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Weight lifting competitions. - 2/11/2003 6:02:09 PM   
AR196


 

Posts: 185
Joined: 1/2/2003
From: Newmarket, ON, CANADA
Status: offline 		There was a web site called world's ugliest airplane survey. There were rivals for that air car bipe.

I believe it was on that site to that I found a jet powered biplane. Don't remember if it had tricycle gear. It was definitley a contender for ugliness with the air car. Will see if I can find it.

(in reply to Zweihander)
       Post #: 26

Weight lifting competitions. - 2/11/2003 7:08:20 PM   
AR196


 

Posts: 185
Joined: 1/2/2003
From: Newmarket, ON, CANADA
Status: offline 		Oaky, guys, check it out!!

This one's got it all - tricylce bipe, twin boom tail, jet powered - so that makes it a pusher too.

Oh, yeh, take another look - it's also retractable!!!

WoW!! Ugly, too.

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       Post #: 27

Ugliest Bipe - 2/11/2003 10:23:47 PM   
flicka5



Posts: 634
Joined: 3/1/2002
From: Jamestown, NY, USA
Status: offline 		AR196, what are those two massive globs of aircraft structure between the wings? Tanks for crop dusting/spraying at a very rapid rate/jet speeds?

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       Post #: 28

Weight lifting competitions. - 2/11/2003 11:29:54 PM   
Ralph Morris



Posts: 192
Joined: 11/29/2002
From: Glendale, AZ, USA
Status: offline 		AR196; Ugly is in the eye of the beholder, you know. That's not the ugliest jet-powered biplane I've ever seen, but of course it's the ONLY jet-powered biplane I've ever seen!

Do you know what the blobs at the front of the booms are for? Flicka5 guessed they were for aerial spraying. Maybe it's a secret CIA sprayer for eradicating cocaine and marijuana crops in Columbia. They would need jet speed to avoid ground fire.

The vegatation in the photo looks sub-tropical. Do you know any more about this unusual aircraft?


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Keep 'em flying!

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       Post #: 29

Weight lifting competitions. - 2/11/2003 11:42:51 PM   
AR196


 

Posts: 185
Joined: 1/2/2003
From: Newmarket, ON, CANADA
Status: offline 		Unfortunately, I know no more about that plane.

Seems I recall that it was of Eastern Block origin. Something looks Antonov about it to me, although I'm certain that's not the manufacturer.

The site where I found it is no longer up. I'll check my notes from way back and see if I made a reference. Chances are slim but I'll check.

Can't quite make out the registration on the lower upper wing surface.

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       Post #: 30

Weight lifting competitions. - 2/11/2003 11:55:26 PM   
AR196


 

Posts: 185
Joined: 1/2/2003
From: Newmarket, ON, CANADA
Status: offline 		Okay. Here's the scoop. Flicka is RIGHT!!

It's a crop duster!!!

Checked my notes and wow, did I save a stack of stuff on this one.

Made by PZL, the guys who do the Wilga, as a replacement for the Antonov AN2 Colt - another cool bipe.

Here's a link to a site with a description: http://www.luftfahrtmuseum.com/htmi/itf/pzl15.htm

If that's not enough and you can read Polish, try a search for PZL M15 on Google. The first link is to a Polish site describing the plane.

Amazing, Flicka, you got it right on the first try!!

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       Post #: 31

Tricycle biplane, or bicycle triplane? - 2/12/2003 12:06:15 AM   
Ralph Morris



Posts: 192
Joined: 11/29/2002
From: Glendale, AZ, USA
Status: offline 		[QUOTE]Originally posted by Zweihander
I originally designed a tandem wing plane, but quickly realized that someone has to fly it, which I have never seen anybody try. Bipe seemed close enough to me.

I will definately post pictures of the plane once complete after the competition. [/QUOTE]

Don't be afraid of a tandem-wing design. There are several successful ones, full-scale and models. Make a smaller model, with a box fuselage so you can move the forward wing fore and aft. Place the CG (cargo hold) just ahead of the aft wing, and vary the size and location of the front wing to achieve balance and positive pitch stability.

