TimeFLYING

My Feedback: (3)

I looking for a good looking twin. I would prefer something that looked like a full scale plane. and would like it in the .40 -.60 range of things and if at all possiable a kit. if you could put a link up that would help a lot

Thanks
Troy

crashnfix

My Feedback: (1)

I'm in the same situation. I bought the TF DC3, but the more I look around, the more I feel it's not the best for a first twin. I thought about the Twinstar ARF, but of course it has been discontinued. Also, from what I read, it would be significantly overpowered with 40s. The more I browse RCU, the more convinced that the Duellist by Pica would be an excellent first twin. Check out the pictures in this forum to see what can be done with it appearance wise.

John

twinman

My Feedback: (2)

Let me pose a different approach.

Kit Bashing a Perfectly Good Plane into a TWIN!!!!! Part one


There are very few multi engine arf's and few kits,compared to the single engine types for the modeler to choose from. If you want to get multi experience before the bank is broken on that multi engine war bird, consider "bashing an ARF" to a twin.Yes, the Hobbico Twinstar is good, and an excellent flyer, but small compared to the larger war birds..

Ugly Twin Stick

One way is to find a long fuselage single such as .60 size ugly stick, put nose cone over the center engine mount and add nacelles to the wings. Warning, the wing loading sky rockets!! Forties will not fly this well. Go to two .60's, add 8" to the wing and add wing plates on the end. The result flies well and was the subject used for my experiments with various ideas with twins.

Ultra Sport 1002

Got an Ultra Sport 1000? Need a twin? Create the US 1002. Put an eleven inch tapered nose cone over the original engine mount area. Suggestion, the fastest way is to use four 1/2 balsa triangles, glued to a point and shape as needed with sanding wheel. ( Remove the original engine first....Let's not go crazy!!)
I added wing plates to the end of the wings that extend 3/4" outside of the airfoil. This is necessary to compensate for the additional weight of the two engines. Make nacelles of 3/16" balsa with 1/16" ply reinforcement inside the vertical walls. Use Grappner 14 oz. square fuel tanks. The recommended engines are healthy Super Tigre .90's with ASP 108 Carburetors and Master 14x6 propellers ( Or equivalent). Enlarge the rudder to roughly two times the original size and go to pull-pull on the rudder control. Enlarge the ailerons to two inches and full length. I added carbon fiber cloth, from Dale Brown, to the top and bottom of the wing to reinforce the wing structure. It will be necessary to increase the servo power to at least 100 oz or go to two standard servos per aileron ( Which I chose). The plane can go so fast in a dive, aileron flutter will result!!! Yes, you will do it!! Sealing the control surface gaps is highly recommended. The elevator is split for more roll response. Total 10 servos.
This plane will go straight up and flat spin like you would not believe, as well as knife edge all day. You will also wow the crowd if you can learn to hover the plane.......a twin!!!

Twin Long John

Another way is to create a "100 foot stand off-scale" F-82 twin mustang. Yes, World models makes a F-82 ARF, but is still smaller than 80" and light weight.
One plane that works well is to take two Long John 40's, combine the wing to 82", two fuselages side by side. I set my engine spacing at 12.5" to use 12x4 props, and a single horizontal stabilizer. You must make a brace, to hold the fuse's inline for transport, to take the place of the wing and support the two fuselages. I learned the knife edge circle with this one and still fly it today with two Super Tigre .45's. Instant "Twin John".
Due to the smaller size, I used one servo for the rudder and connected the other one to the master rudder with streamline tubing. Two tail wheels are necessary. I also only used one elevator servo. This is a risk, and must be evaluated on each conversion. This is not a high speed model, so to reduce weight, I tried it and was satisfied. Total 6 servos.
Again, a brace to go between the fuselages for transport and bolted in as the wing replacement, is necessary or the elevator will be broken during transport.

