Strykaas

Hi all
I'm currently thinking about the mods I could perform on the Force One kit waiting nearby.

1. My first considerations are about the engine. While I want strong power, I don't want to go to the heavy side too quickly (see next items). It is stated for a .46 sized engine. My first idea was to use the MVVS .49 engine, which is powerful AND above all can be configured into a FIRE setup which would make it very nice for a pusher configuration. I'm now moving on to a piped webra .50 P5 (or maybe .55). I also still have a NIB SJ50 (side exhaust), but I suspect a pusher configuration is not the best for this jewell in the cooling department... Bob, what do you think ? Has anyone ver tried a pusher configuration for this engine ?

2. Airframe. I have nice ideas to improve the look of this delta (which I think looks like a bird with its necked shaped front fuse). Basically, I would increase the nose length, shape it differently, a bit like those modern radar evading shapes (somewhat facetted shape), and above all install sponsons on the bottom of the wings to accomodate...

3. Retracts. Pneumatics actually. They would be located in the mentioned sponsons, as the wing is too thin to accomodate retracts.

4. Rudder. Micro servos located in the back section of the sponsons could move rudders.

Does aynone think this project is worth it ? Am I bound to fail with this probably heavy setup ?

PS: I'll provide a simple 3D CAD version of this project if this yields any interest.

Crazy4Flight

My Feedback: (540)

farce-1 (nitroplanes kangaroo)

1.5 flight till its death

OS .50 SX and pitts muffler

spring air retracts (305?) they were made for the greatplanes patroit .40.

dual rudders

elevons programmed

hitec thin wing servo on the actual elevator....


if you have a sport Jett 50 Jett Engineering has a muffer for pusher configuration ($75.00)

or you just plug the exaust hole and put a vent hole & tube in the other????

BOb

freakingfast

My Feedback: (3)

You wont make it too heavy if I didn’t Do think about a little more reinforcement on the rear upper fuselage sides were you cut the hatch near the firewall, it’s just thin balsa there. And at the bottom of the firewall.

Yes it does look like a birds head and it looks like you got the fix.

Rudders on this thing?..... I don’t think it’s a good Idea, you will need some weird mixing or the rudders will just make it roll. If I recall, the instructions even warn about doing that. Could be good for spoilers but other than that it’s just more weight IMHO. The thing lands slow anyway, nose high like the space shuttle if you want.

I used Golden Rods for linkage for ailerons and if I had to do it again Id do away with the plastic push/pull and put the aileron servos in the wings as far forward as possible to keep the CG the same as stock. Id put the servo hatches on the bottom and try to keep the servo arm inside (clean). By the way, keep in mind it’s a delta and it needs a stronger than normal 40 size aircraft control forces to realy kick it around.

Retracts could be a cool idea and will greatly improve the speed.

The fuel system needs special attention. The clunk should be to the rear of the plane! The other problem is the carb very high in relation to the fuel tank if the engine is mounted upright. You could rotate the engine, but that may block (drag) a lot of air flow to the prop with the cylinder that close to the wing. Unless your engine’s carb has very good draw or already has a pump (like a YS 45 SE) the use of a Cline or Irongate regulators(on demand types) would be a good idea for a stock carb.

I used APC and Master Airscrew pusher props. I ended up favoring the MA because it was much more resilient to damage from the small stones thrown at it by the nosewheel.

Hope this helps.

combatpigg

My Feedback: (3)

I think the problem with the "looks" of this plane is the swept up nose. Make the front end look more like a F-16.
I don't think retracts are a good idea if you are interested in speed, deltas need to be built as light as you can possibly build them in order to be fast.
Belly land it.

freakingfast

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Some of you guys are so lucky, if you belly land it around here you tear out your belly. Just tufts of weeds that will send it spinning into rocks pushed up in the gopher mounds or you have choice of 5000 grit asphalt.

freakingfast

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This is what she looked like. I sold her to a dentist in Livermore, CA that just had to have her last year. I hope it's still in one piece. Several years ago the hatch came off and went through the prop[:@]. In the new hatch pictured, I took out some of the swoop in the top to help loose the bird look.

combatpigg

My Feedback: (3)

That is a big improvement in the looks department. I scratch built a delta a few years ago that looked good on paper, but ended up with that "bird head look". I never realized what didn't look right until you pointed that out.
Every Balsa Usa creation I ever saw at the club field has been an overweight and slow disappointment, even with powerful engines. Years ago I tried my hand at improving on the BUSA deltas with a home built job, but ended up with more heavy junk. Weight and drag really add up quickly on these triangular ships.

