fbl

[satgod]

I was looking at the fbl systems on the market did alot of reading
I know alot of people really love the beastx but in my research I started to lean toward either the vbar or the skookum 720

I like the features and it seems to be a solid contentor

can anyone help me out with this

dont mind spending the money as long as I get something worth having

[desertstalker]

Originally Posted by satgod

I was looking at the fbl systems on the market did alot of reading
I know alot of people really love the beastx but in my research I started to lean toward either the vbar or the skookum 720

I like the features and it seems to be a solid contentor

can anyone help me out with this

dont mind spending the money as long as I get something worth having

If you want the Self levelling and governor, as well as all the logging then the SK is great. If you just want a simple, easy to setup FBL unit that cares not for vibrations (infact for the BeastX the harder mounts usually works better) then the BeastX is a great choice. The SK requires (if you want to use SL) more attention to detail regarding mounts and heli setup to reduce vibration, for most the MB you just tape on with 3M 4011 or 4010 and go for it.

IMO they fly much the same way, but I only fly sport so...

[CoolHandLuke]

i have a HC3-SX coming (it's my first fbl unit) it has self leveing to and i've been told that there not sensitive to vibration, i guess i'll see when it gets here.

[Luvmyhelis]

All true self stab units by nature have to be somewhat sensitive to vibrations or they will not self level accurately. The unit has to detect micro variations in axis changes and already be sending corrective measures to the cyclic servos well before any visible changes occur. That is, comparing vibe levels with non self leveling units.

Basically the Skookum forces you to set up your heli correctly and address cheesy parts or sloppy setup clearances that would be out of normal accepted factory specs. Unless of coarse the vibes that are considered normal by the manufacturer are actually vibrating the heli apart. In truth when the vibes get high enough to effect the self level feature they should actually be looked at as bad enough to cause concern. They fly perfectly with acceptable vibe levels, just knowing the vibes are there though drives guys nuts if they love the hobby. I have even flown one of my Trex's with horrendous vibes well over 20 and it flew as well as any fbl unit out there. It just wont self level until I get the vibes under control. And I have flown my other heli all fall with vibes of 5 to 6 coming out of the tail. The only permanent fix is to eliminate the entire nasty Align tail system, but the system I want is on backorder.

[desertstalker]

Originally Posted by Luvmyhelis

All true self stab units by nature have to be somewhat sensitive to vibrations or they will not self level accurately. The unit has to detect micro variations in axis changes and already be sending corrective measures to the cyclic servos well before any visible changes occur. That is, comparing vibe levels with non self leveling units.

Yep, no way around it, if you want SL you need lowish vibes. The accelerometers need a fairly low noise level (vibrations are acceleration as far as the sensor is concerned) to operate properly.

The Gyros in the SK are top notch, only thing better is the CGY750 by Futaba (that can pretty much be strapped to the side of your nitro cylinder and still work fine) and will continue to operate at vibration levels sufficient to make the skids/tail fin vibrate visibly. But if you want SL to work you need to keep things fairly well setup, or avoid Trex's, they seem to have a lot of vibe issues in the TT and tail.

[CoolHandLuke]

i was told that the HC3-SX has no accelerometers for vibrations to effect ?

[desertstalker]

Originally Posted by CoolHandLuke

i was told that the HC3-SX has no accelerometers for vibrations to effect ?

IR sensors, cameras, gps, compass? Needs a couple of those at least or levelling is going to be based on integration of gyro values and will drift over time.

[CoolHandLuke]

i do know that the HC3-SX has none of those so i wonder how it works so good ?

does anyone know more about how the HC3-SX works to self level without being sensitive to vibrations ?

[fusionsx00]

it does have a 3axis accelerometer

diffrent design, that's all.

more info in the flight stabiliaztion forum, here in helifreak

I think it has some sort of internal vibration reduction in side the case, and its a cnc case.

really they don't post much about the units workings,in there best intrest to keep this close to there chest.

[mkovalcson]

BTW GrandRC just sent an email out

SK-720 $339 until 12/8 If that makes things any easier.

[Luvmyhelis]

That is an excellent deal for a new one. The best consistent retail price for the pair, Sk + bus still is here http://www.rcgroups.com/forums/showthread.php?t=1265881

[CoolHandLuke]

you can find a 720 on ebay for around $350.00 most of the time, and there new in the box.

[jperkosk]

Originally Posted by Luvmyhelis

All true self stab units by nature have to be somewhat sensitive to vibrations or they will not self level accurately. The unit has to detect micro variations in axis changes and already be sending corrective measures to the cyclic servos well before any visible changes occur. That is, comparing vibe levels with non self leveling units.

Only if SL is based on 3 axis accelerometers. Basically excess vibrations can bottom out the accelerometer and the integral tracking of the horizontal plane goes down the drain. The vibration resistance will depend a lot on sensor construction, sensor mounting in the unit's case, and unit's mounting on the heli.

I have a Copilot II on 4 helis and it doesn't give rat's rear end about vibs, but of course it has other limitations.

[Warhorse]

I have the SK-720 on both my 450's and the ONLY time I ever had a problem with vibration shutting down the SL was when a tail blade grip bearing was going out. Frankly, I'm glad it did alert me somehow otherwise I probably might not have noticed until the tail blade went flying! It wasn't very obvious to look at it that there was a problem. Otherwise I haven't had any problems with vibration but then again, I'm super picky about getting the setup as close to perfect as I can when I build these things.

Yeah, I straighten pictures too. Totally OCD and proud of it!

[mkovalcson]

Multiple places are selling it for $339 right now.

HeliDirect
GrandRC

are two I know about.

I may order one for my upcoming TDR build.

[jperkosk]

Really? How come when I go to their sites I see $399?

[snowball75]

Put it into the shopping cart and then view the cart.

Sent from my Desire HD using Tapatalk

[mkovalcson]

HeliDirect specifically shows "MAP Price" next to the list price until you add it to the cart.

[CoolHandLuke]

yep shure enough, add it to the cart and "boom" $339.00, thats a great deal !

[bstanley72]

I wonder if this price drop is telegraphing something. Like a new unit or product? SK1440?