CP vs FP - Flying characteristics

[mstram]

My HBFP is airworthy again, using an Eflite 3-1 and a GWS Pico receiver.

I started some 'Radd Scooting' (http://www.dream-models.com/eco/flying-index.html) inside my condo, (though I AM using training gear).

I'm going very slowly, actually counting the clicks on the throttle :D

The heli gets "light on the skids" at about 9 clicks, and almost lifts off at 10. I'm now at 10-11 and it's
almost flying ! Woo hoo !

I think I'm finding one of the fundamental traits of FP helis, that being with the varying headspeed, the controls also vary quite a bit, much like a plane when it flies in "slow flight"

Not a huge suprise, as the different head speed helis in the sim react much the same way, though the FP heli isn't quite as accurate as the real thing in this low speed area.

Do the collective pitch helis have more consistent control input response?

I.e. from "light on the skids", to the hover, are the control inputs / reactions about the same?

I guess what I'm experiencing, is one reason some people recoomend "punching" it up a couple of feet off the ground. I may end up flying that way eventually, but I'd like to master the "gradual power increase / increasing control sensitivy", just for fun anyway, even it is more difficult.

Presumably I'm going to need to know those control response characteristics if I'm planning to land smothly, rather than just chopping the power :)

I think I'll be going outside tommorow for "click" 12+, as my ~9 square feet looks like it might not be quite enough at my current skill level :)

Mike

[tnarchitect]

I went from a HBFP to my current Trex 450 (i still fly the hbfp too) Here is what I found:

1) The control response does slow down as headspeed goes away. Go ahead and remove the flybar weights. With a CP heli, the headspeed is more or less constant and the controls are pretty solid, regardless of throttle position- given there is enought to get the heli flying.
2) You REALLY have to fly the tail. This is a good thing to learn.
3) Once you get to hovering, you will notice a definite lag in when you come off of the throttle, and getting back on the throttle in decents. You kind of have to anticipate when it will "bottom out" and give more throttle early to keep it from hitting the ground. With a CP heli, it pretty much is instantaneous. If it is set up right you can get it to stop on a dime vertically with just a twitch of the stick.

Other than those two things, the biggest difference is the crashability. The only time I broke anything on my FP other than landing gear, I packed it in from about 25 feet fast. Broke a 1.91 piece on the head. Get some SuperSkids. ALso, if you are going to keep flying it, I would replace the motor. Not necessarily a brushless, but a better motor w/ bearings. I did mine (can't remember what motor i think slowmax?). It makes a big difference- more head speed= more stability. Also break it in and it will last longer and be easier on batteries.

Hope this helps.

Brian

[anatoly]

I don't have an HBFP, but my friend let me fly his around a bit when we were diagnosing a vibration problem. I was't impressed with the stock radio. One thing you will find is that it's a lot easier to find the right hover throttle spot with a smooth throttle instead of the ratcheted throttle. The "clicks" just don't provide enough resolution. This also means that when you're going for a smooth landing, the right throttle position for a smooth descent may be somewhere between click 10 and 11. I actually think both my CP helis are easier to fly than the HBFP partly because I have finer control over the throttle using my DX7 than my friend's stock radio. Not that you can't learn with the stock radio, but it's one of the things to be aware of.

[patrick181]

My HBFP is airworthy again, using an Eflite 3-1 and a GWS Pico receiver.


I guess what I'm experiencing, is one reason some people recoomend "punching" it up a couple of feet off the ground. I may end up flying that way eventually, but I'd like to master the "gradual power increase / increasing control sensitivy", just for fun anyway, even it is more difficult.

Mike

Assuming you are a beginner, if not, I apoligize.

When you are comfortable with your directional control of the scooting, you should go ahead and "punch it up" persay about 3 feet to get out of ground effect quickly. You will find that the Heli is actually easier to keep in one position in the air than on the floor. There is not a difference in this effect between collective pitch and fixed, at least to me. Make sure to keep the tail towards you though. You should also loosen or remove the clicker, its just a small metal bar that rubs on a cam. They are very annoying for most heli pilots.

[mstram]

Assuming you are a beginner, if not, I apoligize.

When you are comfortable with your directional control of the scooting, you should go ahead and "punch it up" persay about 3 feet to get out of ground effect quickly. You will find that the Heli is actually easier to keep in one position in the air than on the floor. There is not a difference in this effect between collective pitch and fixed, at least to me. Make sure to keep the tail towards you though. You should also loosen or remove the clicker, its just a small metal bar that rubs on a cam. They are very annoying for most heli pilots.

When you punch it up, are you anticipating a left drift, and adding right cyclic?

If so, about how much stick?

On my slow / gradual power increase, I'm needing about 1/4 right cyclic, not sure if that's "normal" ?

