Buttered Cat

How do you control collective pitch?

With fixed pitch the throttle stick controls the head speed, but with CP how do you control head speed AND pitch?

(I did say it was a beginner’s question!)

x-planes

My Feedback: (2)

The pitch is one channel and the throttle is a different channel.
Most flying is done with a throttle hold switch and pitch is controlled by the throttle stick.
So the throttle runs at full the whole time while you have constant controll of pitch.
What kind of radio do you have?What kind of heli?

Buttered Cat

Thanks for that. It is as I suspected.

Radio is Futaba FF7super. No CP heli yet. I’m just thinking ahead. I’ve been having fun with a Hirobo FP tethered, and now thinking about the next heli.

jh4db536

My Feedback: (2)

in CP the throtle is usually in a constant "cruise control" mode called governor mode which is controlled by the ESC. it keeps the motor spinning at a target speed set by the curve. therefore the rotor is spinning at the same speed regardless of the load theoretically.

both channels are controlled by the same stick however the CURVES is what makes that possible.

the blade pitch controls up or down. so when you land or take off, youre doing it at max rpm basically. landing at high RPM means the helicopter is pretty stable during landing and getting into hover as you have a gyroscopic effect to make it stable which is very noticable in high headspeed helis like the trex and x400. i believe this is one of the key factors that makes them fly like a 30sized nitro.

Dezynco

I went through the same thing as you. What you have to do is have 2 settings in your transmitter (assuming that you have a computer transmitter with heli mode). One setting, "normal", is for spooling up the rotor blades. Then you'll flip a switch on your transmitter (mode 2) that disengages the throttle from the left stick, letting the stick become collective pitch only.

However, you should leave the throttle and pitch connected as a beginner - that's what I'm doing for now. Use your radio to program throttle and pitch so that you have slightly negative pitch (or no pitch) until you reach half stick, at which time the rotor is at about maximum speed. Then you ease the stick up a little more to lift off. This will allow you to cut the throttle in a panic situation! Don't cut the throttle while the heli is in the air though, only after it's on the ground.....

Later you can experiment with Normal and Mode 2 settings. If you do not have a computer radio, you can connect throttle from the speed controller and the pitch servo with a "Y" cable, but you should put a computer radio on the wish list!

Good Luck!

Buttered Cat

Dezynco are you sure setting up two modes is really necessary? I do have a computer transmitter but not with heli mode. Your second suggestion of leaving the throttle and pitch connected makes sense to me (for those ‘panic’ situations), but if I were to separate throttle from pitch then why not run the throttle from, say, the flap channel on my transmitter?

Dezynco

Because God only gave us two arms! This is the way it is done...no need to reinvent the wheel. Later, you'll use one of your knobs to fine tune the throttle and one to fine tune your pitch (if you ever get into glow engine heli's). Might be necessary for days when humidity and temp are weirding out the engine....probably never need them for electric powered heli's (aint it great!) For now you'll have your hands full just trying to control the thing, without having to find a knob on the transmitter and without taking your eyes off the heli.

jh4db536

My Feedback: (2)

DUDE!

there's no need to control the throtle seperately. BASICALLY your throtle is either ON or OFF. ANYTHING over zero stick tells the esc to startup/spool up the motor which probably takes about 5 seconds. Zero stick is to shutdown accordingly. if you have idleup mode on then the motor shouldnt shutdown at any stick position. the GOVERNOR mode controls the throtle for you. the only 3 things you control is the throtle curve which finetunes the governor's target rpm, startup, and shutdown. basically the left stick is all pitch.

other throtle buttons on the Tx might include motorshutoff &/or throtle Hold for autorotations, etc

Dezynco

Right! Like jh4db536 said, no need to control throttle after the rotors spool up, you will only be changing pitch with the left stick - anything above center is "positive" pitch, which makes you lift off. The rotors should be at or near full speed around center stick. You'll program that into your transmitter with throttle and pitch curves.

Later, if you want to "3D" you'll need negative pitch for inverted flight, at which time you'll disconnect the throttle from collective by switching modes on your transmitter. But that will be WAY down the road! The last thing you need is to be looking for the mode switch or some knob while your helicopter flops around on the ground, tearing itself to pieces. Not a pretty sight! (Ask me how I know!)