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Jetcat P120 thrust level help needed

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Jetcat P120 thrust level help needed

Old 02-02-2017, 02:49 PM
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ajp
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Default Jetcat P120 thrust level help needed

I am getting a older model ready to fly again. It has a 14 year old Jetcat P120 in it. I have the rpm set to 115000, and cannot find the graph that compares thrust levels to rpm. Does anybody know what thrust level I am getting at 115000?

Thanks
Paul Appelbaum
Old 02-02-2017, 03:08 PM
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Vincent
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Here is what I found on an old rcu thread.
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Old 02-02-2017, 03:32 PM
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rhklenke
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Originally Posted by Vincent View Post
Here is what I found on an old rcu thread.
Good find! I always thought it was interesting how the majority of the thrust is at the top-end. A 6.5% reduction in RPM reduces thrust by over 20%...

Bob
Old 02-02-2017, 03:51 PM
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ajp
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Thanks, that is exactly what I was looking for

Paul
Old 02-02-2017, 03:52 PM
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Vincent
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Originally Posted by rhklenke View Post
Good find! I always thought it was interesting how the majority of the thrust is at the top-end. A 6.5% reduction in RPM reduces thrust by over 20%...

Bob
After taking a quick glance at it I was surprised too.
Vin...
Old 02-02-2017, 04:30 PM
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Zeeb
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Typical of turbine engines. They say with full scale that 50% of the thrust is created in the last 10% of RPM. I don't imagine their tiny counterparts would be much different.
Old 02-03-2017, 10:44 AM
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John Redman
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Paul,

The thrust figures listed by Vinny are for the latest versions of the P120's, mainly the SX version. If your engine is indeed 14 years old and has a serial number of under 1400 I would guess it will push around 24 - 25 pounds at full tilt unless it has been fully upgraded with the new style compressor, EGV, Diffuser, Chamber. The P120's from the serial number I listed above and older were around 24 - 25 pounds of blow. At 115,000 I would guess it is pushing closer to 16 pounds.

Just what I recall from running thousands of these engines over the years on test stands, etc.
Old 02-03-2017, 03:16 PM
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[QUOTE=John Redman;12302529]Paul,

>>>

Hi John...are you sure about that the thread I got that info from is from 2006 and the P120sx had a max rpm of 125k and 30-31lbs thrust??
Vin...

Last edited by Vincent; 02-03-2017 at 03:19 PM.
Old 02-07-2017, 01:20 PM
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John Redman
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Yes Vin, at 125K the P120-SX would hit 30 - 31 pounds. I am sorry, I was thinking the traditional 123K.
Old 07-14-2018, 06:28 PM
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I have a P120sx, serial no. 3476. I noticed that the ecu is set
at 123K max rpm. Can this turbine be run safely at 125K, and if so
can that be programed through the GSU?
Old 07-15-2018, 03:50 AM
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ledd4u
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Originally Posted by John Redman View Post
Paul,

The thrust figures listed by Vinny are for the latest versions of the P120's, mainly the SX version. If your engine is indeed 14 years old and has a serial number of under 1400 I would guess it will push around 24 - 25 pounds at full tilt unless it has been fully upgraded with the new style compressor, EGV, Diffuser, Chamber. The P120's from the serial number I listed above and older were around 24 - 25 pounds of blow. At 115,000 I would guess it is pushing closer to 16 pounds.

Just what I recall from running thousands of these engines over the years on test stands, etc.
Your statement is neutral in context. Before 1400 24-25lbs. Above 1400 25-25lbs. Sounds like tax brakes. Just a little confused about the statement. I own a serial number 2455 and its definitely more than 25lbs. Non SX, those are simply a POS from what I read.

Last edited by ledd4u; 07-15-2018 at 04:00 AM.

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