Jerry's Hovercraft Page
Well this summer has been a lot better than the last one, and I have
a lot of fun with this craft.
I was able to take my family on a short trip up the river to nearby
town about 20 kilometers away.
We also stopped in this beautiful bay just off the river. The Bow River
in Calgary, is pretty swift,
so I figure if we travel upstream, we can always float home if we break
It was to the point where nobody wanted to go out with me, because they
expected a breakdown of some sort.
I believe I have resolved most of the problems, and I am getting
comfortable with taking longer trips from home.
The craft looks like a toy in this picture,
but that's me going about 75kph (45mph). I have learned a lot about
some of the problems I experienced with this craft,
and I have also become more comfortable with flying this
It is different than
my UH-10T2/F for several reasons.
- It has integrated lift and thrust (ie one engine
both) This means you can't 'coast' on lift, and you have to be more
about coming off of hover.
- It's much bigger, and you can't use your own body weight
as high a degree. The UH-10T2/F is very playful in this manner, and
to body language quite readily.
- It is too big to move by hand, probably 800 lbs.
This is a shot showing the enclosure I made for the cockpit. The side
will unbutton, and the window unzips for entry.
It helps to keep dry, although as I have improved my piloting skills,
I am getting by with less spray. Still, when you are turning with a
wind, you can easily get soaked!
I also plan to install the heater from the Subaru, so I can drive in
and keep the windows clear.
After being stuck on the water with a belt that wouldn't engage because
loss of tension, I determined to install an idler pulley.
I made it from two idler pulleys from some Ford engines
at the auto wrecker. I bolted the idlers together back to back.
They cost me $3.00 each! You can tell that you've' lost tension, by
the tachometer. If the engine is over revving, and you aren't moving
fast, then you know that it is slipping. The UH method is to install
shims under the pillow block bearings, and remove some from under the
mount, to keep the shaft centered in the duct. You don't want to be
this on the water. It's much easier
to just tighten the idler, though will try to use the UH method for the
of the tension. These kinds of belts are not made to bend backwards,
it will wreck the belt, but hey,.. I don't want to be stuck on the
I tighten the idler with the turnbuckle, and set it with a lock nut.
Things I Learned
- The belts must be perfectly aligned. As the belts went over the
idler pulleys at the front, just before the lift duct, the idlers were
therefore the belt was approaching the front lift pulley on a bit of an
this would cause the belt to roll over.
- When using a variator, careful that you don't apply sudden
pressure to the position of the variator. It could force the variator
pulling against the spring pressure at the back. If this happened
the variator had a chance to 'vari' this would cause sudden slackness
the front belt, and it would come off, or roll over.
discovered that the rear inside corner of the skirt, was
scooping water. It was a small hole, but it would slowly fill up the
rear of the skir. I determined this because if I have plow-in,
all of a sudden
the front of the craft would get real heavy and almost submerge,
as all the water at the back of the craft rushhed forward.
- I installed a slit in the rear skirt with a lace up string in it,
runs to the cockpit. This way, I can drain the skirt in a reasonable
of time as opposed to the five minutes or more it took before. All the
you are trashing your prop as the spray hits it while you drain the
- I overbuilt my engine stand. I made it from .125 square tubing,
of the .083 that was called for. Consequently, I have some serious
issues at the rear of the craft. I estimate the following items have
- Engine stand built too heavy
- Steel drive pulley instead of aluminum
- 13 Ply plywood thrust pulley instead of softwood
- steel 6" pulley for lift drive of aluminum
- It is possible that I could have made the craft tail heavy by
lbs. I just don't know if I have the ambition to build a new engine
and buy aluminum drive parts,...or I could just add 50 lbs to the
but that means you loose 100 lbs over all!
- The primer I used is terrible, and my paint is coming off. Some
the wood is exposed, and I have to look after it soon. I used 'Plastic
but it was a bad choice. I used Marine Enamel for the final coat, but I
have painted it right to the wood and the fiberglass.
- Another big mistake was a misreading of the plans, which led me
build the craft 6" wider than it should be. It would have made it a
easier to handle and trailer, if it was 7'6" wide instead of 8'. On the
hand I gained a bit of lift capacity.
- I forgot to put in a drain plug. I tried to install a bilge pump,
it was made of plastic and broke quite quickly. I need to reslove this,
some water does accumulate in the 'well' at the back.
- Also, make sure the hole(s) through the lift duct for the belt
as small as possible, When I first tried out the craft, I left the slot
and took on lots of water when I stopped too quickly. Now I have
duct tape in very close clearance to the belt, and it works well.
- I need to improve the leading edge of my thrust prop. It gets
each time I go out. I didn't want to spend $150.00 for a role of 3M
edge tape' (aka helicopter tape), so I ordered some tape from Aircraft
for $20.00 role (US). The
is that the tape provides a slight cushioning for the front surface. I
used clear athletic tape in 2 or 3 layers, and found that it extended
life of the leading edge , though the tape didn't last
long. I was hoping this new tape would be the answer, but
it wasn't a lot better than the cheap athletic tape.
Comments or questions
page | UH16
Thrust Duct , Props and Fans | UH-16
2 | UH-16
3 | UH-16
4 | UH-16
5 | UH-16