Twin Fuselage Ugly Stick

Still another conversion, that flies well, is to use two Ugly stick .60's and build the plane with two fuselages, as the Twin Long John. Take the arf's wing halves and glue the center joints, as normal, then shorten the center joint, which is the outer of each wing assembly, four rib spaces for only one new joint. This yields a fuselage spacing of 20" centers. The joint should be strengthened with fiber glass cloth. It is also necessary to sheet the center area of the wing, so that the fuselages will be supported from front to rear when bolted to the wing. This yields around 86" wing span. I recommend adding carbon fiber strips to the top and bottom of this wing to reinforce against the new found power and maneuverability. Two .60 two strokes fly it well and now flying with two Super Tigre .90's (More power ARGG ARGG!!) Pin the firewall with epoxy and tooth picks to stand the added forces.
The horizontal stabilizer is formed using the original stabilizers shortened in the middle. Cut the two elevators to match the fuselage spacing that you have chosen. With this type of two fuselage system, you can either put the receiver on one side and battery on the other, or can practice the concept of two receivers for redundant control. Again, must build brace for transportation to hold the fuselage's in alignment and not break the horizontal stab.
To keep the model interesting I inverted the fuselages to make a low wing model. One problem with this modification was that with such a large wing, so close to the ground, ground effect really comes into play on take-off and landing.( Did not plan on that one!!)
I added one more "Small Modification". I had extra elevator material left over, so I used it on the wing between the fuselages as a kind of extra flap for more lift during maneuvers. This "Flap" is mixed into the elevator for more response.
This plane is fantastic as far as aerobatics are concerned. The more you mix the engines to rudders, the more fun.
The two fuselage conversions should keep the props almost touching for better engine out characteristics..My twin Ugly stick is not close.The center line of the engines is 20" for more practice similar to a P-38 with wide engine spacing. Engine out is good due to the long fuse and larger rudder.
Used separate servos for the two rudders and two to a single elevator. Total 9 servos

Good Luck,
Twinman

twinman

My Feedback: (2)

Tips for Twin Conversion

1. The nose of the fuselage (Where the former single engine once stood) needs to covered. Fabricate a pointed nose cone, in whatever shape you desire, and cement or fasten to the former engine mount area. Using a solid small block of balsa, sanded to shape and hollowed, is the fastest method ( Let us not discuss tri-motor idea at this point...Two motors will be enough problems at this time.)

2. As a general rule,make the engine nacelles out of 1/4" balsa, and reinforce on the inside with 1/16 plywood in each side( On the inside) of the nacelles.

3. Use two servos, one on each engine, and "Y" harnessed together and connected, to the receiver. Mixing of the engines comes later.

4. Due to the increased weight of the additional engine and fuel tank, the wing loading goes up quickly. It is advisable, unless you are planning to practice war bird flight characteristics, of high wing loading, to lengthen the wing span by 10-15%. This will reduce wing loading and make the model fly similar to the original plane...except now the model has more horsepower, weight, and feel...ect.ect.
If, after the wing is lengthened, you still feel the wing loading is high, or the plane seems to fly "Heavy", then the addition of wing "Plates" to the end of the wings is advised to provide additional lift.

5.The once open area of the wing that will be covered by the nacelles, should be sheeted with
at least 1/8" balsa or 1/16" ply, prior to the installation of the nacelles to provide additional area to glue the new engine nacelles. Additional triangle stock inside of the nacelles to additionally mount the nacelles to the wing, is not out of order. Now you can go find fuel tanks
that, ideally will fit between the firewall, nacelle sides, and the mail spar. You might want to check Hobby Lobby and the Grapner line.They have high capacity square tanks that seem to be shorter than competitive tanks. This lends itself to this modification.

6. The wing stress climbs quickly due to the additional weight, twisting loads, forward mounting of the engines, power, increased speeds, ect. The wing should be reinforced during the conversion process to be able to stand the additional loads and stresses of flight. Do not cut the main spars for any reason!! Carbon fiber cloths or strips work well for this applies directly to the main spares. This is more important if the wing is lengthened.

7.The rudder size should be increased by up to 50% to aid in the single engine out condition. Similarly, the servo for the rudder should be increased in power, or go to 6 volts from 4.8. Remember that the battery for the plane will be drained faster than the old 4.8 volt pack due to higher current flow and additional stresses on the servos due to the extra power.

8.Now is also a good time to seal the gaps on all of the control surfaces. Due to the additional potential speed, flutter could rear it's ugly head, from where is has been hiding while using the lowly single engine.

9. Make the nacelles overly long to the front of the wing, but do not mount the engines at this time. Bolt the wing to the fuselage for a completed flight assembled plane. Make sure all servos and batteries are installed. Mount the engines to their individual firewalls. Using rubber bands around the free standing nacelles, hold the mounted engines inside of the nacelles and move forward and backward until the plane is balanced. This step reduces the need for additional weight to provide the proper model balance. When the plane is balanced, similar to the pre-conversion setting for CG, then glue, and I suggest pin, the firewalls in place.

