MalcolmL

New to this - what's the deal on hovercraft ? Don't see much about them yet they seem to be interesting. MalcolmL

hpiguy

I own the hovercraft on this link:

http://www.quicktechhobby.com/spotli...Hovercraft.htm

Mine is the SK-5 model. I painted mine in Army colors and used the supplied
decals. I love it!!!!!!!!

It is very simple to build, huge (the dimensions don't do it justice until
you actually see it in person), and fast. The kit includes everything
you'll need except for a radio, battery, ESC with reverse and one standard
servo. It even includes LED running lights and all the wiring harnesses and
splices and switches!

You can use the cheapest reversing ESC ( I used the Traxxas XL-1) and it
will work fine. It has to have reverse as reverse on the propulsion motor is
your only brake. It's only running the propulsion motor and it's a 540
Mabuchi with a pusher prop. I would not recommend faster motors for
propulsion until you get VERY good at "flying" it. The propulsion is so
efficient that even sealed inside the hovercraft the ESC never gets hot even
after six or seven packs in a row.

The lift motor has a switch that is either on or off to provide constant
lift should the propulsion motor or electrics give out over water.
But it does come with floatation foam in case it does have a close encounter
with a big wave.

Mine easily hits the 30mph listed as nominal speed, so it's not a lie. On
hard pack snow or ice I can wind her up to an easy 40mph. For water or
other mildly (cannot be run on tall grass or surfaces that could cause
aloss of air under the seal bag i.e. sand, loose deep snow, gravel, rocks,
rough water) uneven surfaces you can adjust bag pressure by closing and
opening the air intake on the lift motor. I get about 8 minutes run time
off a 2400 NI-CD pack.

So you can have a high performance hovercraft with easily replaceable spares
for only about $250 if you have no electric stuff at all.

I swapped the ESC, and radio from my boat and a 9 dollar Tower Hobbies servo
(faster and stronger servos will not make any difference in how it handles)
so this project cost me about 180 bucks. And anyone with an R/C car could
do the same.

I plan on taking some pics of it in the snow soon and I'll try to remember
to post them.

MalcolmL

I had completely given up on this one but thanks for your interesting response. Have you any experience of ic engine powered hovercraft ? I like the idea of lots of noise as well - as with the full size ! MalcolmL

hpiguy

I personally do not have any experience with gas hovercrafts.

But the one I own has the parts and accessories for running a nitro engine included with it.

The instructions tell you how to run a gas engine on it. So you can use gas engines with this one and I assume it will be even faster than my electric version.

jamesr-RCU

try the folowing links
http//groups.yahoo.com/group/rchovercaft
a UK site for r/c hovercraft bods with freeplans! also
htp//www.hover,globalinternet.co.uk U K Hovercaft Museum , well we did invent them
have built 2 hovercraft one 'Finger Trouble' electric about 24 x 15 which as successful plan availbale from Traplet and at present just finishing 1/24 scale model of HM218 sidewall hovercraft Port of Rotterdam fire and rescue ?boat
If anyone interested I have photos.

Propellerhead32

Hello all,
I am still constructing my own hovercraft (see attached image), but there are still a few problems to solve.
Currently its powered by an ENYA 60-4C engine which seems to be lacking some thrust. The engine is mounted backwards with a reverse propeller. Behind the engine I plan to install a venetian blind like device to generate reverse thrust out of the "ears".

As I am in a hovercraft racing club and my buddies asked me to hold up the modeling section for a feature on german TV (where that picture is clipped from) I completed it the quick and dirty way. As you can see, the bow is coming high out of the water and there was no airflow at the underside of the skirt.
Later it turned out that the skirt detached from the underside because of the rough surface (its a sandwich design and the underside is just glass/epoxy on a styrofoam layer) and the water that got sprayed on it.

As the prototype (made of a styrofoam board) worked fine I expect to be able to sort out the remaining problems.

Any comments will be appreciated
Tom

Hairball

Here is some eye candy for you guys. This is what a creative hovercraft-thinking mind can come up with.







No, its not mine. Wish it was though.

The trust fans are varible pitch fans (think helicopter) so you can can't the direction of the trust on-the-fly. Its a twin .40 engine powered machine, and its supposed to go very very fast.

It was a mechanical engineer student's project.

rcboatscars

Hey
I am currently working on a 40 sized hovercraft kit from australia. it looks very cool, has fiberglass one piece body, skirt with blow up innertube concealed for lift help, have seen short video of it and it looked great, am having a challenge getting the engine - carb - muffler - prop all alligned properly, but it is getting close to completion. has been a very tedious job, but the results i think will be well worth it. to see the video, use your search engine to look for hovercraft model australia and think you will find it. JB

Big Ted

Hey rcboatscars, what brand is that hovercraft kit you got from australia?

