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ArnoldMark
25-Nov-09, 10:56 AM
Hello guys,

I'm from Holland and need help with my school essay about hovercrafts,
i want to compare the costs of Hovercrafts with other boats,
So i need to know some stuff:
1. How much gasoline uses a Hovercraft pro km or hour,
2. How much does it costs to store a Hovercraft? And is there any kind of need for a other storage as other boats?
3. Wich kind of gasoline uses a Hovercraft and how much does that costs?

Sorry for my bad english, trying as hard as i can,

How more reliable the source, the more i can use it,

With kind regards,

Arnold

Jon Pert
25-Nov-09, 11:19 AM
Hi Arnold,

1, This is really difficult to answer as there are so many things that can affect fuel consumption such as: wind speed and direction, cruising in a straight line or making many turns, type of engine. Hopefully some of our members could give figures for their craft/engines and you could take an average. I can't tell you mine as it isn't built yet and the racing craft I used to race would not give a fair comparison!

2, Depending on size it can cost as little as nothing! It can be stored in your garage or in your garden! If you do not have the room then you would have to rent a garage or space at a marina. I have no idea what that costs as mine is stored for free at my work!

3, Light hovercraft use petrol. Over here petrol currently costs about 1.10 per litre.

Don't worry about your English, it's better than my Dutch! :)

ArnoldMark
25-Nov-09, 11:49 AM
Hi Arnold,

1, This is really difficult to answer as there are so many things that can affect fuel consumption such as: wind speed and direction, cruising in a straight line or making many turns, type of engine. Hopefully some of our members could give figures for their craft/engines and you could take an average. I can't tell you mine as it isn't built yet and the racing craft I used to race would not give a fair comparison!

2, Depending on size it can cost as little as nothing! It can be stored in your garage or in your garden! If you do not have the room then you would have to rent a garage or space at a marina. I have no idea what that costs as mine is stored for free at my work!

3, Light hovercraft use petrol. Over here petrol currently costs about 1.10 per litre.

Don't worry about your English, it's better than my Dutch! :)

Thanks for the reply, but for point 2: In Holland the most people have to pay for the storage of there boats because they have no space to do it there selves. So the most important question of that part is: Does a hovercraft needs special treatment to be stored or will a normal storageplace be fine?

John Robertson
25-Nov-09, 01:12 PM
Thanks for the reply, but for point 2: In Holland the most people have to pay for the storage of there boats because they have no space to do it there selves. So the most important question of that part is: Does a hovercraft needs special treatment to be stored or will a normal storage place be fine?

The answer is no - in fact, storing a hovercraft should be easier as it doesn't need a trailer and can be moved around on land under its own power.

It is very difficult to give an average fuel consumption as there are many factors involved. I would suggest you use load/speed/power to give a rough comparison (for example, a 4 seat hovercraft travelling at 40mph would need around 72hp, a 4 seat boat at 40mph needs 100-120hp). As fuel consumption is a function of power output, the hovercraft would consume around 28-40% less fuel than the boat.

Ross Floyd
25-Nov-09, 02:01 PM
My 2 seat BBV2 with a Rotax 503 ( twin carb/twin mag ) and solo 210 would use anything up to 7 gallons/hour - but usually about 3 for normal cuising. But it did go quite fast!

Our 'new' BBV3 with a Honda 8.5 lift and B/S 35 thrust burns 1.5 gallons/hour in most conditions.

You may find some useful information and photos on our website http://www.farvis.com/hoversrn4.htm

Best regards,

Ross

gavinparson
26-Nov-09, 09:41 AM
Thanks for the reply, but for point 2: In Holland the most people have to pay for the storage of there boats because they have no space to do it there selves. So the most important question of that part is: Does a hovercraft needs special treatment to be stored or will a normal storageplace be fine?

This is a valid consideration. I have always had problems with storing craft and have had to rent storage facilities in the past.
If the thrust fan duct or propeller is over 2 metres high it will not fit into a standard garage. A 2 seater craft with a 900mm duct will just fit through a standard garage door. In the UK a standard garage is also around 16ft long (4.9m), a similar 2 seater craft on it's trailer may well be 4-4.5m long on the trailer. A larger craft will therefore probably not fit into a garage this size.
Also for a given length a hovercraft is quite wide. Craft under 4m long will be only 2m wide. A longer craft will be wider than this and may not fit through a garage door and would either need to be stored in a larger building or stored outside.
A craft over 8ft wide (2.46m) in the UK would need special arrangements for transportation including a police authorised escort.

Hope this helps.

Gavin

John Robertson
26-Nov-09, 10:34 AM
Why not store your craft at a boat yard just like boat owners do ;) I know a couple of people who do exactly that. A hovercraft doesn't need to be stored inside a building.


A craft over 8ft wide (2.46m) in the UK would need special arrangements for transportation including a police authorised escort.

Not quite - trailer law (like a lot of UK law) is horrendously complicated! Loads over 3.2m wide need to notify county police two weeks in advance (they don't need an escort though).

In the real world, for most "domestic" vehicles you are limited to a trailer of 7m x 2.3m weighing no more than the vehicle manufacturer tells you it should. The 7m length does NOT include the hitch or drawbar and, if the load can't be split (a hovercraft!) then you are exempt from the 7m length (glider trailers, etc but NOT from the weight limits).

Your "load" (the hovercraft) can overhang the trailer by 305mm PER SIDE and 1-2m at the rear (if you tie a warning rag to it) or up to 3m at the rear if you put a light board on the load.

All this means that you can quite legally tow a 10m x 2.9m hull size hovercraft on UK roads (with a trailer load bed of 7m x 2.3m).

It is perfectly possible to make a hover trailer/load combination weight less than 750Kg (easy for small craft) and, provided your tow vehicle weighs at least twice the trailer laden weight, you don't even need to fit trailer brakes (I used an unbraked 8m x 2.3m 700Kg trailer for years)!