You can calculate the wing areas and distance from CG to centers of aerodynamic effort using standard equations or a simple graphic method.

By the way, you don't need a horizontal stabilizer for this design, although Andy Lennon put a T-tail on a similar one. This is the only photo I could find, but you can see the general layout. Notice how close to the ground the front wing is, in order for it to produce more lift than the aft wing, when lifting off. It's a natural for a weight-lifting contest.

http://www.amazon.com/exec/obidos/tg/detail/-/0911295402/ref=lib_rd_prev_4/104-9375038-2675145?v=glance&s=books&vi=reader&img=4&jumbo=1#reader-link

I've completed a design for a canard without verticals, except for the pylon that supports the aft wing. It banks and turns ala B-2, using "spoilerons," and is designed to compete in the annual R/C Marathon held at Baker, California. The open class allows 1/2 gallon of fuel of your choice, and the longest distance flown over a 50-mile closed course wins. You have to follow the airplane down a two-lane blacktop with a convertible or pickup, so you can see the airplane overhead. It's great fun, and the team I was on won the open event twice back in the 90s (Team LA-LA, sponsored by Jim Kelley). Click on the following link to check it out. It's similar to weight lifting, when you consider lifting off with 1/2 gallon of fuel aboard. They now have an electric class, as well as open and sportsman, where you can fly your regular Sunday flyer.

http://www.camarathon.com/


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Keep 'em flying!

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       Post #: 32

After the competition? - 2/12/2003 12:19:59 AM   
Ralph Morris



Posts: 192
Joined: 11/29/2002
From: Glendale, AZ, USA
Status: offline 		[QUOTE]Originally posted by Zweihander
I will definately post pictures of the plane once complete after the competition. [/QUOTE]

Tyler; Better photograph your airplane BEFORE the competition. Attempting to lift four or five times the aircraft's weight has been known to cause crashes!

Good luck in the competition!


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Keep 'em flying!

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       Post #: 33

Way off subject? - 2/12/2003 4:29:47 AM   
flicka5



Posts: 634
Joined: 3/1/2002
From: Jamestown, NY, USA
Status: offline 		Since the Russian bipe, the AN2 was mentioned by AR196, I just have to tell this story, quickly!

Went to a large scale model rally several years ago at a private grass strip, full size airport. The main runway and I guess the only runway was maybe 40 ft. wide, max.. Sometime during the day, the sponsor club had arranged for a somewhat local AN2 Colt to fly in and park for a "look at" by the modelers and spectators. The sponsoring model club had wooden stakes maybe 2 in. sq. pounded in the ground creating a straight line with rope between the pits and the flight line to keep spectators from getting too close to the flying models. So everyone quit flying at one point to allow the AN2 to land in front of our model flight line. Well the lower wing of the AN2 is not very far off the ground and also quite large span-wise. It landed right in front of us very, very slowly and started tearing up the stakes one by one as the lower wing drove through them.

I went over to the parked Colt sometime later and the owner/pilot told me that the Colt had just been recovered and painted! It had a lot of duck tape patches over the bottom of the wing covering; the duck tape having been supplied by the airport owner to cover up the holes created a few hours before! The good news was that owner did not believe that he had any structural damage to the wing. Could not believe how slow those Russian bipes can fly. They almost appear to stop in midair at the slowest speed.
Real bummer!

< Message edited by flicka5 -- Feb 12 2003 2:13AM >

(in reply to Zweihander)
       Post #: 34

Weight lifting competitions. - 2/12/2003 6:57:53 AM   
AR196


 

Posts: 185
Joined: 1/2/2003
From: Newmarket, ON, CANADA
Status: offline 		Ralph,

I agree, beauty IS in the eye of the beholder.

However, sometimes, in all beholders' eyes there is no beauty.

So, we now have the other bipe that it was suggested should have the interplane struts at the wing tips, which in this case are plates, to provide more lift. At least it's got a round engine and a tailwheel.

Some guys think of everything!

