flying qualities. The reason I'm writing this note is that my local hobby shop has one of these models hanging up, and is for sale, don't know the price, it looks like pretty decent, I thought about buying it several times. Maybe you could give them a call if interested:
http://www.martyshobbies.com/ This is in California, may not be practical for shipping to UK, but they might have a contact for it's original owner/pilot.
-Matt

[Nick Reffold]

Matt

Please accept my apology for not responding to your kind post as quickly as I should have.

Does anybody have either of the 2 issues of MAN that carried Tom's articles on building and flying the Vertigo. I have the plan pack from MAN but the Xerox copies of the article are too blurred for my weary old eyes. If someone could sell me the magazines or, preferably, scan the pics and post them here I would be very, very grateful.

Nick

[bobandris]

Nick,

What were the 2 issues?

Bob


Matt

Please accept my apology for not responding to your kind post as quickly as I should have.

Does anybody have either of the 2 issues of MAN that carried Tom's articles on building and flying the Vertigo. I have the plan pack from MAN but the Xerox copies of the article are too blurred for my weary old eyes. If someone could sell me the magazines or, preferably, scan the pics and post them here I would be very, very grateful.

Nick

[Nick Reffold]

Hi Bob

They were August and September of 1994.

Nick

[v22chap]

nick ,,,you mean this one???
If so you should be able to blow these up enough to see good ... I have them zipped and can maybe put them on here ,,,never tried that ,but it says zip is a usable file type. There are 11 pages ...

I also just found 6 pages dated Sept.
Larry

[FatBill]

Hi Larry, I don't suppose you could send me a copy of the ZIP file could you?.
I want to see what's involved before I order the plan.

Thanks,

Bill

[v22chap]

When I get home I will do that ...
Send me your email addy as this email deal won't let you send attachments.
mine is : v22chap@hotmail.com

[avianaut]

Nick, I have those Vertigo plans too, I'll get around to it one day. Promise! ;o)

Larry, I'd really appreciate it if you could e-mail that zip file my way too. Would you mind? I'll PM you my e-mail (don't want spammers to get too easy).

Cheers.

[Nick Reffold]

Many thanks v22chap - I have sent you an email.

Nick

[FatBill]

Thank's Larry, I have sent you an email

[v22chap]

All emails answered ,,,I think :rolleyes: :D
Larry

[Nick Reffold]

A public thank you to v22chap Larry!

[avianaut]

I second the motion! A big thanks to Larry. I got it this evening.

So, are any of you planning to build this model anytime soon? My building schedule is too full, I don't expect to make a start for many months, but I do intend to build one.

Cheers.

[ghoti]

When I studied my vertigo plans I got so intimidated by the complexity I just put them on the shelf. I have new set of plans and good copies of both articles (I think) as well but no way to copy or scan them.

If anyone wants the whole package I will sell for 50% off the MAN price.
Send me email if interested to
sturgeon@asis.com
fish

[vtolman]

The vertigo was a time consuming project to do without help, as it was hard to find anyone experienced with it -- even 12 years after its concept I only know of 3 people who have got it to work correctly.

Finally I got the right advice to perfect its setup, and went on to make over 40 inbound and outbound transitions with it.
Plus the odd crashes.

The last crash ---- never to be rebuilt by me---- knife edged in from 12 ft up on takeoff, caused by stupid me doing a way to low outbound transition and (stirred the pot) played with roll / aileron and yanking up elevaor in transition. (roll acts as yaw in trans)

It once fell from about 20 ft up in hover as it was nosed down into the wind with low fuel it sucked air from the back of the tank and flamed out.

I have sound advice on it if anyone is up to the challenge.

It was very rewarding to master its hover and transitions.
Kingsley

[avianaut]

Kingsley, can I take a raincheck on your generous offer? When I get around to building and flying one I'm sure some qualified advice would be most welcome. I'm up to my a$$ in aligators right now.

Cheers.

[Nick Reffold]

Kingsley,

I notice from the pics that your Vertigo tailplane is lower than in Tom's plan. I would be interested to know why.

Also, what covering did you use?

Cheers

Nick

[vtolman]

Nick THE TAIL PLANE THEORY was to keep it high out of the way of the prop thrust when it transitioned to avoid it effecting the pitch as the air flow hitting the lower tail surface and causing pitch up outbound.
Mine did not seem to be greatly effected by this, (as it transitions quickly past he horizontal stabilizer anyway --- besides it is more complicated to build a high stab.) however I never made a high tail horiz. stab. to know if it was any better or not --- it transitioned with similar qualities according to Jaffray Stevensen who had the high tail set up.
The picture of the electronics with R P Y is misleading as it needed 3 gyros but 2 are for pitch and 1 is for roll as there are 2 pitch hover vanes split which are mixed and perform yaw as also.
Old technology as now I would use an external mixer I think ??
I'm on the juice tonight :rolleyes: I may backfip on that then I am clearer
Kingsley Kronk

[avianaut]

Kingsley,

When your bird had it's mishaps, what broke? Is there anything in the airframe that needs revision, strengthening etc.? Do you think anything could be built lighter without compromise?

