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Re: steve's dragon 13 Dec 2013 00:08 #770

>think about what sort of air you will be flying in?..think like a
> pilot...when its 5 or 10 meters per second up, it would not matter what your
> sink rate is..do you realy need moor wing area?

I thought the whole point of this micro-lift was that with really low wing-loading and sink-rates you could take advantage of the micro-lift. If you raise the wing loading (increased weight), wouldn't the sink rate rise as well? Additionally, I don't think this is a machine that has extraordinary penetration capabilities, so I'm thinking it would be flown in relatively calm days. I Would hope to be able to take advantage of that effect anyway.


> nearly all these gliders ,once finished are heavier than what the plans state, any add ons may take you over your countrys limit.

That's probably true. My intent would be to pick over the plans to see where some weight might be saved. This is actually what I do for a living. I've been doing stress analysis for a bit more than 26 years, so I'm confident that there may be a spot or two that I could use to offset the usual weight gain.


> be ware of flutter bothe extended span and redistribution of weight
> beafing up the spar/web.

Your point about the flutter is well taken -- especially from the extended wing prospective. Beefing up the spar and web should increase the stiffness, which would raise the resonant frequency. I wouldn't be concerned with that as much as lengthening the wing.
>
> in extending span from tip out wards..,beware of tip stall as the wing
> reduces in size as you go out,it is also posible any smaller cord size may
> not actully be benificial.also it will be dificult to get wing area as your
> wing tapers to a vanishing point.

This is an area I don't even claim to know much about. Anyone have some thoughts on winglets?
>
> cliping the wings gives you less load on the root.. or cliping and adding to
> the root,giving if done right les load on the root and your desired wing
> load. may be worth talking to an arodynamist and aronautical engeneer about
> for your desire out come.
> but dont forget to shift the mixer and push rods,change the lenghth of the
> tork arm,cables and also lenthen the back of the fuse to house it all becaus
> your flaps/elerons are now futher back.

I'm not as worried about the wing root load so much, I really don't think that's a big issue with the strength of the carbon pultrusions. You don't add much weight and the are very strong-- I can run the numbers when it comes down to it (assuming that it's feasible to do for a heavier pilot).

> dont forget to take into account water,reserve,verio,gps,phone,lots of
> clothes and the balast you will need in the tail.

Could some of those weight and balance issues be offset by scalling the entire aircraft just a bit, say 3-5% while keeping the cockpit length close to the original. If you cuold do that the impact of the extra weight forward of the lft center could be just a bit less. How much ballast is usually needed, or is that just the case when the pilot is heavy?
>
> do you fit in a dragon cockpit?

I don't know the answer to that question -- there aren't so many of them out there to get into. I'm just under 5'10" tall, and not really big built.
>

Otherwise, what is the consequence to performance, excluding strength, for the pilot being heavy? Increased stall speed, increased sink-rate? Anything else?

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