Early Adventures with the Hovercraft
Things don't always work out as planned. I had decided that as I was only getting about 22mph out of my UH13PT I should alter the skirt to make it more efficient. I had noticed that the rear skirt seemed to be about four inches longer than the sides, so I adjusted the rear section, tucking in the extra material in case I have to make further adjustments. I also changed the front end to try to get rid of the excess length of the original design. I spent a couple of days playing with it and it certainly looked great as it stood on blocks.
I also carried out a couple of improvements, making the rear seat a bit longer, and also converting the steering from cables to a torque tube design, and adding a training stick for the rear seat person to play with. Adding a couple of power outlets, and foam to the sides kept me busy for several weeks through the winter and spring.
Anne hovering in the UH13PT after a run up the Platte River from the Hwy 92 bridge near Valley, NE
Testing - River or Lake?
We waited and waited. First it was a case of too cold, then too much ice, then flooding. Plan B was put into operation which was to make use of the local `free for all' lake where the jet skiers, water skiers and every other type of boater played around. The local lake is Manawa, which is actually much nearer than the Platte River. I was not too keen to try out the lake as it is so busy most of the time, but my friend Dean, decided to test his UP17P there as we were now just days away from the Muscoda Hover-in. Another friend Pat, was also there to help out. Seeing Dean out on the lake overcame my reluctance and so Anne and I drove back home to bring out the UH13PT. It was already loaded on the trailer and hooked up to my trusty VW Vanagon so we were back in no time at all.
Dean testing out his hovercraft on the Platte River, NE
With help from Pat and Dean, I had the hovercraft into the water, carefully avoiding the sunbathers, and only starting the thrust engine once I was safely away from everyone. It revved up easily and off I went. The water had a swell, which varied between six and eighteen inches. The rolling motion was disconcerting at first but I soon got used to it. More disappointing was the lack of performance. I was expecting something better than before, but now I was on the plane but still throwing out a bow wave actually it was a "1/3 down the craft" wave. It was not there last year so I guess my careful skirt adjustments were less than an improvement. I still had a good time out on a lake for the first time, but it didn't feel as good as the river outings.
We were enthused about going to Muscoda just a week later. It was the 2nd time I had taken the UH13PT there. The first time I had a prop hub problem that stopped me getting on the water. We ended up being onlookers.. This was going to be the real deal. I'd put 5 hours on the craft the previous year and now it was time to have some fun!
Lined up with the other guys. My UH13PT in the foreground, with Dean's craft just behind, then Jerry Glomski's Yellow Jacket, and several more excellent hovercraft - all ready for the river!
We arrived on the Friday afternoon with time to get off the ramp and into the Wisconsin River without too many spectators. The ramp looked challenging, with some vicious lumps of concrete waiting to tear up the skirt of any craft drifting off the ideal line. I got some assistance from Pat and Dean who had also come along, with Dean's hovercraft, and managed to get off the ramp reasonably well, or so I thought. I had 30 minutes of fun, practicing turns and maneuvers before I had to land and get some dinner. I caught the skirt after all, when I stopped the craft on the slope after landing, and ran over it with a skid. Before I settled down for the night I patched the couple of small holes.
The following morning was perfect, and I took off for another play up river, before coming back to take Pat, Dean, Anne and Steven, a ten year old who was camped beside us out for rides. It was Steven's birthday, so I gave him a long ride up the river and back. The training stick came in handy for everyone as they could steer the craft from behind.
Each time I cane back I was able to put the craft on the sand just below our campsite. Nick, Steven's dad, had brought a vintage amphibious car along and had taken it out into the river a couple of times. He offered to take Anne and me out for a ride. It was to be a first in more ways than one. As we entered the river we bumped along the bottom until we got into deeper water. It was strange sitting in a car in the river, with the water just inches below the edge of the convertible's sides. All went well until we tried to climb up onto a sandbar across the river, to help out another hover pilot who had been caught by the landing ramp's teeth on her launch. The car got high sided on the steep edge of the sandbar, and we climber out to actually push the car whilst still in the river - certainly another first! With the help of another couple of hovercraft pilots we finally managed to get the car back into deeper water. The offer of a ride back on one of the bigger craft was too hard to refuse, and we got back before the car landed again.
After more playing on the river, we all joined in the BBQ and after another quick outing relaxed though the rest of the evening chatting with other hover-nuts, and enjoying "smoores".
Sunday was another perfect day and Anne and I went for another cruise and I had time to play again, before we loaded up the trailer to head for home. All in all, it was an excellent weekend, marred only by the problems Dean was still having with his hovercraft. The consensus was that the machine was too heavy. Dean has decided to fit something lighter to solve his problems. Back to the drawing board!
The journey to Muscoda is well worth the effort. If is a 850 mile round trip, but we'll be back. It is a pity that the second hover-in there is only about six weeks after the first one. If there was on in September then we'd be heading back. As it is, we'll be there next year.
On the River Again - Almost!
I wanted to get onto the river the following weekend, and we headed over to the launch site, only to find that the river was high and fast. Actually, I expected it to be that way, as I had found a website with real time rate of flow and river level information. The river was running at over 13,000cuft/sec and was too high to go out; at least for a wimp like me.
