[SOLVED] did rescue system kill my tail boom ?

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scvflyer
Posts: 98
Joined: Wed 22. Jul 2015 16:02:51

Hi serviceteam and every interest,
I have a align trex 600 and configured rescue system to upward main rotor upwards every time. Flying upside down I used rescue system - that ends in a crash because main rotor blades hits into the tail boom. I used rescue system once before without any problem - but flying upside. Servos seems to be ok. I use spirit standard system with SW version 2.1.0 and 80% at rescue system.
Therefore what has been going wrong?
thanks in advance and br
siggi
ZeXx86
Site Admin
Posts: 12836
Joined: Mon 29. Apr 2013 16:06:44
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Hi,

that is very sad. As described in the manual and the software there is unfortunately possibility for boom strike, when configured angles are too high and/or head speed is relatively low.

Please see this page:
http://manual.spirit-system.com/index.p ... e_(Normal)

If there is a track of the blade in your tail boom, then this probably happened. To prevent this, you have to set recommended angles by the manufacturer, so they are in a safe range.

In any case I hope that you will fix the helicopter soon and it will be flying again with no issue.
Spirit System developer
scvflyer
Posts: 98
Joined: Wed 22. Jul 2015 16:02:51

Hi serviceteam,
heli's angel has been configured like manufacterer adviced. RPM has been round about 1850. Is that okay or an explanation causing into crash ?
thanks in advance and br Siggi
Adrian
Posts: 204
Joined: Thu 08. Oct 2015 14:43:12
Location: Switzerland

Hi Siggi

I had to lower my cyclic ring a lot to whats mechanical possible with my SOXOS as this is one factor on how aggressive rescue works.
With cyclic ring you tell FBL whats possible and in case of rescue, FBL does what's possible. I reduced it to around 9-11°.
With 1800rpm on 600er you are at lower end of rpm to go for 3D, which rescue is kind of if your upside down, I would go for aggressive rescue only above 2000rpm.

My best practice, I do only use arco rescue to avoid any intense cyclic action doing rescue, as this adds load to main, reducing head rpm and rising risk of Boom Strike. For me, rescue only got one goal, to get Heli away from ground, upside down, I don't care. - And there is on third factor, the Rudder Gain with Heading Hold, while flying with 45% to get solid Tail, on Rescue I only use -35%. Tail uses lot's of energy from main rotor to hold during aggressive cyclic inputs like rescue, I don't care if Tails Holds like a rock during rescue all I wanna, use the energy to get away from ground.

regards, Adrian
Oxy4max SpiritPro + HW // SOXOS 550, SpiritPro, HW120A V4, 920KV // SOXOS 600, SpiritPro, HW160A, Pyro650 // SOXOS Strike7, SpiritPro, HW160A, Pyro750 // Skywing Spirit Aero // FrSky Horus X10S + Taranis X7 /
scvflyer
Posts: 98
Joined: Wed 22. Jul 2015 16:02:51

Hi Adrian,
okay - now something becomes clear. Thanks for detailed explanation. ( :D :D :D :D ) I will follow your advices - at the end you are right "secure heli for jumping grounds is needed - not more " ;-)

good flights all the time and
br Siggi
jgiannakas
Posts: 183
Joined: Sat 02. Jan 2016 12:17:50

at rescue your heli is using the max cyclic pitch and whatever collective you've set it to use at rescue.

On all my models (450L, goblin 500, goblin BT) I have rescue collective set at 70% which gives 9.5 degrees collective. Cyclic is at 10 degrees. So overall my heli will not see more than 20 degrees of cyclic. The goblin states 12.5 on collective max and 10 on cyclic so there is a bit of margin.

I would strongly advise not to go over those figures when setting up rescue. For example any value over 70% on collective with more than 10 degrees cyclic is pushing it :) especially if you are running over 12 degrees max collective pitch.
scvflyer
Posts: 98
Joined: Wed 22. Jul 2015 16:02:51

Hi jgiannakas,
thanks for sharing your experience with me and us.
br Siggi
scrambled
Posts: 85
Joined: Sat 11. Apr 2015 18:07:33

Adrian wrote:...
For me, rescue only got one goal, to get Heli away from ground, upside down, I don't care. - And there is on third factor, the Rudder Gain with Heading Hold, while flying with 45% to get solid Tail, on Rescue I only use -35%. Tail uses lot's of energy from main rotor to hold during aggressive cyclic inputs like rescue, I don't care if Tails Holds like a rock during rescue all I wanna, use the energy to get away from ground.

regards, Adrian
Thank you!
Very useful info.

I lowered Rescue tail gyro gain a bit.
Most important is to get away from gound! :mrgreen:
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