Epic Flying with a Tilt Rotor RC Jet

After the previous build article, the Tilt Rotor Jet has been tested and, man, this thing is impressive!

Thrust vectoring on RC airplanes is famously tricky to get right. That being said, this project seems to prove that it doesn't always have to be that difficult. This plane, built in collaboration with YouTuber Tom Stanton, features two rotating motors on a tilting aluminum spar at the front of the aircraft. They work together to give the aircraft thrust vectoring in the pitch axis. 

We hoped to test:

• If the plane would actually fly in this configuration
• The crazy aerobatic ability of the aircraft with thrust vectoring 
• Setting up 'flaps' for slow flying and hovering (with a headwind)
• VTOL capability 

With this brief, all we had to do was chuck it into the air and get flying!

Test Flight Video

You can watch the full flight video here. 

Flying with exaggerated pitch control

The first flight of an airplane is always a little nervewracking. What if all of your time, effort and money goes to waste? Thankfully, the plane performed just fine. It was a little aggressive on the roll axis, wobbling side to side, but I managed to keep it under control and climb out to a safe altitude where I could get a feel for the aircraft. 

With trimming done, it was time to see what the Delta Jet could do. As predicted, with the thrust vectoring turned on, the aerobatic ability of the airplane was fantastic! It could maneuver in a very tight space. Differential thrust programmed to the motors allowed even more control.

As we had the thrust vectoring toggleable, with the tilt channel programmed to a switch on my Spektrum DX9, we could assess the difference of each mode. With the motors locked in place, the pitch control was extremely limited. This is probably because the aircraft had no canards to share lift at the front of the aircraft. With the motors in tilt mode, the variable thrust could be used to pitch the nose up rapidly with a simple blast on the throttle. This was especially helpful on landing!

Switching it up with flap modes

After ticking two tests off our list, it was time to do some more programming on the radio to see if we could set up some different flight modes involving flaps. These combined the angles of the elevons and motors. Tom and I used a three position switch to toggle three different flight modes. These were:

1) Standard, with a neutral angle on the elevons and motors

2) Mid, with an angle of about 20 degrees on the elevons and motors

3) High, with an angle of about 45 degrees on the elevons and motors

In all, these different modes would hopefully allow the aircraft to fly much slower without assuming a high alpha attitude. This is where the airplane lifts its nose high up and forces the air downwards with its wing to create the lift necessary for slow flight. The problem with using motors instead of canards to do this surrounds the throttle setting.

With too much throttle in the high mode, the aircraft would pitch up uncontrollably resulting in a sudden backflip. Although this looked cool, it wasn't the intended outcome! After learning how to control the aircraft better, both Tom and I realized that in high mode the pitch should be controlled only by adjusting the throttle, not the elevator. This was difficult to get our heads around.

Going all out

With the initial flight tests out of the way, it was time to really pour on the beans and go for it. In a straight line, running a 4s 1500mah battery with two race spec quad motors, the 800g plane could get up to some respectable jet-like speeds. 

It really was impressive how easy it was to stop the aircraft dead in its tracks with a sharp tug on the elevator. You could pull the nose up and then blip the throttle of half a second to get the whole thing to flip on the spot. Impressive stuff. 

Closing thoughts

To see what happened in the end, you'll have to watch the flight video! Safe to say that this aircraft delivered some excellent performance and satisfied both of our expectations:

• The plane did fly
• The aerobatic capabilities of the aircraft were outstanding
• The flaps worked to an extent, although the 'mid' mode was far easier to control than the 'high' setting
• The aircraft could take off from its tail and achieve some level of VTOL capability

So, all-in-all, this was a great project. It was lots of fun working with Tom. If you liked this article, there will be more one-off projects like this here on flitetest.com very soon, so keep a look out for them appearing on the site.

Make sure you check out Tom Stanton's YouTube channel for more projects like this in the future. 

Article by James Whomsley

Editor of FliteTest.com

Contact: james@flitetest.com

YouTube Channel: www.youtube.com/projectairaviation