Preferred "Peacemaker" Engine Weight?

[Serge_Krauss]

Several of you have been really helpful in my Aldrich "Peacemaker" project. Thanks for that! One question that emerges from the mentions of engines and weights is the effect of the weight of the engine itself on balance and flyability. I still have several engine options, ranging from the under-performing 3.6-oz Fox .15x, for which I don't have a .01" head gasket to replace the head spacer, to considerably more powerful engines weighing up to six ounces without mufflers.

Since I've put off drilling the engine-mounting holes (it's time to drill), I still have options of engines I own or can get immediately for what I can afford  (not much. Ha!). I have the .15x, Olympic .15, green-head .23, and an old Enya .19 (probably a IV or V) coming my way. A Fox .19 or .25 (non-schnurle) are available. If I use the 3.8-oz Olympic (with smaller venturi throat), I'll have to learn to build a pretty fancy tank.

So I'm wondering what trade-offs you've made regarding ballast weights, power, etc.  What's too heavy, and what would allow for building over-weight? I just want the little (36") plane to fly the maneuvers, with line tension, but without screwing this old-er guy into the ground with combat lap times.

Are there any more opinions out there? Thanks.

SK

[frank williams]

LA25 .... OS25FP..... or Oliver Tigre 15 Diesel

[Gordon Van Tighem]

Hi Serge,
I flew a Veco Warrior (same basic size) with a McCoy .19 for a few years with good success. Of your choices the Fox .19 (or 25) might seem more attractive. (the others seem to be fast runners)

[pipemakermike]

The engine it was designed for is the Oliver Tiger 2.5cc (.15ci)  the given weight for this engine is 6 1/2 oz.

I would save drilling the bearers until the model is finished and then hold the engine on with and elastic band and move it until the CG is in the right place.

[john e. holliday]

Here's my version of the British Peacemaker by Aldrich with diesel power.  Still trying to remember how to run diesels.

[frank mccune]

     Hello:

     I do not know how many squares the Peacemaker has but in the past I have flown a Shark 15 with 270 squares with a plain bearing Fox .15 and a 7x6 or 8x4 prop.  This combination really flew well.

     Perhaps an older ST G-20.15 ,.19 or .23 would be a good choice.  These engines are real sweethearts and can be found for little money.  I have used them on the Shark 15 and a full sized Flite Streak with great success. I think that they weigh about 5.5 oz.

                                                                                                    Good luck,

                                                                                                    Frank McCune

[paw080]

The engine it was designed for is the Oliver Tiger 2.5cc (.15ci)  the given weight for this engine is 6 1/2 oz.

I would save drilling the bearers until the model is finished and then hold the engine on with and elastic band and move it until the CG is in the right place.

Hi Mike, someone gave you the wrong quote... My C.S. Oliver weighs 4.7+ ozs,

my original Oliver MkIII weighs 4.86ozs.

Tony

[paw080]

Hi Serge, you are over thinking and over prioritizing this entire Peacemaker project.

First of all this model was designed as a combat/sport model;  it was supposed to fly

competitively fast in those days. It was  intended to fly on 52' lines.  You can slow

the apparent speed by flying on 58' - 60' lines.  You can use any of your 5.5-6.0 oz

engines. You can even use a baggie/balloon tank if powering with your Cox Olympic .15;

which will give excellent fuel feed resulting in constant engine runs.  DO NOT move the

CG any more than 1/4" forward.  You've already been given advice about elevator deflection.

Another thing to consider when flying CL models with "Combat" sensitivity,  is to narrow

the line spacing on your handle; these models respond instantly to control input, far,  far more

quickly than a "normal" stunt model.  Flying this model will reveal where you want the CG located,

and just how much line spacing you want at the handle.

One last thought, just because a Combat model can change directions so quickly, this does not mean

that the model is in an unstable trim condition.  Combat flyers spend a lot of time in the circle NOT looking

at their model, they learn to feel what it is doing, this involves the stability to fly straight out of popping

a 90 degree turn, this requires a very stable straight tracking design. 

I'm guessing 58'-60'line length and an 8 X6" prop will give a comfortable and confidence inducing flights.

Good luck Serge; 

Tony 

[Serge_Krauss]

Thanks so much, guys, for the information and opinions.

Thanks, Tony, for the perspective! You are right to address handling, in that I don't really know what sort of sensitivity most happy "Peacemaker" fliers like. Frank (W), you may be looking at more of a "hot rod" than I intended, but In case there has been any confusion on which "Peacemaker" I have, it is the British version with the smaller 36" span. I have an LA-.25 that I use on my 500+ sq. in PF-II (modified, crash-survivor  P-Force Wing on new fuselage). It turns about 5-second laps with a 10" x 3" prop 2-cycling on 60' lines (comparison in photo) Wouldn't the "Peacemaker" be pretty fast and a bit nose heavy on that engine? Thanks for the perspective and recommendations, Frank M. Also, I get the impression that the Fox .15x, without upped compression ratio, is a lot weaker than the plain Fox .15 (I have PGF Chinn's article). That's why I'm looking elsewhere. Thanks, Tony and Mike for your combined info. The picture Mike posted is in my collection from the internet - probably the reason I thought to build this one. Doc - 'looks good! Gordon, I USED TO have a McCoy .19, but it disappeared from our garage after I'd left home. I'm thinking of buying a pretty old Fox .19. Yeah, Tony, I tend to over-think just about everything, even sport models.

SK

[Air Ministry .]

Some idiot that shall remain namelss has about a dozen of the Fox 19 / 25 4 bolt suckers . for some reason  .

6 - 7 turns on the needle , 10 ,  15  or 20  % Nitro and theyre V Good .

The Black prop driver ones are retimed , as are the 1/4 shaft 19s , but a 9 x 4 or 8 x 6 ( or 9 x 5 on the 25s ) and theyre intrestng and light .

However if a LA 25 was AS LIGHT , on No Nitro it would probaly ' keep up ' go all day . and stay out there , when reqd ,
allowing a tounge muffler on the LA & the Stock Tube Muffler on the Fox ( not the late one which wouldnt hit the deck well .

 So'd depend if its  2 or three flights a day ( Fox ) or All Day ( LA ) . Antigue 3 bolt fox is an unknown to me , But Don still thought well of the 3 bolt 25 . or was it a 29 .

[Dave Harmon]

Reading this about the Peacemaker sure brought back some memories and I'm thinking about building one of them now!
In the late 50's GMA lived in Tulsa and I very clearly remember him flying the original PM at the Tulsa Glue Dobber site.
He had a diesel on it and it was an Enya or Oliver....don't know for sure but he made flight after flight after flight......brrrp....brrrrrp.....brrrp.....brrrp
It was sooo cool I just could not take my eyes off of it.
Today....you can still see where the parking lot was and one circle is still visible.
I might just look into getting a diesel...lotza FUN!

DH

[GregArdill]

Serge,

From the list of engines available, I'd pick the Enya 19. I'd guess that it's pretty similar in power and weight to an Ollie Tiger.

As has already been pointed out the PM was designed as a combat model, so you need to expect spirited flying style. Build it to the plans in terms of cg and if it's too quick for you go longer lines. My modded PM with an OS LA15 flies beautifully on 55' lines, but I did sneak a little nose weight on to offset my aging reflexes (and nerve).

[Serge_Krauss]

Thanks, guys.