This topic is the result of the "Tigercat" Subject. I really didn't find out anything new about this subject other than how crushing it is to build a twin and after months of building realizing just how futile it is to think you might be competitive. I knew the rules and built the plane accordingly to those rules and a few things came up. The rules for AMA carrier say in one sentence under scoring that you get 20 extra points if more than one engine is used to power the model, provided all engines contribute to the performance of the model from takeoff through at least the low-speed portion of the flight. Period... That's it? Their going to "give" you 20 extra points because you built this piece crap plane that you will never be able score high enough to win unless your the only one flying that day in the contest? Yes, I'm talking about competing to win not just flying for fun.
     I wonder if the Navy ever thought about this when asking Grumman to build a twin engine plane to add to the fleet? Yes we want this new twin engine plane to out perform all of the previous single engine planes and yes we want it to weigh no more the single engine planes in the fleet. I don't think so. So why if we want to build a twin for AMA carrier we have to build it to the single engine carrier planes weights? Oh yea we'll be given 20 extra points, that should level the field shouldn't it? Really? NOT. So what could we do to level the field or do we even care about that? I hope a few people will jump in here with a few ideas on how this might be done.

I started building a Fred Randell Tigercat for OS 25's.  I got about 60% done and put it aside.

Among other things, I didn't have a pair of engines that would throttle down well enough to justify going any farther.  Based on my experience with one engine, it needs to throttle down pretty low to get into a good low speed attitude.  I got the feeling that the way the OS's throttled-down, it would still be cruising around pretty fast at idle.  According the the rules, you lose for sure if one engine quits.

The only way to know for sure is to finish the plane, which would be big loss if it didn't work.

Randell's plane had two Johnson 35's (maybe 36) in the days of no engine limit, just the four pounds and 44".

     Wow Paul, sounds like Randell was my kind of guy. Course in those days the engines couldn't be throttled very well so that was a big problem. At least the engines were light compared to the high performance engine we have today (RC). Also I was thinking that the combined size of the engines might have to be limited to maybe 60 which would allow 2-28s. Oh, and I hope we are both talking about "Profile"?

     Bob, you say the rules are already skewed in favor of the twins, I hope you aren't referring to the 20 extra points they get? You mentioned Ray was using a 60 size(?) engine, are we talking CL-2 or Profile or was it the rules at that time? Although the plane I'm building is an electric I feel that my scores will be almost 100 points below the high score in AMA e-profile at this time. With the present rules for IC AMA Profile the engines would be limited to 2-18s or a 15 and a 21 and I don't think a plane with those size power plants would be competitive.

Obviously, electric is a whole, 'nother thing.  With no problem of an engine quitting, there is no reason to give a bonus.  Heck, put six of 'em on a plane.

I could sort of sense this was spinning to another electric break.

I tried to build a Sea Mosquito with 2 Webra 32 gts. With 2 fuel tanks, beefed up landing gear, I had about 2.5 ounces left to build a fuselage. End of project.
One big problem with a twin is that you lose 1/2 of your low speed points if one engine dies. You can easily lose the plane if the wrong engine dies.

The Randall Tigercat has a 34-1/2" span. The Sterling Guardian has a 36" span. The McCoy -60- weighs 15oz. A Fox Rocket .35 weighs 7-1/2 oz. A Fox .36X weighs 8 oz. I don't have a Johnson but figure it is on par with the Fox motors. The -60- swung a 10 x 8 prop and the smaller engines could probably swing a 9 x 7 or 9 x 7-1/2. Ray was not giving away anything. Randall built the Tigercat lightly but shows 7 oz wing weight on the plans. All of this tells me that under the scoring system in use at the time the Tigercat was a match with the single engine planes, or maybe even had an advantage. So far I am not aware of any similar data that applies today.

I'm still curious about the actual ratings of the single vs twin electrics.

     I don't understand what you mean by "actual ratings" for the twin verses the single in electric carrier.
     I concure totally about the twins verses single engine carrier planes in the early days of carrier competition trumping the singles. I also agree that they changed the outcome by changing the rules. I'm pretty sure those rule changes eliminated multi engine carrier from any chance of competing. From what has been said so far there is absolutely no chance that the twins will ever be allowed to compete because there would be a chance for them to win now and then so we will keep the rules as they are to make sure it is forever? I guess I'm having a hard time believing that I'm the only toad stule around that would like the twins to have a better chance at competing.

