Re: PW JT-8D Cruise Parameters for MD88 and B-727

From:         vwfixer@goodnet.com (Shane Dean)
Organization: GoodNet
Date:         09 Nov 95 02:19:08 
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Followups:    1 2
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In article <airliners.1995.1708@ohare.Chicago.COM>, tristar500@aol.com
says...
>
>Lot's of people ask for this kind of information so here's a list of
>engine parameters for a B727 and an MD88 at cruise.
>
>>>727-200 with JT8D-15A engines
>Gross Wt - 147,000
>IAS - 300
>Altitude - 33,000
>Mach - .84
>Ram Air Temp - minus 14
>Static Air Temp - minus 17
>Stab Units - plus 10
>
>EPR - 1990/2000/1990
>N1 - 88.8/87.5/87.0
>EGT - 480/480/470
>Fuel Flow - 3500/3300/3300
>N2 - 87.8/87.6/88.8
>Oil Temp - 86/92/95
>Oil Press - 47/48/45
>
>>>MD88 with JT8D-219 engines
>Gross Wt - 110,000
>IAS - 309
>Altitude - 28,000
>Mach - .782
>Ram Air Temp - minus 05
>Static Air Temp - minus 32
>Stab Units - plus 03
>
>EPR - 1669/1670
>N1 - 80.8/81.3
>EGT - 410/417
>Fuel Flow - 3550/3600
>N2 - 88.0/88.7
>Oil Temp - 86/86
>Oil Press - 48/48
>
First of all, my question is... what are these numbers?!? E.P.R. is usually
around 1.00 or so. 1990-2000?  JT8D engines (at least the ones I work on),
don't burn this much fuel, even at T/O. Possibly, I don't understand these
numbers because there is no ref point, ie. idle/Take-off (cruise would be
signifigantly less than T/O I would assume). Well, those are my questions,
because I have an enquiring mind and I'd like to know. ;-}