Rudolph Hart

Can you post a pic of the falcon ed as it does'nt ring a bell and as you know that was a long time ago.I mostly built off the fold up plans in the middle of the only rc mag in town those days.From memory my raciest engine was a .049 cox.Can't remember if they called them baby bees or what.A flying mate had the black widow version(i think they called it that)and i was envious!..it was out of my pocket money range at the time

Flying heavy underpowered rc control line models and waiting for it to swing round into the wind and it slows down rapidly,no centifical force any more and running backwards to keep the lines tight.Young and keen was a lot of fun

frets24

My Feedback: (15)

Yeah those were the days. I had the Sr Falcon with a K&B 61. Plan was to get it built, get good with it while building a Royal P-51 over the summer, transfer the engine and be a model warbird ace in 3 mos! big dreams at 17! now 28 yaers and counless sportplanes and warbirds later the P51 remains unfinised, THe K&B in a box somewhere and the Falcon just a fond memory after numerous crashes and repairs. P51 now has all beginner builder mistakes repaired, glass coat is done and ready for finishing...gonna fit it out with a saito 100 and a keleo functional exhaust.

heres some net grabs of the falcons

w8ye

My Feedback: (16)

Actually the Falcon was just a Stick type plane with a canopy on top of the wing. It was more modern looking than Kraft/Jensen type

The Ugly Stick had a thicker airfoil and the antique trim.

NM2K

My Feedback: (14)

-


Here is a picture that I borrowed from the earlyrcmodels.com website. I can't get to my old photos at the moment.


Ed Cregger

w8ye

My Feedback: (16)

That one appears to have the early tail like they had in the late 60's and 70's

The recent newer MK II ARF has a swept rudder but if I assembled one I think I would take out some of that dihedral?

PearHead

Good Day, Gentlemen!

I just got my 1.25 running O.K. with a Perry VP30 setup. If I may tap into the vast knowledge out there, I was wondering about a couple of things:

Does my fuel-consumption rate sound "normal"?
I get just-over 1/4 tank left after 9 minutes of "Sport-Type" flying (17oz tank).
Not sure what info helps so here's a bunch:
- Needle set slightly rich (200rmp off peak)
- Sealevel
- 14x6w prop
- Perry VP30 with bypass line

My second question is:
It seemed that as I approached the ideal LSN setting, the engine started taking longer and longer to settle into idle. Right now, when I go from full-open to idle, it drops to the 3-5K rpm quickly and then takes 3-5 seconds to settle into the 2Ks. Is that normal and what causes it?

Thanks to everyone for all the great info out here! I've learned a ton from you guys.

Pearhead
#617

w8ye

My Feedback: (16)

Your low speed needle is not close to ideal yet

Your flying fuel consumption sounds typical

PearHead

Thanks w8ye. I'll keep turning in the LSN and try to get it to round 3rd base.

And just because I'm curious, do you happen to know why this window of "hesitation to idle" exists? I call it a "window" because if I richen it a half turn or so, the transition to idle improves.

Thanks again!

ph#617

w8ye

My Feedback: (16)

I just roll with the punches.

I discovered the hard way that a Saito 56 has a false lean peak in the high speed in certain situations. So I feel around for it and see if I'm in the false peak.

NM2K

My Feedback: (14)

Why would you remove any of the dihedral? Afraid it would mess up your eight point rolls?

I don't understand why folks think that dihedral removal is an automatic improvement for all model airplanes. Not you, Jim.

With as much dihedral as is shown in the picture in your post, the only real difference would be how much aileron you would have to continue to hold once a turn is started. With no dihedral, you simply bank the model and return the aileron stick to neutral. With a little dihedral, depending upon the radius of the turn, you will have to hold a little aileron to continue the turn with the wings banked, with as much dihedral as is shown in the photo, you will have to hold a fair amount of aileron to continue the turn with the wings banked. I know that you know all of this, Jim. I'm just elaborating for the folks that may not have stumbled across this just yet.

