Suo

Ive been thinkin of building a twinstar with a set of O.S. 40 LA motors vs the O.S. 25 Fx motors and get the bonus .4hp together. I figure Id mate it to a 9x7 prop to keep the rpms down.

If I sound like a nub its because I am. Ive never owned an RC plane but I have realflight G3. Dont blast me yet, Im also a Commercial/Multi/IFR Pilot, I know it doesnt mean squat.

Anyway if I crash because its to fast o well n my skill are noobish im fine with that. I took the twinstar in realflight and added the 0.S. .40 Fx with a 9x7props and if u keep the rpm with in 17,000rpm (factory Redline) it will easly hit over 100 mph. That motor makes 1.36hp vs the .40 LA's 1 hp so with 9x7 running WOT shouldnt overspeed the motor. As for the airframe I have no idea what the never exceed speed would be.

SIMCO

My Feedback: (33)

Real world vs. computer. It might be close. Too bad you will run out fuel in 3 minutes. One off sized tanks with no retrofit. 32's are fun on this plane and covers alot of real estate. Still won't out run a hot duellist 2 cents

Flight Risk

My Feedback: (1)

These planes are mighty speedy with .25 LA engines and still don't get long flights. 8-10 min. at mostly WOT. Also these planes need a lot of runway to slow down. Bigger, heavier engines will need a faster landing speed. You would almost need flaps or brakes. I know these are flown with .40's but there's really no need. If you get to much weight and speed you will also stress the wings. another 2 cents.

FR

iflyj3

My Feedback: (7)

Let us know when you fly this. I don't think you will need to worry about small tanks, they will last long enough for the first 15 second flight.

oldtyme

I am going to put .40 LA's on my twinstar. I don't think I will worry too much about overpowering this plane with that engine combo. I had an OS 46FX in a plane that I wanted to put in another plane so I removed it and put in a OS 46LA. There was such a significant drop in power that I quit flying that plane. While I think the LA's are good engines they definitely are not powerful. I also noticed a significant drop in fuel consumption between the FX and the LA so I don't think that will be a factor and 8-10 minute flights are long enough for me.........time to land and straighten out your neck.

Cheers,
Andy

Suo

Ok so ive done some more thinking.

Let me display my stats. (First I want to do all my shopping at towerhobbies)

(Second Im kinda stuck on OS engines and I have a very tight budget, id dont know much about other brands)

.25 ci^3 Engines

25FX .84 Hp @ 8.8 oz (10.47 oz per 1 hp) Price $ 84.99
25LA .6 Hp @ 6.9 oz (11.5 oz per 1 hp) Price $ 62.99

.36 ci^3 Engines
I cant seem to fine any of theses and the ones I have found are to expensive.

.40 ci^3 Engines

40FX 1.36 Hp @ 13.6 oz (10 oz per 1 hp) Price $ 109.99 (Too much)
40LA 1 hp @ 9.5 oz (9.5 oz per 1 hp) Price $ 59.99 ((Blue-63.99) Most powerful)

Ive learned that the plane will except any of these engines.

Im leaning too the 40LA but my consern is Speed vs Flight time. What engine will give me the best of both?

iflyj3

My Feedback: (7)

Suo,

While you are thinking, consider buying an LT 40 and using a OS 40 LA in it. Learn to fly it well and them buy another OS 40 LA and get the Twin Star.

Even though you may have mastered the sim, the actual flying is a little different. You don't need the problems with a twin when you are learning.

If you are on a limited budget and the way you are heading you will be gone from the hobby in less than two years.

Yes, I have a Twin Star with two 40 LA's and it is a fine plane. However, it is not the plane for a first timer.

Flight Risk

My Feedback: (1)

Actually my next project is to take a Sig LT 40 and put 2 LA 40's on it. I have the engines and plane waiting. That's how I stumbled on this thread, looking for twin conversions. So maybe an idea for you is to spend a while learning on a sigle engine, then buy another engine and do a conversion.
I'm sure that there is a 90% chance of crashing a low wing - twin engine while learning, even if you have mastered Real Flight. What ever you do, find an instructor to help you. As mentioned earlier you don't want to get frustrated and quit this great hobby.

FR

Suo

Ok i havent even mastered Realflight G3, I do understand the fact of flight instruction and learning on a simple single trainer.

The fact is I bought realflight so I wouldnt have to go threw a single engine and instruction because the fact is its very very expensive to buildup experence and knowlege. I dont even want to start a long term hobby. Im college student about to finish an AS degree in professional avation. Im sick and tired of flight training and dont plan to go onto becoming a CFI in fact the avation industry is just to much of a pain to get involved in. I like to fly Microsoft FS9 instead of flying the actauly plane. I have about over 200 hours(nothing) in Single engine complex aircraft and soon to get my hand on a twin(waste of money, need for degree)

I like working on thing and design things, making better and faster. I only plan to have this hobby for a short time while im in college or till I get myself a girlfirend. So this is just for a bit of fun. I want to slowly build this over a month and train hard in the simulator.

So iflyj3 you seem to have the same set up I want. What props do you uses, what is ur endurence, cruising speed and landing distance?

