Hawk Pro Max Pitch?

[907Heli]

I've managed to fly my Hawk Pro successfully but it always seems lacking in collective control. So, I set up the blades with everything at zero pitch with sticks and servos centered, and it won't even lift off the ground. I lengthened the rod to give it more positive collective and I was able to fly it around but it felt heavy. I want to do some mild 3D and I'm concerned that I don't have enough pitch control so I added a longer servo arm to get more throw out of the collective and now the collective arm is maxed out against the frame. I haven't tried it yet but I was wondering what the max values might be or if anyone had some advice.

I'm also thinking my head speed might just be too low. This is my first nitro heli and it's quite a bit different than my planes. I don't have a tach so I don't know where it's set. When coming out of fast forward flight and descending for a landing it revs up really high and sounds like it's going to blow up but after reading posts about how horrible the stock black pipe sounds I'm wondering if I'm just not used to it and running my head speed too low.

I downloaded one of those head speed apps that works off the sound to try out. Anyone used those before?

Also, what head speed is appropriate for this heli? I have the stock plastic head (which I heard can't handle very high speeds) with stock wood blades, but I just got a set of FRP blades in that I'm going to run from now on.

I appreciate your help. It's snowing again so it will be a while before I get to take it out again.

[Lieutenant Dan]

Alaska !!!! oh man berrrrr

your cyclic, the first thing you do is remove those flybar heights, that will help a good amount, then get back to us on that
next, if you want even more, look at the top plate on the swash, if it has different length balls you can replace the short balls with longer ones,
plus there are longer balls for the seesaw, these are special balls that have longer threads for that seesaw

as for the head speed, if there is know one around that knows more about helis maybe you should get a governor, there are optical tachs, but they cost as much as a good governor, I recommend the multigov

just know, (for safety) not to twist wood blades over 1800, that a must know

edite> you can run the stock head up to 1800/1850, I know some people have run it higher, but I can't say what is safe, you just never know, you know. I do know if you had the 6mm spindle and thrust bearings you could turn up to 2000 cause I have been there

let us know how it flies after you remove those bar weights

[Dennis P]

For collective you will want about 10 deg of pitch to start and see how it pulls that once everything is tuned.What do you have for pitch presently? Is the headspeed coming up when you are trying to lift off or is it smoking allot and sounding like it is missing? A tach is a great tool will setting up glow helis.If you have people around that have tuned them for years it is different but when you are not sure what 1700 or 1800 sounds like they are worth there weight in gold

[907Heli]

I'll have to recheck my pitch. The engine sounds great. It doesn't smoke excessively or pop or anything, I just downloaded a sound powered headspeed app to try out and maybe it will help.

When I'm checking that 10 degrees, that's just collective pitch right? What is the max combined collective/cyclic pitch I can use? When manufacturers say +- 14 pitch range, are they talking about collective only? Seems like you should be able to have that 10 or 12 degrees of collective, and still have room to put in more for cyclic without binding the swash. Am I thinking about this correctly?

[Dennis P]

Yes the 10 deg will just be collective and the cyclic will be added to it.Put the pitch at zero and the blades inline with the tailboom and check you cyclic throw .You must be at zero then pull the cyclic to the side and check you pitch.After go full collective and cyclic in all corners to check for possible binding.

[MotorRotor]

I would suggest that you check the two washer/spacers that fit between the outer bearing in each blade grip, and the retaining lock nut on the spindle. The smaller one goes on the inside against the bearing and the larger one goes on the outside against the nut.

If either are reversed on one or both grips, once the rotor spools up the resultant binding between the large washer and the bearing will limit your pitch (you will not be able to get the same pitch you do on then bench) and you will not be able to get the climb rate that is normal.

Check out the photo diagrams on the top of page 12 of your Hawk Pro instruction manual.

[907Heli]

Motorotor, I finally had good enough weather to bring out the hawk. For some reason the tail went nuts on me and I took it up a bit to keep it from hitting a couple cars and then the motor quit on me and I got to try my first autorotation. Well, I failed my test and plopped it on the ground from about 15 feet up. Bent up the lower frames in front of the engine and some other stuff. Bent the main and feathering shafts.

Long story short, when I was replacing the feathering shaft I found one of the pairs of washers reversed with the large washer against the bearing.just like you said it might be. I'm excited to get it back in the air and see if that was the problem all along. Now I'm wishing I had just taken the time to check when you told me about it. Thanks for your help man. I'll let you guys know how it goes.

[MotorRotor]

Originally Posted by Aksport

............Long story short, when I was replacing the feathering shaft I found one of the pairs of washers reversed with the large washer against the bearing.just like you said it might be. I'm excited to get it back in the air and see if that was the problem all along. Now I'm wishing I had just taken the time to check when you told me about it. Thanks for your help man. I'll let you guys know how it goes.

Sorry to hear of your mishap.

Almost every time I have come across people with the symptoms you described, at various events over the years, I found it to be caused by the reversing of these two washers on either one or sometimes both of the blade grips.

The sequence for their installation is clearly shown in the manual, but I think that in our haste, we sometimes do not look it over properly when assembling the head initially or after a repair. I must admit that many years ago it even happened to me!

Happy flying.