No question or applicability to stunt here, but since I had the Phantom P30 apart, I thought you might find the guts of it interesting since it is so unusual.

 The engine was originally an Atwood design, but somewhere after Atwood quit, someone formed the "Phantom" company and continued making it. It is a "29", actually .298 to get just under the limit for class B. Ignition, of course, but this engine was later converted to glow (by someone who shall remain nameless aside from Richard Melvyn "Mel" Buck, my father, using a delicate technique involving a hammer to the timer case). It was reportedly used to set the last "B" Speed record that was below 100 mph, using a stripped-down hollow log P-51 Mustang kit and a 9-12 (!) prop. This was in Little Rock, Arkansas, at a flying site where Memorial stadium now sits, maybe in 1946-7. I say maybe and am equivocal because it appears to be one of those stories that got better over time.

   What I found interesting about this engine is the gas path. Basically, the gas comes from the crankshaft passage in to the crankcase, then travels through a hole in the side of the piston on either side into small "pockets" in the sides of the cylinder, then gets trapped there as the piston comes down. As the piston moves further down, the pockets are then uncovered by the piston and the charge wafts gently into the cylinder, where it is compressed and then ignited, then out the exhaust. The exhaust is two long narrow tubes brazed to the cylinder fore/aft. ALL of the charge comes through the holes in the sides of the piston.

    Several things about this - first, the dismally small size of the pockets severely limits the quantity of the charge and therefore the power. Unlike modern engines where the piston coming down forces the gas charge into the cylinder under some pressure and with some velocity, this one merely traps the charge under nearly no pressure. Nothing forces it into the cylinder, it just sort of drifts out. This is greatly inhibited by the exhaust gas left over from the previous stroke, where it would clearly just mix with it with no propensity to go up to the top of the cylinder and force out the exhaust. The result has to be absurdly dismal power, and extremely inefficient use of the charge. It had to be even worse on glow, where you need much more volume of fuel/air charge. I guess we know why you need a FOOT of pitch to go <100 mph, this guy was not going to spin very fast at all and had to have had power on the order of an TeeDee 049 at best (although at maybe 4000 rpm and a tenth of a horse or so, it was a fair bit of torque). That's actually reasonably consistent with a flight speed around 100 mph, presuming it was whipped heavily to get the prop unstalled - also as reported - it would have pretty decent prop efficiency at that low RPM.

    My Uncle Donnie cracked the piston in an attempt to "grow" it as mentioned in the other thread, so it's no longer runnable, so I can't check the performance at this point, but it had to be pretty sad, and getting 100 mph out of it was quite an accomplishment, if true. I know the airplane existed with this engine in it, since I have the pictures of it with my dad holding it.

    Here are some pictures of the cylinder, piston, and crankcase, so you can see what I am talking about.

   Brett

I'd suspect that porting is like a very crude Dooling system where all gas flow goes through the piston ports into the transfer bulge. The Dooling piston ports are still open to the bulge even at BDC and I'd be surprised if that P30 wasn't as well.

I'd suspect that porting is like a very crude Dooling system where all gas flow goes through the piston ports into the transfer bulge. The Dooling piston ports are still open to the bulge even at BDC and I'd be surprised if that P30 wasn't as well.

That's what it looks like to me.  To my calibrated eyeball, the spacing from the piston crown to the cutout reads as less than the height of the port (from honed cylinder to honed cylinder).  'course, my eyeballs haven't been sent in to the lab for calibration in quite a while, so I could be all wet.  Maybe we could put Brett up to sticking a ruler down that cylinder to see.

Too bad about the piston.

A truly ancient design.  Glad the designers have gotten better over the years.  Hard to imagine an engine like that pulling an Impact around.

Hi Andrew, I first obtained a P30 around 1954. It had powered a large low wing boxy airplane for a couple older cousins and they gave it to me after they had moved on to full size aviating. They had converted it to glow. I flew a number of different airplanes with it and I recall that it did well on an All Amerrican Sr.  I now have three P30s, one of each rendition. They run well on spark and will pull a surprising amount of prop at about 7500 rpm. On glow they like less diameter but pitch seems to remain about the same.
The first version (1941) has a single bolt on ex stack, the second version (1946) has two round stacks  on a bolt on die casting and the last vesion (1947) has the brazed on round stacks.  I think that the P30 is an interesting and unique engine in design as well as execution. I will run one on the test stand every now and then just for the sound and the wonder of seeing it pull as much prop as they will.

Brett  an old FORD camshaft would be a great piece to make a new piston for the P 30

Are you thinking it's a cast cylinder with a steel piston?

