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General control line discussion => Open Forum => Topic started by: ash on January 23, 2013, 05:50:23 PM

Title: Rabe Bearcat III Power Options
Post by: ash on January 23, 2013, 05:50:23 PM
The Bearcat has been on my Wishlist since I was a kid and I got the plan and an NIB Enya 60-III lined up for it a few years ago. Just waiting for time and sufficient light balsa to present themselves....

Until last week, when a nice ST46 showed up in the engine arsenal.

If I remember correctly the original Bearcat was an ST46 powered machine - and I like the idea of the authenticity in a Classic ship. However, I suspect that combo would also be marginal on power unless everything was spot-on for light weight, prop choice and engine condition. I also suspect that Al might have gone for a 60 at the time if it was sufficiently proven. He did for the next design.


Good people of Stunt Hangar... do you think the used ST46 or the unused Enya 60-III is the way to go for a Bearcat III in Classic Stunt?
Title: Re: Rabe Bearcat III Power Options
Post by: Randy Cuberly on January 23, 2013, 06:16:34 PM
The Bearcat has been on my Wishlist since I was a kid and I got the plan and an NIB Enya 60-III lined up for it a few years ago. Just waiting for time and sufficient light balsa to present themselves....

Until last week, when a nice ST46 showed up in the engine arsenal.

If I remember correctly the original Bearcat was an ST46 powered machine - and I like the idea of the authenticity in a Classic ship. However, I suspect that combo would also be marginal on power unless everything was spot-on for light weight, prop choice and engine condition. I also suspect that Al might have gone for a 60 at the time if it was sufficiently proven. He did for the next design.


Good people of Stunt Hangar... do you think the used ST46 or the unused Enya 60-III is the way to go for a Bearcat III in Classic Stunt?

One thing to consider is that there are ST46's and there ST46's.  They are most definitely not all created equal.  I have three very special ones that rival the 60 for power and several more that don't even rival a LA46.
If you can get one built by one of the top specialists it will work very well in the Bearcat.  A stock one is not enough!
One other engine I would seriously consider is the Enya 50...very strong and would be a good match for the Bearcat.

Keith Trostle has a Classic Bearcat that was originally powered by an Aldrich 50 (powerhouse but not available anymore) and it worked very well.
It's now powered by a New Doublestar 60 (also not available to the common man but also a powerhouse).

Randy Cuberly
Title: Re: Rabe Bearcat III Power Options
Post by: MarcusCordeiro on January 23, 2013, 06:29:41 PM
Yeah Randy

There's nothing more different than two equal engines huh??

Marcus
Title: Re: Rabe Bearcat III Power Options
Post by: proparc on January 23, 2013, 07:45:11 PM
Adrian,
If the question is specifically between the ST46 and the Enya, then the Enya-no replacement for displacement. That said, the Evo 60 CL should get the job done for you with the aforementioned light weight wood.
Title: Re: Rabe Bearcat III Power Options
Post by: Mike Keville on January 23, 2013, 08:39:59 PM
. . . Keith Trostle has a Classic Bearcat that was originally powered by an Aldrich 50 (powerhouse but not available anymore) and it worked very well.
It's now powered by a New Doublestar 60 (also not available to the common man but also a powerhouse).

Randy Cuberly

Wasn't aware of the re-engineing (is that a word?).  Keith's Bearcat was for many years powered by a GMA-Jett .50....a real powerhouse.  I launched it many times - pulled like a horse!
Title: Re: Rabe Bearcat III Power Options
Post by: Balsa Butcher on January 24, 2013, 02:52:07 PM
Unless things have recently changed the Ro-Jett 50 is still available and is comparable to the Aldrich 50. If you want to put the ST-46 in a Bearcat, consider the Brodak Pat Johnston designed Bearcat. It would be a good choice for that model.  8)
Title: Re: Rabe Bearcat III Power Options
Post by: Randy Cuberly on January 24, 2013, 03:12:10 PM
Unless things have recently changed the Ro-Jett 50 is still available and is comparable to the Aldrich 50. If you want to put the ST-46 in a Bearcat, consider the Brodak Pat Johnston designed Bearcat. It would be a good choice for that model.  8)

Yes the RO Jett .51 is listed on thier website and should be a great choice for the Bearcat.  In fact it is mentioned that it had it's origin in the GMA Engines like Keith's Bearcat was powered by.

It is a Rear exhaust engine but is offered with a header muffler.

Randy Cuberly
Title: Re: Rabe Bearcat III Power Options
Post by: ash on January 24, 2013, 06:14:35 PM
Thanks guys - all signs point to grunt.

