RC helicopter doing impossible aerobatics?

Not totally sure, and I could be totally wrong but I'll give you my guess.

If you look at the cross section of a real helicopter's main rotors, they are very similar to the cross section of a commercial fixed wing aircraft - the top and bottom of the wing both curve the same way. That's because a real heli needs to stay upright most of the time so it only generates lift when basically upright.

On the r/c heli, the main rotor's cross section is horizontally symmetrical - the top curves up and the bottom curves down. It is still thicker in the leading edge than the trailing edge, but it's the same shape on the top half as the bottom. This allows it to generate lift no matter which way it's flying. Other than gravity, the r/c heli doesn't really know or care which way is up. It just flies whichever way it's commanded because it generates lift in any direction.

Others, please correct me if i'm wrong.

 

When flying a model helicopter like that, you use a mode on the transmitter that allows you to have full power at both ends of the pitch curve i.e. full positive pitch and full negative pitch. With everything being symmetrical, the helicopter doesn't really care which side is up and will do whatever your reflexes are fast enough to make it do.

 

They got gyros and this and that to help the rc heli able to fly these attitudes. A real helicopter can't perform those stunts. It's not so much power to weight ratio because many rc helicopters that can perform "3d" flying are similar to those that can't.

 

They got gyros and this and that, all this makes the rc heli able to fly these attitudes. A real helicopter can't perform those stunts. It's not so much power to weight ration because many rc helicopters that can perform "3d" flying are similar to those that can't.

 

It's CGI guys...

 

That looks totally FAKE to me.

Jedi

 

Believe it or not, there's no CGI or even video editing tricks here!

Alan Szabo is one of the best model helicopter pilots in the world. He is known for his ability to push the limits of a helicopter and show his extreme finesse performing maneuvers at low altitude.

Search his name on Youtube and continue to be amazed! The guy really is that good......

FWIW, someone also asked "is this the new super motor?" at the start and the battery pack looked *huge* to me - So, I don't think it's an "off the shelf" T-Rex 600 however.

Note also that these guys have been flying inverted and doing stuff the real ones won't do for years and years - Watched a guy, upside down, touch the center of the rotor head to a nail on many occasions. "Tail stands" and other strange stuff is now SOP at the world championships.

Cheers,
Ian

 

When I starting flying helicopters in '93 I decided to also get into rc helicopters too and back then guys were already doing this and had some locations to stay in for summer camps for people to learn this type of flying. Only thing is that back then I didn't see so many maneuvers and I bet is because of the vast improvements on the avionics and gyros.

 

Indeed.

I'm out of touch, but suspect they basically disable the gyro when doing this crazy stuff - They'd just be fighting it all the time - It wants to "stabilize" the thing, which is the last thing they want!

IMO, the biggest change has been Li-Po batteries and "super" brushless motors - Back in the day, you needed a big nitro 2-stroke to do the 3D stuff - Now it can be done with electrics - As demo'd above.....

Cheers,
Ian
PS - Another name to search out on YT if interested is Curtis Youngblood - Multi time WC.

 

Impressive! I always felt that R/C helicopters were better performers than their fixed-wing counterparts, and this helps confirm that.

I'll bet that there are some full-size helo pilots who wish they could do stunts like that!

 

You mean full-sized counterparts, right?....

But yes, RC versions have been going inverted etc for many years - IIRC, the British Army has a helo display team that can do it *briefly*. Read somewhere that they too practice and do "proof of concept" tests using RC.

+1 I think the problem is they'd fall apart and/or the rotorhead/rotors would "explode".

Cheers,
Ian

 

th535 got it right.
When flying in "3D mode" like this one the blades are spinning at a constant speed (VERY fast), and the left controller thumb-stick at middle position generates no lift. When the Heli is right-side up, pushing the left stick 'up' will keep her airborne (or SHOOTING straight up, or sideways if that's the heli's orientation, at the stick extant due to an insane power/weight ratio).

The right stick also controls servos connected to the swashplate, but instead of acting collectively to alter the pitch constantly around the blade's arc they 'tilt' swashplate (i.e. cyclic control), affecting only pitch or roll. Pushing the right stick either forward/back or left/right while at the same time reversing the left stick from forward of center to back of center, will reverse the main blades' thrust 'upwards'. Voila, the heli is now hovering upside down.
This video from a simulator is nothing compared to Alan Szabo's flights, but give you an idea what's going on with the sticks during acro flying:
[ame]http://www.youtube.com/watch?v=Z1C-6l3xe2Q[/ame]

My RC helis are all "fixed pitch" which means the left stick controls motor speed only (basically I have a twist-throttle like a real heli, but no collective lever so I can't control the blades' pitch for fast "punch outs". If I want to climb, I have to wait for the motor to accelerate the blades, which really isn't that long a wait). FP helis are much simpler to fly but you can't go inverted, which is fine with me since my brain and thumbs aren't fast enough for fancy 3D