I'm looking at the cylinder and wondering if it's not machined, with some oddball stamping process to get the bulges.  The exhaust stacks could be brazed on -- their ends certainly look machined, and that says that they, at least, are probably steel.  And a close look at the crack on the piston sure makes me think that it's cast.

I think old Ford camshafts were steel, not cast iron.  But, I haven't played with them closely enough to know.

Are you thinking it's a cast cylinder with a steel piston?

I'm looking at the cylinder and wondering if it's not machined, with some oddball stamping process to get the bulges.  The exhaust stacks could be brazed on -- their ends certainly look machined, and that says that they, at least, are probably steel.  And a close look at the crack on the piston sure makes me think that it's cast.

I think old Ford camshafts were steel, not cast iron.  But, I haven't played with them closely enough to know.

The old ones I have are cast iron, and a good quality casting too.
Crankshafts were steel , maybe some camshafts but not the ones I have .
Most camshafts are cast from a high grade iron with a little chrome combined in the matrix, the chilled casting process makes a pretty hard and durable iron cam

Randy

The Madewell 49 has the same kind of bypasses with holes in the piston.  I think the same is true of the Vivell 35, but do not know for sure. The K&B 4011 has two holes in the piston and two in the liner to give more access to the bypass. I think, but don't recall for sure, that the K&B 61 has the same. 

My one engine hopup was of a K&B Series 75 35, for Midwest Sport Race. I made the airplane go ten miles an hour faster, from 90 MPH to 100 MPH.  The piston skirt at BDC was well below the lower edge of the liner, and so partially blocked the bypass entrance.  I cut a rectangular piece out of the piston skirt to remove the blockage.  Seemed to work OK.

My good friend Jim Lee flew a Humongous with a Madewell 49 for years with great success. I was always amazed at the power it put out. I had one in a dragon for a while, but after breaking two crankshafts I decided to give it up. Jim Lee never had a problem with shafts breaking as far as I know. I have had the best luck with Anderson Spitfires. They start easy, run well, and seem to last forever.

Andrew, I have lucked out flying old ignition engines in Old Time Stunt, and I would love to go up against Brett Buck flying in Old Time. I am sure he would win at that as well as he does in PA, but it sure would be fun.

I've never seen a Madewell or Vivell but I'd suspect their piston porting is the same as many other engines (for instance the early OS Max 15, many of the Enyas, K&B etc) where the piston porting was in addition to the normal transfer port that connects down into the crankcase. The reason for doing this was that it helped clear any mixture that tended to get trapped inside the piston but also helped cool the piston crown and lubricate the upper rod bush. It's an excellent feature and I don't know why it's been overlooked in modern Schneurle ported engines although there are a couple that use it but I think only in car engines.

One photo shows my Enya 60-IIIB with its matching piston and liner ports which of course has a normal transfer passage as well.
The other photo shows the transfer ports inside my Dooling 29 which have no direct connection to the crankcase itself as in the P30.

Hello Brett,
I would certainly hope that an LA46 would outperform a Madewell 49 anyday! If it didn't, then what have engine developers been doing this last 60 years? I agree entirely that something like an Orwick 64 would be an equivalent to an ST60 , but I am a bit puzzled by your statement about putting a vintage engine in a modern stunt plane. Who on earth would want to do that? The Madewell49 performs extremely well in a vintage style plane of moderate dimensions and weight. I have had no problems with Madewell 49s in such planes and I have seen others in the UK do exactly the same. Simply a matter of horses for courses. I enjoy the old stuff and I wouldn't want anyone to be put off giving it a try. Just don't expect modern plane or engine performance and enjoy the way it was! I get more fun doing this, than flying modern F2b  and enjoying yourself is what it should be all about. Each to their own, it would be boring if everyone flew the same sort of model!

Regards,

Andrew.

This is the Madewell 49, with the smaller Vivell 35 behind.  Note that the brazed-on bypass cover extends down to the crankcase flange, and the crankcase casting is "bulged" out at that point to match the bypass cover.  This indicates conventional bypass porting with a continuous passage from lower crankcase to the top of the bypass assembly.  Any "holes" in the piston would be unnecessary.

These are running engines in perfect condition, so I'm not going to take them apart to look inside!

Floyd

I would certainly hope that an LA46 would outperform a Madewell 49 anyday! If it didn't, then what have engine developers been doing this last 60 years? I agree entirely that something like an Orwick 64 would be an equivalent to an ST60 , but I am a bit puzzled by your statement about putting a vintage engine in a modern stunt plane. Who on earth would want to do that?

and previously:

The Madewell 49 is an excellent engine for stunt

   Lots of people are still asking about these sorts of ancient engines in real stunt planes, and for sport use. You see it here all the time, search for how many people want to know "which is better for a Ringmaster, a Fox or McCoy?" When the real answer is either one is terrible with respect to modern alternatives.