Or does your HBFP pop straight up ?

The funny thing, is when I had the motor connections reversed (main motor on the tail connection on the 4-1), the heli DID pop straight up ... might have even been with full power I'm guessing. (I know that's not the correct way to setup the heli .. just an observation on what's it capable of under "abnormal" conditions

Mike

[mstram]

I was't impressed with the stock radio. One thing you will find is that it's a lot easier to find the right hover throttle spot with a smooth throttle instead of the ratcheted throttle. The "clicks" just don't provide enough resolution.

Well I'm not actually using the stock radio :)

Using my Futaba 6xas, but it still has the throttle clicks :D

The clicks are a minor concern right now, getting used to the cyclic inputs / throttle combinations will take some time before I'm probably close enough to a stable hover to worry about the fine tuning.

In the sim, I was compensating for the clicks by using the throttle trim. Might be a while before I can use that same technique on the real thing.

Mike

[mstram]

1) With a CP heli, the headspeed is more or less constant and the controls are pretty solid, regardless of throttle position- given there is enought to get the heli flying.


That's what I figured. Probably the reason why all?? full scale helis are CP


2) You REALLY have to fly the tail. This is a good thing to learn.


Assuming I want to stay tail-in for now, do you just mean that I have to actively maintin that tail position ... and not depend on the gyro ?


3) Once you get to hovering, you will notice a definite lag in when you come off of the throttle, and getting back on the throttle in decents.

You kind of have to anticipate when it will "bottom out" and give more throttle early to keep it from hitting the ground.


Ok thanks, when I get this #@^##$ tail motor mounted again, hopefully I can get to that point soon.


With a CP heli, it pretty much is instantaneous. If it is set up right you can get it to stop on a dime vertically with just a twitch of the stick.


Sure .. rub it in :D


Other than those two things, the biggest difference is the crashability.

The only time I broke anything on my FP other than landing gear, I packed it in from about 25 feet fast. Broke a 1.91 piece on the head. Get some SuperSkids.


Well I had a pretty "good" crash yesterday (flew into the side of my building) (http://www.crackroll.com/forums/showthread.php?t=782)


ALso, if you are going to keep flying it, I would replace the motor.


Bought it "used" (almost brand new really), with an Xtreme 380x / dd tail, super skids. I'm using training gear on it too

Mike

[CSpaced]

Well I'm not actually using the stock radio :)

Using my Futaba 6xas, but it still has the throttle clicks :D

The clicks are a minor concern right now, getting used to the cyclic inputs / throttle combinations will take some time before I'm probably close enough to a stable hover to worry about the fine tuning.



Its easy enough to remove the ratchet. Pop open the case on your tx, unscrew the spring on the ratchet and flip it around so the smooth side rides the ratchet. voilla :)

Don't forget about ground effect. When you are close to the ground your rotors will create lots of turbulent air which bounces right back up to your heli, tossing it about. Get a few feet up and it smooths out. You'll never have a heli that you can put into a hover and be able to let go of the sticks and it will just sit there. You are constantly correcting to keep it in one place, how much you have to correct it will depend on how well set up your heli is.

[dmulligan]

I recently moved from a HBFP to a HK450 (trex clone) and one difference I noted was that the 450, which is a much larger and heavier craft, has a much easier time flying within ground effect. With the HBFP I got used to popping up to at least a meter as it was much easier to control up there. When I was first spinning up my 450 I brought it up slowly, had it hovering a mere 20 or 30 centimeters off the ground. I noticed that it was MUCH more stable than the HBFP. Then I noticed that I was still in ground effect and I was comparing the stability of a HBFP out of ground effect to a 450 within ground effect. It is also amazing how much easier a 450 size bird handles some wind. The larger the heli the more wind it can handle.

I agree with a lot of what was said above. Yes the HBFP tail is harder to control. Yes the FP bottoms out a lot easier. Get rid of the flybar weights immediately, they make the FP hard to fly. Flybar weights are okay on a 450 but on the FP it is just too slow. The HBFP is harder to fly outdoors, and in fact it is just harder to fly. However the HBFP was a great trainer for moving up to a larger CP bird.

I would do the following (almost in order):
- Get a sim and practice
- Join a local indoor heli club that flies in a gym.
- Get rid of the flybar weights or at least move them in as far as possible.
- Get as much stick time on your FP as possible. Pop out of ground effect and first work on subtle movements of both sticks.
- Get rid of the training gear as quickly as possible as they will hindering your progress. Do this as soon as you can hover for more than a few seconds.
- Once you are able to hover the FP and are working on side in hovers get a cheap 450 clone and learn to build it while you continue to learn to fly the FP. I suggest the CopterX 450SA for $59 from ehirobo.com and check hk450.com for the parts list you will need from hobby city.