Like Crist mentioned, the profile event has been discussed at length as long as the forum has been around. The main sticking point is what constitutes a profile model. There have been no formal rules except for profile scale, and that is where some of the confusion starts and assumptions are made. The profile event was mainly started as a way to have another event to fly to hopefully attract more contestants to make a long drive to a contest. I don't ever remember there being skill classes in the midwest area, but generally, at first at least, it was the intermediate and advanced guys flying because they were most likely flying a profile model anyway and just needed one airplane for two classes.
As far as rules, that evolved to the regional thing as time went on. As technology improved, then things started to change. Much like the EZ-B class of indoor free flight, which was meant to be an entry level event for beginners but evolved into am expert only type event, guys started to really push the technology. At the SIG contest, they settled on a set of rules that a lot f clubs in the midwest used, including our club here in St. Louis. They are pretty simple and the name transitioned into the P-.40 event. The main requirement is the sidewinder mounted engine of no more than .40 displacement. They also added a no flap 10 point bonus rule to encourage everyone flying Goldberg models or Ringmasters and other Sterling designs with no flaps to enter. No pipes or Rabe style noses allowed, as one of the challenges to the event was getting a sidewinder set up t perform properly. There was never any fuselage thickness rule, as it was generally understood that the doubler and trippler nose blocks made for a stiffer nose and better engine run. That was really about it and in retrospect, makes for a pretty simple event that is almost like an IROC competition with out having to provide airplanes for everybody!
Some how along the way, the idea of how thick a fuselage is behind the wing trailing edge is what dictates a profile or not. I think the dimension of 3/4" was the deciding factor. I'm not sure if that is in the AMA scale description of not but I never saw that mentioned in anyone's contest announcement. It just makes the process of building a simple model more difficult and contrary to what was originally intended. I have always contended that what constitutes a profile model has been defined by the too many to be counted profile designs that have been published and the countless number of kits that have been produced in the last 60 or more . With the exception of the Rabe Mustunt series, I believe all have been a flat slab fuselage with a side winder engine. That is a precedent that can not be denied and is irrefutable. You can take these classic designs, and still do what is needed to make them lighter, stronger and stiffer to perform better and still keep their classic outline and look. Lots of newer designs have come along also to fit this same mold. The modifications and newer building techniques have gotten to the point where some say that if you are a beginner flyer, just build a full fuselage model, as it is just as fast and as some of these modern designs. In this day and age, using a solid plank fr a fuselage just eats up too much precious balsa that it just makes sense to use some different building techniques, and I'm all for that as long as the model still resembles the standard profile "profile!" Then the main deciding factor for a club is power plant size.
I am the evil doer that presented the idea of a 10 point penalty for electric powered profile models in our event. The main idea behind it is that I believe that electric models DO HAVE an advantage in this event in that there is no "sideways" way to mount the motor. The pilot doesn't have to deal with the set up of the engine and tank to get a good run. I'm not technically educated enough to try and figure out what would limit the motor and battery to equal a .40 size engine but that needs to be addressed also. In order to get around the 10 point penalty, all you need to do is have a no flap design for your airplane. This is all about trying to level the playing field and keep things simple and fun. I know there are guys out there that could design and build a profile model equal to what ever won the NATS or the last World Championships, but again, that is not what the event is all about, in my opinion.
As far as an internal push rod on a profile, that is nothing new and neither is a built up fuselage. The late John D'Ottavio published a model in American Aircraft Modeler that was designed for the AYSC event where a kid had to fly the same model in several different events. It is a very nice looking airplane and sort of looks like a mini JD Falcon and is called the "Topper." It's designed for a .35 engine, is a profile, and is classic legal and would fit your requirement for a "trifecta" airplane.
Type at you later and HAPPY THANKSGIVING!!
Dan McEntee
Topic: Profile Rules (Read 2946 times)