What did you do with your PRÔTOS today?

[aterren]

Originally Posted by deebee

Flew at 1600 rpm got a descent amount of lift, enough for slow vertical punchout.

<snip..> I think around 1900, 2100, and 2400 might be more what i am looking for ATM or 1800, 2200, 2400.
with needless details about things you guys already know

I have been running 1400, 2100 and 2400. This meets all of my needs and I only use 2400 for some tic-tocs and high speed low passes. I think I'll put another tooth or two on the pinion and have a bit of high(er) speed fun.

[deebee]

Originally Posted by aterren

I have been running 1400, 2100 and 2400. This meets all of my needs and I only use 2400 for some tic-tocs and high speed low passes. I think I'll put another tooth or two on the pinion and have a bit of high(er) speed fun.

What blades and pinion are you running?
13t seems to top out around 2400rpm for solid governor
15t seems to be around 2800 for the same.
the manual lists 100% throttle at 2550 for 13t, and 3000 for 15t.

Flew a couple packs, circuits, piro pogos, flips and rolls getting lower, started working on inverted hovering.
Had the radio strap post nut work it's way off, (post is pulled up out of detent turned 90° to work with balance arm) looks like post wasn't long enough to hit the nylon in the locknut. Brought her in quick for a mini Auto.
Thankfully I got the heli down and the radio off without any blue smoke from inside the radio. Back together with locktight.

[babyuh1]

When you are running a 3 cell does your ESC auto select or are you programming it for three cells?

[DoubleCH]

I set my YGE60 to auto detect lipo cell count so it detects 3S and 6S. Some suggest ESC may mis-count number of cells with 6S+ pack but I've never had such problem. If you run manual low start-power (e.g. 2%) 3S may not start. I run "auto" and it always starts.

[babyuh1]

Thanks, I have a YEP to install in mine but I'm running a Hobby King heli ESC now and I just lied to it and set it to three cells. I always time my flights so I won't have an issue on six.
I flew it with a 2650 MAH three cell and it was a blast! Nice, quiet and slow!
Flew it for over seven minutes and used around half of a battery!

Going to hook up the Robird to the laptop and see what the head speeds were.

[kingmeow]

With 3S, do you have to add weight up front to balance the CG or the FBL will compensate?

[deebee]

The flybarless will compensate , but you are introducing an error of sorts so there may be some noticeable quirks, pitching up, might cause flip rates to be uneven etc.
From my experience, you probably won't notice too much of a difference sport flying.

Been getting a lot of attention here and there with fff , flips, rolls and
crappy looking loops.
Had a guy with new interest, ready to graduate from mallcopter, stop and ask for advice, all the while telling me I was the greatest pilot that ever lived.
I tried to keep a straight face and thank him. Rather I laughed my head off and told him the truth that really I can barely fly

[babyuh1]

I had to mount the battery as far forward as possible and then I still had to give it two clicks of down elevator to get it to hover correctly. Didn't notice any problems in flight.

[DoubleCH]

Only flybar setup will need "a few clicks" with the elevator. FBL compensates for CG imbalance and will not need (or cannot use) subtrim.

I didn't even bother flips and rolls with 3S so CG didn't matter. If it did I could've run 2 3S 2200 in parallel. My friend flew a 3S 5000 which made perfect CG.

[babyuh1]

"Only flybar setup will need "a few clicks" with the elevator. FBL compensates for CG imbalance and will not need (or cannot use) subtrim."

This is incorrect! And I used trim not subtrim. My heli wanted to fly backwards until I trimmed it out. If you have self level you might not need to but with a normal FBL you may.

[DoubleCH]

Originally Posted by babyuh1

This is incorrect! And I used trim not subtrim. My heli wanted to fly backwards until I trimmed it out. If you have self level you might not need to but with a normal FBL you may.

No, that's incorrect. If you need to use trim or subtrim for FBL to prevent drift you have a badly calibrated TX, a bad FBL, or you have a bad FBL/mechanical setup. You should never trim or subtrim an FBL, period.

[deebee]

Originally Posted by babyuh1

"Only flybar setup will need "a few clicks" with the elevator. FBL compensates for CG imbalance and will not need (or cannot use) subtrim."

This is incorrect! And I used trim not subtrim. My heli wanted to fly backwards until I trimmed it out. If you have self level you might not need to but with a normal FBL you may.

What FBL are you running?

[babyuh1]

Originally Posted by deebee

What FBL are you running?

Robird G31. I see the same thing with my MCPX if I use a large battery or if I have the battery in a different place than normal.

Normal FBLs don't correct for poor mechanical setup. You should never rely on your FBL to balance your heli even if it has self level capabilities!

[jmtyndall]

The mcpx isn't a normal fbl. It's a half-azz one at best. Vbar and Brain will absolutely compensate. Also, adding trim is no better of a method of setting cg than "just letting the fbl compensate"

[babyuh1]

Originally Posted by jmtyndall

The mcpx isn't a normal fbl. It's a half-azz one at best. Vbar and Brain will absolutely compensate. Also, adding trim is no better of a method of setting cg than "just letting the fbl compensate"

First, using trim while flying is no different than you moving the sticks, and Second, I didn't know that Vbar and Brain automatically self leveled!

