The Cyber Parachute Surfer.
This page is based on a report I posted to http://groups.yahoo.com/group/allrcparaplaneandparagliders/
In my quest for an
aerial camera platform I've tried several fixed wing models and a
couple of micro helicopters.
A few months ago I got interested in the sky-surfer (a model paraplane).
Paraplanes are steerable powered parachutes. They are usually a ram-air parafoil. The advantages I can see are - easy transport and storage, low flight speed and crash worthiness. They are easy to fly and easy to see.
The down side is they are more or less constant speed (adding power makes them go up but not go faster) and can have trouble fighting wind. The gondolas often swing which is bad for photography and they are the prefect design for getting stuck in trees and so forth.
I think the s/surfer
was selling for $300US at
the time and I put off buying it for a while. When I decided to get
one (listed at $250 now) I found that they were discontinued.
I had already found a cheap copy on this site. http://www.raidentech.com/cypasurareco.html
This model seemed to be either a “sky surfer” clone or a re-badged s/surfer. The add shows a picture of a s/surfer with s/surfer marked clearly on the canopy.
The price –$55
US !!! (currently $39.95 in march 2007)
With post to Australia $100 US or $130 in Aussie money.
Looking around the
site I was suspicious that it may have be a fraud. I looked for
reviews of raidentech on the
web. I decided they were for real and ordered my model.
Then I found the review site I was looking at had sorted the reviews to put the best first and that all the ones I hadn't read were extremely negative. The reviews were a few years old and I crossed my fingers that things had improved - seems like they have.
Apart from not automatically sending a tracking number I have no complaints about the service. The package arrive about 8 days later which is about as good as it gets.
I opened the box and my first impression was that it was a heap of junk.
The canopy is mylar (or similar) bonded onto soft foam ribs. Someone else said it looks like shopping bag material and it does. Some of the seams were coming apart. The leading edge and line attachments were with fibre tape which was lifting in places. The gondola looked quite reasonable though. I was expecting the model to use brake steering but it doesn't. I think four line chutes usually have the front line fixed and the rear lines are pulled for steering. In this model all the lines go to the servo one way on another.
was easy enough.
The spreader/stiffener seemed to be too long. I used it as is but I was uncomfortable with the amount of strain on the seams and the amount the end ribs were bulging. I cut a few centimetres off before flying.
Initial power up showed two problems.
The first is the servo doesn't seem to work properly. Once moved it doesn't centre properly - but I figured was good enough for now. The problem might be in the transmitter not the servo-motor - I don't know. The servo is also very slow.
The other problem was the motor would not run properly if power was applied too quickly - again it would have to do. Also the throttle sux, it is spring loaded to centre - which is off if trimmed neutral.
On Saturday I went to Nimbin where I have a share in a property - I do most of my crashing and flying there. The wind was nil and I carried the rigged model out in a paddock of knee high grass. I would not have been surprised if the thing tore apart in a matter of seconds but it didn't.
I couldn't really get
the canopy to be level when I tried to throw it but launched it
anyway and surprise surprise - it flew - but only just.
The thing could barely climb.
I'd get it to head height but loose it on the turns. It seems to steer ok more or less, there was a big lag in the steering but I could keep it in the area ok. I did a couple of short flights like this and went and changed the battery. I changed the connector for a micro-deans like my other gear and changed from the supplied 6 cell 600mAH Nicad to a 1200mAH 2 cell lipo. The lipo is a lot lighter.
The difference was remarkable. I launched as before and the thing banked steeply to the right and crashed hard. I checked to see if the rigging looked even, it did so I tried again. It crashed. I hadn't figured out why at that point and trimmed fully left. I launched and hit left stick as fast as I could and managed to clear the ground and climb to a reasonable height. Then it stared to spiral down again under full power. I managed to recover somehow (probably by pulling power) and climbed away. I had full power and almost full left stick to keep it more or less level. I climbed to maybe 150 meters and pulled power and brought it back without any trouble. I decided to quit while I was was ahead and carried it back to base. The rigging looked fine so I figured all the problems with steering is simply motor torque pulling the lines down on the right. I haven't heard anyone else mention this but it is an obvious issue. We could do with a "revo" style mix in the transmitter to compensate.
I was in a meeting most of the day and couldn't try another flight till about 2:30pm. There were dark clouds about but only a puff or two of breeze. I almost crashed on takeoff again but regained control when I pulled power. I climbed under full power a little bit then found that full throttle trim and hands off was enough power to climb slowly. I reduced power some more at 100 meters or so. I still struggled to keep it under some sort of control and when I managed to bring it overhead at say 80 meters I notice the gondola was giggling. This was without control input and it didn't look like turbulence was doing it - but it may have been. It is possible the gondola is too light with the lipo fitted. I tried to do another circuit but notice it was now going backwards. The breeze on the ground had sprung up to 5 knots but obviously more at height. I pulled power and *tried* to keep it pointing in my direction hoping the wind lower down would be kinder. The model got smaller and I couldn't judge whether it was over the trees or not so I kept it flying and managed to steer it into a clear spot and pulled power again. It landed itself about 200 metres away and doesn't appear to be damaged.
So - I think I got my money's worth. Ultimately I'll probably build something (if I find the time). This is the cheapest outdoor model I've ever bought and also the first I didn't break on the first day. I don't expect it to be my camera platform but it has already taught me a lot.
You can see a plastic gizmo which clips onto the servo arm. The green lines at the top are the front strings to the canopy. The rear lines (which are pink) have a flexible nylon line attached. This passes through a hole in the frame and clips into the zigmo. You can clip into one of five holes to adjust the AOA (angle of attack) of the canopy.
The manual for the sky-surfer can be found here. http://homepage.sunrise.ch/mysunrise/rc-skysurfer/skydownloade.htm
I found a video add for the cyber chute somewhere but I can't find the source again - so I've put a copy here - I'm sure no-one will mind. The slow frame rate at the end is in the clip so don't blame your computer.
http://www.seabreezeparachutes.com/ is also worth a look for custom made canopies, video clips and more.
I'm exploring using a kite as a replacement canopy and Dave from http://www.freespiritkites.com/system/index.htm has been very helpful.
Skysurfer and other clones.
The genuine skysurfer
and canopies are still available from the “green corporation”
Unless you know Japanese, there are language problems in dealing with them. They couldn't accept electronic payments but were looking into using paypal when I last heard from them..
Their web-site and email is currently dead but hopefully will fixed - http://www.green-jpn.com/
There is some debate as to how the quality of the genuine surfers compares with the clones. I have ordered a couple of genuine canopies so I will able to see for myself.
I've been informed there is a clone called a “paracopter” (stupid name). These are selling for US $29.95 on ebay (March 2007).
There is also a clone by e-supply.hk
I have no idea of cost or quality of this model but they do have a nice video of it flying. I emailed seeking permission to post this video and they haven't said no, if fact they didn't say anything. It is about 8 meg.
It is quite possible
these clones infringe on skysurfer's patent or copyright. I don't
have the facts and can't comment on this.
These issues aside buying a clone is a cheap way to get a taste of this type of model. I think a clone with a genuine SS canopy could be a good compromise. Most (not all) cyber-chute owners seem to think they are worth the money but you shouldn't assume that it is a good as the genuine item.
It seems like it is quite practical to upgrade these will better RC gear and motors.
Last year (2006) I
managed to get a couple of genuine sky-surfer canopies but it was the
most painful internet shopping experience I've ever had.
By the time I got them I had converted my homebuilt to using a kite. My original cyber-chute canopy still works so the new chutes haven't flown – they will when the original fails.
My models page is here and my home page is here.