Thanks.

iflyj3

My Feedback: (7)

I use 3 blade 9X7 props. The total flight time would be about 8 minutes max and I only fly it about 6 minutes. Cruising speed etc, is not an important measurement in model aviation. I fly from a hard surface runway and it will land and stop in 300 feet by using a brake. On grass I have used a 400 foot runway with no problem.

Now, don't take this personally, but I think it needs to be said.

If your goals are as you have described, save your money and don't try model aviation.

You don't seem to have a commitment to any form of aviation.

Your spelling, grammar and punctuation are not at the level I would expect from a person about to get a degree.

I guess that was personal, but so be it.

SigFan

We have a guy at my field that had a twinstar with 2 40 la's. It flew fine, but he is an exceptional pilot (he taught me).

Suo

I dont check my spelling and grammer for a forum. You got my general point thats all that matters, speeling doont meter mutch. Thanks for the information I think im going to go for the twinstar with 40s. I like a challenge, for example my first car was a Honda with 90 lbs torque when I transferred to a rwd I didnt start off with a miata or V-6 mustang/camaro I went for the V-8 powered corvette with 350 lbs torque. Granted avation and cars have very different learning curves.

First Why would a low wing twin be harder to land?
Because of prop strikes?
Because ground effects?
Because of the clean design?
Maybe the CG of a twin makes the flaring sensitive?

Second why would the lack of ambition be a problem, I could understand the fact of a tight budget.


Just to inform you, Ive been an avation buff form the age of... well from the time I can remember. I loved it, but the Community college I went to and the flightschool are crap. I hit every pothole on the road to becoming a pilot(Its been a real nightmare and has almost killed my dream, and has placed me in a depression). If I had more money I get a single trainer and work my way up. Im a realy fast learner when it comes to driving things, books n school are difference ie why spelling and grammer arent so great. I soloed in 10 hours with no previous experence except for MSFS, I could of dun it under 10 hour except I had medical problems.

So here is my plan and I want to know if I should try it or just move-on. I want the twinstar with the .40 LAs. PERIOD. It will take me a month or two too build it as I cant afford the parts all a once. I will start a logbook(Self-management) of training flights in RF-G3, In the Simulator I run no gadgets so my eyes have to do the work. I will start will 0 cross wind and master take-off and landing in a pattern format. After that I will start to increase the cross wind by 2 or 3 mph, after each sucessful addition off cross wind I will slow turn the crosswind into a quarting tail wind. That should for the most part prepare my eyes and reactions for my first few flights. I will also practice single engine operations.

First flight: I will find an instructor and will do a few flights till im ready to solo.

Or should I just stick to realflight because im in for a big disapointment.

iflyj3

My Feedback: (7)

Suo,

I have no further comment. Good luck with your endeavors and goals.

Suo

lol

TCBLightning

My Feedback: (5)

Suo,

It's not recommended you start flying RC with a twin for the same reason you didn't start in a full-scale twin.

A Twinstar with LA 40s was my third plane after one year of flying R/C. I didn't have 200 hours in full-scale planes but have soloed in a Cessna 150 and been into aviation since I was able to pick my head up and look at airplanes flying overhead.

I didn't have the advantage of a simulator when learning, but having played with one (G2) for the past year and a half to keep me proficient during the winter months know that it is definitely not the same as the real thing.

My recommendation is to at least find a local club and get some stick time on a trainer. Have an experienced twin flyer help you out with the maiden voyage of your Twinstar and take it from there.

As for modifications to the fuel capacity I cut the top wing spar to make the fuel compartment bigger and put 6 oz. tanks in the nacelles. I added some bracing in the nacelle and that made it strong enough. I kept the LA 40s in there until I got sick of trying to get them syncrhonized then dumped 'em for a pair of 25 FXs. The power difference was noticable but not that significant from my perspective. The reliability of the FXs more than made up for the difference.

You have probably realized that your approach to this hobby is not very traditional. I don't think anyone here is trying to tell you to not do it, but based on past experience if you continue with your stated intentions your R/C experience will be short-lived.

Good luck!

desmobob

Have you ever met another pilot that started off flying a twin?

We have a couple of pilots in my R/C model club. They say that flying R/C is much more difficult than full-scale. You lack any seat-of-the-pants feel of what's going on, and then there's the control reversal thing....

Anyway, I'd say you're pretty much guaranteed to fail. I taught myself to fly R/C models, and it cost me a few airplanes (docile, high-wing trainers). I would have crashed several more, but I put the balsa models aside for a while and flew a foam flying wing and a SPAD until I got more adept at the whole thing.

Good luck,
desmobob

KidEpoxy

My first RC flight was a twin .15, a scratchbuilt to boot with no buddybox. Took off & flew for 1.5 mins, walked .5mins, picked up balsa confetti & busted engines for 6mins. Bought foamie to learn to fly.
Fly, Crash, Epoxy, repeat
Now I fly bashed twins and land them in one peice

Suo- if you like sims, get into Aces High and fly with a bunch of guys online in warbirds, 120 guys on your team, 155 on the red team, & 95 on the other team.... that will test your mettel, and your immels & split-s

Twin_Flyer

My Feedback: (4)

The Twinstar will be aboe four times faster then the trainer!! With the trainer you have time to actually think about what it is your trying to do, while with the twin you dont! you just need to know what to do when.

