Rubber Powered Airplane - SO trial event

[calgoddard]

There will be a new rubber powered airplane trial event at the 2017 SoCal SO State competition that will be held at the California Institute of Technology (Caltech) in Pasadena, California on April 8, 2017.

The rules can be found here:

http://www.socalstatescioly.org/downloa ... planeC.pdf

Basically any rubber powered airplane that weighs a minimum of 5 grams will be legal as long as it fits within a "Large FedEx box." The interior dimensions of that box are publicized as being 12 3/8 inches x 3 inches x 17 1/2 inches.

Too many Wright Stuff (WS) competitions involve 90 - 95% cookie cutter kit airplanes. There are no restrictions in these trial event rules on configuration of the airplane. It can be a bi-plane, a canard, a pusher, a twin, etc. There are no restrictions on the prop diameter. There are no restrictions on the rubber motor weight.

The requirements for the flight log have been relaxed from those of many WS years.

Another goal of the trial event rules is to ease the check-in burden on the Event Supervisor and the parent volunteers. No more weighing of rubber motors. No more measuring of wing span, wing chord, stab span, stab chord, and prop diameter. No more risk of damage to models due to handling by parent volunteers and awkward use of calipers. No more student airplanes that don't meet all the dimension requirements (well at least if the students had the common sense see if their airplane fits inside a large FedEx box).

Let the students figure out the optimum motor weight for their air frame and prop.

The FedEx box can be obtained free (no charge) at thousands of FedEx locations across the United States. They can also serve as convenient and inexpensive transport boxes.

Very few models will fly longer than two minutes in a typical HS gym under these proposed rules.

I hope that some students have time to build a new airplane and fly it in the reserved Caltech gym. I understand that the peak flyable height there is about 36 feet.

[chalker]

There will be a new rubber powered airplane trial event at the 2017 SoCal SO State competition that will be held at the California Institute of Technology (Caltech) in Pasadena, California on April 8, 2017.

The rules can be found here:

http://www.socalstatescioly.org/downloa ... planeC.pdf

Basically any rubber powered airplane that weighs a minimum of 5 grams will be legal as long as it fits within a "Large FedEx box." The interior dimensions of that box are publicized as being 12 3/8 inches x 3 inches x 17 1/2 inches.

Too many Wright Stuff (WS) competitions involve 90 - 95% cookie cutter kit airplanes. There are no restrictions in these trial event rules on configuration of the airplane. It can be a bi-plane, a canard, a pusher, a twin, etc. There are no restrictions on the prop diameter. There are no restrictions on the rubber motor weight.

The requirements for the flight log have been relaxed from those of many WS years.

Another goal of the trial event rules is to ease the check-in burden on the Event Supervisor and the parent volunteers. No more weighing of rubber motors. No more measuring of wing span, wing chord, stab span, stab chord, and prop diameter. No more risk of damage to models due to handling by parent volunteers and awkward use of calipers. No more student airplanes that don't meet all the dimension requirements (well at least if the students had the common sense see if their airplane fits inside a large FedEx box).

Let the students figure out the optimum motor weight for their air frame and prop.

The FedEx box can be obtained free (no charge) at thousands of FedEx locations across the United States. They can also serve as convenient and inexpensive transport boxes.

Very few models will fly longer than two minutes in a typical HS gym under these proposed rules.

I hope that some students have time to build a new airplane and fly it in the reserved Caltech gym. I understand that the peak flyable height there is about 36 feet.

Glad to hear you have taken interest in rule writing. A couple comments based upon my years of experience with the rules creation process:

-One concern you expressed is that 90-95% of planes are "cookie cutter" designs. How do these rules changes prevent that from still occurring? I'd propose that there are very few competitors that look at the current rules and say to themselves "gee, if only the dimensions are more lax, I'd be able to experiment, but I guess I'll have to use a standard design". Most of them use these designs because they are proven, relatively inexpensive, and provide a low barrier to entry, and somebody will come up very quickly with an 'optimal' design / kit for this event.

-How are you going to change the challenge from year to year? One of the reasons we proscribe dimensions is because it allows obvious changes from year to year. If you don't make such changes, competitors will reuse devices and designs, giving those that competed in previous years huge advantages over those just starting this year.

[calgoddard]

Including the 2005 season, the WS rules have always placed too many design restrictions on the airplanes. Why require them to be monoplanes? Why place precise maximum limits on the span and chord of the wing and stab? Why limit the prop diameter? If the goal was to prevent long flights, this is much easier to accomplish with an overall size restriction and minimum weight of the model without stifling creativity. At our regional WS competition there are often 80+ teams and it is too time consuming and too risky to measure five or six parameters of each model.

