« Reply #41 on: May 23, 2022, 4:56 pm »
 
That is a massive achieve achievement with huge experience in Hovercraft. Like Nick indicated,  I am wondering how safe you felt while moving at 142Km/h and overcoming the take-off transition stability and excessive power challenges. I will like to feel the adrenaline moving at such high speed if training is available

« Reply #40 on: May 20, 2022, 12:37 pm »
 
As the sand is hugely abrasive, (obviously!!!), I guess at speed you are basically operating as a wing in ground effect craft?
How you allow for the transition from going slowly to avoid friction over THAT surface and FLYING at that speed is best consigned to people that have more courage than ME! :o
When I get up towards 39 mph, (water only) I need to clench my buttocks so hard, - they go blue.
NOT for the faint hearted, i'll grant you, but they usually ARE covered with jeans, so few women and children require councelling. ::)
Memories are BETTER than Dreams---"Capn" FLINT

« Reply #39 on: May 20, 2022, 8:59 am »
 
No I did the 142.5km/h average. The F16 was my own design, in all I built 18 craft over 48 years ! The second last was the UH18 , only craft I ever did from plans.  Give me your e-mail address and i can send you more photos .Regards, Francois

« Reply #38 on: May 19, 2022, 8:35 pm »
 
Hi Francois, 137.5Km/h is huge. if I may ask, did you design the F16 yourself or it was constructed from existing plans?

« Reply #37 on: May 18, 2022, 5:14 pm »
 
Hi, I was chasing a 1993 speed of Bob Windt, of Universak Hovercraft, when he did 137.5 km/h in one direction over water. Thus I managed to better that by a 5 km/h average, thus a two way run over the same course.   That craft , called F16, was only constructed to see how fast it could go, single seater, narrow cockpit ,was absolutely stable in a straight line, up or down wind.,but I installed an arm rest for the joystick and throttle lever. The trick was to concentrate on holding a line , on a surface devoid of landmarks, for that I planted flags and you go 3 kilometers in the blink of an eye ! Regards, Francois Malan

« Reply #36 on: May 04, 2022, 10:29 am »
 
Thanks John, for the clarification.

« Reply #35 on: May 03, 2022, 1:21 pm »
 
Hi Ombor
Thanks for taking the time to look at the blog. It’s not up to date at the moment.
I couldn’t say how many hours hav gone into the build so far, everything stopped for a while because of illness the the Land Rover needed a full rebuild.
I believe uh used to include plans for the prop, but the eventually stopped including them. My prop is a direct copy of a uh prop, we had a spare one from our other craft, so I build a router copier and that’s how I made mine. 
Hope this helps.





« Reply #34 on: May 03, 2022, 10:31 am »
 
Hi Francois, your speed was quite impressive. I guess the prop is a major factor in UH design more than the material used for the hull construction.


How safe was the hovercraft at that speed and has that your speed record being exceeded?

« Reply #33 on: May 03, 2022, 10:25 am »
 
Thanks John, for the link to your blog. That was an amazing work you did. I thought, the prop plan was part of the UH18 plans, that is if I am right about Fancois propeller construction description, who appears to follow the construction details in the UH plan. It appears you built the prop to different specification. If I may ask how long in  hours did it take you to complete the UH18?

« Reply #32 on: May 01, 2022, 11:27 am »
 
Hi ombor
Perhaps this link might help with information on building a a Uh 18.
My UH 18 build blog is [size=78%]http://hoverwing.blogspot.com/[/size]
The plans I have are not good enough to copy , also the uh plans are crap and you have to make most of it up by yourself.
Hope this helps
John

« Reply #31 on: May 01, 2022, 9:54 am »
 
Whenever I achieve considerable speed, (sometimes accidentally) it take miles to slow down as the friction to travel appears to decrease, and just decreasing power has little effect for ages.
Incontinence pants are needed.
Im MY case- I just tighten the draw strings a little.


THAT is some speed.  :o
Memories are BETTER than Dreams---"Capn" FLINT

« Reply #30 on: Apr 30, 2022, 1:40 pm »
 
Wow! Quite an achievement. :o ;)

« Reply #29 on: Apr 30, 2022, 12:05 pm »
 
What I learnt from the Universal Hovercraft plans, was how to build and balance a wooden propeller. Laminate
20mm sheets of wood by clamps and waterproof glue.  Drill a center hole for the balance rod and work off the
block as per instructions. Shown here is the second high pitch 1.5 meter prop I built to harness the power of a 2.0 liter VW engine.  The other photos show my last craft, F16, built to break the Hovercraft Land Speed record. F16 was 5.5 m x2.2 m and weighed 295 kg. the pointed nose ensured that there was no lift or tuck at any speed. The VW engine drove the prop at 40 % of engine speed, the vertically mounted .6 m multiwing lift fan, behind the seat, ran at 60% of engine speed. Steering was by 3 large rudders.
 On the 7th April 2016, I set a new Hovercraft Land Speed Record , by a doing an average of 142.5 Km/h, about 88 M.P.H. over a measured kilometer, this means a run up and down the same course , within 5 minutes, ensuring that the weather conditions remained the same.  Francois Malan, South Africa

« Reply #28 on: Apr 30, 2022, 9:08 am »
 
There was a limited quantity of them available - we bought 50 sets at a discount. We may have run out, if so we’ll need to have a debate about buying more. Given that we don’t charge for membership currently the conversation may not be the same - not least that Amphibious Marine may be less kenn to offer such a good discount.
Ian Brooks
Gloucester, UK

« Reply #27 on: Apr 30, 2022, 4:09 am »
 
This happened to me too, a second ago. My sub is current until mid June. ??