  Maybe you meant something different, but a Madewell 49 is not an excellent engine for stunt in the year 2013.

    Brett

Hello Brett,
I don't know if we are talking about the same thing here. A lot of people in UK fly vintage style planes from the late 40s and very early 50s. There is also a desire to use authentic engines. A Madewell 49 Is an excellent choice for one of these designs that are medium size (for the period) and reasonably lightweight (as were most deigns of the period, some even stick and tissue!)
  I don't know what condition the Madewell 49 was in, that you mention. If you have a Madewell 49 that isn't seriously worn, then you will have a good combination. I fly and have flown large period stunters with spark ignition 60 power (Super Cyclone, Anderson Spitfire, Orwick 64 etc, even a McCoy 60 on sparks). I find the smaller, Madewell powered planes to give little away to the larger 60 powered sparkies. I can only surmise that the Madewell in question was seriously down on power!

Regards,

Andrew.

Hi Brett,
             are those holes shown in the piston pic for the wrist pin or are they part of the transfer port system?

My bet is on the later.

Hello All,
A very interesting post and even if it has strayed off topic in parts, still food for thought. If you want to fly old planes with period sparkies then there are plenty of 60 sized engines of good power. Lots of exotic stuff that is valuable and may not escape from the glass case! The OK Super 60 is a very cheap and quite powerful engine that is readily available at a low price, quite the other end of the scale!
  However, when you go below 60 size, the number of engines powerful enough to fly stunt is not really that great. The Atwood Triumph on sparks is good, as is the McCoy 49 and 29 again on sparks. I hesitate to mention the Madewell 49 as Brett doesn't rate it, although I have had success if flying them! I wouldn't rate it against the previously mentioned sub 60 engines, although a competent performer in my experience.
  What else is there in the sub 60 category that people have had success with? I have flown Bullet 29s and if you build light then there is the Bantam and the bigger Arden. I then start to really struggle. I have lots of sparkies in the sub 60 size, but few of them develop enough power for old style stunt.
  So has anyone got experience of the smaller spark ignition engines that are OK for stunt. Let us leave out the expensive rareties, mainstream engines that don't cost a fortune?

Regards,

Andrew.

I've accumulated a selection of ignition engines, and I've run most of them on the test stand and a few in planes.  The big plus for the larger engines is that the ignition system (batteries & coil) remain a constant weight, regardless if the engine is a 19 or a 60, and larger planes can typically carry more weight without a penalty.  However I prefer smaller planes most of the time, so I've tried to find small engines that work well.  I've got a couple O&R .23 side ports, and while they start very easily, and run consistently, I don't expect they'd be a really good match on a CL stunter.  I would think a Fireball built and flown for fun would be about their limit.  Jim Kraft runs one on a radio assist, old time free flight plane that's always fun to watch, and it works well most of the time.  I built a Vampire a few years ago for an O&R .33 redhead, the engine ran fine on the bench, and on the plane it started ok and ran alright but it was never consistent and it was very light on power.  The plane flies considerably better on an ignition Mohawk .29, the cheaper generic version of the OK .29.  The actual OK .29 might run better yet, but it's heavier since it has a crank bushing, and the plane is already nose heavy.  I've got a Vivell .35 that starts and runs pretty good on the bench, but I wouldn't build a plane for it, again because it seems very down on power.  In my estimation, I'd say the Vivell puts out about as much raw power as a worn out McCoy redhead .19 on glow.  I'd like to try an ignition Forster .29 or .35, but of the three glow Forsters in my collection, only the .29 really runs very well.  The front rotary ignition Forsters seem to sell high too.

In the bigger 60's, I was really impressed with my OK Super .60 on the bench, for as little as they bring on Ebay I didn't expect easy starts and fair power.  The Anderson Spitfire is the engine I run most, set up as close as I could to Jim Kraft's, and it flies my Humongous with plenty of reserve power.  Aside from a faulty coil or two, and one user error event it's run very well. 

In general, a larger problem than finding a small ignition engine that runs well might be finding a small OTS plane fit for a small ignition engine.  While there are plenty of 60 size stunters from the ignition era, most of the smaller planes are more for sport.

Thanks guys!
I had forgotten about the Forsters and the De Longs. No excuses, as I have several of both, just too many engines I suppose! I have tried most of the O&R engines in the sub 60 size. I think they are fairly pathetic in output and wear very radpidly when used for stunt. Fine for free flight though, where the run times are low.
I am glad that someone else thinks the OK Super 60 is a good stunt engine. I have several and none have cost me more than $70. An absolute steal in my opinion. I am told that a well known US modeller gave the Super 60 a really bad name, stating that he had maybe 6 of them and couldn't start a single one! Whoever he was, thanks for saying that, seems to have kept the price down if nothing else.

