FBL Gyro Vbar Neo And Mini Basic Setup And Tune

[murankar]

I pulled this tuning procedure from General Tweaking Order | VStabi. This is what Mikado recommends for the initial tuning of a Vbar or Neo.

Some basic infos how tweak main rotor and tail rotor can also be used in the links.

Best preconditions are:

• blades (fold method) are at 0deg in setup (locked) position
• Cyclic Ring set up as best in hover collective point
• Tail throws set in useful ranges
• paddle sim and pitch pump are zeroed
• style is at 70...100
• useful gear/kv/cell count setup for the target RPM

Step 1 - Basic Gov settings:

• Gov Gain to 0
• Gov I to 0
• Spoolup at zero collective
• dial in basic throttle unless HS matches
• go to a hover, dial in collective add unless HS will be kept under hover too
• do a medium climb, check hs, possibly add some collective add again
• set cyclic add to 1/3 of collective add
• turn back gov gain and Integral

Step 2 - Basic Tail together with Gov:

• lower tail gain (e.g. to 40)
• hover and do medium climbs
• on a CW heli - if nose turns to left in the climbs - increase collective torque precomp in tail
• if it stays approx. - the optimum has been found.
• if it still turns although the precomp is e.g. at 60 - decrease (!) the collective add of the governor (tail is overloaded by too hard gov'ing)
• set cyclic precomp to 1/3 of collective precomp

Step 3 - Tail gain:

• just increase ad needed to hold the tail. The VBars have a internal gain calculation depending on the flight situation to avoid oscillations - e.g. in fast flight.
• If the tail holds well - not more gain needed

Step 4 - Elevator Precomp:

• lower main rotor gain to 30-40 (approx 1/2 of the usual recommended gain)
• from a hover - start a climbout
• watch the tail boom. If it hangs down first - increase the precomp

All steps below can be done in different order:

Step 5a - Trim flight

• as the tail torque precomp changes the tail "center" - the TF will be done after the steps above to be perfect
• perform the trim flight on a calm day
• lift off, hover hands off for some seconds, repeat a few times
• if a hands off pirouette stays in place - end trim flight

Step 5b - Swash Optimizer:

• dial in the target agility, this resets the cyclic optimizers!
• do some constant rolls and flips in all 4 directions with approx. 50-70% of the stick throw.
• lets say 5-10 each direction will be ok, turn the optimizer off

Step 5c - Tail Optimizers:

• do some pirouettes in each direction
• also some stops (5 each side will be ok)
• turn the optimizer off
• if the stop is a bit softer on one side (due some physics) - increase the stop gain, see if it helps
• if it won't help - lower the tail acceleration which gives a bit softer response but more equal behaviour (optional, lower down to 45 ans less, often used on weak scale tails with 30)

Step 5d - Main Gain:

• increase unless you won't notice changes anymore.
• not critical - so it is possible to keep it at 80 on a usual helicopter

Step 5e - the rest:

• dial in Style as preferred (low = more smack, high = more precise)
• same with paddle sim
• and pitch pump (but - if using this - the tail will show up the limit again ...)

And of course - to be perfect - most of this can be done for each bank.