LoneRanger

My Feedback: (1)

Guys, I want to build a C-130 and have always wanted to !!

I have lots of logistical problems that I can think of-

#1 the biggest is the wing, handeling 4 .049 sized motor's and Flaps, and Ailerons~
all inbedded into a very large, very Long, and fairly thin wing.


thoes of you that know about the JKAerotech slick mount knows it is a great canadite for the motor pods due to having the fueltank right in one complete unit.

ummmmm the fuselage should be fun more than anything else, but where can I get some 1/4" or 1/8" plywood formers cut out for the fuselage? and how do I do it? I dont have any cad programs so that is out-



also, retracts will attempted to be used for mains AND nose,

and possibly some kind of other "cool" stuff.


my thoughts are something like a 60" wingspan, or possibly a little bit larger fuse needs to be scaled accordingly-


ALL help and idea's would be greatly appreciated.






some other threads have been brought up before but I want to realy put this stuff down on paper-

my blue angel realy has me goin for a total scratch build that's a weee bit more complex!

ok, I LOVE YOU GUYS !!!!!!!!!




L.R.

wild fred

My Feedback: (3)

well, 60" would be a little small. thickness of wing poses no problem to strength, use a full depth spar w/ 1/8x1/4 spruce caps. slickmount probably wouldn't have enough fuel capacity to get all four going in sync and provide enough run time w/ safety margin to keep all running until landing. but at 72", the nacelles will be at least big enough for 2 oz. round, maybe larger.

There have been several done, including foam ones, etc. I would build out of balsa. 72" span, at least. shoot for 5 lbs, no more than 6. fuse fairly round, is flat on bottom toward rear. Make center keel in profile,draw formers w/ a compass and flexible straightedge, former every 4" or so, sheet w/ 3/32x3/8" or so planks. will be light. I would mount mains on a sliding track angled in the fuse w/ a jackscrew converted servo on microswitch limiters. You also will need operating doors and loading ramp, and then you can fly low and do hot l.z. cargo drops!

can you tell that I've been toying with the concept for several years, too?

BMatthews

60"? Nope. Go larger. An 049 will easily handle 220 sq inches if wing area based on your basic 36 x 6 1/2A model and in fact will fly very nicely at 25 or so oz and 300 sq inches for old timer Texaco models (the 25 oz is WAY overweight but with a 7x4 they still get an uphill glide. With a 6x3 it's sporty time).

Based on those numbers you could look at a carefully constructed model that has about 900 sq inches of area and weighs in at around 100 oz or 100/16= 6 1/4 lbs.

It won't do loops from level flight but I don't see any reason it wouldn't fly as per the original.

Practical issues like the naccelle and fuselage cross sections may dictate a slightly smaller model but I wouldn't consider going below 750 sq in if you can avoid it. You're wanting to carry the flaps and landing gear and all that other stuff right? You'll want wing area for that. This one is going to fly in the wing and not the engines. If required I'd cheat on the naccelle and spinner sizes a touch to thin them down to fit the 6 inch props.

There's a method to my madness at these sizings. I HATE seeing DC-3's and other models like Hercs that fly more like a Mustang or F18. These are SLOW flying aircraft in real life. To get the full impact in my book you need to emulate that performace.

Didn't Skip Ruff (I think that's the name) fly a C130 that was about 10 foot span on 4 x .20's. I know they weren't oversized engines but I may be a bit out on my sizing.

wild fred

My Feedback: (3)

bmatthews is right about scale speed. the f104 is large for a 1/2a jet, but everyone that sees it fly thinks it's blazing fast! it is no faster than other 1/2a's, really, but at that size, it gives the perception of being fast because people think it's a much bigger airplane. Weight is the key, will do fine at the numbers we are suggesting if weight is right. I had posted a link about a speed 400 one a while back, was about 6' and only 4 lbs- electric, too, so a glow one should be attainable at 5 w/ retracts, flaps, rudder if built right.

here is link on foam one again http://www.ralphweaver.com/c130.htm

LoneRanger

My Feedback: (1)

yes I agree I do not want an f-16 or anything fast I was trying to think like a glider, realy low wing loading-.



anything else?


L.R.

LoneRanger

My Feedback: (1)

that C-130 is about right, but it even looks smaller than I was thinking LOL and it was a 78-80" span!