The trial event rules for the Rubber Powered Airplane event .are not intended to prevent kits from being commercialized. Kits are useful because they provide viable airplanes to fly in the event. Kits are very helpful for novices and beneficial for the casual competitor. But why handcuff the future Burt Rutan?

I doubt someone will quickly come up with the optimal design for an airplane that meets the Rubber Powered Airplane rules. It might be competitive, but not the best design.

I submit the following example as anecdotal evidence. The F1G outdoor rubber powered free flight event has been around since 1938 and is still popular today. The rules of this international event are simple - 70 gram minimum air frame and 10 gram maximum rubber motor. Yet the configuration of competitive F1G models has evolved significantly over the years and continues to evolve to this day.

The minimum airplane weight and/or the size of the box specified in the Rubber Powered Airplane event can be changed from year to year to prevent the same models from being flown in different seasons. The FedEx large box was chosen because it has a uniform and reasonable size, it is free, and it is readily available.

The Rubber Powered Airplane event could be re-named Wright Stuff - to preserve that traditional SO moniker.

[jander14indoor]

While I don't see the difficulties in checking planes that you do, variations on the rule theme are good to vary the challenge to the students.

A couple of specific comments on your proposal.

Why did you simplify the flight log by taking away the unspecified parameters? This is science and engineering, taking data is critical. Figuring out what kind of data is useful is a valuable skill. That's why we originally added the free parameters. It doesn't take but seconds to determine if there are six instead of three parameters.

Warning about using a commercial product for the rules. Inspection equipment should not depend on things outside the control of the event supervisor. At any point Fedex can change their boxes, change the tolerances, or may not have them identical across the country. The controlling rule should be dimensions of the boxes, NOT a commercial product they may be based on.

Jeff Anderson
Livonia, MI

[calgoddard]

The flight log requirements were simplified to ease the check-in process. I have spent a considerable amount of time at a WS check-in table determining whether the 3 mandatory and 3 optional parameters were satisfied. I have also spent too time instructing parent volunteers how to determine whether a flight log is satisfactory. Even then, time and time again, I have had to resolve whether something listed on a student's flight log is a required parameter, an optional parameter, or neither. Query, does a series of column entries that reads, for example, "Rubber Motor No. 1, Rubber Motor No. 2, Rubber Motor No. 3", etc. qualify as an optional parameter?

In the very unlikely event that FedEx changes the dimensions of its Large box, after the SO rules are printed, a rule clarification published on the SO Nationals web page could easily address the issue. FedEx sorting facilities are highly automated and this militates against changing the dimensions of its standard boxes. It is simply not realistic to believe that FedEx will discontinue using some form of Large box or that it will use dissimilar sizes of its Large box in different parts of the United States. Finally, the interior dimensions of the measuring box have been publicized in the rules of the Rubber Powered Airplane trial event. In the worst case scenario any reasonably competent ES could quickly build a suitably sized box for measuring the size of the airplanes at check-in.

[jander14indoor]

You may be overthinking the optional parameters. The whole point is it can be ANY thing the student choses. So check for the three required parameters, and count three of anything on the flights.

Jeff Anderson
Livonia, MI

[chalker]

I also suspect you are overthinking the verification of dimensions under the current rules. Most event supervisors I've seen utilize pre-fab templates that make it very easy and quick to verify each of the parameters. The students just hold the template up to their plane (or vice versa) and see if it fits.

Regardless, the use of a Fed-ex box is a unique idea and one we should definitively discuss more amongst the rules committee.

[Cammaster]

So how is this NOT like Wright Stuff?

[bjt4888]

Calgoddard,

I like the idea. Possible creative variations/design elements that I can think of would include: biplane, large stab area (possibly a tandem), larger propellers, large wing chord and stab chord, etc. Lots of elements to expirement with.

Brian T

[wlsguy]

I also suspect you are overthinking the verification of dimensions under the current rules. Most event supervisors I've seen utilize pre-fab templates that make it very easy and quick to verify each of the parameters. The students just hold the template up to their plane (or vice versa) and see if it fits.

Regardless, the use of a Fed-ex box is a unique idea and one we should definitively discuss more amongst the rules committee.

I would agree the use of a Fed-Ex box is an interesting idea to make measurements easier. The 5 dimensions are possible with a template but seem excessive. The weight measurements of the plane and each motor (typically 6 or more at many competitions) takes significant time. Additionally the event supervisor must keep the motors and watch each team to be sure they don't switch out to a different (heavier) motor.
The proposed rules would eliminate many of these concerns.