High aspect ratio sailplane

[macboffin]

Now this would make a super scale model ; but how to build that wing?

[PeteSchug]

Now this would make a super scale model ; but how to build that wing?

There has been a series of articles in Quiet Flier on how molded wings and fuses are made. I would dig up the back issues and read them, then decide if I really wanted a wing that badly.

It's a monster of a job but once you've made one you can make more with a lot less effort. It is still work though, and you are not done until the top and bottom are joined successfully.

This is something I prefer to buy. The Czechs seem to be very good at making molded wings on models. It's not that I am too old to learn, but that I might never get to the final stages.

I've heard that some of the early full-sized glass ships had flutter problems and full scale gliders tend to have over built wings (as far as G loading goes) just to make them stiff enough and less flexible. I would guess the same thing goes for models, but I don't know what overbuilt amounts to. Another reason to buy from someone more experienced.

I have most of the back issues but I never read the articles since I gave up making glass planes WAY back.

Oops edit: Reynolds numbers rear their not to friendly head when you look at projects like this. Not only do you have to build a huge wing, but you also have to make sure that the whole plane is big enough for the chord and airspeed to move into an acceptable Reynolds number range.

Pete

[s2000]

Macboffin, you have a fellow Englander here in California that has already done one of these, very nice at 1/3 scale, go ahead and chime Tony!

[SoarScale2]

A red rag to a bull!!!

Yep, it is the Eta with an aspect ratio of about 53:1. I built a 10.3m 1:3 scale version of this a couple years back. The models L/D was very impressive with that aspect ratio - here are a few pictures of the model.

Tony Elliott

[SoarScale2]

Just for grins, this is the wing flex on take off. This aircraft took me about 4 months of significant number crunching and many design concepts to arrive at a torsionally stiff yet realistically flexible and light-weight wing design WITHOUT the use of fully molded technology.

The net weight of the ship was about 38lbs.

If you are real interested in the aircraft flying, RadioCarbonArt did a feature on this plane and added the feature to the ProAerotow DVD that I believe is available from a supplier in the UK. It is advertised in the the QEFI magazine published in the UK. The feature is an interview with me as well as flight footage including two 5 to 7 G loops I performed for the camera.

One of the best performing aircraft I have built to date.

Tony

[infopimp]

Tony, that is seriously impressive. Unbelievable in a way. Nice work!

[PeteSchug]

The only thing I can think of is... WOW

Pete

[zero-zero]

Tony, I have seen your ETA in Paul Naton's DVDs and, although I do not care for extreme aspect ratio wings, I did find it impressive. Your use of the past tense worries me. Is the Eta no more? I hope not.

[Paul Naton]

Tony's Eta is the most impressive scale plane I have seen to date, and I have seen a lot of big planes fly. The footage and interview with Tony is featured on the Pro Aero Tow and Just Want To Fly DVDs. Both films are available from www.radiocarbonart.com or from Traplet.

This planes thermaling performance is outstanding. The footage on the DVDs was shot at Los Banos in some good mid day conditions. Tony popped the spoilers, gear, and flaps, and tried to circle down, but said "this thing won't come down!"

I think the full scale Eta/Open Class production was halted after some structural problems were found. The Eta has entered some competitons and performed well though not a world beater.

Paul Naton

[SoarScale2]

zero-zero - past tense is true but the Eta is fine, I just don't own it any more. I sold the aircraft to a guy in Florida. The person that bought it "collects" large scale sailplanes and from what I know, it hasen't flown since I sold it over 18 months ago. My belief is that it is still in its crate in a hangar.

There are times when I regret selling it because it is a superb aircraft to fly and is certainly a draw for the crowd. I simply did not have the room to store it anymore. This and the SB-10 were very large aircraft with crates on the order of 14 to 16 feet long.

I also sold my 10.6m SB-10 to the same person. While I do believe that the SB-10 has been out of its crate for show purposes, I don't believe this one has flown either.

Sometimes you have just got to make room for new aircraft!! My latest project is a 1:3 scale 9m ASW22 scratch build that will maiden later this month in Visalia, CA.

Paul, thanks for the post. I wasn't aware you had added it to the "Just want to fly" DVD - way cool!!