Just watch what Alan's thumbs are doing during a "typical" routine. Insane!
[ame]http://www.youtube.com/watch?v=p3nNiUStTE0[/ame]

By the way, the video you posted is 3 years old. The latest 3D helis are even more insane....
[ame]http://www.youtube.com/watch?v=kst_dKT1SyI[/ame]

IMO cheap little FP heli are still incredible fun. Even a relatively minor crash with one of the big CP helis will almost always require $100+ in parts to get back in the air.
I've got at least 100 crashes on this little guy, and have spent less than $40 on replacement parts:
[ame]http://www.youtube.com/watch?v=M4e1gNrKoOo[/ame]



Here's a typical "Collective Pitch" heli's swashplate and servo arrangement.
"Collective" inputs with the left stick control all three servos simultaneously (just like the collective lever in a real heli), while the right stick moves the servos independently (just like the main control stick) so the swash plate tilts, changing the pitch and/or roll. Moving the left stick left and right controls the tail rotor pitch, just like foot pedals.
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impressed as well...wow... one step short of "FM" (f'nmagic)

it's all about thrust and the vectors, it is one thing to generate the correct vectors, it's another to change them at the rates being demo'd

there must be some sort of sensor that always keeps the thrust directed against gravity...
leaving the pilot to fly the maneuvers and amount of power used... don't think it could be done without some sort of help

 

Nope, except for a tail-lock gyro (which only keeps the heading i.e. yaw fixed until the pilot tells the heli to "spin") all sensors are in the pilots brain. The latest technology does greatly help in stabilizing the heli, but like someone else said these aggressive 3D choppers need to be inherently unstable (like an acrobatic plane) to pull of such quick maneuvers.
The transmitter is also a computer, so you can pre-set "mixes" and servo "dual rates" for affecting how the servos and speed controller act for a given input, but as for collective and tail control that's all pilot.

Flying at this level requires an immense amount of hand-eye coordination, reflexes, and PRACTICE both on simulators and real life. The top guys basically do it full time, sponsored by manufacturers.

 

Here's a good video of Red Bull's acrobatic full-size heli explaining the basics of control.
I don't believe that this can maintain sustained inverted flight (I'd guess due to airframe stresses involved), but can still do amazing, very un-helicopter like stuff: [ame]http://www.youtube.com/watch?v=GLf4WUnIW4Y&feature=fvst[/ame]

[ame]http://www.youtube.com/watch?v=0-9Ror7rrlg[/ame]

Lucky golfer goes for a ride!
[ame]http://www.youtube.com/watch?v=I7G_hRiqSpg[/ame]

 

extremely gifted pilot- respect!

 

Helicopters are incredibly fun and any flight is a thrill, but is too bad they can't sustain inverted flight, and that would also require a committed pilot with some balls. My main instructor made an ex military pilot throw up because he got too nervous while performing maneuvers that didn't include anything inverted!

 

At my old R/C club there were a couple of guys that were really good with a helicopter. They would fly inverted and do a lot of aerobatics. I didn't have patience when trying to learn on a helicopter and stuck to planes.

 

Mr. Szabo has competition...

Check out this vid of Tareq Alsaadi piloting a huge gas powered heli around palm trees. Needless to say if those blades ever met human flesh it would be very messy.

The fun really starts around 1:30:

http://www.youtube.com/watch?feature=player_embedded&v=5bSERka3dU4

Here he is actually cutting the grass at ~3:00, 4:15, and digging a hole at 4:37:

http://youtu.be/YIOwHURs4-I?t=2m50s

 

I have one of those little eFlites. They are amazing for the money.

No gravity sensors, just lots of practice.

I saw a photo of a guy who had been hit in the face with a large RC helicopter blade. It was gruesome. Very serious injuries.

 

No, I meant fixed-wing R/C planes.

 

There are even cheaper 4-channel FP micro-helis out there now, like this one:http://www.xheli.com/27h-9958-miniheli-red.html

Most are copies of the Blade MSR. Even though it's 1.5yrs old I still think Blades (MSR is now discontinued, replaced by the hot-rod, flybarless MSRX, but the larger 120SR is what I fly mostly these days) are worth ~double the price. They're just smoother and more precise to fly, my local hobby stores stock spares, plus even though the helis are made in China Horizon Hobby is US based and they have GREAT (again US based) customer support.

I got a nice bruise on my finger from the little 120SR. A strike from anything 250-sized or above (the pros in the videos earlier are flying 600+ size helis with 4.5' diameter blades spinning at 2000+rpm) would require an emergency room visit, if you're VERY lucky only for stitches!