Exploring the "V" Wing

[L Edge]

Everybody knows this as a flying wing

What happens when we turn it?

Looks futuristic, but bending and torsion of the wings is a big problem.
Going to try and get it to fly.

Steps:

1) Wanted to get the CG right at location of the 64 EDF. Went thru a lot of cutting and tape like the x-24 until I had a gut feeling it's a go. Angle was 30 degrees(rear) and 43 degrees(front). Using EDF since prop would destroy model time and time again.

2) Installed a hollow carbon tube centerline down each wing. Starting from EDF, glued carbon strips on leading edge of wing, installed Depron endplate, continued carbon strip down to location of elevon, I glued carbon strips behind elevon cutout and installed elevon using masking tape on top and bottom. Did the same on other wing. To stiffen wings, used glue and epoxied 1/64 basswood at wing joint. Added rudder(depron) behind EDF.

3)Next, tried just chucking off a steep grass hill facing wind with just EDF and CG set. Went okay, after trim. Installed electronics, battery etc., to make flight worthy. Again(calm) and no EDF running, chucked and ok. Next, tried when wind was in the 3-5 mph and good results with tx. Now added the "stabilizer" and reset CG, tried chucking(calm) and then with 3-5 mph winds next day, same conditions.,OK.

4) To prevent violent movement of wings, going to run EDF at low speeds for testing. Had 110% focus on wingtips and had 10% EDF and chucked it. Elevons worked good and wing still stiff. Made it thru a number of trials increasing EDF by 5% and noticed an increasing " slop" in ailerons and some in elevators. That was just trying to keep the "V" straight. No turns. So what can you do to to control it.? A gyro, it's been done.

Will continue tommorrow.

 

[L Edge]

Reserved

 

[Foamforce]

Neat. What are your control surfaces? At first glance it looked like elevons, but are those additional servos out at the wing tips? Are you going to do ailerons and elevators instead of elevons because you need to keep pitch control at the very back (and therefore center), necessitating separate ailerons on the wing tips?

 

[L Edge]

Good eye @Foamforce. Knew I needed something to tighten up the slop of the controls so I came up with the idea of canards.

Have a 9 channel radio, I decided to set up 2 duplicate synced elevon controls in the radio. One set in the back and a set in front. Using the knowledge of flying a X-29, knew the canards on the wings will use very little movement to prevent excessive bending and torsion. I also knew that I need a trim mechanism for each of canards to fly straight and level.

For the back set of elevons beside syncing, knew the deflection would be the greater movement (20 degrees). So on the transmitter, decided to set the front canards(elevons) so that the travel height can be adjusted by the % dual rate and flatten by the exponential. That way, you can get the hopefully can get the correct deflection to match the back elevons. Since there is going to be more deflection on the ailerons then elevators, each is capable of setting the limits of travel.

Since the second set of elevons is assigned to aux 1 and aux 2, deflection of the servos controlled by reducing the end limit and I used 2 pots to trim if needed. Since there is no expo, plane has to fly like the old days before computer radios.

Time for testing:

1) Back to hill, (no wind) chucked about 1 ft off ground and finally got it near trim for flying straight. Moved up to about 2 ft in chucking and now for a attempted wide 90 degree turn(left). Wow, it went "every which way", glad I had expo in the front. Then went for the 90 degree right turn. Not bad.
2) Now, learning how to fly. Net result was 125% focus and be prepared to pulse opposite direction with stick immediately to prevent damage. I chose a slightly nose heavy CG to save plane. It was like learning how to fly all over with new rules of flight.
3) Now it was time for 3-5 mph winds. Moved chucking up to 5-6 ft high and released it. Not bad just going straight. Now for turns, plane was responsive indicating very little torsion or bending.
4) Went to club field so I can launch over 2 ft. weeds with EDF running. No wind, EDF 10%, launched at 6 ft and flew into weeds about 20 ft away. Good controls. Tried 20% EDF, 30%EDF , getting close to holding altitude, so went to 35% and moved from nose heavy to CG on target and it flew level and then went up to 20 and circled and landed after 3 min flight.
5)Moved to 40% and going good into the flight and all of a sudden in a shallow left turn I see the left wing lifting and twist and break off.

So, now you see why there are only a few "V" wing planes. Might work with a gyro, anybody going to try?