I have seen that one-




L.R.


p.s. conformal fuel tanks inside the wings mabey?

wild fred

My Feedback: (3)

well, 2 main spars at least to outboard nacelles to keep from torsional flexing. one outboard of nacelles will probably do. sheet l.e., capstrip or sheet entire top if you like looks. I wouldn't sheet entire bottom, though. nosegear easy enough to do. springload main doors and gear will push them open.

now, how are you going to set up the water injection and are you using r.a.t.o rocket packs?

LoneRanger

My Feedback: (1)

Ummmm yeah, what you said-


L.R.

wild fred

My Feedback: (3)

I don't know how big the nacelles will be in scale, but at least a 2 oz. round will fit in nacelles. the 2 oz. flat one that looks like a squeeze bottle will work in wing, but round works really good. if big enough, a 4 oz. hayes slimline might fit; you could fly it for an hour!

matchlessaero

this way before, but considering my latest projects with hotwired foam and light glass cloth, I know it could be done if it hasn't already.

Start with a profile of the fullsize(model) fuse- possibly built up from balsa. Cut some blue, pink or white foam with a hotwire to match the cross section halves- would look like a bunch of foam letter 'C's. Glue them to the profile until you have a fuse lookin' thing in front of you. Sand to final shape and glass with thinned epoxy resin or polycryilic (waterbased?). Should be strong, light, and could be very faithfull to the original plane......

Good Luck!

LoneRanger

My Feedback: (1)

I think I would prefer a built up balsa and ply fuse~
The Wing I think would be super easy to do using a foam wing core however I dont know if it is feasable or not - (?)



easy may not always be better~ ?








L.R.

LoneRanger

My Feedback: (1)

hope this works~


L.R.

BMatthews

A quick Paint shop job with that rough 3 view shows that for a span of about 78 inches the spinners will be about 1 1/2 inches in diameter. Like I said you won't have any problem finding room for the engines in the nacelles of any sort of decent size model.

For that same span the fuselage works out to about 8 inches in diameter for the basic circular shape. Not a bad size at all. This, of course, give LOTS of prop clearance.

The biggest problem I can see is that the outer wheel track is only 9 inches wide...... no cross wind taxying for YOU.

A very rough wing area calc shows 624 for that wing span. Quite a bit lower than I'd like to see. I'd say go a little larger. Perhaps 84 inch span. That gives 750'ish sq inches and still keeps the fuselage and nacelles roughly the same sizes. A fair trade off size that ensures you can build it fairly light thanks to a resonable size and still have the wing area to carry the load for all the "stuff" you want in there.

The wing section is unknown but from the drawing the original is THICK so you could easily use one of the thicker glider airfoils such as the Selig 4233 or 7062 for the center panel and taper that out to something thinner for the tips.

You're gonna want to use "lots of air" in your construction to keep the weight down.

As for the wings it's possible to build foam core wings that are as light as built up balsa but it's not easy. I'd vote for the built up option. Full D tube out to the outer engine and perhaps just spars and turbulators from there.

First of all before anything else though.....

YOU NEED A BETTER DRAWING.......

If you find one with lots of fuselage cross sections perhaps you can just get the drawing blown up and build off of it directly.

DICKEYBIRD

Well, I guess I'll check in with my thoughts. My "Twin Lizzie" has 408 sq. in., Selig S8037 16% airfoil all the way out, weighs 35 oz., has 2 detuned TD .049's and flies with authority, ie: hops off a grass field in 15 to 20 ft., flies "on the wing" at 25/30% power, will do multiple loops at 50/75% power. So, like Bruce, my vote is to go big, say 800 to 850 sq. in. ***IF*** you can stay COMMITTED to building light.

I'm drawing a CAD plan for a Convair 340 project (on the back burner for right now) that has similar construction problems to your Herkey Bird. I have 4 methods theorized (think built) for the fuse const.:

1) Laddie Mikulasko's method of building a balsa stick box with several semi circular balsa bulkheads with sections of white 1 lb. foam glued between them and carved/sanded to round shape with brown paper/thinned Titebond covering.

2) Same balsa box with bulkheads as above but covered with pre-moulded balsa sheeting (wetted and wrapped around PVC tubing mold), nose and tail sections carved & hollowed from pink foam covered with paper.

3) Basic fuse "tube" hotwired from pink foam with about 1/2" wall thickness, nose & tail sections carved & hollowed from pink foam & covered with light glass cloth and epoxy or water based polyurethane.

4) Fuse bulkheads all drawn in CAD with fuse split down the center, multitudes of stringers, built like a rubber model...do 1 side 1st, then add other bulkhead halves and stringers to finish the other side....praying that it doesn't turn out to be the dreaded "BANANA."