10. The radio installation, on twin fuselage planes, involves putting the battery and servos on one side and the receiver on the other, to maintain some degree of lateral balance. You will need quite a few extentions. Or you could practice the concept of dual receivers at this time. One receiver for each side of the plane....Even split elevator is possible. I suggest using two servos for the rudders, and elevators, due to the higher forces and longer surfaces on the elevator. One servo on a 12" elevator, mounted on one end is inviting flutter!

11.Whatever you do, have fun with it, but practice before the first twin war bird on a cheaper alternative. Been there, didn't do that..don't do that!!!

12. For more on flying twin, go to rcwarbirds.com and the twins forum. My two cents.

Twinman

crashnfix

My Feedback: (1)

Twinman, that's a lot of good information. Gives me ideas. Maybe put nacelles on a four-star 60 and power it with a couple 40 FPs. I already have the engines so whatever plane I end up with, that's what I'll use for power.

Maybe I will go with the kit bash, then the Duellist, then the DC-3. This looks like a couple year plan.

Again, thanks for all the great info.

John

flying2bill

My Feedback: (2)

how about a twin stinger? simple lines, good flight characteristics, easy to enlarge rudders, might just give it a try. gotta rebuild mine any way.

crashnfix

My Feedback: (1)

Tell me more about the stinger. Kit? Brand? Retailer? Price? Pictures?

Oh, never mind, found the Lanier kit at tower. Might do ok.

John

twinman

My Feedback: (2)

Good luck to all of you and welcome to the world of multi's.
(fools)....Tee Hee
twins give you gray hair......wish I still had some....hair
Twinman

staggerwing

My Feedback: (5)

Wouldn't take much to kitbash a Duelist into a DH Mosquito.

soarrich

My Feedback: (98)

I'm no expert, I only play one on the internet......BUT;

I bought a Twinstar ARF with 2 .25FPs and five servos $85 at an auction last Saturday, I flew it today. It is anything but under powered. I would say that with 2 .25s it's perfectly powered. I was very surprised having heard that a lot of guys put 2 .40 in it, I thought it might me marginal because this plane feels like a stone when I pick it up, but it's able to climb out at 45* forever. I like it's engine out performance also, it just goes slower, very forgiving.

Rich Border

TimeFLYING

My Feedback: (3)

I just bought a TF DC-3 w/ robart retracts thanks for all of the input but now im looking for a color scheme.

Thanks
Troy

twinman

My Feedback: (2)

If you are into larger twins,as I detailed above, consider bashing the Ultra Sport 1000 into a twin.
Fantastic flyer and fully aerobatic.
Has two inch ailerons, ultimate style rudder, four inches longer wing span(86" total), wing plates, two ST 90's.
Consider mixing the engines to the rudder. Imagine powered knife edges, easy flat spins that come out instantly by merely reversing the rudder(Differential thrust), and wild hammer head turns.....OK so I have not figured out the waterfall!!
Good Luck,
Twinman

aeroscale

There's always the OV-10 Bronco available in both kit and ARF form ftom Hobby Hangar (www.hobbyhangar.com)

aeroscale

Another view......
AEROSCALE

TexasAirBoss

My Feedback: (22)

I have seen that OV10 fly. Boy oh boy is that thing fast. It had two OS32's on it. It whistled!! I mean literally!
Well, it wasn't that exact OV10, but the same brand.

Carlos Murphy

My Feedback: (72)

VQ has a nice A-26 Invader for under $300.00.
morrisbobbies.com has them as dose sheldonshobbies.com (if they have any left)

They come with fixed gear but Spring Air 202HD just bolt in as shown in the instructions.

My friend will fly his in two weeks, it should be done by then.

mulligan

I flew TF DC-3 as my first (and only) twin. No problems. As long as you are comforatable flying an intermediate low wing tail dragger, you should not fret (well, that is anymore than flying a new kit for the first time ).

I put Wankels in mine (very sexy) and an on-board glow system to avoid OEI events, but even when one engine is out, nothing remarkable happens, unless you try to make a steep turn or power up the one engine- basically it's just like dead-sticking a one engine plane- just don't throttle up!!! I was able to get to about 1/3- 1/2 throttle (again using Wankels, which are supposedly equivalent in power to .40LAs) before plane stalled/snapped. Once you get the nerve, this is fun to experiment with at about three mistakes altitude

- George