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ashleyhoverscout - n/a
16-Feb-07, 07:48 PM
I need to fit a remote 'cut-out' device to my hovercrafts, so that I can use them for our Scout Troop, and be covered under the Scout insurance. I believe that you lads who use craft for corporate days have a similar device fitted.

Can anyone pass any info across? on how /what and where to to source items to build one.

The only professional type i've seen are for jet skis, and are way out of our price league.

Considering we use a 241 acre, RAF helicopter training ground to use our craft, we still have to have these remotes fitted. Still it's only taken two years to get this far with Scout insurance, as they originaly wanted to class hovercrafts with flying a cessna light aircraft!!

Any help appriciated

Peter

jon_curtis - n/a
16-Feb-07, 08:41 PM
http://www.avdw32.dsl.pipex.com/electrical_accessories.htm



9 quid. have bought the same thing in chandlers for just over a fiver!

Vortex - n/a
16-Feb-07, 09:04 PM
When you say remote...do you mean wireless operation so you can stand at the edge of a field and turn the hovercraft off???



If so give me a call 0779 3807073



250m range about 125



Keith

Ian Brooks - n/a
17-Feb-07, 09:51 AM
How about a 2 channel radio control (about 45 from the model shop) and connect the servo to a standard kill switch lanyard?



Ian

Nick Long - n/a
17-Feb-07, 01:33 PM
It sounds like the requirement is for a emergency stop system, and so unfortunately a normal remote control is not suitable without modification.



You need to consider the situation if the craft is out of range, or there is interference, etc, at the moment you want to stop it. Therefore you need a "dead man's handle" type of system, that relies on getting a continuous "enable" signal rather than an occasional "stop" signal. I guess that's what the system the Boss is referring to does.



The original posters reference to light aircraft is interesting. I have been involved in several events that involved taking Scouts up in aircraft and there was no problem with absurd regulations.



Nick

srn4 - n/a
17-Feb-07, 03:53 PM
You could use a cheap radio system as Ian suggests...



Just buy a plug in failsafe unit with your servo...



Basically means that if there is a radio failure, low battery, interfereance or out of range issue the failsafe automatically moves the servo to the "failsafe" position which in your case would be OFF/engine kill...



They are about 13...





Going one step firther, if you take appart an RC servo you can use the internal motorfeed wires to switch transistors/relays so you would then have no mechanical device to fail, it would simply be an electronic relay that would shut off the engine when the radio signal tells it to...



IMHO Its simple and super reliable!



Make sure you buy a 35Mhz radio system designed for RC aircraft as it is far less likley to get interfeance...



(im guessing a rough cost for a complete setup using the relay setup as mentioned above would cost no more than 45 all in!

Keith Oakley - n/a
18-Feb-07, 10:28 AM
I'd look hard at the reliability of anything you fitted. A false shutoff could generate more problems than it cures, for example whilst the craft is travelling sideways at speed causing a rollover, and with the driver unbraced for the impact. My experience with ELS is there is considerable radio interference from some craft. eg on the Cybiko PDAs I wanted to use the range reduced from 250m to under 50m when craft were started up, rendering them useless.

team black - n/a
18-Feb-07, 11:46 AM
The Boss and I spent some time working on the spec for a system, and sourcing the eqpt. I'd give it serious thought.



Keith(O) rightly points out that a sudden stop could cause more problems than the one you're trying to avoid.



Cheap R/c systems tend not to have the range or duration that you are likly to want.

hovmart - n/a
18-Feb-07, 01:39 PM
we used a go-kart system that reduced the revs to a prerestricted speed, and allowed up to 1o karts to be monetered, all this ment if you hit the panic button it slowed them down so you can red flag them back to the pits for there Bo...... not sure of the make but it was made for gokarts and worked fine on the 3 craft we were using