I have an IKON unit for my next build ( a carbon stretch P 500) but haven't installed it yet. It has self level but you have to set it up and hit a button to engage it.

Do you have to do any setup to get Vbar and Brain to fly right or do they just automatically compensate for off balance and other setup issues?

[DoubleCH]

Originally Posted by babyuh1

First, using trim while flying is no different than you moving the sticks, and Second, I didn't know that Vbar and Brain automatically self leveled!

You misunderstand the basics.

First, in flybar setup your cyclic input controls the amount of force to pitch/roll the heli. In flybarless setup your cyclic input controls the pitch/roll rate. This is why people recommend pop the FBL heli up in the air don't do slow take-off. When you give cyclic input with the heli on the ground, a flybar heli will try to pitch/roll with the requested force. The more cyclic you add the more force is applied until a lot of cyclic input is needed to tip over the heli. When you do the same with a flybarless heli, your cyclic input is telling the FBL to pitch/roll the heli at a requested pitch/roll rate (like how many degrees per second). When there's resistance because of the ground the FBL will til the swash more until it achieves the requested pitch/roll rate making it take so much less cyclic input to tip over an FBL heli on the ground. This is also exactly the reason why FBL heli is less susceptible to wind than flybar... because FBL compensates for pitch/roll rate induced by the wind. By trimming cyclic with an FBL setup, you're telling the FBL unit to have a constant pitch/roll rate with center cyclic stick. This will affect every algorithm like piro-compensation, direct-cyclic-feed-forward (BeastX's term to add direct swash movement in respond to cyclic input on top of controlling pitch/roll rate), flight style, agility, etc. that needs center cyclic stick position as reference point.

Second, vbar doesn't self-level. To do FBL gyro needs accelerometers to detect pitch/roll angles. Vbar, Robird, and most FBL gyros don't have accelerometers. They have gyros which detect pitch/roll rates. The reason why FBL gyro will keep heli with bad CG level no drift even without accelerometers is that the FBL gyro monitors pitch/roll rate. With center cyclic stick, FBL will make sure there's zero pitch/roll rate, even if it means the FBL needs to tilt swash to compensate for the off-CG.

You have to note the difference between how FBL gyro with and without accelerometers to maintain no drift. Without accelerometers, you'll need to move cyclic until heli doesn't drift AND THEN release cyclic to center. With zero pitch/roll rate maintained, the FBL gyro will hold the heli at that attitude thus preventing drift. With accelerometers, you do NOT need to move cyclic until heli doesn't drift before you release cyclic to center. You can release cyclic to center any time with heli in any attitude and the accelerometers will tell the FBL gyro to change back to the level attitude.

Do you have to do any setup to get Vbar and Brain to fly right or do they just automatically compensate for off balance and other setup issues?

Speaking of vbar, Robird, or any other FBL gyro, you need to set it up to NOT use any trim.

[babyuh1]

Thanks! Nice explanation!
Too bad it doesn't fit with the reality of my heli. Of course what you are explaining is why you don't use sub trim on a FBL heli. Or at least one of the reasons for not using it.
It will be interesting to see how the Ikon works on my P 500 stretch because the Robird works perfectly with three clicks of trim to offset the balance problem from the light battery as it would continuously drift backwards without it no matter how many times you brought it level first!
I'm converting my 50 nitro to FBL with a Robird now, so I'll let everyone know if I ever get the P500 stretch finished!

[jmtyndall]

Ummmm no. You absolutely do use subtrim to get the channels zero is setup. You absolutely don't use trim, because as mentioned before, with a fbl heli your controls have no effect on the servos on the heli. By adding trim it's just like pushing the sticks

The only time you should notice cg issues on a fbl heli is in a full out piro. Piro comp is pretty good at adjusting for it, but you will tend to see a wobble in the disk. It just should not drift

My Mini Protos is tail heavy. It doesn't drift. It doesn't need trim.

[babyuh1]

"My Mini Protos is tail heavy. It doesn't drift. It doesn't need trim."

That's nice for you but it doesn't help my heli stay in one place.
Using trim on your heli is the same as if you are holding a small amount of control. The controller doesn't know if it's you holding it or your transmitter.
Sub trim is bad as it makes the center of the servo throw off position. I've always read that you should never use sub trim to correct your mechanical setup if you can help it!

[DoubleCH]

I don't know what you get your info but it's all reversed. The only reason subtrim can be used in FBL is if the FBL is primitive like the 3GX which stimulates flybar setup except 3GX intercepts servo signals for stabilization. In that case subtrim (for individual servo) is the only way to set up 3GX. But still, you should NOT use flight trim which tells 3GX you want a constant pitch/roll rate at center stick. If Robird is something like 3GX I would run not walk away from it like I do my 3GX. Modern FBL is so good there's no need for (or I should say you cannot use) flight trim to adversely affect FBL operation.

In short you should NEVER use flight trim to adversely affect FBL operation. Subtrim OTOH is only needed on primitive FBL like the 3GX.