I would like to build as light as possible. (Don't we all?! ;o))

Cheers.

[vtolman]

You can see from the photo I had the fuselage center wing strengthened with 200 gram - 6 oz carbon fiber and it only broke where it had no carbon in the center as I could not get to it.

It was constantly getting fatigue cracks in the fiberglass at the 10 and 2 o'clock areas of the U fuse, even from bumpy landings.
This U piece is way too fragile, and makes it hard to rebuild when it breaks in half, as happened once when it ran out of fuel and pancaked.

Hence the carbon rebuild was done and did save it cracking again there after.
I would carbon most of the U shaped piece on top and bottom (edges not needed) as my picture, and further to that extend it shaped like a Y piece carboned to add strenght to the nose piece of fuselage.

Don't make that silly plywood nose fuselage design as the plans, do your own 3/8 bottom and 1/4 sided balsa box (simple, light and stronger and easier to repair, add or modify) and carbon it to the U as mentioned forming a Y.
In other words design it to where you want it to break, so the nacelle and Y fuse stay together with most of the electronics intact.

Designing another VTOL project last year, similar to the vertigo, I purchased 7/8 " carbon fiber tubes to be used for dual fuse booms like a heli, and carbon fiber cloth to make the Y fuse complete with retracts for a 7 foot span model with foam / balsa wings to run a saito 180 or OS160 with a 18x5 open prop design (no nacelle) HUGE thrust !
I made the center engine mount (as photo) which was a tilting center wing, come engine mount, come servo mount, come control vane strut mounts.
BIG project finally abandoned, and I sold most parts. :(
I have got to stop raving on. :eek:

[avianaut]

Kingsley,

Thanks for the tips. After looking over the plans I was concerned about the structural srength of that 'U' section myself, but hadn't come up with a solution I was happy with. I wonder if a large diameter thin walled aluminium tube (round or even square) bent in a 'U' shape and embedded in the centre wing section might do it?

The nose electronics area should be easy enough to redesign, I'll take your advice on that.

Some more questions, I hope you don't mind.

Do you think the landing gear is suitable? Is it too stiff, maybe needs a bit of spring action? What about tricycle gear instead?

Does it need specific types of gyros to fly well? Would GWS PG-03 or similar be workable?

Thanks for the pics too, very usefull.

Cheers.

[vtolman]

Avianaut

The carbon fiber is the way to go if you are comfortable using it, slap it on top and bottom your done. Tricky slippery stuff.

Landing gear is a compromise - its got to stay light, so springs and wire are too heavy due to the long length they need to be.
I used carbon arrow shafts and glued 1/4" dowel inside as the plans and kept spares ready for the inevitable breakage.
All I might suggest is somehow rubber mounting them at the bottom of the fuselage so they don’t snap as easy, so they give when you have a slight sideways or harder landing. Bob Brown did the trike as in the photo.

I tested the cheap GWS PG-03 and HITEC GY-130 and they mostly do not make the servo travel enough, and they return the servo too quick - the tilting of the fuselage is not as quick as a heli tail response - and they don’t re-center accurate enough.
I know the CSM 560 or mini SL560 WILL work, and possibly the CSM 450.
People have tried the FUTABA GYRO 401 and it does NOT work.
It is as if it requires a partial heading hold feature and the output be amplified to give lots of servo travel.
My vertigo control vanes would move beyond the 45-deg travel and slightly hold there for a split second longer then most standard gyros - at the slightest pitch movement induced on the model.
I use old Arcamax gyros which had this special quality, but are no longer made, as they were cheap to buy on ebay, but are now hard to find.
Have you read any of my gyro testing recommendations in these forums.
To be honest I still dont know what the real gyro answer is, it may one day be solved with mini accelerometers or whatever.

Kingsley

[avianaut]

Thanks Kingsley,

My LHS now stocks carbon fabric and veil, so that's possible.

What I meant by "tricycle" was two mains and a nose wheel. I notice Bob Brown's bird has a tailwheel under the centre fin, and no nose gear. That's a nice looking machine, by the way. A plane like this just looks odd to me as a tail dragger. I was thinking maybe a short coiled wire at the bottom of the mains to reduce landing shocks a little. I understand that weight is an issue.

Correct me if I'm wrong, but Arcamax gyros use a spinning wheel sensor, don't they? Virtually all the current crop of gyros use a solid state angular rate sensor, they are not really 'gyros' at all! I, too, have tested Futaba, JR, CSM and GWS gyros for other uses and I agree that they are not good. Great for helis, but it looks like the difference is critical for this application.

