Failed test flight

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AJW
Posts: 213
Joined: August 23rd, 2014, 4:43 am
Location: Scotland

Failed test flight

Post by AJW » February 5th, 2017, 12:52 pm

I had planned on test flying the Surveyor today for a few miles, but as can be seen in the video it turned out to be a non event.

I only fitted one second-hand part on this craft and it was that part that let me down today :-( "lesson learned, don't be such a cheap skate" :-D

After the last test flight a few weeks ago I have made some alterations. Firstly I have made a new prop shaft as the taper lock let go and the large driven pulley walked along the shaft about 3/4" and scored the shaft. I made a new shaft but this time I cut a keyway in it where the large pulley sits. I left a small amount of play on the key steel as to allow for the taper bush tightening up.

Last time out I only had the hand operated brake, so I made up a foot brake pedal and this was the first time I had tried it.

The biggest alteration I have made and one I was a bit concerned about making, was I moved the partition / divider skirt 12" towards the stern. My thoughts for making this alteration was that my engine is approximately 14" closer to the stern than where it would have been if I had used a vertical shaft motor. Because I used the horizontal motor I also used more metal in the engine frame than there would have been if I had used the vertical shaft motor. By moving the divider skirt rearward I am moving the centre of lift rearward. This does have a downside though, it reduces the craft's overall payload, but not enough for it to be a problem for me.


eccinoz
Posts: 41
Joined: June 24th, 2013, 5:56 am
Location: Oz

Re: Failed test flight

Post by eccinoz » February 5th, 2017, 6:56 pm

Well done Al. Sits very nicely & I'm sold on the Green. ;) Looks great with the black skirt & highlights. :) But the battery, mate,,Fair Dinkum :D

AJW
Posts: 213
Joined: August 23rd, 2014, 4:43 am
Location: Scotland

Re: Failed test flight

Post by AJW » February 6th, 2017, 5:08 am

Still a few jobs to finish now, main ones being the exhaust system as it is way too loud and fit a VHF radio. The lift thrust balance seems about right, so I'm happy with that. The hull definitely sits better than it did with the divider skirt moved back and seems to pick up leveller, instead of nose up first.

The green is a Porsche colour, GT3 green. While driving over the Skye bridge one day I noticed a green buoy on the water and it stood out really well, so I decided I was going green. The GT3 green was pretty close to that buoy colour.

I wasn't going to name the craft but I think I will as I plan on keeping it for a while

gone7
Posts: 69
Joined: February 13th, 2012, 9:54 am
Location: Pagosa Springs, Colorado
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Re: Failed test flight

Post by gone7 » February 6th, 2017, 1:43 pm

Nice Al! Your craft looks awesome. You're right, it levels out nicely at start-up. That was a big jump backward with your partition skirt but apparently it did the trick. I'm kind of wondering though - I know it was just a short test run, but I feel like your thrust is lacking a bit of power. When you turned around and dropped off plane it seemed to have a really tough time pushing you out of the hole again. In fact it doesn't really look like it recovers until you're basically right on the shore again.
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Guy Fichtelman
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AJW
Posts: 213
Joined: August 23rd, 2014, 4:43 am
Location: Scotland

Re: Failed test flight

Post by AJW » February 6th, 2017, 3:02 pm

I haven't measured the thrust, but when the craft is just on hover it is very difficult to push the craft backwards. It is a lot more difficult to push backwards than what my yellow Surveyor was. It took two of us to push it backwards out of the garage workshop last week.

Apparently it is more difficult to get over hump in 18 inches to 2 foot of water than what it is in deep water. Something to do with air pressure forming a deeper hole in the water or something like that.

Anyway plenty of more testing to do to fine tune the craft. I want to check the rear skirt through the lift duct when flying on water to make sure its not scooping water. I had that with my yellow Surveyor a few years ago. I'm pretty sure this one is ok though as I used chalk marks on the floor to make sure skirt contact points were in correct position before making the in fill panels.

I shall keep the videos coming as someone may spot something wrong or have answers for any problems I have with the craft.

AJW
Posts: 213
Joined: August 23rd, 2014, 4:43 am
Location: Scotland

Re: Failed test flight

Post by AJW » February 6th, 2017, 3:28 pm

I just had a quick look at the video I posted in December and on that one the rear end does look lower than the front of the side bags when I'm flying it on the beach. I didn't notice that before, so the divider skirt being moved back has made a big difference to the side view when on hover. Looking at the previous video, the craft did struggle getting over hump, I shall have to tether the craft up and measure the thrust and play about with the pitch of the prop to see what I can get out of it. I still need to weigh the craft as well ;-)

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