still4given

Hi Guys,

I mentioned it in another thread but I thought I would give it it's own thread.

We are holding an RCPRO Warbird race on the 19th of this month in Apple Valley at the VVRCF field. It's right on the way to Rabbit Lake for those who haven't been there. you can find the rules at
http://www dot rcpro dot org/html/rules/warbird_racing/warbird_racing_rules dot htm

It is open to all AMA pilots. We run three classes, Bronze, Silver and Gold. Trophies for the first three places in each class.
Two pole 700' course. $20 entry, $10 for additional classes.

If you have a fast warbird come and race with us. If you just want to watch some really fast warbirds, come on out to field on the 19th. Registration starts at 7:30 and racing will begin at 8:30.

See you there!

Blessings, Terry

Yellowsierra02

Hey Terry did you get my PM about your Jett .50 and YS 1.10?

Thanks

Justin

still4given

Hi Justin,

I did get you PM and have responded to it. The Jett 50 and the YS 1.10 are very different animals. My Jett 50 is really on step right now but in the Phoenix Strega, the YS 1.10 has the edge. Top end may be close but that 4 stroke on high nitro pulls like a horse through the turns. On something smaller and cleaner, it may be closer in speed.

Blessings, Terry

bob27s

My Feedback: (19)

Boy those are two very different animals to compair........ the YS110 put out power more along the lines of the Jett 100L and 90L engines... it just runs in a very different torque/rpm range. There is rarely any substitute for cubic inches... especially fuel injected/charged cubic inches.

still4given

Hi Bob, I agree. In our warbird racing, the Gold Class is almost 100% YS 1.10's. However, the fastest plane at the last event was a J3 cub with a Nelson 40 in it. Justin had asked me about how the two compare, but more so how the 1.10 and the 60XL compared. I haven't even seen a 60XL yet so I couldn't say. I have to assume it is faster than my SJ50.

Our rules give a pretty good advantage to the 4 strokes. 4 strokes can be twice the displacement as 2 strokes. That was probably close a few years ago before the advent of the YS 4 strokes, but not today.

See the chart below

bob27s

My Feedback: (19)

Yeah, given the rules the YS110 is a no-brainer.

The SJ-60LX is not that much more power than the SJ-50. Its the same small block, just a few more rpm.

However he 60LX does put out the same sort of power/rpm on the 8.8x9 racing prop as the racing .40 engine.

With the rules, a Nelson or Jett 428 engine would probably be the best bet.

Rules allow great variation in the airframes... seems to me a well built Stilleto withe FIRE 50 it would certainly keep up with the big blocks.

(and I wish I had my old ME109.....)

MJD

My Feedback: (1)

I assume the Nelson .40 was not one of the engine options listed on the box..

still4given

A Nelson 40 is a 40. There are no rules limiting what brand of engine you can use. You can fly it on any qualifying 400 square inch airplane. The cub in question had what looked to be a Q500 wing with rounded wing tips and about a 25 size fuse. It was about a minute and a half of knife-edge flight. Tony, the pilot, was flying a World Models p51 with a screaming YS 1.10 in his first few heats until he planted it in anticipation of the upcoming harvest. He flew the cub in that last heat and broke out with a 1:26 I think. It was very impressive to watch and hear.[X(]

The essence of our rules are to allow folks a pretty wide birth as to what equipment they select with the limiting factor being the breakout times.

Gold Class > 1;30
Silver Class > 2:00
Bronze Class > 2:30

You can find all of the rules at RCPRO dot ORG under Warbird Racing.

It really is a lot of fun and the planes look great!

Blessings, Terry

z06kal

I wonder when they are going to start allowing for electric setups in these planes. You can limit power output by wattage. Just run up every power system through a watt meter during tech. Figure out a competative wattage to displacement comparison and call it a day. Plenty of ways to make it fair and fun for all. Time to adapt to new trends as it is hard enough to fill these events.

still4given

This has been suggested a few times. They may at some point develop an electric division but I doubt they will ever have them racing side by side with the nitro planes. Just too different.

I'm not sure how hard it is to fill the events. This is only our second go around so I can't yet tell. I really like this format. Pretty much anyone who can fly reasonably well and enjoys speed competitions can enjoy this. The planes look great racing around the two pole course and is maybe more enjoyable to watch than three pole course.

I'm all for there being and electric division but I personally am not interested. I love the challenge of making nitro engine driven planes go fast and turn left.

IMO it would be more difficult fill and event with electric driven warbirds.

Blessings, Terry

z06kal

Terry, what is so different? Just a different way of spinning the same prop. I used to race Q500 and deff miss it. The power plant should not matter. JUst make sure the planes are more or less the same speed and just have fun racing.

Yellowsierra02

I would almost think the electrics would have a disadvantage. With Electric you have a battery and the longer you race the less power you have. With the gas plane your getting faster because you losing fuel(getting lighter). I guess it would come down to picking the right battery pack. You would want the lightest pack that would keep the power up intill the end of the race.

z06kal

Yes that would be the case but with 90 second races not really much of an issue with any of the new stuff. The electric planes will be a little heavier but they also have cleaner aero. If you properly measure every setup's power draw you will have a far more consistant line up. I personally think the current glow rules they are using are completely nuts. You have guys with Nelsons and pipes competing with box stock cheapy chinese motors? Even when you try to bracket them up into classes you will have large discrepencies in performance which really takes away from the true spirit of racing IMHO. Also the airframe rules seem really open to interpretation.

bob27s

My Feedback: (19)

Huge differences actually.

