Heli Backflips-while-spoolingup feature.

[ignaceous]

I just became aware that a great number of 450X where shipped with the backflip feature set to "ON". Anyone know how to turn this thing off? I have no use for it.

Thanks in advance.

Here's some footage
https://onedrive.live.com/redir?resi...nt=video%2cmp4

[HEXAHYDRATE]

Um. ...

[ArchmageAU]

Originally Posted by ignaceous

I just became aware that a great number of 450X where shipped with the backflip feature set to "ON". Anyone know how to turn this thing off? I have no use for it.

Thanks in advance.

Here's some footage
https://onedrive.live.com/redir?resi...nt=video%2cmp4

Never seen that feature before.

1) Probably best not to spool up inside (especially to flying speed which is where the blades exert enough push on the air to move the model's CoG).
2) Ensure there is no vertical play in the main shaft (up/down)
3) Is this a GPS rigged 450X? As a usually there is no umbrella RX/antenna off the boom on a stock 450X
4) Does the swash plate move if spooling without blades (mains and tail)?
5) Should be smooth through the entire spool up. Try a normal mode spool up VERY slow and stop or TH if it starts to get shaky.
6) Is their excessive vibration when spooling without blades (bent shaft(s), bad bearing(s), etc..)?
7) Have you checked the AR7200BX setup? Do all the servos work in the correct direction when you tilt/rotate the model?

Interesting to find the result.

Flip/spooling is not a feature I am familiar with.

[ignaceous]

Originally Posted by ignaceous

I just became aware that a great number of 450X where shipped with the backflip feature set to "ON". Anyone know how to turn this thing off? I have no use for it.

Thanks in advance.

Here's some footage
https://onedrive.live.com/redir?resi...nt=video%2cmp4

Update link: https://1drv.ms/v/s!AnoQHOB8F6tLgswAgj9C4ATJ_V1tSg

[ignaceous]

Originally Posted by ArchmageAU

Never seen that feature before.

1) Probably best not to spool up inside (especially to flying speed which is where the blades exert enough push on the air to move the model's CoG).
2) Ensure there is no vertical play in the main shaft (up/down)
3) Is this a GPS rigged 450X? As a usually there is no umbrella RX/antenna off the boom on a stock 450X
4) Does the swash plate move if spooling without blades (mains and tail)?
5) Should be smooth through the entire spool up. Try a normal mode spool up VERY slow and stop or TH if it starts to get shaky.
6) Is their excessive vibration when spooling without blades (bent shaft(s), bad bearing(s), etc..)?
7) Have you checked the AR7200BX setup? Do all the servos work in the correct direction when you tilt/rotate the model?

Interesting to find the result.

Flip/spooling is not a feature I am familiar with.

1: Happens outdoors too.
2: No play.
3: VTX ant. Will check for vibes ty.
4: Doesn't.
Going to test #4
5: vibration begins before lift. During lift entire bird solid as a rock. Don't see how TH would help here though.
6: Will check.
7: Yes. Bird is airworthy. Just mentally challenged (can I still say that?) spool up.

Thanks for the advice!

[ArchmageAU]

Originally Posted by ignaceous

1: Happens outdoors too.
2: No play.
3: VTX ant. Will check for vibes ty.
4: Doesn't.
Going to test #4
5: vibration begins before lift. During lift entire bird solid as a rock. Don't see how TH would help here though.
6: Will check.
7: Yes. Bird is airworthy. Just mentally challenged (can I still say that?) spool up.

Thanks for the advice!

1. General observation - NEVER spool a 450 to flying speed in an enclosed space - could ruin your entire day / week / month considering blade tip speeds required for flying.
2. Good to know - eliminates one cause. I had this on my X5 after one repair. Was fine till light on the skids, fortunately could set it down with no damage and diagnose and fix problem.
3. FPV or video link - should be fun once flipover problem resolved. Chase vibes first with blades off. Vibes will make bad video signal too (really have to damp camera mount)
4. Good. Twitchy or locking servos can cause this issue too.
5. Could this be ground resonance? (This is where vibrational feedback wants to shake the heli apart. Takeoff or shutdown are the only options) Rare for an RC Heli, but not unheard of.
6. Awaiting your investigation. All rotational system vibrate. It takes expert balancing to remove ALL vibration (see gas centrifuge if you want the most extreme example - these are large and spin so fast that any imbalance will destroy them almost instantly - They are used for nuclear enrichment, so the build process is often shrouded in secrecy - also requires Maranging steel to cope with the forces involved).
7. Also look into FBL feedback. If the angle the FBL is commanding the heli to attain does not match the ground angle (and you are too slow to take off), it can tip over as the FBL unit tries to get more insistent on attaining the commanded attitude. Quite a few recommend do not touch the cyclic during spool up and takeoff quickly. I usually go for ensure you are flying the heli even before the blades are at full speed (watch the rotor disc carefully once the blades at full extension and ensure they remain flat).

Best of luck.