View Full Version : Some engine questions
HEALY
12th Aug 2007, 07:55
Hi there
Trying to finalise my notes on a few things regarding Engines on CX acft
1) Do all 747-400 pax fleet have RB211-524H-T ( I saw mentioned of CFM -56???)
2) Are these engines flat rated to 58000lbs down to 524G type
3) Are the 747-400BCF keeping the same engines and thrust rating
4) TECH Q. Does the EPR reading given in the cockpit combine both core and bypass outlet pressure ie IEPR
Answers appreciated
Pogie
12th Aug 2007, 13:30
What I know (or don't know)...
1) Do all 747-400 pax fleet have RB211-524H-T ( I saw mentioned of CFM -56???)
I'm think that the Airbus uses the CFM56 engines, but the 400's definitely do not. The 400s either have PW4056 engines or the RB211's as you mentioned.
2) Are these engines flat rated to 58000lbs down to 524G type.
The RB211's have 58,000 lb. thrust. The PW's put out 56,750 lb.
3) Are the 747-400BCF keeping the same engines and thrust rating.
They have both engines, as mentioned above.
4) TECH Q. Does the EPR reading given in the cockpit combine both core and bypass outlet pressure ie IEPR.
Uh...I don't know. It just says EPR. There is no EPR gauge on the PW A/C.
Pogie
barit1
12th Aug 2007, 14:41
R-R has traditionally used IEPR (integrated fan duct & core duct data) - If the CX engines are different that would be a surprise!
But P&W's without EPR? can someone verify this???? :eek:
extreme P
12th Aug 2007, 15:35
4) TECH Q. Does the EPR reading given in the cockpit combine both core and bypass outlet pressure ie IEPR
Yes, intergrated EPR.
Its been a while since I flew one but IIRC the PW have EPR, but I suppose since the numbers are different (OMG not 1.18 on approach!) people tend not to look at them.
catpac
12th Aug 2007, 17:23
I thought the RB211-524HT was rated to 60,600lbs of thrust???
Macgyver
13th Aug 2007, 16:28
It's my understanding that the 524G's are rated to 58,00lbs, while the 524H are rated to 60,600lbs.
Dan Winterland
14th Aug 2007, 00:02
It's GEs which don't use EPR. RR and P&W do.
catpac
15th Aug 2007, 13:07
Thanks for clarification guys.