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Fanboy
Apr 04, 2005, 12:47 PM
After many years lurking in the forums I thought it was time to register and contribute something myself. :)

Here's a few pics and details of an unconventional hovercraft I built about 6 1/2 years ago:


Striking from a hidden base in South-East England, etc.

One evening, whilst my better-half was out of the country on business, I dug out the old design I'd done for a Snowspeeder flying under ground effect. Realising that you'd need to build it as a true hovercraft (boo), out come the Art of Empire, the old AMT/Ertl plastic kit and the Star Wars Chronicles. Liberal quantities of whisky and orange later and I have a set of roughly 1/10th scale plans and a foamcore shell. Morning after was not pleasant.

I'd like to point out that this speeder was more a proof-of-concept tech demo than a proper prototype. So it's quite crap, as it was built from stuff I had lying around in the house. The RC kit is old Futaba Challenger 35MHz gear (not for ground use), the fan unit is a Morley*, powered by a random 540-size truck motor (timing waaaay out). Servos are standard S418s. The scale was derived from the requirement of fitting the fan within the form at somewhere between the extremes of center of thrust and center of gravity.

The main construction materials are 5mm foamcore, 0.8mm aluminium tube and various sizes of carbon fibre pultrusions and tubing. Liberal quantities of Zap were used to hold it together. The main guns are spring-loaded to reduce crash damage.

The cooling vanes are used for steering - deflection is about 25 deg. from neutral and sufficient to turn the craft on the spot. Fan efflux can be diverted in varying degrees to both drive and lift. The semi-rigid skirt, not shown in the photos, raises the speeder up off the ground by about 15mm, at a neutral AOA.

Operation is noisy and slow, but much more fun than the last man-capable hovercraft I worked on.

I reckon it's possible to tweak this design into a nice little craft. The only really tricky bit is the requirement for an in-scale tapered skirt. Alternatively, the cheap prebuilt toy hovercraft now on the market could provide that component.

I still have all the templates and formers needed to cut and assemble the foamcore shell. If there is any interest I can scan and make available. :D

One day I might even complete this one...


*The fan unit is supposedly one of the prototype Morley ducted fans, given to me by a chap who had a glider which Jim Morley landed a little too aggressively.

RGinCanada
Apr 04, 2005, 01:06 PM
I'd like to point out that this speeder was more a proof-of-concept tech demo than a proper prototype. So it's quite crap

If this is crap, I should be burning 95% of all the stuff I've ever built! Nice job. Any chance you can get some video?

Ray

Umi_Ryuzuki
Apr 04, 2005, 04:02 PM
Welcome to the boards Fanboy,

What a fantastic first post. And you have templates drawn up?
Omg, yes, e-mail them, or post them, this is just one more project I have no time for but have to try... :D

And if nothing else, some of the scale modelers would just love to build so well from junk around the house. I'll send them by and let them have a peek here. ;)

BartMan
Apr 04, 2005, 04:55 PM
I've been staring at these pics for 10 min with my jaw on the floor. Way Cool! Please scan those in and post.

Kmot
Apr 04, 2005, 07:30 PM
That's the coolest looking damn hovercraft I've ever seen! With todays li-po's and brushless I bet you could make it rip!

Welcome!

ropanach
Apr 04, 2005, 08:40 PM
grate job & wellcome.

Fanboy
Apr 05, 2005, 11:50 AM
Many thanks for the kind words. I dug the sketches and templates out of storage and have also remembered a few more details:

1. There was a taped-together proto-prototype made from corrugated cardboard, to check for balance and rigidity. Most of the internal walls and bracing were lost for the foamcore version. Foamcore is great if you don't intend to play outside. :)

2. The craft was very noisy in operation, due to the manky pre-production fan unit and mismatched truck motor. Also, the drive assembly is mounted on a carbon fibre tubing support frame and rigidly bonded to the foamcore shell. Anyone have flat-panel speakers? :D

3. I took a wild guess at the proportion of fan efflux needed for lift, and despite including a servo-driven adjustable baffle plate, was far too cautious.

4. Very high ground loading. I attempted to minimise the skirt and hide it within the profile of the craft. Not easy, as the wing anhedral is greater than it looks.

5. The design is actually 1/12th scale, and dates from September, 1997.

6. The final plenum chamber was a simple box affair and the skirt made from a very slippery plastic sheet (not sure where it came from). Long since gone, I'm afraid.

7. Wildly unstable at speed, due to the very small skirt, which was almost as wide as long. A gyro would be useful in a revised craft.

8. The design was a composite, adapted from many sources. That said, it's the best accurate design I could produce, and is as close to 1/12th scale as possible.


I have found the four A4 pages of sketches, ten A4 pages of technical development and five A3 sheets of scale plans, along with final templates for most of the bits for the foamcore version shown above. Give me a few days and I'll see what I can do.

These pics were taken a few months ago for a friend who wanted to a look. Video? If I make a new skirt assembly I certainly will. We were hoping for enough snow this winter to 'fly' it, but the climate change in recent years seems to have put an end to that. :(

Umi_Ryuzuki
Apr 07, 2005, 12:17 AM
I would imagine that you could attach five A3 sheets of scale plans as Jpgs to one of your posts.

If the resolution isn't high enough then we can look at e-mailing these across the pond.

You have the scale modelers in shock....
Starship Modeler thread... (http://www.starshipmodeler.net/cgi-bin/phpBB2/viewtopic.php?t=25094) :p
Like the rest of us they are confused as to why it is considered "Crap". :D

Tony Oliver
Apr 07, 2005, 04:36 AM
It's English reticence. We have a modesty which does not allow us to blow our trumpet too loudly. Often for good reason, but not in this case!

Superb model.

Fanboy
Apr 19, 2005, 06:20 AM
My apologies for the delay in posting plans. Real life takes priority on occasion, I'm afraid.

I would imagine that you could attach five A3 sheets of scale plans as Jpgs to one of your posts.

Scanning is not an issue. Reworking the different versions so they produce parts that actually mate up is. :)

You have the scale modelers in shock....

I guess this 1/2 size snow Jabba (http://homepages.nildram.co.uk/~nausicaa/Snow%20Jabba.jpg) is for them, then.

I've placed higher-res versions of the images I posted here (http://homepages.nildram.co.uk/~nausicaa/speeder/), with a few additions.

Akura2
May 02, 2005, 09:58 PM
:eek: ...MY GOD!!!! that thing is BANANAS!... that is so cool!

nstaller
May 02, 2005, 11:33 PM
Damn that is awesome.I must have one!!!

Science Guy
Jun 01, 2006, 04:34 PM
Awsome

magicruss
Feb 23, 2007, 01:32 AM
I Want One ! :eek:
any chance youll let go of a set of plans? :D
Russ

DDFletch
Feb 16, 2008, 05:16 PM
I'd love to get a copy of the designs. I've wanted to build one of these things since I was a kid.

toesup
Feb 16, 2008, 08:01 PM
On these 'old' threads, its always worth checking if the designer / original poster is still active on RC Groups.

Fanboy hasnt been on the groups since April 2007.... but it might be worthwhile trying to send an email...