Do we really have control over the headspeed we run ???

First let me say I do not wish in any way to cause any arguments in this thread it is only my observation and logical thinking.

Headspeed is set by 3 factors, these are in no special order

1. engine tuning
2. Blade pitch
3. Throttle amount

First the engine should be tuned correctly so this removes tuning from the equation,
Blade pitch according to everything printed everywhere should be between 4 and 5 degerees
Last there is throttle amount which printed everywhere should be 50% (regardless of the stick position used)

So really there are no variables, and if these basic conditions which are what are printed and given as examples everywhere are used then the headspeed is not actually chosen by the pilot it is controled by other things such as the blades used, model weight, engine power output and many other characteristis.

If the engine is tuned to perfection then the only other things a pilot can change are the amount of throtle used and the blade pitch, A little less pitch combined with a little more throttle give a higher headspeed (which is how we all set up the speed we want), BUT this is then changing the basic setup which is the printed guide.
The same goes for a lower headspeed is created by lower throttle and greater pitch , again this is altering the basic setup instructions and guides printed.

The reason for this post is I recently bought a tach and decided to check the headspeed I was running on my raptor, (which runs very well and does everything that my flying ability allows).
I have the heli set up in normal mode for -4 to +9 linear pitch and -9 to +9 in idle up (which is a pretty standard setup) with headpeeds of what I liked (done by sound and how the heli feels on the controls).

What surprised me was with flying I obviously altered the pitch and throttle curves to keep speeds constant but never actually checked the resulting curves with a pitch gauge to find out what they ended up being. This was done after using the tach and finding I was running approx 1800 and 1600 rpm headspeed in idle up and normal modes respectively, to my amazement the resulting pitch for idle up was only 3 degrees in the hover position running in idle up (1800 rpm)

So in answer to my question is yes!! we do have control over the heli headspeed but ONLY if we do NOT follow any guide to the letter on setup of pitch and throttle curves. If however we do follow guides of 50% throttle +5 degrees pitch and a well tuned engine the these parameters are what dictate the resulting headspeed and the pilot has no control over what the resulting headspeed is untill they fine tune the pitch and throttle curves.

Again I will say I wish no arguments to come from this I just thought it was worth a mention.

can you glow guys change any gearing? headspeed and gearing plays a HUGE factor in micro electric helis. moving to a different pinion size, even if only 1 tooth, can have a drastic affect on the entire heli.

I will be watching this thread.

Since when has anyone ever followed the instuctions anyway

Instructions are only there to give you a guide on getting started.
Due to the fact that everyone lives at differing elevations, temps, ect and may be using different engines and varying nitro persentages of fuel you can only use the figures in the manual as a rough guide at best anyhow.

We have total control over our head speeds with just a few clicks on the controler I can go from around 1600 rpm to 1800 rpm

You can have absolute control of headspeed with a governor. The governor does whatever it has to do with the throttle to maintain the set head speed.

headspeed : the rate of rotation when a cute chick walks by.

Do we have control?-Yes.

To change the head speed you simply change the throttle curve for a given pitch angle, so say at hover point instead of 50% you have 40%. We have complete control over the head speed. I run 1400 in normal mode and 1810 in idle up, both rpms were chosen by me, not the model After all, that's why we have pitch and throttle curves.

Colin

Hehe after all the answers everyone did come to the same answer as I originally said, which was an answer of yes we have control over our headspeed as long as we deviate from the original guides that are printed everywhere.
The whole reason for this post was for nothing more than my own personal amusement what I was actually hoping for was a post from someone who had used the guides that are given as examples everywhere and actually are running the headspeed that the guides had suggested would result from the given settings.
as an example the raptor 30 manual shows a guide that gives a normal headspeed of around 1550 (if i remember correctly ) for normal mode and 1800 for idle up, which is what i used as a starting point when i first built the heli, the settings were then altered over time until I achieved the speed that I was advised to run by a good pilot. In the end I spent some time playing with the idle up2 setting just to see what speeds were actually achieves using the settings in the manual and found them to not even be close to what the manual said they would be.

In reality the whole experiment i did including this post only shows just how valuable it is to have a good pilot to help when a novice is learning how to setup a heli, my own experience did show me that learning to fly the heli ( which is a achievement in itself) is not as hard as getting the heli set up correctly in the first place. A well set up heli is easier to fly yet if the pilot can't fly it they can't set it up.

