Build and Learn

The hobby of RC Flying has many avenues that can be explored, and those avenues have their own cross streets and intersections that turn off from them making the hobby an ever growing and learning experience. From an educators perspective learning is an ongoing experience and for me building planes created and designed by others is a passion that I enjoy. The best part is every build is different and unique and the results are often never the same.

Recently, I revisited one of my favorite community based groups MESArc (mesarc.club). This organizations is a school based program lead by a wonderful educator, Jake Marshall, who inspires, and teaches children to be creative while learning how to make and fly RC planes, etc. I decided to try one of their first released projects, the F-22. For those of you that are advid admirers of jets you will know that this machine has a signature look and amazing flight characteristics.

MESArc's version looks great and adapts inexpesive parts into the design to bring together a plane that is simple enough to build, fly, and in the event of a crash, rebuild without much of a loss.

Pictures of my build process are as follows:

As with all my projects, I review several times before commiting, and with this project I was in love with the looks and simplicity of the build process but changes did need to be made. I am not a fan of the flat wing design, so naturally I felt the need for an airfoil. My go-to airfoils are the Arminwing: a scale looking and functional design that provides lift with speed, and the Kfm airfoil: a simple airfoil that has many versions for the use of application.

Being a jet (like) plane I went with simplicity and modified the wing into a Kfm2 airfoil. This wing of choice is very stable under fast and slow speeds, provides lift, and increases the core strength of the foam board without the need of additional spars. The result was unchanging to the overal apperance of the plane. The leading edges are now rounded and there is a step ontop of the wings. The core strength of the wings were increased and the weight of the plane increased slightly.When building I also tend to notice points of weakness. For this build it is how the wings are joined to the fuselage. The wings are seperate by design and are joined by two narrow edges; one from the top plate and the other from the belly pan. The result is a plane that has poor wing loading strength as tested by holding the completed plane by wing tips. This incresead the potential of folding the wings should a high G manuever be performed, and ultimately destroying the plane. To address this problem I would look to join the wings in the center with a tape and glue joint, or make the wings a one piece with the tail sections separate, taped and glued together. If you follow the club (MESArc.club) the MF-35 is an example of a strong wing design with a one piece bottom wing and the horizontal stabs taped and glued on. Also, the use of a carbon fiber spar or an inexpensive wooden dowel that ran from wing to wing foward of the motor placement would add additional strength as well. Again, be creative and check your work for points of weakness.

As you can see the build went well and the plane looked good, but was it functional, and how long would the design hold up? Foam board is very inexpensive and for a good reason, it is made from CHEAP material. It is up to the designers and builders to strengthen and reinforce the board for a solid build.

This plane, is sleek, and steath looking but the elements of design do not reinforce the board. The maiden and second flight of the plane went well and recieved many complements however, as expected the wings folded on the third flight and destroyed the plane. 

I can't say that I was upset, as much as I was disappointed, however the experience gained was priceless.

So what was learned from this? Inspect your build as you go along and should you come to a head and notice design flaws which affect the strength of the plane, STOP!!!  Address the problem immediately. The designers put the plans together and out there to share with the community but the real responsibility is in the hands of the builders and pilots. Also, share your findings with the designers and the community. Build, Learn, Grow. 

Hope you enjoyed the review. Please post your comments and share your thoughts.