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81" vs 118" essential differences?

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81" vs 118" essential differences?

Old 06-18-2006, 12:51 PM
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flaphoto
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Default 81" vs 118" essential differences?

I'm a total novice to gliders. What is the essential difference between gliders of similar design that are just different wingspans? Say 81" and 118" with electric motors?

Does one thermal better than other, wind handling, aerobatics?

Old 06-18-2006, 01:17 PM
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Liberator
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Default RE: 81" vs 118" essential differences?

I am sure that I will have people disagree, but to me the larger plane is much easier to thermal and have longer flights more days than not. That is not to say that you can't stay up as long with the smaller wingspan, on the right day it feels like a brick will thermal. I guess the best way to put it is I have had longer flight with my 115" Bird of Time, than I have ever had with any of my two meter planes. It just seems that I find lift better and more consitantly with the larger span planes.

The 2 meter stuff tends to be more forgiving in tighter fields, they also do not require as strong a launch to acheive the same altitude.

Sorry I just saw the electric motor part of your question. With the assist of the electric motor you are able to get to the altitude where thermals are a little more forgiving. Down low they tend to make you work harder for them than up higher.

Having said all of that... I only fly gliders with no electric assist. I am sure that someone will have some experience with those to ad to my ramblings.

Welcome and have fun!

Old 06-18-2006, 03:30 PM
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flaphoto
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Default RE: 81" vs 118" essential differences?

in the helo world, many find the bigger birds easier to fly as they tend to be steadier, less gittery. I would think some of the size thing might translate to the glider world also. I kind of prefer to see the bigger birds doing bigger, slower aero...downloaded one from one of the links and the 3 meter bird looked great doing the slow, graceful rolls. Got to be easer to see also.
I am aiming at the electric because I don't want to monkey with the launch systems...not yet anyway. I am really looking forward to what appears to be a much more relaxing hobby, something I can do with my son.
Old 06-18-2006, 06:58 PM
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Default RE: 81" vs 118" essential differences?

The bigger models will fly better as far as duration and sink rate is concerned. Speed comes from the design more than the size but a larger model will be more effiient and could well show a wider speed range for other wise similar designs.
Old 06-18-2006, 07:39 PM
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flaphoto
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Default RE: 81" vs 118" essential differences?

sounds like 3M birds are what I'm interested then. Thermik, Stork E, Baracuda are all 118" birds. Prices vary fairly dramatically, $400, $550, $280 respectively. Difficult to make a decision without finding a club, so time to do some more forum reading.
Old 06-19-2006, 12:23 PM
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Default RE: 81" vs 118" essential differences?

For comparison sake, I have a Spirit 2m and Spirit 100 and I can tell you for a fact that the 100 has a lower sink rate and better glide ratio. The 100 is bigger and needs more tension to get it up though.

With an electric motor, field size is not much of an issue if you have a good glide path control device. Good spoilers, flaps or crow are essential for landing big machines in tight areas safely.


Scot
Old 06-19-2006, 01:56 PM
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Default RE: 81" vs 118" essential differences?

Flaphoto:

I have a Siren (medium liner)(78" ) and had an Ellipsoid II (110" ), and now a 4m Discus.

The siren has a much quicker up/down time than the Ellispoid did.

Although both would climb at the same rate (2500+ ft/minute).
The Ellipsoid was under 5 seconds to 400 ft, and the Siren is about 5 seconds to 400ft.

on a 5 second jump to 400ft, the siren would take about 6-8 minutes to come down without using the motor to power up again, and the Ellipsoid about 10-12 minutes.

I fly in Phoenix, so I have a good chance of catching thermals after 8:00am in the summer.(when the temps are still below 110)

Personally speaking, I like the bigger winged aircraft. It is much more relaxing, and when you do hit a thermal, you typically won't blow right through it like you would on a hot/medium liner. Also, all that wing area helps.

Spoilers/ Spoilerons/Flaperons:
I only have flaperons on the Siren, and they do slow the plane down quite a bit when engaged.

My 4m Discus has Airbrakes/Spoilers and I have yet to findout how they work, as we have yet to fly her.

Good luck in your decision, and welcome to the Fun of Gliders.

Dave
Old 06-19-2006, 02:46 PM
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n0irw
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Default RE: 81" vs 118" essential differences?

A very wise glider guider told me when I first got started in sailplanes almost 20 years ago and I have found it to be very sound advice....

"There is no substitute for wingspan"

Kevin O'Dell
Old 06-19-2006, 06:13 PM
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flaphoto
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Default RE: 81" vs 118" essential differences?

appreciate sharing your advice. Rotorspan is similar to wingspan in the helo world (at least for aerial photography...helos don't thermal very well as far as I know)
I can't wait to get started. I've never flown anything that is truely relaxing...and I've been flying helos for 20 years...satisfying, not relaxing.

Looking at a few models, Thermik Dream sold out for next 6-8 weeks from Espirt. Checking on Stork E, Baracuda, XL 3200. All 118" or more. I think I am going to go with a Hacker motor and LiPos. Still researching servos and ESC and receiver. I have preference for JR stuff just because I am familiar with it. Guess what I really need to do is find a local club to get some advice.

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