Here's a crude pic of method #1 front view, #2 similar.

LoneRanger

My Feedback: (1)

if I increase the wing to 80" why not increase the fuse to match it? I dont see adding very much weight to the plane doing that- or I could build the "other" version which is streched by about 17 feet~ It would compensate for the bigger wing-


L.R.

I'm off on an internet search for better pics!

well after an hour and a half of looking I could'nt find any better schematics sooooo any one want to try and dig up some stuff in thier spare time?

it is the C-130J-30 that is the extended version FYI!
but I know where the lengthening occours in the airframe so If I choose to lengthen the fuse it would be an easy Mod~

L.R.

BMatthews

I didn't have better numbers for the fuselage because when I blew up the image it was so rough that I'm just guessing on the actual fuselage sizes. Of course it'll get bigger as the span grows.

To add to the construction possibilities some of the electric guys have been doing glass cloth with the new Minwax PolyCrylic instead of the usual resin. May just be what the doctor ordered.

I also had very good luck a few years back with newpaper and thinned white glue. Strong and rigid. These days I'd sub the Polycrylic for the thinned white glue.

I like that idea for the stick box and white foam over. Use the newprint for the unidirectional curved areas and glass cloth for the compound areas.

beenie

My Feedback: (9)

I used the Polycrylic and .7 oz glass on the P47. With 1 layer of glass and 3 or 4 coats of Polycrylic, it made a pretty nice finish. I think that it may even have been stronger than the same glass and 2 light coats of epoxy. I would love to see the finished product. I am also considering a 1/2A twin, just not as ambitious. Probably a Shrike Commander.

wild fred

My Feedback: (3)

rcm has plans for a simple shrike commander w/ ace foam wings!

Troy-RCU

My Feedback: (1)

You are braver than I to keep four small glo motors running in tune. My C-130 is about the size you are looking at, 64", though it's all glass and molded. It is five channel: ailerons, elevator, rudder, throttle, and split flaps that pop out the bottom of the wing. I didn't go the retract route because it adds more mechanical complexity than I wanted to tackle on the project, though, it doesn't suffer from looks in the air with unretracted gear.
I am running four 7.2V S400 direct drive on 6.5" props. Could really go to 7" but I haven't done it yet. All up weight I guestimate at 75oz. I've seen many Hercs done in this size made strictly from foam and covered with glass and polycrylic. The problem with foam is always fuel proofing so you'd have to substitute a nitro proof laminating resin for this endeavor. Many guys have done the hot-wire cut fuses and foam wings with great results (light and strong). Here's a recent thread from the Ezone:
http://www.rcgroups.com/forums/showt...highlight=c130

my C-130: http://www.rcgroups.com/forums/showt...highlight=c130

BMatthews

Hey Troy, does your Herc still have that glider like floaty slow flight like the real ones do? From those numbers I suspect it flies great but may be a fair bit faster than proper scale speed.

I've seen Hercs fly at a lot of air shows and I must say that the model type that most closely reminds me of the full sized Hercs on landing approach are the modern flapped gliders with the nose down and heading for the scoring line. Our Canadian DeHavilland Buffalos are much the same in this regard as are many other short field transport types.

Even at full bore their high speed passes aren't exactly awe inspiring. They just aren't that kind of airplane.

I also agree that this is one model that you can easily get away with having fixed gear on. The full sized one barely sticks out even fully extended. And our models don't exactly need the streamlining.

LoneRanger

My Feedback: (1)

Troy, I have seen that thread, and others but I think I am leaning towards a balsa/ Ply construction on the fuselage for some reason I think I can keep it lighter that way~

keep up the good work boys!


where can or how do I blow up some of these pictures and schematics?




L.R.

LoneRanger

My Feedback: (1)

Hey ya'll check on E-bay and look at these plans this guy is selling- it's a 64" wingspan C-130 for .10-.15
size motors


here is the item number

Item # 3122810234

*********!




tell me if ya think it'd be worth 15 or 20 bucks to get them just for kicks or not-

L.R.

LoneRanger

My Feedback: (1)

BUMP----- e-bay plans ??????





thanks,
L.R.

beenie

My Feedback: (9)

That RCM Commander looks ok, but I may be looking for something a little more scale, but maybe a little research into the airplane's shapes will make me like a simple model. Those long retracts would be cool too.
I would have to agree that those transport planes are like slowfliers. I will never forget seeing a C-5 in the traffic pattern at what I was told was 180 kts. It could have passed for a slow-flier. It seemed as if it was just floating around the pattern.