By the next weekend the river flow had dropped to around 7500cuft/sec. Anne and I decided to head upriver to see how far we could go. We managed 10 miles, getting as far as Fremont and only time limited us going further. We toured a different channel on the return journey. The craft was still running about 8mph slower than last year, but we still used around two gallons in the two hour outing. After dropping Anne back at the launch site I went out again for another forty minutes, just playing around on and off the sandbars, and throwing 360 degree turns, and enjoying the snappy performance of the craft as a single-seater.
On the Sunday I spent the afternoon adjusting the skirt to remove the irregularities. By the evening I think I got the skirt looking more like I think it should be. The test will be this weekend. The river flow is slowing fast, with Friday evening showing flows as low as 750cuft.sec. I'm guessing that it will be around 1,500cuft/sec. by mid afternoon. I'm hoping that we get the speed back to around 25mph, and intend another trip up the river â€ï¿½ we carry six gallons, so we could manage almost another two hours each way. Or we may have friends stopping by and do rides instead. Either way it will be fun!
I'm also working on my second hovercraft. I am currently making the lift and thrust ducts. I have also made up a new thrust propeller for the UH13PT - the quest for more efficiency continues.
Kevin
06/28/07
Saturday June 30th
We got to the Platte River about noon and five minutes later a friend, Gady, who had phoned me a couple of days earlier about hovercraft building arrived for a ride.
We soon had the UH13PT off the trailer and ready to go. We revved up and shot of down the ramp. As I got out on the river I realized that I had kicked up a huge cloud of dust. Oops!
Out on the river we had a blast. I put the machine though its paces and Gady signaled that he was having fun. I did a 360 and continued ahead, and then let Gady take over using the dual stick. We stalled in a turn and Gady got the shower treatment! I set us back on the plane and we headed further up the river. I settled on a sandbar so that we could chat about the experience before we headed back to the ramp.
As we stood talking an air boater can towards us and pulled onto the sand beside us. Expecting the usual friendless I was shocked when the guy started ranting and raving at me. Realization set in as he complained about my exit from the ramp area. I had unthinkingly started up on the gravel, instead the concrete ramp, and thrown dust and stones toward his parked airboat and truck. I was mortified that I had done such a stupid thing, and I repeatedly apologized He was not a happy man, but I fully understood his point of view. I had been totally inconsiderate, and I felt like a complete idiot. He took off only slightly less unhappy, but I resolved to never be so careless again. It is easy to forget that our air cushion vehicle does have a downside, when on dust or loose material. We owe a duty of responsibility to avoid sharing this downside with other people, so be careful when other people and craft are present. No more stone throwing for me.
Gady and I headed back to the ramp and after more chatting Gady headed off to plan his own hovercraft. Anne and I loaded up and took off up the river. I had parked the craft on the ramp, so as not to repeat my stupid mistake twice.
On the brighter side, my efforts to improve the skirt had paid off. We could both feel the difference. The performance had improved so that I could get about 19mph on the water and 22mph on the sandbars.
We picnicked on a sandbar on the way up the river. The water lever had dropped greatly and the river was now a maze of channels. I used the GPS to keep in the main channel and we kept heading north. It was only when I downloaded the GPS track back at home that I found we had traveled almost as far as North Bend, almost 25 miles up river. We had a great time. On the return trip I got more adventurous and started crossing more and more sandbars. I had to be careful not to get caught out by the drop offs on the downriver side, but we did shoot over drops up to about 8 inches. When the drop was into water the craft took them with ease, and were a blast. However, occasionally, I got caught dropping off onto sand, which was less forgiving. The craft did take both with no damage, but I did worry about overdoing it, and tried to read the surfaces as far ahead as possible.
We saw eagles, and turtles, and waved at the airboaters, and paddlers along the river. Everyone is so friendly on the river. Even the guy I had upset waved at us (at least I think it was a friendly wave) as he passed by the ramp later. I want to stay friendly with everyone and let us all enjoy the river together.
Again, we stopped on a sandbar to stretch our legs. And I got out to check out the skirt. It is easier to see any gaps when it sits on the sand. This time as I got out, leaving the thrust and lift engines idling, I was delighted to find that the craft started to drift across the sand. In the past, it had too much friction to do this, but the adjusted skirt was far more efficient.
After dropping Anne off on the ramp I headed out solo to play. The craft was a little stallion. Found I could achieve 25mph on the water and even faster on the sandbars. There was a slight problem at the higher speed where the craft felt like it wanted to deviate from the straight line. I suspect that I still have a few wrinkles under the skirt which may be catching the water at the higher speed. I'll check it out before the next outing.
As I was waiting to get back on the ramp, I stopped on a sandbar opposite the ramp near to an airboat. The pilot, Chris, skimmed over to take a closer look at this craft which skimmed the sandbars with ease. We got talking and Chris offered to take Anne and me out for a ride. We jumped at the offer, and had a great ride down the river for several miles and back up again. I can see why lots of people enjoy airboating. It is fun! We stopped to chat with more of the airboaters before heading back to Omaha for some dinner.
After we finished eating a local fire fighter came across to chat about the hovercraft. He was intrigued by the idea of hovering and delighted to hear that the machine could be built for around $1200-$1500, including engines. I gave him my card and he said he'd be emailing me for more details. We would be delighted to have more people interested in either building or buying and operating hovercraft in the area. The Platte River is idea for hovercrafting, as the sandbars are no real obstacle for us.
