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chrismdaly - n/a
16-Oct-06, 08:11 PM
The Hinckley Air Cadets have got hold of an old hovercraft as a project to race in juniors next season. The former racing number was 178 and I believe it was aquired from Southam Air Cadets. The hull looks a bit like a small Moto Cyclone. Does anyone know its history and what engine it had.



Thanks.

Del Smart - n/a
16-Oct-06, 08:41 PM
Hi Chris



Is it a blue hull with a rounded front ?

Can you post a pic ?



Del

Cpl. Bee - n/a
16-Oct-06, 09:29 PM
Hi all,



Peter Bee here, I am the NCO on the squadron in charge of the website and the NCO in charge of the hovercraft Project (under Chris). As such I will be doing a web blog on the progress of the build, the training and the racing season at:



http://www.myspace.com/198squadron (www.myspace.com/198squadron)



I will endevour to get pics of it in it's current condition ASAP

chrismdaly - n/a
17-Oct-06, 06:18 AM
Hi Del,



The hull is almost rectangular and has no evidence of a central steering mounting; it could have been a cable or rod arrangement on the right hand side. The fan frame and a strange set of blades (they are plastic) are still with the craft). The duct looks about 800mm in diameter and there are no flow straighteners except for one central board that has the rudder attached.

Cpl. Bee - n/a
17-Oct-06, 09:12 PM
Chris,



Ive just been in contact with one of the local field owners. He runs a couple of Microlights off a grass strip quite close to me (about 2-3 minutes walk). I contacted him about old microlight engines that he doesnt use anymore and he has told me he's meeting a few guys that have given up because of various reasons and he says he will get some estimates for their engines.



Pete (Bee)

jon_curtis - n/a
17-Oct-06, 09:49 PM
yeh you can pickup rotax engines, and props for less than a couple hundred quid. nice

Cpl. Bee - n/a
17-Oct-06, 11:08 PM
yeah - just depends what price he'll negotiate for us and whether (if it comes with a prop) whether it'll be a suitable prop for the duct we have or whether we'll be using the ones we have with the hull (or obviously modifying the prop that comes with it)



Either way this guy will try and see what he can do for us

chrismdaly - n/a
18-Oct-06, 06:06 AM
I believe the CO has another fan in his garage. We need to create or aquire a template to make the skirts.

Can you photograph the hull and publish it so that we can get a definitive identification of the model type.

Cpl. Bee - n/a
18-Oct-06, 02:03 PM
Yeah - i'm going to haul my ancient Digi-cam out of it's bag and get some photos of it and all the componants.



If I take a tape measure down i'll measure up the duct and fan blades and crack on with counting teeth as well

Cpl. Bee - n/a
18-Oct-06, 10:56 PM
Ok, Here's some images



http://img.photobucket.com/albums/v224/SoldierOfTerra/Hovercrafting/DCP00980.jpg



http://img.photobucket.com/albums/v224/SoldierOfTerra/Hovercrafting/DCP00978.jpg



http://img.photobucket.com/albums/v224/SoldierOfTerra/Hovercrafting/DCP00979.jpg



that better for you?



Oh and Chris, been on the belt/pulley calculator



It needs to know what belt type we'll use (H-type or HTD) and I can only enter the number of teeth on the engine, the number of teeth on the fan and the engine speed and it'll give the gearing ratio, the fan speed, the belt speed and the PCDs.

Jamie Lewendon - n/a
19-Oct-06, 11:43 AM
It is definatly a moto, and judging by the fact it has green blades, it is an old moto. The first thing you want to do is take the blades out, and put thm in the bin. The Green blades are very old, and inferior in strength to the newer white blades. Don't worry about the belt yet, you need to decide what engine you will be using, as this will affect the ratio, fan rotation, and belt length. The fan has to be correctly matched to the engine for it to work efficiently and effectively.



Jamie

Cpl. Bee - n/a
19-Oct-06, 12:09 PM
Jamie here's the details I was working off:



Powerplant: Rotax 447

d on the prop: 8"

teeth on the prop: 50

RPM(Engine) in operation: 6800



and we are hoping to use as many of the original parts as possible in order to minimise the costs to the squadron. If we get any props with the engines we have found then we may well use those.



Peter Bee

chrismdaly - n/a
19-Oct-06, 03:50 PM
It has a 750mm duct with a multiwing 9 hub. Will 4z's be okay?

jon_curtis - n/a
19-Oct-06, 07:57 PM
if i was you, now you have the chance i would put on a bigger duct!



750 fan will have to spin quite fast, will be noisey and will have poor acceleration compared to a 925 duct for example

however you might decide to put on bigger!

conrad will do spares for the moto, so you can get bits of glass that are very past it, or ducts



looks like it maybe had a bike engine in the past, i would salvage what you can mechanically (bearings, pulleys etc etc )and bin that frame, the duct an all the blades etc as jamie said. you have a lot of work there, so a little more to build an over all better craft in the future will be worth it in my mind.

Iceman - n/a
19-Oct-06, 09:53 PM
...in other words, sc**p everything and start from scratch??!!



The basic setup there is fine as a starting point, the frame can easilly be modified to accept a Roatx or Robin engine and the 750mm duct is reasonable for a junior craft. We run 750mm ducts on our corporate craft and they are perfectly acceptable.



The Moto is a very good hull and with a nice engine in the back, they will have a very useable and driver friendly craft, ideal for air cadets.

Cpl. Bee - n/a
19-Oct-06, 09:54 PM
Now the question is



Do you think the craft would be able to handle FJ and FN on its first year out after the re-build?

Don83000 - n/a
19-Oct-06, 11:05 PM
Go take a look at this it's a very old rebuilt moto with a Fuji Robin engine and 750 duct carrying a fair bit of weight.

http://video.google.com/videoplay?docid=-3257260580220236106 (http://video.google.com/videoplay?docid=-3257260580220236106&q=hovercraft) &q=hovercraft

chrismdaly - n/a
20-Oct-06, 05:57 AM
The objective of the project is for the Air Cadets to produce and maintain a useable hovercraft. We could have all made modifications to the Bearwood Tank but at the end of the day it has probably had more use than most craft.

The suggestions are all usefull for the cadets. You have all had far more experience than them. Please keep them coming.