I'm not convinced that requiring a twin to have both engines running for the majority of the official flight was singularly responsible for making them uncompetitive. For one thing the Randall Tigercat is a complicated model to build as compared to the Sterling Guardian kit. The added complexity of controlling both engines was a liability. That and trying to get both engines running while under the clock. But mostly, the hope for twins faded as more powerful .65 engines entered the market. When Class I came into being the same issue existed. R/C Pylon Racing, and to a degree, C/L Rat Racing drove the development of the .40 engine and there weren't any smaller engines that could compete.

Electric is a whole new game. There are some neat airplanes from which to choose. The main issue for me is the lack of data on which to base an equivalency factor. It isn't in my nature to grab something out of thin air.

I seldom join in a thread I didn't start, that is not my job as the Carrier moderator.  What I would like to do though is to thank Eric for his fantastic notes and pictures of his F-7-F.  His comments on the unlikely competitive plane is what caught my eye.  I can't begin to tell you how many PM's I get about flying Carrier as if I were some kind of expert based on my just being here on this site.  The most asked question and comment is as follows, and I do edit it a bit for brevity.  "I would like to get into flying Navy Carrier, but I see no reason to do so because I am not a competitive flyer."  Note, no mention of any dislike about their conception of flying Carrier.  I think we all need to step back and realize how much the "Top End" of Carrier competition  is not what a lot of possible Carrier participants are interested in.
In asking what kind of CL flying these guys/gals are doing it generally appears that they are "sport" flyers and really don't think they want to go to a carrier meet with their beginner skills and compete against the "Pros"!  So, do they go to contests? Yes, but believe it or not their competition is generally in Beginner PA or intermediate classes here they are happy to just see how they are doing against guys much like themselves.
Now, after all that, I would suggest that what with the shrinking number of Carrier competitors, somebody someplace might try once again to set up a skill level Carrier ranking much like what saved PA from disappearing 30-40 years ago.
Two of us tried that suggestion several years ago when the NCS had roughly 100 members.  It was a popular idea that went no place. Perhaps this side of the CL hobby should take another look at what might just build contest entries and give a growth pattern to our hobby.
Again Eric, a most sincere THANK YOU  for your participation and skill.  To all that have such skills it might be time to try the above idea. Plesase, somebody start a new topic around what I have just offered and leave the Tigercat thread as is.
Joe
BTW I have two Carrier twins that are really fun to fly and play around with, a F-7-F and a Gruman "Skyrocket" (Not shown below)

     Joe, I'll get back to your post here soon. Bob, here are some of the stuff that I presently use. The Scorpion, and Hyperion's are no longer available, the cobra motor looks like it is on back order and may or may not be back. The ESCs are all available I think. Thing made in China are delivered in canisters or what ever and when those items are used up it becomes any ones guess as to whether those items will ever show up again. Some do, many don't. I indicated the things I look for in the items which is not much but it gets me started. There are so few people flying electric and information is hard to come by unless you meet someone at the flying field and that doesn't happen very often either. Bob Frogner helped me get started back around2000 I think and with out his directions I would have come along much slower. Please ask any questions you see fit, its the only information ever gets out. If I could get along with the chemicals involved in fuel proofing a plane I would be flying IC. I'll have to send one by its self as I've used up to much space.

     JOE, it looks like Bob has open a topic titled "Navy carrier skill level events" and I think it will work for addressing what you messaged about so see you over there.

     So anyway getting back to business here. To show you how brilliant I've become flying carrier I had forgotten that that AMA IC Profile could weigh up to 4 pds, I thought the limit was 3.5 pds like e-profile. So now I'm wishing the maximum weight for an e-twin motor profile could be 4pds so my F7 could score closer to 300 points. Oh well that's electric carrier. So now I'm thinking that in IC carrier if the rules would allow up to say 56 in combined engine displacement then it could be more competitive (2-28s). I just don't think it makes sense that the max displacement is held the same displacement as single engine carrier planes?

     So anyway getting back to business here. To show you how brilliant I've become flying carrier I had forgotten that that AMA IC Profile could weigh up to 4 pds, I thought the limit was 3.5 pds like e-profile. So now I'm wishing the maximum weight for an e-twin motor profile could be 4pds so my F7 could score closer to 300 points. Oh well that's electric carrier. So now I'm thinking that in IC carrier if the rules would allow up to say 56 in combined engine displacement then it could be more competitive (2-28s). I just don't think it makes sense that the max displacement is held the same displacement as single engine carrier planes?

Displacement equates to power, in simple terms. Performance in the event also equates to power. That's pretty much the logic. As we discussed previously, under the rules during the Classic Era the twin and single engined planes were pretty much equal on those terms.

As for now, that is something to consider.