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#1 jbrandon Apr 20, 2006 12:19 PM

LJMP Meteor
 
3 Attachment(s)
Just finished the LJMP Meteor from the 80s. The build is a scratch build as I have only found one kit and he would not part with it.

Link to my build photo build (build log).


Wingspan (20oz each) is 127, root cord is 8 5/8 and the tip cord is 6 1/2

Fuselage (48oz) is 53

Stabilizer (3.2oz) is 30, root cord is 5 1/2" and the tip cord is 3 1/2"

Fin is 12 tall

Flying weigh will be 91 oz. This is quite a bit heaver than I wanted. This is probably due to my inexperience with fiberglass and I am sure I got too much resin on the fin and aft boom. Some carbon was used, the spars are capped top and bottom with .014 carbon and wrapped with carbon tow, the wing trailing edge is built up with .007 carbon, the stabilizer has .007 carbon in leading and trailing edge, the rudder has .007 carbon on the trailing edge.

#2 jfrickie Apr 20, 2006 06:05 PM

Bring it out to the sodfarm Saturday and test fly it. Ill have a winch set up.

#3 jbrandon Apr 20, 2006 06:28 PM

Thanks Jim, Ill have to see how thing go around here tomorrow. But if things are looking okay tomorrow evening then I may come out. I did hand toss it this afternoon and wiggled its tail!

What time? You know I have to pack a bag to get that far south!

#4 MrKie Apr 20, 2006 07:43 PM

If the mail comes in time you will have a new super chute to test along with a great looking new plane May the air aways be good Mr. Kite

#5 jfrickie Apr 20, 2006 08:15 PM

Jim,check out the club forum, I have all the info there. Hope you can make it. I always like to see a new planes first flights!!

#6 jbrandon Apr 21, 2006 08:27 AM

MrKie: I am hoping they show up this week. The one I have is in tatters and is really unusable. I purchased two new chutes but have put them away and now cant find them!

jfrickie: I will not be able to get out this weekend. Just heard from a relative and they are coming in for the weekend. Alas, no flying for me! BTW, I gave up on finding a turnaround and made one, yes, the old bicycle hub thing but it will work for my type of flying.

#7 jfrickie Apr 21, 2006 07:25 PM

No problem. I found some issues with my tow plane and fixed them,so I am going to test fly it tomorrow at the sod farm and set the winch up on Sunday. I want to make sure I don't have any problems with it next weekend at the aerotow. I did fly my Sharon pro all afternoon today. Unbelievable lift. Got it sorted out and should make a good back up for the Masters. Jim

#8 sailplaner May 15, 2006 09:04 PM

Mr. Frickie,

Do you (by chance) have a copy of the plans? I would be willing to negotiate the donation of a limb for a copy. If body parts are not enough I would gladly pay duplication and shipping costs.

If you have any interest in the LJMP Pantera, I can get a copy of it for you in trade?

I'm interested in how well your carbon reinforcement helps prevent wing flutter? The scariest thing I think I ever saw was the long slender wings of a Meteor start to flutter when coming in a little too quickly to make the landing time.

Regards,
Mark

#9 jfrickie May 15, 2006 09:23 PM

I think you mean JBrandon.

#10 sailplaner May 15, 2006 09:33 PM

Yes, thanks. I see my error. I was in such a titter about the plans I addressed to the incorrect poster.

As it turns out, Jim and I just missed each other "way back when" flying with mutual friends.

Thanks.
Mark

#11 jbrandon May 16, 2006 12:59 PM

1 Attachment(s)
Sailplaner: I have built quite a few Meteors and the only one I saw any wing flutter with was John Browns and as I remember his was the prototype and had only a single spar. The plans call for a main spar of 3/8x1/8 spruce and a second one of 1/4x1/8. The plans say to use 3/8 vertical grained sheer web between the spruce on the main panel but the aft spar is only webbed with 1/16 on the rear. But I never built that way. I always used 1/2x1/8 or like this one 1/2x3/16 spruce (and I mean quarter sawn spruce, not basswood) and used a second spar at about 60% of 3/8x1/8 spruce. The spoilers were located behind the second spar not the main spar like the plans show. The first 24 of the spar is sheer webbed with 1/6 plywood forward and 12 plywood aft. The entire spar is sheer webbed with 1/2 vertical grained balsa between the spruce and also on front and back with 1/16 balsa. This is also done on the tips stopping 3 bays from the tip. I also sheeted out 12 from the root and to the rear spar both top and bottom and I think that really stiffens the wing. This one has .014 carbon top and bottom of the spar (and I really dont think it was needed) and is wrapped with carbon tow for the entire length of the plywood. Back in the 80s I had a couple of joiner boxes separate under stress and started using fishing line, something like 100 pound test but the tow is far better, stronger and easier to work with. The spar was constructed totally independent of the wing itself. The tips are built with about 1/8 of washout into the panel because I could never get it to warp in with the covering and hold.

I really believe in this D tube-box type of construction and if I am looking for strength I use it, heck, I use it just about in all my building, I just scale the parts down to fit what I am building. There is a little bit of weight penalty but most of it is at CG. My wings still wiggle in the lightest of lift. But the only flex is during launch and that is the wing rod and Ive never seen or heard any flutter. The wing joiner is a 3/8" ejector pin and although it does flex it is nothing like the old rods we used in the 80s.

I actually built one extra main panel (by mistake, dont ask, dont tell) and I destroyed it testing to see just how strong it was. I can only measure up to about 90 pounds and it took far more than that to break the panel and then it only cracked and buckled the top sheeting at, I am guessing about 150 pounds. I was not able to break the spar until I took it and put one end in vise and pulled on the end of the panel. It broke just where the forward plywood sheer web stopped. Figured it would break there if anywhere. But even then it did not shatter, but splintered and I think the plane would have been somewhat flyable. I should have made a video! It was neat.

One of the things I always liked about the Meteor was when you went fast the wings would flatten somewhat due to joiner rod flex and it really look cool flying across the sky, but alas, this one doesnt do that!

Just for fun, here is the original John Brown Meteor front center.

Okay, enough of this stuff, back to fixing my web server!

#12 s2000 May 16, 2006 02:33 PM

All I can say is "Oh My God", this picture goes back aways. I am at the back, far right in the photo, holding a red built up aileron ship of my own design. This makes me want to build another Meteor. And I am pretty sure I know where a stash of fuselages are located, maybe even wing ribs and plans. I used to cut and sand the parts for the kits. Larry will get a laugh when he sees this photo! And nice job on the Meteor Jim!

#13 thermalbum May 16, 2006 04:00 PM

"And I am pretty sure I know where a stash of fuselages are located"

If there is any and if they are for sale I would like to buy one. The Meteor was the best poly-ship I ever owned and it could/would regularly beat the flat winged wonders during the mid 90s.

#14 jbrandon May 16, 2006 08:42 PM

s2000: Thanks for the complement. It is a fun airplane! Larry has seen the picture. Now who are you, I think I know and Ill PM you to find out for sure but I think you initials are DB! Ive also built an Electricus and it is a rocket!

thermalbum: Yes there are supposedly some in Larrys shop. Id like to have one as mine came out a little heavy but still flies great.

I have finally got my web server repaired and the site is back up.

#15 s2000 May 17, 2006 11:36 AM

Good guess Jim, yes it's Dennis, S2000 is my weekend fun on 4 wheels.


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