I've done a long list of models to build and nothing else on it suits the ST, so I might save it for a rainy day. For now I will resume saving up light wood for the Bearcat.
Title: Re: Rabe Bearcat III Power Options
Post by: EddyR on January 25, 2013, 12:29:14 PM
Ash  
  Let me give you my two cents worth of advice.   The ST/46 has plenty of power but is a poor choice for the Bearcat. I have a lot of experence with the ST/46 as I still use them in many planes. I have the early Rabe Bearcat,the same one as Keith. The ST/46 if converted to ABC will run the same flight after flight but with a 11/5 prop. The Bearcat needs a bigger prop because of the large frontal area of the body. For many years people used 12/6 props in large planes with the ST/46 and the rings wore out fast. Al Rabe had this problem. Brett Buck talkes about inconsidtant runs with them. Going to the 11/5 prop took care of that problem back in the early 1990's but the ABC conversion got rid of all the ring problems. But the motor works great with 11/5 props not 12/5 and never with a 13/5 and that is what I use on my Bearcat with a Double Star 60 motor in it. Also the 46 is to light with the short nose unless you build the tail super light. My Bearcat weighs 7 ounces more than Keiths and still flies quite well. The wing area is small and the larger motor will fly it better.  As a side note Dave Hemstrought   built a Rabe Mustang for classic and it flew well with a ST/46. He felt it needed more power and he told me he wished he had one of my ST/46 motors in it. I offered him one but he stopped flying the model. I never saw it again. Some one will pop up here and tell us how well the ST/46 motor turns a 12/6. Let them put it in a Bearcat and see how it works. The Broadack  Bearcat  might work well with a ST/46 in it. It has a thick wing and is  smaller than the Rabe Bearcat.
Ed
Title: Re: Rabe Bearcat III Power Options
Post by: proparc on January 25, 2013, 12:47:35 PM

Thanks guys - all signs point to grunt.


It almost always does!!
Title: Re: Rabe Bearcat III Power Options
Post by: ash on January 25, 2013, 03:29:39 PM
Ash   
  Let me give you my two cents worth of advice.   The ST/46 has plenty of power but is a poor choice for the Bearcat. I have a lot of experence with the ST/46 as I still use them in many planes. I have the early Rabe Bearcat,the same one as Keith. The ST/46 if converted to ABC will run the same flight after flight but with a 11/5 prop. The Bearcat needs a bigger prop because of the large frontal area of the body. For many years people used 12/6 props in large planes with the ST/46 and the rings wore out fast. Al Rabe had this problem. Brett Buck talkes about inconsidtant runs with them. Going to the 11/5 prop took care of that problem back in the early 1990's but the ABC conversion got rid of all the ring problems. But the motor works great with 11/5 props not 12/5 and never with a 13/5 and that is what I use on my Bearcat with a Double Star 60 motor in it. Also the 46 is to light with the short nose unless you build the tail super light. My Bearcat weighs 7 ounces more than Keiths and still flies quite well. The wing area is small and the larger motor will fly it better.  As a side not Dave Hemstrought   built a Rabe Mustang for classic and it flew well with a ST/46. He felt it neede more power and he told me he wished he had one of my ST/46 motors in it. I offered him one but he stopped flying the model. I never saw it again. Some one will pop up here and tell us how well the ST/46 motor turns a 12/6. Let them put it in a Bearcat and see how it works. The Broadack  Bearcat  might work well with a ST/46 in it. It has a thick wing and is  smaller than the Rabe Bearcat.
Ed

Thanks Ed, that confirms all my thinking on the matter. I had considered making a smaller Bearcat for the 46, but I've done that before and this time it's all or nothing - it has to be a Rabe Bearcat III or I'll never be happy. Your one looks great. As it happens I'm planning to use the inverse colour scheme to yours, the Beetlebomb - yellow with blue trim.

I might take the Enya into work today and get it fitted up with a venturi and NVA. I did the ST last night in preparation for sale.
Title: Re: Rabe Bearcat III Power Options
Post by: Randy Cuberly on January 25, 2013, 06:23:29 PM
Yes the RO Jett .51 is listed on thier website and should be a great choice for the Bearcat.  In fact it is mentioned that it had it's origin in the GMA Engines like Keith's Bearcat was powered by.

It is a Rear exhaust engine but is offered with a header muffler.

Randy Cuberly

I need to correct a statement I made earlier about Keith Trostle's Bearcat.  It does in fact have a different engine in it now than originally but it is not a Double Star 60.  It is a RO Jett GMA 51.  I was told earlier by someone that shall remain nameless (not Keith) that it was now a Double Star but that has proven to be not true.
I flew with Keith today and discussed it with him.
The engine is a powerhouse and runs very well with a large prop.

Randy Cuberly