Model Boat Mayhem

The Shipyard ( Dry Dock ): Builds & Questions => Pleasure boats, Sports, Race, Power and Leisure Boats: => Topic started by: john54 on March 18, 2008, 06:05:14 pm

Title: Air Boats
Post by: john54 on March 18, 2008, 06:05:14 pm
Hi
Has anybody had any experience with air boats?
I would like to build one or  convert a ic one to leccy about (30in ish)
Any ideas or is there anybody on here who has one up for sale ect.
Title: Re: Air Boats
Post by: tobyker on March 18, 2008, 10:53:52 pm
Check out the gallery on canadianairboats.com for lots of helpful pictures of the real thing. The rule for easy steering is chines sharp forrard, rounded aft. See especially the double engined 30' by 15' workboat - that could be quite good fun. I've got an 18" one with the smallest budget brushless motor and controller - there used to be film of it on YouTube.
Title: Re: Air Boats
Post by: Martin (Admin) on March 18, 2008, 11:42:00 pm
I've had a couple of air boats, great fun, very fast!

Sod to turn if you only have "air rudders!"
One of mine once did a complete ' back flip' somersault off a wave and carried on going!
Title: Re: Air Boats
Post by: Big Ada on March 19, 2008, 05:22:36 pm
I built this from the inards of an electric plane I could't fly.
Its an own design.
Title: Re: Air Boats
Post by: Welsh_Druid on March 19, 2008, 07:46:22 pm


Sod to turn if you only have "air rudders!"


NO NO NO  ;)  Have a look at this video of mine - its turns in its own length !

www.Durnfords.co.uk/Airboat.wmv    ( its 4072KB so may take a while to download)

Don B.
Title: Re: Air Boats
Post by: Martin (Admin) on March 19, 2008, 08:51:37 pm
That thing is hardly moving Don!!! At speed air rudder airboats steer like hovercraft!  {-)
Title: Re: Air Boats
Post by: john54 on March 20, 2008, 04:21:29 am
Thats the sort of thing iam after but will use brushless.
So where can i get the plans from or even a hull ?
Title: Re: Air Boats
Post by: Welsh_Druid on March 20, 2008, 09:44:54 am
Thats the sort of thing iam after but will use brushless.
So where can i get the plans from or even a hull ?

Its scratch built - despite what Martin says it WILL go much faster  {-)  My friend was wary of giving it full throttle whilst I took the video.

Basically its just a block of polystyrene foam, 60cm x 30cm x 65mm,  cut with a slope up to the bows underneath, a compartment cut out  for the battery and another for a watertight box for the controller and rx.  Motor is a 500 driving a 9" prop through an MFA belt drive gearbox on 8.4 volts. Balanced about two thirds back from the bows.

The foam is covered on the sides with balsa sheet and the bottom with thin styrene sheet to let it run up the slipway without damage

Don B.
Title: Re: Air Boats
Post by: Big Ada on March 20, 2008, 04:56:42 pm
Hi John54,
There was a free plan not so long ago in one of the uk mags.
Look out in skips for old surf boards or similar.
Len.
Title: Re: Air Boats
Post by: tobyker on March 24, 2008, 03:20:13 pm
Properly designed air boats turn in their own length at speed with air rudders only. But they must have plenty of top weight and a hard chine forrard, round bilge aft so they heel and the chine digs in when they turn. see if Toby's airboat is still on youtube.
Title: Re: Air Boats
Post by: Selph Inflicted on April 20, 2008, 07:35:02 am
I build and manufacture my own line of airboats.

We have GPS-ed one of my boats at 53.3 mph, with an OS61FX running an Ultra Thrust Pipe
"Selph-Inflicted" 3 Pt Hydro Airboat hitting 53.3 mph. (http://www.rcairboats.net/Videos/Others/Nitro/Nitro533.wmv)

We also got 49 mph with an OS46AX running an Ultra Thrust Pipe
"Selph-Inflicted" 3 Pt Hydro Airboat hitting 49 mph. (http://www.rcairboats.net/Videos/Others/Nitro/NitroSI4946FX)


I'm not much of an electric fan but I have a client that is going to try an electric version of this in about 2 weeks or so. I'll let you know how it turns out.
Title: Re: Air Boats
Post by: Martin (Admin) on April 21, 2008, 12:02:50 pm
Is it me or do Airboats seem faster that 'normal' boats with the same size engine?  ???
Title: Re: Air Boats
Post by: tigertiger on April 21, 2008, 01:34:09 pm
I assume the airboat would have less drag. Even though a subsurface prop is thrusting, it will have drag. The airboats prop also has drag, but air is less dense.