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3 or 4 engines

I was talking about my Nosen Trainer in another thread, and it got me to thinking again about building a plane with 3 or 4 engines. I had a Telemaster a few years back with a Saito 65, which could be removed and replaced with an OS 20 FP. I built two engine nacelles that went on the wings to make it a triple 20 FP airplane, and the best part was that I could switch back and forth in about 15 minutes. It flew very well and the power from either configuration was about the same and was perfect for the plane.

My Nosen Trainer had a similar arrangement. It had a 91 Surpass in the nose, and a cover plate that would cover the hole in the cowl when the engine was removed. I built four nacelles with OS 26 four-strokes that were linked together with some very nifty throttle linkage. The nacelles were balanced so that changing engines would not affect the center of gravity, and they had overlapping propellers that looked very cool. The sound of all four engines was incredible. I'd like to build another plane with a this engine configuration. Here are some photos that I took back in the good old days when digital cameras took really crappy pictures:

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The only problem is that either configuration was just too much engine for that plane. I wanted a plane that was light and easy to handle, but the Nosen Trainer was too much of that. With the four engines running, it would taxi at almost take-off speed, and it didn't want to land at all. I ended up selling it to keep from wrecking it.

I've been thinking that I need to build another plane with four engines, preferably OS 26 four stroke because I still have all four of those engines. I want something with a bit more drag. I was thinking about scaling up a set of Great Planes Big Stik 60 plans because of its thick symmetrical airfol. Any other ideas? I'm almost finished with a Lazy Ace, and now I'm thinking that it would have been perfect for four OS

26s, but that probably would look funny and it would be way too much building for one plane. It already has wire struts and two sets of wings....

The reason I made the nacelles so low on the Nosen was to get the ailerons out of the prop wash. This was a bit of an issue with the Telemaster, which had the nacelles right on the bottom of the wings. So a Big Stik may present a problem because of low ground clearance. Maybe a Big Stik with the cabin stretched upwards to look like a high-winger? Anybody else ever take on a project like this? I have a lot of raw balsa wood to use, and I don't want to modify an existing airplane. Any ideas?

Reply to
Robbie and Laura Reynolds
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B17. B29. B24. Lancaster. There were some nifty tween-war biplane transports, the names of which escape me (but not the number of struts

-- a way-stand-off-scale WWII bomber or post-war airliner would be much easier). Sikorsky built a 4-engine bomber for white Russia before they fell to the commies in WWI.

etc.

Reply to
Tim Wescott

Why didn't I think of that? I have never built war planes. Maybe I should look more closely at the WWI biplane bombers. There were some really nifty ones. Do any come to mind that had four engines?

Reply to
Robbie and Laura Reynolds

I think that reversing the props of a couple, or all four engines would have permitted it to run in the rpm range it needed and sound as good, yet it would have developed less thrust.

Ken, general lurker.

Reply to
Ken Cashion

Ken Cashion wrote:ng it to keep from wrecking it.

That's a great idea. I wish I had thought of that. I'll have to keep that in mind.

I've been looking for photos of early 4-engine planes online because my Jane's encyclopedia is packed in a box. We thought we were going to be selling our house and moving last year, but it hasn't happened yet...

I found a photo of the Junkers G 38 4-engine transport. That's a pretty cool plane.

Reply to
Robbie and Laura Reynolds

Here's one by Igor Sikorsky before he emigrated to the USA:

That thing must have had a LOT of drag!

Reply to
Geoff Sanders

WOW! That's a cool plane. I might have to build one of those.

