Convert HobbyKing's X22 to RC electric

Build

HobbyKing's X22 chuck glider looks like a F22.
The wingspan is approximately 12".
Here's a photo with a 4.5" prop placed atop.

I sliced the fuselage to remove a section of the fuselage and to make a propeller slot.

The removed section is further sliced to form top and bottom slices. The bottom slice is glued back to the fuselage and the upper slice is fixed with a knuckle hinge and restrained by 2 wire hooks. Blenderm tape is applied to top of both horizontal stabilisers and then both elevators is shapened. Motor is screwed onto the 2mm ply firewall and the assembly glued into slots at the sides of the fuselage cutout. 2 rectangular holes are cut out from the sides for the 2 servos and the 2 servos are glued in placed by squeezing CA onto the mounting holes. The foam directly facing the rear of the propellor is carved to an angle to lessen the drag. Pushrods and runners, receiver, esc, 'velcro' are then glued in placed. So far, 1 afternoon.

The model is completed for test flights.

Tests

First Tests
1. Crash with left spiral.
2. Added 5 gm weight to back, but still crash in left spiral.

Second Tests
3. Total of 10 gm weight to back, carved the foam to rear of propellor. Exhibits more thrust, flew in left hand circles.
4. Doesn't like to turn right at all. At slow speed, moving stick right has the model continue drifting.

Third Tests
5. Taped port wing to reduce washout, readjust elevons. Now it can fly in left and right directions.
6. OK, getting used to the characteristics (limit). Nice power zoom, but not unlimited.

Fourth Tests
7. Steam warp the port wing to remove its washout, removed all 10 gm of weight, 'flatten' elevator. Flies ok, smooth flyer with a bit too much stability, doesn't roll axially and in high alpha attitude at slower speed.

Flying

Have had multiple flights.
Does not fly inverted, ran out of elevator.
Barrel rolls, non-axial even with maximum elevator throw in the inverted segment.
Large loops.
Clean stalls (relatively).
Occassional tail wagging, no more since removal of 10gm weight.

Crashes

A few tumbles and slam crashes. Have broke the nose in 3 places, the nose now has a hooked beak look. Discovered 2 metal screws concealed by rubber nose during one crash, have since removed.
Reinforced with flat carbon fibre flats to the 2 ends of propellor cutout, and at top and bottom of wing.
Weight is ca 100gm.

Plus and Minus points

Good size to put in motorcycle carrier box.
Fuselage cutout is quite cavernous for RC gear.
Flies level (nose up attitude) at about 50% throttle.
X22 weighs 38gm when new, quite heavy.
Washout incorporated at both wing tips for stable glides but it means tweaking is necessary for RC flights.
A guy at the field said he has bought one from HK to try.

Suggestions

• Move prop cutout rearwards slightly to have a more rearward CG
• Remove 2 screws concealed by the rubber nose to lighten nose
• Steam warp both washouts for faster flights (leave some on starboard wing).
• Make the elevons area bigger
• Instead of a pair of CF flats to each end of propeller cutout, maybe rearrange into T-section for stiffness.
• Insert knuckle pin hinge closer
• Trim the foam more drastically before assembly. The fuselage cutout, the angled foam rear of propeller (maybe make it to a point?).
• Draw the panel lines before assembly. Spray some colour.
• Try a different 6A ESC (current Turnigy 6A Plush)