thx all for the spending the time to make comments

Well i'll throw in my thoughts here head speed vs mortor rpm.
I agree with the perfect tuning of a motor and any good pilot out there knows it is either good or bad there is no inbetween with a helie engine, becauase either you are flying or your just bearly hold your bird at a good hover or a littel fat and no power to pull.
This is a constant for us all, but in 3d and F3C you need to have a constant head speed not the rpm of the motor we are talkng about the speed of the blades, and regardless of the rpm the head speed will change so if your in a tail slide a aileron standing or static roll your baldes catch more air or speed up with less resistance and when this happens the copter becomes different each time you do the stunt or or even a fast inverted fly by. And you lose the feeling of your bird so each time it might be alittel more or less rpm and you might drop or even shoot up because you react to the rpm and give more only because you hear it drop.
A Governor feels the speed of the balde and reacts before the rpm drops to keep the head speed up or down, we react to the engine sound bogging or changing rpm sound, not all the time you can hear the speed of the bades when you are doing high flying. And mostly the hight of the aircraft is very inportant to F3C pilots because we have a box or a line we need to be exact or loose a point or 0 out for stunt.
If your just having fun with your buds showing off or enjoying forward flight or a inverted hover governor is not needed your reacting to your flight with the only thing in mind not to crash but take it to the edge and have fun and to be honest I felt it was a expence I didn't need till I tried a fellow pilots bird with one and there is a marked differance and a more control and more confortable feeling and smooth transsition between monuvers.
So if this makes any sence, if you want the perfect roll or Cuban 8 Yeap or inverted 200 foot drop to a revers at 10 to 15 foot for a landing or a long tial slide you bet you need it.
Fun fly and doing your stuff high or on the edge of loseing control like a chaos move that looks so cool no you don't need it your just having fun and your enjoying the bird and not trying to keep it in a perfect box then nope save your money for that expensive fuel and baldes.
Jerry

You will have to forgive me a lot here for my apparent ignorance, but I was under the impression that a governer does infact react to the speed of the engine as (again only an assumption) it uses a magnet atached to the fan and a sensor to count revs. If this is the case then it is looking at engine revs not blade speed then changing the throttle amount to compensate and keep the speed the same under all loads.

I have no experience with a governer at all other than reading mags and sites so I cannot in any way give a real oppinion as to how good or bad they are or even how they actually work.

The governor like the gv-1 has to have the gear ratio put into it. Then it easily can compute the headspeed.

You hit the nail right on the head with that one!!!!!!

I'm completely with you Jerry!!

In fact the rotor speed change in respect of the load that it has, so because the rotor is loaded differently if you are just hovering or stopping a fast dive with a fast climb after it, the speed cannot be maintained constant just using a throttle/pitch curve.
A governor is a must IMO, yes you can use throttle/pitch curve to adjust the speed of the rotor in many situations, but not in all af them.
Why real heli does have a governor?? learn from full size!!

Gianluca

POWER/LOAD=RPM. POWER=RPM * TORQUE. LOAD=DRAG ... varying due to rotor angle of attack (pitch angle).

Guides are for getting your heli in the air. What happens after that is up to the heli owner. All manufacturers give settings that will nominally get your heli flying.

Regardless of the settings you choose, everything still has to obey the laws of physics. IE you have to produce a force equal to and opposite of the affects of gravity in order to hover. You can set the variables anywhere you want but to maintain hover, the final physics equation must be balanced or it won't hover. Operating a Heli is a precise balancing act done with high energy variables.

So when you say a pilot has no control over the settings ... that's like saying the pilot has no control over changing the laws of physics. In that sense ... yes we are all confined to the rules of physics (or at least the result of physics equations). Fortunately, these "rules" have lots of variables that can be manipulated as long as the final equation comes out balanced. A heli is probably the best device to make use of the most variables all at the same time.

Good Luck,
d.tipton

The Gv-1 only needs the gear ratio to let you set it by head speed vice a little math whereas the revlock you tell it what RPM to hold the engine at, the resulting head speed you have to figure out for yourself.
For example I know my OS 50 produces max HP at 17000 rpm, and I know my raptor has an 8.5:1 gear ratio so 17000/8.5 = 2000 rpm head speed.

If I want to run 1950 instead of 2000 I have to tell my revlock to hold the engine to 16575 rpm 1950x8.5=16575 or take the closest setting that it supports to that rpm figure.

So yes a governor senses engine rpm by a fan mounted magnet and controls the throttle servo to maintain that rpm. How you set up each one differs slightly. Its notable that a governor only can control head speed within its capability, you can still bog a governed engine if you put too much load on the rotor system because the governor will simply run out of throttle to give the engine. Having too much cyclic pitch can do this. You can also over speed if the governor reaches its bottom throttle point on an overly lean engine. They can also mask tuning problems so engines should be tuned correctly with the governor off.

>>If the engine is tuned to perfection then the only other things a pilot can change are the amount of throtle used and the blade pitch, A little less pitch combined with a little more throttle give a higher headspeed (which is how we all set up the speed we want), BUT this is then changing the basic setup which is the printed guide.
The same goes for a lower headspeed is created by lower throttle and greater pitch , again this is altering the basic setup instructions and guides printed. <<

From what I can read you are posting a rhetorical question here.

First of all the "basic setup" you referred to is ONLY a basic guide line for the "initial" setup for a model helicopter. It is in no way reflect the actual flight setup. Just like many glow fuel engine manufacturer recommend the user to open the high speed needle 2 turns before starting. It is by no means the final setting.

The main factor that will make the head speed so different for different user is the environmental condition. Some one flying at 8,000 feet above sea level will need to have a totally different head speed to keep the heli flying versus some one at sea level.

Head speed also is determined by the weight of your heli, gear ratio and what you intend to do with the heli once you get it out of ground effect.

So you are basically trying to simplify an observation a little too much.

However you are correct in your observation that the physical rotational speed of the rotor head is determined by collective, engine tuning, and throttlw setting. Then all that is due to size of engine, weight of heli, air density, humidity, air temperature, rotor blade efficiency, rotor disk loading...............