Strykaas

Thank you for your useful comments.

I think I have seen other configurations which featured a 90 deg rotated engine in the same configuration, which was apparently not much of a problem...

Well, here are my plans :

1. Retracts (Eurokit set) : belly landing might be possible but take off is an issue anyway, doable with a dolly, and those are forbidden at the field.

2. Lengthen and modify the nose, should not add much weight ;

3. 90 rotated engine, OS46SF or Webra .50 + mousse can muffler first.

4. No rudder;

Purpose is not to be ultimately fast, I have other airframes for this . A nice looking and good flyer is what I am targeting first. It shouldn't be slow however.

More to come.

Strykaas

Well, let the fun begin [:-]

freakingfast

My Feedback: (3)

For me, It’s a balance thing. I see smooth air over the wing then bam, a corner created by the cylinder and wing. Yes it may mean little but I have the mindset; if it doesn’t look right it probably isn’t, so I just couldn’t make myself do it.


CP, I tend to use allot of glue on joints. but I hate puddles or unnecessary fillets of glue and it came out not too bad weight wise. It flies very light and was quicker than any other similarly powered, non-retract sport plane (like a tiger not a patriot). The main issue holding it back were those three big doughnuts, retracts would have made a ton of difference.

freakingfast

My Feedback: (3)

One thing to mention, it has a unique sound, like a howl. Not overly loud or annoying, but it usually got everyone’s attention in the pits on a low pass over the runway. This sound is probably from the mid mounted engine and the prop chopping air through the slot, siren like. Kinda like a voice coil in the middle of a speaker diaphragm.

In flight for some reason it always looks faster than it realy is to the untrained eye. You get a lot of “Man how fast is that�.

Strykaas

Yeah freakingFast, I see your point. Maybe I could just install it upside down. It would solve the tank location problem as well. Or maybe install it rotated 90 deg but slighty higher...

Btw I like your finish scheme very much. Wasn't it a bit hard in the orientation dept when flying it ?

Strykaas

Here are the latest pictures of my CAD work [8D]. Blender (freeware) is such a cool and easy to use modeller. I recommend it [sm=thumbup.gif] !

Tell me what you think [:-]

freakingfast

My Feedback: (3)

It was vary easy to keep oriented, I could easily see the bright red top or green bottom stripe on the black.

Strykaas

Update.

combatpigg

My Feedback: (3)

Beware that too much side area ahead of the CG can cause the plane to wander side to side. Looking at your rendering makes me wonder if you could borrow some of the lines of the Mirage series and see what you come up with?
It sure is nice to be able to see your ideas in 3D. [8D]

freakingfast

My Feedback: (3)

He actually added side area aft of the CG. If memory serves me the CG was a inch of so forward of the firewall.

freakingfast

My Feedback: (3)

Take care strykaas, not to add too much weight aft.

bob27s

My Feedback: (19)

Build it

keep in mind the landing gear size - and the prop arc.

Deltas tend to take off and land at higher AOA than conventional designs. So size the gear to prevent a prop strike at around 10deg nose up or better.

Strykaas

Yeah I could borrow Mirage lines and try to see what it gives... It would make the build much more complex, though [:-]... I might give it a try just to see... I want it simple first

A canard configuration interests me as well, but Laddie Milkulasko in person said he tried them, and it did not improve things, the Force one flew worse [&o].
I have tilted the rudder fins a bit also...
Here is an example of the design I'm thinking of :

Strykaas

Sure I did. It's very easy to check this with CAD . In this dept, I intent installing prop-guards, like those pictures below. What do you think ?
Did you see my question at the very beginning of this thread regarding using a SJ 50 in a pusher configuration ? Would it harm the engine by not being cooled enough by prop air-wash ?

Strykaas

I have worked on it a bit, trying to improve prop blanking due to fuselage... I have therefore squeezed the rear section of the fuse leading to the engine mount.
I also took the idea brought by excellent Steve Elsey (author of the awesome Crusader II design), and tried to fit it into my design... The basic idea is to hide the engine behind a hollow cowling hiding the engine under most viewpoints. I can mount the engine upwards in this configuration as the engine is not very visible . Steve Elsey still mounted his engine rotated 90 deg with a tuned pipe under the belly [8D]. I have to think about it [:-].

Blade47

I want one!!!!!

cheers

Strykaas

One more render (ray-traced) :

combatpigg

My Feedback: (3)

That's looking very good, clean and simple!