How to trim flapped indoor catapult/elastic launched gliders - Protege Lite

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  • Опубліковано 11 лис 2024

КОМЕНТАРІ • 26

  • @josephbolton3057
    @josephbolton3057 5 років тому +1

    That is amazing how those little changes all add up to make it fly so well by itself.

    • @joshuawfinn
      @joshuawfinn  5 років тому

      I never cease to be amazed how it's possible to take something that flies like a wadded up piece of paper, and in the space of one or two test hops, have it soaring perfectly.

  • @GrandadIsAnOldMan
    @GrandadIsAnOldMan 5 років тому +3

    Hope multitasking again there, camera person and mother 😍 Very interesting to watch the trimming process 👍

  • @jamescarr9611
    @jamescarr9611 5 років тому

    Team built your Protege. Tested the CG. It's spot on where the foam and the balsa meet. When hand launching, the glider glides beautifully. The problem is that when launched, the glider doesn't transition from vertical to gliding, it simply dives straight down. What needs to be adjusted?

    • @joshuawfinn
      @joshuawfinn  5 років тому

      James Carr do you have enough right rudder trim to roll it into the glide and enough wing twist to keep it from rolling over? There are at least three different trim problems that can be loosely described by what you've mentioned, so if you can get me video of it I might be able to help more. Joshuawfinn@gmail.com

  • @albertlukas7171
    @albertlukas7171 5 років тому +1

    Very good and very nice glider wing plane👍👍👍👍

  • @gs470
    @gs470 5 років тому +1

    Can you expand on why you added "wash in" to the right wing.? It looks like you are bending the right wing balsa near the fuselage down, apparently to resist the glider twisting (barrel rolling) to the right during high speed. In the video we can't see what was wrong with the transition prior to adding rudder turn and wash in. We are having issues with some gliders that can't seem to transition consistently, often losing altitude at the apex. Launch angle and roll angle not helping. These gliders make a nice level circle during basic level hand throws though.
    When you are adding washin, are the flaps no longer even on the front wing in relation to each other (in your case right lower than left)?

    • @joshuawfinn
      @joshuawfinn  5 років тому

      The washin is done exactly as you described. Pay no attention to the effect it has on the flap alignment. Adding washin helps the glider slide around into the glide better, in addition to resisting the barrel roll tendencies. If you're having trouble with the gliders not transitioning smoothly, it's possible that more right rudder and more wing twist (washin) could help. You may also get some benefit from adding a little up elevator and adding nose weight, as some gliders fly better with the CG moved forward.

  • @ratride1
    @ratride1 5 років тому +1

    How did you obtain access to the school gymnasium? Our local school will be closing after this year. They have two gymnasiums.

    • @joshuawfinn
      @joshuawfinn  5 років тому

      ratride1, a fellow TTOMA member got us access. He knows everyone in that town.

  • @davidfranklin5270
    @davidfranklin5270 5 років тому

    Awesome transitions. I would like to see more of the transition in the video. Attitute, pitch, bank, etc. at the top of the launch. What attitude should we be trying to achieve to minimize altitude loss in the transition.

    • @joshuawfinn
      @joshuawfinn  5 років тому

      Thanks for that. I'll try to concentrate on that the next time we're out flying. We should note that this model is 2.6g, which makes it significantly easier to trim than the 3.5-4g SO models.

    • @davidfranklin5270
      @davidfranklin5270 5 років тому

      @@joshuawfinn I understand. Thanks

    • @joshuawfinn
      @joshuawfinn  5 років тому

      @@davidfranklin5270 Glad to help. I'm looking for constructive criticism to help clarify what aspects aren't getting enough attention so that we can remove as much of the mystery of flying these as possible.

  • @billkuhl442
    @billkuhl442 5 років тому

    Josh what makes for the lighter weight compared to SO Protégé? Interesting you say the SO version harder to trim. The little I worked with it I think I was trying to slow it down too much.

    • @joshuawfinn
      @joshuawfinn  5 років тому +1

      The reduced weight is due to several factors. First, I'm using the lightest balsa I can find for these kits--wood that would be too fragile for student use at the 3.5g minimum weight for ELG. Second, the fuselage is a super light piece of 1/16 balsa with thin carbon top and bottom. Lastly, the flaps 0.5mm Vector Board instead of the 1mm used on the SO version.
      As you noted, trying to fly these too slowly can cause a lot of problems. They also need the CG much farther forward than one would normally expect, and of course the heavier they are, the more rotational inertia they have, making it harder to get the transition to be smooth and reliable.

    • @billkuhl442
      @billkuhl442 5 років тому +1

      @@joshuawfinn excellent explanation Josh.

  • @paulpaulsen7309
    @paulpaulsen7309 2 роки тому

    ... hmm, ... wouldn't it make more sense to make the wing pylon horizontally movable on the fuselage tube?
    Then no trim weight would be necessary...

    • @joshuawfinn
      @joshuawfinn  2 роки тому +1

      The long nose means that any nose weight is going to be quite a bit less than the weight penalty of a secure, movable wing. The other issue is that the tail moment is pretty critical, and if you shorten it to reduce the nose weight required, things can go bad quickly. On high ceiling gliders we do make the wings removable for storage, but still don't move them for balance, only for incidence changes.

  • @rishabhmehta4204
    @rishabhmehta4204 5 років тому

    What do you think is a "good" average flight time

    • @joshuawfinn
      @joshuawfinn  5 років тому

      For Science Olympiad, 20 seconds. For AMA gliders in a site like this, 28-30 seconds is a good target. This model was turning in 28+ seconds by the end of the day.

  • @mariaeduardaoliveira8232
    @mariaeduardaoliveira8232 6 місяців тому

    Good

  • @mycomment4896
    @mycomment4896 5 років тому

    1:58

    • @joshuawfinn
      @joshuawfinn  5 років тому

      This crash brought to you by my son. LOL!