I'm a relatively new flyer (still flying my trainer, but hope to have my BigStik 40 finished soon), and I'm looking for a twin engine ARF (I just don't have the time for a kit right now) that I can put two OS 46 FX engines in. I think I need to go with a fixed gear plane (to keep it simple for now), and would like something that is within my capability to fly. Any suggestions?

Mike

Hobbico Twinstar ARF.

http://www2.towerhobbies.com/cgi-bin...&I=LXJPH0&P=ML

If you run into clearence problems between the props and the side of the fuse--just put a 9x6 3-blade prop on the engines.

With .46 FX's you'll need quite a bit of throttle management, and I'm not sure that even the 9 X 6 prop will be enough. Probably will need something more in the line of a 10 X 6 or 10 X 5 three blade. The FX is capable (and even likes) to swing an 11 X 6 or 11 X 7 prop very efficiently. 11 inche props will cut the nose off of the twinstar, so 10 inch is all that is really possible. Therefore, the 10 X 6, or 10 X 5 (if available) would be the best choice.

Now, to the good stuff. I have twin 40 LA's on my twinstar, and run 9 X 6 three bladers on it, and it will cruise at around 75 mph (as clocked by a handheld radar gun). So, a 46 FX turning 10 X 6 three bladers should get you up in the upper 80's. That might be enough to rip the surfaces off. Flutter would definitely begin to be a problem

I wouldn't recommend the .46 FX's for the twinstar, and I wouldn't really recommend the twinstar (or any twin, for that matter) as a second or third plane. Why? A few reasons

First, and foremost, there's the engine out situation--can be devestating if you are green. I know there is a lot of outthrust built into the twinstar nacelles, but it's still something to contend with.

Second, there's the tuning. You need to get the engines running at close to the same RPM's, and you have two engines to tune, and syncing them can sometimes be a challenge.

Third, the twinstar (as well as most other twins) has the glide ratio similar to that of a set of keys. In other words, pull the power back, and she's coming to earth! It lands fairly hot because of this, and has a fairly significant wing loading.

There are other reasons, but I'm out of time. Twins are luring, I know. I love the sound of my twin, but I had flown 5 or 6 other planes before I got into it. I still don't know how well I can handle an engine out--i've not had one go out yet. I've had both go out--fortunate--but not just one. WIthout any power, the thing just came on down like a brick. Really had to work to get it down in one piece.

I've not been flying long, but I've flown a lot in my short time. Experience is your friend--especially with twins. In any case, I woulnd't put BB .46's on a twinstar.

Happy flying!

I thought maybe the 46's on the Twinstar would be a bit too much, is there something else out there in an ARF?

Eventually I want to build a B-25 kit, and possibly use these engines in it, even though 4 strokes sure would sound better, but that is too much for me to take on right now. My uncle (who passed away last year) was a mechanic/gunner in a B-25 in the Pacific during WWII, and I would like to do one up in his squadron colors if I can.

I would say that if you are a new flier, the recommendations you have gotten are wrong. The TwinStar is designed for a .25 and flies well with a .25 or .32. With 2 OS .46FXs, it will be over powered, which can get you into trouble when you lose an engine; it will be nose heavy, making it heavier after you balance it, the tanks are only about 3.5 ounces so you'll have a short flight time, The clearance requires you to use a 3-blade prop-more costly and header to find. An expert will be able to handle it, but if you are new, you won't be able to. Two .40LAs, by the way, are the same as 2 ball bearing .32s for power. Several of us in my club have TwinStars with either OS .25s or GMS .32s and they fly great.

For 2 .46s, you need something like a Cedar Hobbies Twin Stick, a larger plane that was designed for 2 .40-.52 engines. [link=http://www.cedarhobbies.net/index.php?id=product_desc&product=5]Twin Stick[/link]. I fly mine with GMS .47s and it flies great. Easy to land and does all the acro except 3D. It also handles a single engine well. And, it flies like a Stick, which I know you can handle.

You also need to check in to the RCU Twins Forum and talk to the people there.

Ed,

That looks like a great plane, and would be a great addition to my Stik fleet (I also have a 60 waiting to be built). Did you make a mod to move the elevator and rudder servos to the tail, and is that necessary to balance?

Bet that Twinstick would fly *****in with a pair of ST .51's. I briefly had a Twinstar with a pair of Saito .30's. Destroyed it on the second flight.
Whatever twin you get MAKE SURE BOTH ENGINES ARE FULLY BROKEN IN AND RELIABLE AS ALL HELL. One engine out on a Twinstar makes for a very interesting time however it comes out.

SkyDemon ,,,
The *best* info given so far has been what Ed Moorman has given...

Unless you have the experience to fly performance twins AND to
do major repairs,, using the .46FX on a Twinstar is HIGHLY **NOT**
recommended...
If you look into the multi engine forum at the *Official Twinstar *
thread just about all your questions will be answered there...
http://www.rcuniverse.com/forum/m_26...tm.htm#2688899

I have done Twinstars with just about everything from .25LA to
doing what I named the Phoenix that uses .52 TS motors... I
can tell you the smaller motor'd ones fly soooo much nicer,,
and would be better for a lesser experienced person to fly and
LEARN with...

As Ed noted,, the more motor that is used the less flying time..
Plus with hot motors an engine out will rotate the plane rather
quickly...

The Stick that Ed suggested is a good plane for the .46FX's..
But it will be somewhat of a hotrod... I flew Ed's and that
thing is rather fast,, and a total blast...

Something to think about is maybe doing up a Great Planes
60 size stick... Attached is a pic of one I did and it flyes like
a dream.. The three bladed props were ONLY for looks as
it was made with more thna enough room for bigger props..
Isn't a rocketship,, but is a great flying plane..

If you want to do a Twinstar then I would highly suggest staying
with motors in the .30/.35 range for good all around flyability...
If you want a plane for the .46FX's,, do the Stick thing...

Robby,

It looks like the TwinStik is about the same size as the BigStik 60, so rather than going thru all the work to make both engine nacelles. Another plus for me right now is that the TwinStik has two piece wings. One reason that I'm building my BigStik 40 first is that the 60's wing won't fit in my car (I don't think). One of my projects for the winter is to modify my small utility trailer (make a rack and a hinged cover) so I'll have room to bring more than one plane at a time to the field

Looks like it's going to be nice here on Saturday, high of 60, so I'll have to take advantage of it, and head to the field, even though I'll just be flying my NexSTAR since Tower Hobbies didn't ship out the hardware that was missing from my BigStik 40 kit as they promised two weeks ago [].

Mike