Behold:

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Weight lifting competitions. - 2/12/2003 7:31:09 AM   
Ben Lanterman



Posts: 1284
Joined: 10/27/2002
From: St. Charles, MO, USA
Status: offline 		Ralph, The competition sounds interesting but I don't understand why you don't want to use verticals. Granted weight equates to loss of performance but they are mostly weightless and do a good job of keeping the pointy end of the nose going in the right direction.

Spoilerons are Ok for directional control if you don't have a rudder but if the airplane is statically directionally unstable then it would need an autopilot to drive the spoilerons. Spoilerons are also drag producing, perhaps more so than the verticals. If the model has any wandering of the fuselage from straight ahead it can end up being draggy at the end of a long competition.

I imagine you are going to check out the configuration with a small model to verify. I would be interested in seeing a picture of the final design. There are many ways to skin a cat but some of them are unpleasant and messy.

As far as weight lifting goes I have to assume that the guys that have flown the competitions before have performed the tradeoff evaluations. I notice that they all tend to put their area into one lifting surface. So do the big cargo carriers in the full scale world.

The problem with a tandem wing is that although the front wing can operate in the ground effect the second wing sees a highly variable downwash from the front wing. Even with the aft wing set high it is effected by the downwash and can produce some nonlinear results.


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Ben Lanterman

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Weight lifting competitions. - 2/12/2003 3:02:11 PM   
Daniel Nelson


 

Posts: 87
Joined: 11/20/2002
From: Lancaster, CA,
Status: offline 		Ben- a couple of notes.

Stability augmentation systems are (I believe) not allowed, so gyros and copilots are out. Thankfully, the span limit really makes things easier on our pilot; he says the plane acts like an underpowered trainer.

In the past years, with no span limit and a max planform it made sense to get aspect ratio is high as possible, but that's out the window this year. I'll bet there'll be a lot of biplanes at the competition, but I still think a monoplane using a very high lift airfoil will win.

We oughta get a thread going for people who want to talk about the SAE aerodesign competition.

(in reply to Zweihander)
       Post #: 37

Bipe on Steriods - 2/12/2003 11:39:35 PM   
Ralph Morris



Posts: 192
Joined: 11/29/2002
From: Glendale, AZ, USA
Status: offline 		AR196; That is a beauty. However, I hope they don't test for steroids in that competition. I love those tipplets! Ugly, but functional.

Ben; Thanks for your thoughtful comments on my long-distance design.

Where would you put a vertical stabilizer on a canard-pusher? The wing is located at the tail end, and the fuselage is a long tube supporting the canard. The 1/2-gallon fuel tank is located at the leading edge of the wing.

One of my preliminary designs shows a rudder on short booms, operating a few inches aft of the propeller. Keep in mind that the pylon supporting the wing is a vertical section of about 35 sq in., so I shouldn't say it has no verticals. However, It has no winglets or tipplets.

You can place a horizontal stabilizer either aft of the wing, or forward, where it's called a canard (French word for "duck" .

A vertical stabilizer, on the other hand, works better positioned aft of the wing. Perhaps Ben will explain why, in aerodynamic terms. The difference is gravity.

[QUOTE]Originally posted by Daniel Nelson

We oughta get a thread going for people who want to talk about the SAE aerodesign competition. [/QUOTE]

Dan; Maybe we could petition the moderator to change the title of this thread to "SAE Weight-lifting Contest," with Tyler's permission, of course.


_____________________________

Keep 'em flying!

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       Post #: 38

Weight lifting competitions. - 2/13/2003 5:58:10 AM   
Ben Lanterman



Posts: 1284
Joined: 10/27/2002
From: St. Charles, MO, USA
Status: offline 		The most obvious would be dual booms with a stabilizer/rudder on each boom set far enough out so that you don't whack them when starting the motor (actually that's something I would do. Like picking up the fuselage and ramming the tail through the ceiling of the shop). There is something flying full scale called the Proteus

http://www.scaled.com/

has a picture. They also have a ARES and Voyager. It would be reasonable to copy them as they probably have found out that they need the directonal stability when using the canard layout. The canard is great for efficiency and is good enough to warrant sticking the verticals on the back.

If you put a shroud around the motor and prop and had it set several inches from the trailing edge it might also work as a vertical stab.


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Ben Lanterman

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       Post #: 39