Reply to
Robbie and Laura Reynolds

I found a review of a static kit of this plane:

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Reply to
Robbie and Laura Reynolds

If you DO build one, it's fer sure it WON'T be nose heavy! ;-)

Reply to
Geoff Sanders

I was just thinking the same thing. Pre WWII airplanes always stir the most excitement in me. I love looking at biplanes, and these big four-engine monsters are some of the greatest pieces of work in history. However, once the initial excitement wears off and I start thinking about cutting balsa, the weight and balance issue always comes up. There's a plane in the RCM catalog called the Doppledecker. It's a

10 size biplane designed by Fred Reese to look like a WWI biplane, but it's not a scale model of anything. Maybe that's the best approach. If I make something that looks like an old Caproni or Gotha without actually being one, it would be just as much fun for me. I could also avoid all of those pusher props that way.
Reply to
Robbie and Laura Reynolds

That was my thinking with a little electric I built earlier this year. I saw a free plan in Fly RC last year by Thayer Sime that was billed as a "coulda-shoulda been" 1930s racer. I didn't think it looked like a typical racer of that period, so I designed my own. It's not a scale model of anything, but it looks as if it is. Flies well too! :-)

Reply to
Geoff Sanders

Reply to
Paul Ryan

Thanks, but it was a bit more simple than that. The engine pylons were removable. They were joined in pairs at the top by a piece of hard plywood, held to the bottom of the wings by nylon bolts. This plane had only one set of wings. The part that I was most proud of was the linkage to couple the pairs of throttles, and the fact that taking them off and putting the 91 on didn't change the CG.

Do you have a set of plans for the Christen Eagle? Or are you designing the wings yourself?

Reply to
Robbie and Laura Reynolds

I modified a Kadet Sr. with two TT36's on it. Also added flaps, ailerons and modified the outline a bit. Can send a pic if you are interested. Flew incredibly well. I think that 4 20s would be amazing.

Gord Sch> I was talking about my Nosen Trainer in another thread, and it got me to

Reply to
gords

You got me thinking. If you want British, look up

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and
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You could also consider a Ford Tri-motor

-- for that matter, the tri-motor layout seemed to be popular in the mid to late 30's, so there are numerous non-Ford examples to be had.

Reply to
Tim Wescott

I just wish my Jane's encyclopedia wasn't buried under a pile of boxes...

I love the old monster biplanes with forests of struts, although I wouldn't want to build all of that bracing on a model. The Ford and Junkers trimotor planes score very high on the cool scale. There was a Junkers construction article in RCM about 15 years ago. If I remember correctly, the designer used K&B 20 Sportsters. That one would be great with OS 26s instead. I ALMOST ordered the plans when I read the article.

Can you still get RCM plans? I've been away from RC for about a year and a half. I heard that RCM went down the tubes, but I also heard that the plans were still available. I don't know if I should send money and trust that I will get plans in the mail.

Reply to
Robbie and Laura Reynolds

I'd love to see your photos. I am curious about your nacelle construction. Did you make it convertible to single engine configuration, or was it twin only?

I have the RCM plans for the original Twinstar, which was of course originally called the Twinstar 15 for the recommended size of each engine. I have seen the ARF version fly with twin OS 40 LA engines instead, which seems ridiculous to me. These planes can be a handful with that much power. I like the idea of something big, slow, and draggy with lots of lift. The Kadet seems like a great choice. The Ford Trimotor is sounding better and better the more I think about it. There was a really old Trimotor plan in RCM from the 1960s that used one

60 in the nose and 049s in the wings just for show. This was most likely because the original plane had tiny nacelles behind huge radial engines. I would rather fly with three OS 26es instead, but it would be hard to work out the nacelles. Didn't the Junkers trimotor have more reasonable nacelles?
Reply to
Robbie and Laura Reynolds

How about the Vickers Vimy bomber? It only had two engines, but they were big ones!

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There was a replica built that had V-8 engines in it, a few years ago. It flew to OSH, and was quite impressive. It is huge!

Reply to
Morgans

If you wnt a tri-motor that NOBODY else has, go French!

You might want to add a bit of vertical stabilizer, though!

Reply to
Geoff Sanders

That's a cool plane. There's something decidedly French-looking about the styling...

If I were more of a scale builder I would be thinking very seriously about this design. For now, I think I figured out what I want to build, as soon as I get my Lazy Ace finished. I have a couple of Cloud Dancers that I framed up from the 40 size RCM plans. All I have so far is the individual wing sections and fuselage sides. I think I'll do one of them with three OS 15s. Depending on how well I like that, I'll probably do the other one with two 20s or 25s.

Reply to
Robbie and Laura Reynolds

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