Re: 777 engine RPM

Date:         16 Sep 97 02:37:12 
From: (Alan Andersen)
Organization: CyberGate, Inc.
References:   1
Followups:    1
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On 11 Sep 97 03:35:28, (Steven Hargreaves) wrote:
>Anyone have knowledge of the approx rotational speed of 777 engines
>(inner core and fans) at take-off and cruise?  I'll split the beer I
>win if the fans do <30,000 rpm.

I do have the hard data.

Rotor speed at 100% for the PW4077/4084
N1	2,900 rpm
N2	10,800 rpm

At cruise speed, at altitude, these speeds are not much different
although the EPR is lower.  The higher the altitude, the faster the
speeds for the same EPR.  (less air density)

You win the beer!  It is MUCH less than 30,000 rpm.

Anything else you want to know about the 777?