There is attitude sensing and control packages out there, but too many $$$$ for hobby use.

Thanks again, Kingsley.

Cheers.

[vtolman]

Aviant
Try what you think will work.

I only decided against the tricycle as I had already made that week nose fuselage set up as the plans, and didn't want to rebuild the Y design as discussed.

I had two active rudders with moving tail wheels and it was still impossible to tight turn when taxiing, so thats why Bob went to the one tail and wheel.

I even thought of using 2 @ 7/8" carbon tubes for booms V joined down at a conventional tail set up at one stage.

Why taxi when you can hover I hear people thinking ?? - Because at 17000 rpm it is incredibly loud in hover about 95 -100 dB and only ??? 1/4 the dB when taxiing near the pits etc.

I once got told to leave by the safety officer at another flying club I was visiting.
He had his dB meter out showing me like a policeman with his radar.
It was all worth it with over 20 keen onlookers asking for more demos.

Hence I always taxied to the far end of the runway prior to BLAST OFF.

I sure miss flying it.

Check this link out http://www.rcgroups.com/links/index.php?id=4453

[avianaut]

Kingsley,

Looks like the gear needs a little more thought, you mentioned some things I hadn't thought of.

Where I fly there is no club, no safety officer, no runway. And no-one cares! Noise won't be an issue, although by the time I get around to it, electric may be a viable alternative. Do you know if anyone has tried it with elec. power?

Cheers.

[vtolman]

avianaut

I wanted to build an electric Vertigo but the math don't add up because of all its servos, and tilt motor setup, and nacelle etc all adds drag and weight that electric power can not do well enough at this time.
Hence I built the Twin Electric VTOL - twice the prop area, half the weight, 4 less servos, one less gyro, easy to build and repair, smaller electric motors / LiPo's are much cheaper also.

Kingsley

[avianaut]

Kingsley,

True enough, but by the time I get to it that may have changed. LiPo batteries are steadily getting cheaper and discharge rates are on the up 'n up. Comparing the cost of an OS .46 DF engine and an elec. motor/ESC I think the motor is cheaper already. The effect on AUW? More research needed. I currently fly nothing bigger than 400 size elec. All my bigger stuff is still glow.

Your twin VTOL is very clever. Well done!

Cheers.

[Terry S]

An electric version may be possable with the use of lots of white foam. Maybe a large prop instead of a ducted fan too. It would be good to see.

Terry

[v22chap]

The vertigo already uses a ducted "airplane prop" ,,not a ducted fan.So that idea is out as it would have to be a micro helicopter blade unit to get one big enough to lift the foam I am thinking. :eek:
Larry

[Terry S]

OK Larry I missed that fact. It must need the same sort of set up as you guys are using for your twin prop/rotor VTOLs but one big prop instead of two smaller props. The thing that worries me is what angle can you tilt the aircraft to while hovering before it falls from the sky ?

Terry

[avianaut]

Guys,

I understand that Tom Hunt did some research on the duct and props, and basically came away with the feeling that a prop in a duct was better than an open prop, or a smaller duct with a fan, at least in static thrust. So that's what he used.

I see no reason not to change, so long as static thrust is somewhat more than all up weight and it offers good performance in forward flight. I say that because, for example, a heli rotor gives plenty static thrust but has little hope in forward flight, and a bell mouth duct may give more static thrust but will have high drag at speed.

There are elec. motors that can easily match the .46 glow engines, probably a geared brushless in-runner with suitable ESC and batt., but the issue here is what will it weigh compared to a glow set-up, and will the cost be acceptable all else considered. I don't have the answers right now.

Cheers.

[v22chap]

Yep ,Tom did that comparison and you are right <,I don't know either what an electric motor and battery would weigh as opposed to the IC motor.
Here is the article on the Fan prop comparison.

Terry I would think that all you need to do is sub the IC motor with the right size electric and the fuel tanks for battery's and you would be all set . Just not sure how the weigh is going to come out as I think most electrics are a little heavier than IC motors and it is marginal on lift now.I would do a lot of motor research before I would try it .
Good luck and keep us posted on what you find.

[Terry S]

The figures dont look that good. I think it would work but going back into the hover for landing would be iffy !

Terry

[avianaut]

Terry, too true! On glow powered models the thrust to weight improves at the end, E-power the opposite. Noted, thanks.

Cheers.

[v22chap]

Luke ,,, I have been trying to send you the mag articles and it keeps coming back undeliverable ??? Could you pm me your email address or maybe another one that might work.
Larry

[FHHOBBIES]

I wanted to get these plans for a long time and use it to build a small electric Depron "park size" version, I'm sure I could also simplify it as well. If only I had the plans!