On the other hand, in calm/dead air, the more dihedral one has, as in your photo, once the model is lined up to land, you seldom have to worry about keeping the wings level. This is not necessarily true if all of the dihedral is removed, but a little dihedral, as you suggested, might be enough to keep the wings level. Too bad we do not have a system that permits us to vary the dihedral on an existing wing so that we can vary it after flying in order to get it dialed in perfect for our particular model.

In turbulent air, the more dihedral your model's wing has, the larger the variations in the yaw and roll axis will be experienced. Those flying in predominently gusty wind conditions might want to reduce the amount of dihedral for this reason.

If we old guys don't tell the newbies what we know, how are they supposed to learn?


Ed Cregger

w8ye

My Feedback: (16)

I fly mostly sticks with no dihedral and they are good in the gusty conditions that I've been flying in.

I suppose, in reality, they should have a little anhedral to meet both demands as Moorman always bring up? Then they would be a low wing plane flying upside down.

NM2K

My Feedback: (14)

Yep, if we were interested in eliminating roll coupling with our stick type models, anhedral would be the ticket.


Ed Cregger

Rudolph Hart

Thanks very much ed.A nice looking sixties paint scheme too!

Pearlhead are you sure you have a 14x6 on your 125 or am i misreading that.My 82 swings one of those.

Capt Lou

My Saito FA100 burns about 1.25 ounces per minute so your engine's consumption is within that range. Do you have a velocity stack on your engine? This would help you a little.

Regarding your idling, break in the engine a while, several gallons, befor eyou play with the setting

PearHead

Very observant, Old Fart - My brain meant to type, "16x4w"

Hobbsy

My Feedback: (102)

PH, the over rich mixture slowly cools the glow plug at the reduced throttle setting, when you get the mixture right you'll have to reduce the throttle opening at idle to get it to slow down.

PearHead

Capt Lou, thanks for the advice. I'll go ahead and play with the LSN a little now to see what happens, but I'll definitley readdress it after a few gallons.
Regarding the velocity stack, no, I don't have one, but it's on my "future modification" list.
Thanks,again!!
pearhead

Hobbsy

My Feedback: (102)

PH, why such a snall prop, that prop is too small for the 1.00, Thanks, Dave

PearHead

Hi Hobbsy,
I picked that prop based on what seemed to be the most popular size/type for the guys using the engine in 3D planes (I have it in a Funtana X100). I haven't done a lot of 3D, so I just copied everyone else.

The engine maxes out at 10,400rpm with that prop and will idle reliably at 2700 (that idle being with a poorly adjusted LSN, as you know). Is there a way I can tell if I am underpropping this 4 stroke? (This happens to be my first 4-stroke, as well).

Thank you, very much for all your recommendations and help! I greatly appreciate it.

PH

Hobbsy

My Feedback: (102)

PH, I consider them over propped at 10,000, (except the little ones), but you're talking 3D which is completely foreign to me. You're wise to go with what the 3D'ers say. Thanks.

w8ye

My Feedback: (16)

The 3D prop for the 125 is a APC 17-4

PearHead

W8ye, Thanks for the guidance. I was wondering how the 17-4 got named "the 3D prop for the 1.25"?
It seems to make sense looking at the prop chart in my manual, and I'm definitley going to give one a try. Just wondering if there was anything out there that I can read about what I can expect out of that setup.
Thanks. ph

w8ye

My Feedback: (16)

The 17-4 really buzzes when you give the engine the throttle pulling out of a hover

Vertical thrust like you wouldn't believe

PearHead

Sold. Thanks, w8ye.

Capt Lou

Pearlhead:

If you use a velocity stack, make sure you place a gasket between the carb body and the stack body. When you buy a velocity stack, it does not come with a gasket and there is a small space between the two bodies that needs to be sealed. If you don't do this, the stack will not be less effective. I don't know why Saito doesn't supply this gasket with the stack but you can use an o-ring or fabricate one from a faucet washer. There have been many comments made about this matter on this thread.

Capt Lou