<soapbox>

An engine is phycially/mechnically limited in performance and power output due to physics, its moving parts and design. Just as an airframe has its design limits of performance. An engine creates its own heat energy from fuel through chemical and physical reactions. An engine converts much of that heat energy to mechanical energy, and must disipate the heat energy that is not converted in some other fashion. An engine also converts some of the energy from fuel into sound energy. That must be taken into account too. The mechanical motion of many moving parts requires lubrication, and proper combustion of the fuel requires an exacting mix of fuel and air.

An engine must breath air as part of its fuel. So an engine powered airplane must have provisions to provide air and fuel to the engine, must provide for or accomodate the exhaust products and sound energy produced, and must provide for cooling for the extra heat energy that is produced. The airframe must accomodate engine mounting (accomodate vibration, torque, energy transfer, rapid accelerations), must accomodate the size,shape, and frontal area of the engine cylinder(s) and a carburator. Must also accomodate linkages, fuel tank, fuel lines, and of course a prop & spinner.

Yes. Very complex. Very involved. Quite a challenge at times.

An electric motor is generally a rotational shaft with the only moving parts being the bearings (in some cases the bearings so not move). Lubrication is not an active system. Motors in general are cylindrical in shape, much more like a turbine than a recipricating engine. An electric system functions by converting energy store in a battery. That engergy is converted from fuel, by an engine, located somewhere else. The capcity of the battery determines the amount of stored energy that can be delivered, and how fast that energy is delivered over a period of time is the power the system can produce. It also then defines the endurance of the system. Delivery of the power is limited only by the capability/materials of the motor and electronics to withstand the huge energy flow. The process of transfering the energy (current/voltage) can and does produce heat that must be disipated. Thus some cooling of the motor, windings, wiring and battery is required in flight.

An electric airframe design is in direct contrast to a piston powered aircraft design. Heat that must be removed is not heat created, but is that which is lost through a transfer process, thus cooling inlets/area are limited in requirements. The motor requires no air otherwise to operate. The battery requires no air otherwise to operate. The motor is small in size and small in frontal area, and can by in large can be accomodated entirely within a typical airframe structure. The motor does not create significant sound or vibration energy. Most sound or vibration comes from balance and prop/air noise. Thus no muffler or exhaust system need be accomdated.

In my opinion an electric motor installation is far simpler to create, accomodate, install and use than any possible type of engine installation. Fewer structural requirements. It takes full advantage of the fact that the device used to generate the energy being used is not flying on the airplane.

If a comparison could be drawn as a reference... lets look at Reno unlimited air racing. Turbines do not compete against piston power. Turbines are more like electric. Simple in design, limited in some respect by materials but otherwise are low drag, high output, easy to operate, little to no vibration. Trying to compete piston complexity against turbine simplicity does not make for any sort of competition - its a mismatch. Their association has held the line, and Unlimited remains a recipricating engine, prop driven event. In contrast, Unlimited hydroplane racing saw that changeover about 20 years ago. Running a turbine powered boat was mindless compared to the expesnes and hassle of tweeking a merlin or allison all day (all year?) long. The total switch did not take long. But that change fundimentally changed the event. So much so that I suggest that it destroyed the event, and took the sanctioning body down with it. (you can look up the history.. will not detail here).

Do electric motors have there place on aircraft? Yes. Do engines have there place? Yes.

Should they compete head-to-head? I say no.

The model air racing competition (event, rules) discussed here includes the complexity, variability and mechanical nature of the engine. The engine is 1/3 of the equation. It takes time and effort to address that component from its many requirements and aspects. Take away that complexity and it is not the same event.

An electric power event has many merrits. Electric can indeed be quicker, cleaner, quieter, and may indeed be cost effective. But for racing, it represents a completely different event. Perhaps it may lead to better racing since the focus then can be placed on the other 2/3 of the equation, which are the airframe and most importantly the pilot.

Other aspects of the hobby such as helicopters and pattern competition have seen this mix occur in competition. How that works out over time for the stability, consistantcy and nature of events has yet to be seen.

For me, models and r/c aircraft have always been about the engines. They always will be most important.

</soapbox>

z06kal

Hey bob, very lengthy post! I think it is pretty obvious that they are different means to the same end. I would not however compare them to a turbine using jet propulsion. I am also not suggesting that there be mixed pylon racing in a very strict, and well designed, legacy racing event such as Q40, Q500 etc where rules are very specific in leveling the playing field. But in very open ended events like this war bird event I really don't see what the big deal is. You have a VERY open to interprention requirement of airframes and a very very very open engine class. The fact that you had the fastest guy running a Nelson .40 in a cub against other scale war birds using sports motors is plenty proof of that. Might as well throw electrics into the mix at that point.

still4given

No matter how you twist it. Electric power is not the same as glow power. Tweaking those little Internal combustion engines so they are at their best is half the fun. Go down to your local drag strip and see how many electric cars you see. It's all about the engines. That cub I told you about is and anomaly. They came about a few years ago when SWRA told everyone that they would have to start running mufflers on their 4 strokes. A few guys got together and came up with these cubs as kind of a protest. For the most part you will see a lot of YS 1.10s/.91s in Gold and then OS/TT 61s in Silver. Mostly 46-55 in Bronze. However, the rules are such that you are free to experiment and look for something different if you like. I'm running right now two YS 1.10s, a Jett 50, YS 45 and TT46Pro. All of them are very competitive and well matched to the plane they are in.

Blessings, Terry