Not to mention as it seems you have never even run a model glow engine, do you know how to? they need to be broken in before use. When it dies on a trainer, they tend to float somewhat so you can land them (may not be pretty but usually they will survive). the twin engine with half the wing area and twice the weight wont! If you dont keep the air speed up it will come down right now, and again, you wont really know what to do.

WHY set yourself up to fail without at least trying to do it right? If money is that big a concern, all the more reasont to do it right!

in the end you get what you pay for. While the LA is less expensive then the FX (busing vs ball bearings) the FX is more powerful. I have a Uravitch designed OV-10 Bronco with twin OS .25 FX's. Its plenty fast. My Duelist has twin Enya .45 CX engins. A lot faster, but also bigger too.

As someone else said, get s trainer first. LEARN TO FLY with an EXPIRENCED pilot! if you dont, you wil never learn, and just waisting your time and money going to a twin that in relaity you have no chance in hell keeping on one peice, not to mention you might actually hurt someone when you loose control of the plane. While its easy to get a plain IN the air, KEEPING it there isnt! And landing is the hardest part.

Sure it easy, ONCE you have learned how.

And NO sim is going to do that. Real life is a lot different then any sim.

Bill

bigdreama

Dude
The budget is the big thing........My first plane I did the old" I can do this thing." My confiedence was way up cause one day I taxied the trainer on a side street caught some air on acciddent and landed it. Well that meant I can fly right? What's the worst that can happen? Crash right? wrong.........I took it to my schools field and fired her up.

She lifted off real nice and for the most part went the way I pointed it. That part was fun, but then the wind picked up and it was all I could do to keep it around the area.....but searching for the trim tabs and trying to gain altitude to get a chance to look down for the trim tab I needed.......... the worst thing happened.
No it didn't fly into a car,..it didn't hit a dog,or the lady with the stroller.
It just flew away!
My brother was video taping the whole thing....I'm selfish, and when I realized all I had left was a transmitter, I told my brother I wished it crashed into him, he didn't understand.

All that money and time was gone we looked for three days with the aid of the video tape......never did find it.

Much like you I also soloed in 10 hours and all I had back then was a Commador 64 Computer so you can imagine what the F/S was like. Oh, the Commador 64 was like the third home computer made (you hooked it up to your T.V.)

The whole deal is this. You hear what you want to hear...Do what you want to do. These guys are trying to save you a few bucks.
The crashing thing will happen anyway. Keep going with your project, you're on the right track, only fly something else first.
Start with a sprint car before you get into an F-1 open wheel.
It's after Christmas and all the guys that got R/C planes for a gift from their girlfriends are selling them cheap. They take one look at the box of balsa, realize they actually have to build it first and get rid of them.
Crash the ugly trainer for a while, then burn holes in the sky with the twin.

Wayne22

My Feedback: (2)

There is one secret that no one has let out of the bag yet...the twinstar used to be a single! You can leave the nose cone off, mount a 40 on it, learn to fly..if it survives, put the nosecone on and put the engines out on the wing. The LA's are slugs though..plain bearings; airbleed carbs..not a whole lot of grunt there. 25FX's or Thunder Tiger Pro 36's would give way more power and weigh less....

It flies not too differently from RealFlite, although spacial perception is different. Use the "K" button to practice single engine procedures....

Twin_Flyer

My Feedback: (4)

The single engine version Im pretty sure was called the Skyvista. Looked sweet. Too bad they dropped it.

Would'nt mind owning one...

Bill

bentwings

Make sure you get someone with a good video camera that knows how to use it. Especially zoom and focus. Then post the results over in "crash stories" Edit it for some slow motion too. I really like the "I ain't got it" as the plane is augering in at full throttle in an ever tightening spin. Might not be a bad idea to mount one of those small onboard video cameras facing forward. When viewing you need to be sitting down with seat belts on or you will twist out of the chair. haha

Just remember in the real world you can't just push "reset" and start over when you get in trouble. That is unless your billfold is the same as "reset" haha

I flew twins before twins were cool. Also won an unlimited pylon event with one before it was outlawed.

olenorski

I was wondering when someone would get around to Nony's suggestion. I did the same thing with an Avistar trainer. After a straight down landing approach and an instant re-kit, everything in front of the wing leading edge needed to be rebuilt. So I put a false front on it and located engine mounts on the wing, which needed to be recovered anyway. The power was changed from a ST 40 to two OS 25's and now it is a twin Avistar. The power is roughly the same, the two 25's being compared to the 40, but the airplane is a little heavier and flies faster, just like Twin Flyer was saying.

Dave

Suo

How do I convert the Twinstar into a single. It would work well with the reduced wing loading.

Wayne22

My Feedback: (2)

..there is a firewall already there (not sure how thick it is)..all you have to do mount the engine on it, and drill holes for the fule lines and throttle cable.... You'd have to mount a tank in the fuse, and find a place for a throttle servo...not too difficult..