RCP F18 V3M Ready to fly :)

Hi everyone -

With a couple days of bad weather keeping me indoors, I have been very busy the last two days and finished up my modified RCP F18 V3.

I will eventually do a more detailed walkaround video after I maiden the plane and start the dialing in process.  I have a paint job in mind, but since this is a test bed and I will probably be trimming some bits off the trailing edge of the KF airfoils, I decided to go with just some magic marker on the canopy and "nozzles" and some painter's tape on the wing tips to help with tracking and orientation.  Although very simple, I have found with testing the NAMC Mig-35 and Mig-FA that this is a very effective scheme to help me keep track of the plane in just about any sky condition.

So after all the hacking and slashing, I ended up with these dimensions

• I shortened the plane by 2.1", my plane is 42.25" long, the stock build is 44.35" long.  I am hoping this will make the plane more responsive overall, but especially in the pitch axis as it is now more "compact";
• My AUW with a 2200 3S battery is 599 gr/21.1 oz which is a good weight for this plane.  I didn't change the wing area, so wing loading should still be fine.

With moving the motor 1" forward, I have moved the stock CG back by 1" just as a starting point, here is a picture of what my electronics bay looks like with the battery placed to balance on this new CG.  Obviously I will only find the true CG once I have had a chance to fly and adjust it for balance and KF dimensions.  In this picture if you look on the right hand side, the black "+" indicates the new CG I will start with.  I made several little plus signs aft of that in 1/4" increments to give me an idea of how much I am moving it as I dial in the plane.  I am assuming it will only be going back as from my previous V3 experience, the plane balanced nose heavy on stock CG.

I placed my rudder servos a bit farther back that I normally would like, but since I will more than likely be trimming some foam off the back of the KF airfoils as I dial in the plane, I figured it would be easier with them out of the way.  I still need to trim off the extra pushrod that is sticking so far forward.

When I measure from the front of the battery to the tip of the bullet nut on the motor mount which in previous testing I referred to as the PMI (polar moment of inertia), I get 12.5" which is a huge improvement in tightening this up and hopefully making the plane even more responsive, precise and maneuverable.  With the old setup, my battery was all the way up against the bulkhead which gave me a stock built PMI of 18".  Big difference.

Here is a side shot, it does look like a much different plane than the stock, I can notice the 2" less in length.  I shortened the nose by about 5/8", but I think it still looks pretty good, not as "pointy", but that is a purely aesthetic thing for my preference.  

If using the length of the plane as a percentage, with the new length and motor location, the motor is located at 61% from the nose which is almost identical to where it is on the NAMC Mig-35.  Again, I'm hoping getting the CG, CT and CM closer together I will be getting better balance and overall performance.  

Above and below you can see that I mounted my servos and ran my pushrods externally as I like to do on all my planes, I find it makes for much easier, more secure installation and adjustment and keeps the prop wash area clean of as few obstructions as possible.

So I am very excited not only to have an F18 in my "hangar" again, but to start some testing and comparison side by side with the NAMC Mig-35 to see if some of the principles built into the Mig-35 carry over to the F18 which is a very different airframe style with a more straight wing.  Let the field testing begin!

Cheers,

Scott