Hi,

I am a little new to vibration analysis with Spirit and got two readings from mainrotor with Y-Axis but only one on Z-Axis. As the readings are without blades I like to investigate the reason but I am not sure at which rpm the are running as only frequency is shown. So perhaps anybody has an idea with multi gera soxos what could cause this (it is a new model) or how I can calculate the specific rpm.

In my oppinion hat could be caused by the multiple gear?

Regards,
Nils

Hello,

the upper plot has vibration spike caused very likely by Main rotor. And this could be really just gear that is not perfectly balanced.
Without a load this is often normal. Sometimes a lubrication of the gears can help a lot.

The vibrations are quite good. But with a tail blades it could be significantly different.

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Spirit System developer

Hi,

I unmounted the head and the right spike stays in place, so should be the gear. Can I calculate safely the rpm of the vibrationsource?
I tried this https://www.convertunits.com/from/hertz/to/RPM but got for 60hz 3600rpm. Is that correct calculation?

Is 25% interessting with gear only? I read that higher than 50% should be investigated but I am not sure if this is the critical line only or everything below is really fine. So you write that the spectrum shown is quite good I think it is the second?

Cheers,
Nils

This vibration level is OK, so no need to investigate.

You can try our Spirit Settings software which will tell you source of the vibration and RPM as well.

To get RPM of any frequency simply multiply Hz * 60.

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Spirit System developer

Hi,

I mostly worked with the Wifi-Interface because I cannot install software easily on my work laptop.
Tried it (looks very cool) and got strange behavior without tailboom and head mounted (see video - main rotor vibrations are going down and up; at 30s there are extreme vibrations along the whole spectrum). Any ideas about it with your experiance?

https://readycloud.netgear.com/client/d ... -55-17.avi

To describe the past...I had two issues during flight...very high tail vibrations and also reaching 2000rpm there is a critical wooble on the head.

Cheers,
Nils