Regards,

Andrew.

Hello Floyd,
Thanks for thinking of the Vivell 35. I was a touch bothered about mentioning it in view of Brett's dimissal of the Madewell 49. As far as I know the engines are very similar. The crank case was modified to make the Madewell 49, with an enlarged cylinder to go with the modded case.
I have several of the Vivell 35s of differing marks and  differing conditions. I must admit I like them, very pleasant on the eye and a good one is quite powerful. I would be interested in what yours can do on a 10x6. I never made any notes when I was running them. I think they have more than enough power for say a 40 inch span stunter.
I would run the best of mine, but we have a sudden cold snap here in the UK and I don't fancy messing about outside, until the weather warms up.

Thanks,

Andrew.

Thanks for thinking of the Vivell 35. I was a touch bothered about mentioning it in view of Brett's dimissal of the Madewell 49.

  Sorry, that was not my intent. But I still see people trying to use vintage engines in stunt competition all the time, and I wanted to make sure that there was no misunderstanding about how effective they are compared to current engines. "Vintage" includes almost any baffle-piston engines up to the ST46 - these are just not a good solution for current stunt competition. You can use them, and some people would have success, but up against a field of any one of dozens of current engines they will be severely lacking. I know I am queuing up 10 people to say it doesn't matter and <<insert stunt hero of your choice>> could win with anything, but that doesn't change the argument.
 
   This is related to (actually, the flip side of the same coin as)  my argument on Classic- building an airplane from 1969 and then putting an Aero-Tiger in it yields profoundly different performance than you would have had originally. Swell, no doubt the airplane is a lot more pleasant to fly, but any other purist argument about it pretty much goes out the window.

    I find this era of engine design interesting but aside from niche applications they are no longer competitive. I just hate to see people continuing to thrash around with Fox/McCoy/Supertigre/etc when you can get an LA46 in two days for under $100. If that's what people want to use, certainly no skin off my nose but if they want to win contests in the year 2013 they are creating a pretty tough challenge for themselves.  

   Brett

Hello Brett,
I couldn't agree more with you. I can't see anyone using a spark ignition old timer engine in a modern stunt contest. Doesn't make any sense at all, to do such a thing. There are quite a few people that enjoy the challenge of running spark ignition, vintage engines in period control line models and this is the area that I am referring to. I don't know about your VSC in the US, I thought there was a section there where such outlandish things were done! Over her in UK and Europe, most old time enthusiasts fly free flight, with just a small number of heretics running old design control line models on spark. I suspect that this is growing in popularity as I keep hearing of more and more folk tackling vintage sparkers for C/L. Rest assured that your PA and Rojetts will not be disturbed by noisy old sparkies!

     You'd be surprised. I still get the occasional question about how to modify a 40VF to "do a good stunt run", meaning, run like a Fox 35. Or talk about how "complicated" pipes or Uniflow tanks are. In this case I am not even limiting it to sparkies, it applies about the same to a ST46.

  There are still many people who are trying to learn to be competitive using ancient technology and ideas. Maybe you can learn something trying to make it work, and that is valuable even if difficult. But it's certainly the hard way to go.

   Brett

Hi Brett, just curious, how many classes/places did an LA.46 win at the 2012 nats?

Hey Big Bear, mebbe ya got a lose nut on the handle?   

A loose screw, a loose nut, which ever causes the worst effect on the model flying! LOL!!

BIG Bear
RNMM/AMM

  I am never disappointed, as predictable as a sunrise...

Hi Brett, just curious, how many classes/places did an LA.46 win at the 2012 nats?

    In real stunt, 0. Just like the ST46. And Fox 35. And McCoy 35. And Madewell 49. And for that matter, just like a RO-Jett 61. Does that make them all equally desirable for stunt?

   Brett

 I am never disappointed, as predictable as a sunrise...

    In real stunt, 0. Just like the ST46. And Fox 35. And McCoy 35. And Madewell 49. And for that matter, just like a RO-Jett 61. Does that make them all equally desirable for stunt?

   Brett

Thanks Brett, I just wondered............  BTW, would you ever part with the P30 , or is the sentimental value too great?

Regards, Phil Bare

As promised, here is the Vivell 35 running.  It tachs 9470 with a Rev Up 11-4 wood.  It does 9150 on a B-Y&O 10-6.

Fuel is Coleman lantern fuel with 25% Castrol SAE70 m/c oil

In terms of "propwash", it seems to have lots more thrust with the 11" prop

That's not bad performance for a '40s engine.  It probably would do a bit better on glo, but I didn't try glo.

Floyd

I start it with the spark timer fully advanced.  It doesn't kick back.  F.C.