Yogi-Bear

http://www.model-hovercraft.com/ go to this iste and they have a small scale model with a 540 type motor as lift and propulison motors it looks really good checnk it out its called the Griffon 2000TDX
1/10 Scale model

the completed models look really flash if anything its a good start im sure u can adjust the design to suit ur needs

jamesr-RCU

Australian site is


www.remote-control-hovecraft.com

Price $199 for ARTF kit less engine and radio

plus I assume postage at 5.8 kg weight

Looks very impresive ad probally noisy

rcboatscars

Big Ted
The kit i have is called an ALL LANDER REMOTE CONTROL TURBO HOVERCRAFT. the video is great, but the building instructions are terrible, and the illustrations photocopied, and they are even worse. i originally bought an os 46 LA to put in it. it wouldnt fit worth a flip, so i had to order a MVVS 40 (the recommended motor for it). great. only the exhaust muffler included with the kit wouldnt fit without major work on the fiberglass body, so i paid $40 to have the muffler cut down to fit in the thing. I am still working on getting the engine lined up to fit with pre-drilled mounting holes. the performance of the finished model better be super......or all these headaches were for nothing.....

Big Ted

I'm getting more and more interseted in these hovercrafts. I was going to make my next project an airboat, but I think this has taken the lead!

Just another few questions.

How does the model get it's lift from the one engine?
what is the skirting made of?
and lastly, is the propulsion fan direct on the engine? or is it belt driven.

I think if I can get enough ideas i might try and design and built from scratch. I've got a .45 aero engine for thrust and a .15 car engine I might be able to use for lift.

I'll keep progress posted anyway
Cheers Ted

rcboatscars

Ted
The engine is direct drive, no belts. the skirt is made of a ripstop nylon (tough) material, and the floor area behind the prop has an opening for some of the air from the motor to go to blow up the skirt. on my model, there is also an inner tube that goes around the underside of the craft, inside the skirt, that has an inner tube air valve that you actually pump up so that there is always positive flotation available. think of the skirt as a half round object connected to the outside of the deck, and to a place 3 inches in from that on the bottom of the craft. the engine blows it up, and the relief holes on the inside of the skirt dump excess air toward the inside void under the craft. this air then escapes out from under the blown up skirt, thus creating an air "cushion" for the vehicle to ride on. you can see that having a hard surface to run on is pretty important.. they dont do well on grass. i think one engine will do the trick, but if you insist on two, probably an 049 will blow plenty of air for the skirt. the lighter the better. JB

Big Ted

Hey thanks a heap for the help! A bit of reaserch, and i'll be onto the plans. An .049 with throttle control would be good so i can adjust the hover height.

Also, providing there is fuel pressure, etc. Can a nirto engine run in any orientaion? I'd consider putting the .45 in upside down to lower the cg.

Hairball

You can't really adjust the hover height. You can increase the pressure under the craft, and that will raise the height a little bit, but it you get more than an inch or two off the ground, the craft will "roll" off the cushion of air, hit the ground, and then air up again.

Not a problem on ground, but could be a major problem on water. The best setup would be for it to be off the ground just enough to where it isn't touching, so its just gliding on air.

rcboatscars

Ted
my experience says that a nitro engine can run in just about any position, and running one upside down to lower the cg is a good idea for a hovercraft. i agree with our friend from japan, you cant really adjust the hover height, you just need enough air to create a little clearance between the skirt and ground . i wouldnt throttle an 049. just use the needle to fatten it up or lean it out to get the rpms you need. you may have to play with the cuts on the inside of the skirt to get the right amount of air escaping to create the small cushion. you are starting to understand that these things are a lot of trial and error when you go scratchbuilding. from the ground up, airboats are a whole lot easier to build. but there is something about watching that craft float around like a magic carpet that is way too cool........

Hairball

Amen to that!

rcboatscars

Hairball
you have experienced it huh? didnt know i was quoteable.... shucks fellas

Hairball

Yes, but only with the Tyco Typhoon models. Still very cool.

One of these days I'll get a hobby class one put together.

Big Ted

Just a quick question.

Can anyone tell me what sort of thrust a .049 can put out, and with what prop?

Need that info for weight/surface area calculations

Cheers
Ted

rcboatscars

Ted
no can do. Need someone more technical than i. JB

rcboatscars

Big Ted
go my hovercraft done finally. started the motor last weekend and burned a half tank of fuel thru it. all seems fine. ready for a run. will have pics later on today. JB

rcboatscars

Big Ted

check out this new hovercraft.......JB

Big Ted

that looks pretty damn cool! is that one yours?