[photo]

Anthony's Lifting Messenger -- Responses

Responses from people


The following are responses I have recieved from the network about this plan. This makes interesting reading and some of the results have been incorperated back into the main plan.

Many thanks to all who have replied.

 

David Hunt <davidhunt@washington.xtn.net>, on 4 December 1997, wrote...
I just recently initiated a study of kite messengers to determine the most efficient design. My daughter is using part of this as a science fair project for school.

Our first messenger uses a body of .25x.75 inch spruce approximately 16" long. Along the top side(.25" side) a piece of aluminum tube (model airplane fuel line) just large enough for 1/8" diameter rod to slide is duct taped. Tubing is taped underneath to constitute the release mechanism. I use the front stop arm as the front hanging point.

I do not use a folding sail, instead I have a semi-permanent 1/4" wooden dowel three feet long hung underneath the wooden support toward the forward end of the messenger. The dowel sticks out 1.5' off each side. The sail is made with a large pocket that slips over this dowel, two short dowels are attached using small pockets at diagonals like the "genki sail" shown on your web site however there are no vertical supports. The sail is held in position by lines attached to the lower outside corners and then to the release. When released the sail flaps about the upper horizonal 1/4" dowel. Flaping definitely slows the return of the messenger. By adjusting the length of the release lines the sail's angle of attack can be changed.

We have only tested two angles so far the first was with the sail perpendicular to the body of the messenger the second with the sail 45 deg. to the body toward the rear of the messenger. We also attached various weights to the messenger to measure its lifting ability. When I have some hard numbers I'll forward them to you.

Anthony's Reply :- This is great. Note that the sail angle would also depend on the angle of the kite line. I myself am more interested in near vertical lines which would mean that the messenger itself has to support the load. In fact I will be continuing my studys on and off into the future.

Jeff Hylton <hyltons@mailprime.tidalwave.net>, on 4 December 1997, wrote...
Thank you for the wonderful discussion on your lifting messengers.

The diagrams were very clear. I experimented with a few variations on messengers and came to the same conclusion: A kite was the ideal sail. I fly Conyne deltas and they stay very high. I had to build a messenger that I could change the attack angle on so the sails would even show to the wind. It still needed a gale wild to pull up my load (disposable camera). I couldn't figure out how to mount the Diamonds. Your double spine is a great idea.

So...diagrams and detailed instructions in hand I will try out your ideas. Maybe I can get something together before spring. Of course I'll have to modify the plans for no good reason. I'm thinking of two small Diamond kites hinged together. That will create a horizontal hinge and get rid of flapping once they flop back. We'll see.

I'll let you know if I have any success! Thanks again for the ideas.

Famille SCHERRER <p.c.Scherrer@wanadoo.fr>, on 25 April 1998, wrote...
A friend of mine give me you web adress : What an interesting site !!! I enjoy as much the technical side as Tuffy's parachuting adventure (my little sister too...) It is very pleasant to read, it is precise and it works !

[photo] My friend was the first to built your messenger, and he was quite happy with it. So I decided to build mine, in order to carry small radio-controlled sailplanes.

Even if a sailplane doesn't act as a "dead load" _ it provides drag and little lift as much, because the radio-controlled release hook is situated in the nose, and it present a certain angle to the wind and is like a part of the sail !!_ I have made a bigger messenger (size x1.5).

I have not yet tried to lauch a sailplane (the weather is so bad in france those time...), but only dead load, up to 200g, without any probleme. The kite was a Cody (about 2m). I will writte you latter the result of those experiments.

Sorry, this are no "outdoor photographs", and my room is quite busy those time. But believe me, it is not only a messenger in armchair, it also flew in the storm and carried heavy payload !!

Anthony Thyssen <anthony@cit.gu.edu.au>, on 2 May 1998, wrote...
I found some large `cotter pins' in a marine shop. This was made from very thick round spring steel. After a using a vice and big pillers I managed to bend the stell in a shape simular to that given for the coat hanger wire in the messenger plan.

This was the original outline...

  ___
 /   \
|     |
 \    |
  \   |
   \  |
    | |
    / |
      |

I bent the loop even more so, so that it crosses over, and inserted it into plastic tubing for attachment to the messenger body, in a simular way to the normal coat hanger wire.

  ___
 /   \ 
|     | 
 \    |
  `---|-.
      |  \
      |
      |
      |

This pin did not bend very easily and required the use a vice to hold while this was done. It isn't perfect, but is better than the use of coathangers. In any case the 3mm round wire does not seem rust, or wear and is very shiny and smooth. If fact it slides extremely well!

Anthony

Ivan Simard <isimard@mediom.qc.ca>, on 8 December 1998, wrote...
I built a messenger that got his first flight this afternoon.

I am glad to tell you that it work pretty well ! The wind was low with some moderate gust. Nothing to break the thing. In fact, when the wind die down, the messenger get down very slowly. So i think it is well calibrate for medium wind, just what i wanted.

So now that i know that it work, i will continue on making a parachute for my doggie, but i intended to keep it light. I don't mind if it come down fast as long as it can get up !

[photo] [photo] [photo]

So, thanks again. You can say that there is a clone of your mesenger flying in Quebec city, Canada, on the Plaine d'Abraham today, on a snow covered field. It look good and it put a very big grin on my face. In fact, it made my day ! I am looking forward for next summer when there will be somebody else on the field, just to listen to their comments and grin ever more !!!

Anthony's Reply :- Hmm pretty good. I gather the sail is a type of plastic?

In that case you didn't need to fold it over around the edges. Also I can now using a fishing clip to clip the two top edges of the line slot together once it is on the kite like. This stops the double spine bending so much as can be seen on yours.

I myself have bever used epoxy, so don't have esperience with it. however I am using a `hot glue gun' for some things in my kite design. A little hot glue before putting plastic tubing on means it will definately not come off again :-)

Patrick Mann <patrick.mann@bigfoot.com>, wrote the following on one of his kite pages
Later I came across Anthony Thyssen's kite ferry page. Anthony had the brilliant insight (so obvious, in retrospect, yet I have seen no prior references to this type of ferry design) to use a sail based on an Eddy kite, thus endowing the sail with a lifting capability. Now that I come to think of it, this is comparable to the Cody man-lifting system: Cody's system also used separate kites to tension the guide line and to actually lift the "payload".

The advantages:

In addition, Anthony's design does not require any sail retraction mechanism.

So I have replaced the sail on my ferry with a new version based on Anthony's plans. Preliminary tests have been very satisfactory: it rises beautifully and promptly returns after releasing the payload. I still have to make some minor improvements to the self-adjusting hinge and to build a larger sail ... but I am confident that this is finally a ferry which really works well.

Again many thanks to all who have built this messenger (or others) and responded. Especially those which included any hints and tips they found and contributed.

-- Anthony Thyssen.


Created: 4 December 1997
Updated: 9 May 1998
Author: Anthony Thyssen, <http://www.sct.gu.edu.au/~anthony/mail.shtml>
WWW URL: http://www.sct.gu.edu.au/~anthony/kites/parafauna/messenger/