Fuel burn 737-200 vs 737-300

[aseanaero]

Whats the difference in fuel burn between the 737-200 and 737-300 over a 1,000nm trip ?

[enicalyth]

The 200 has a smaller wing and carries less payload but suppose take-off weight is 47 tonnes with 115 pax and it settles into long range cruise at M0.72 FL350 I'd expect it to burn off about 5700kg over a trip of 1000nm. The 300 has the larger wing, not as large as the NG and an appreciable fuselage stretch, hence the increased weight and payload. The take-off weight would be say six tonnes greater, i.e. about 53 tonnes with say 128 pax but the fuel burnoff would remain about the same thanks to more fuel efficient engines. Whereas the 200 would burn maybe 0.76 kg of fuel for each kg of thrust per hour the 300 would be more like 0.69kg/kg-hr. Flight time for both would be about two-and-a-half hours with the 200 just having the edge by a minute or so.

[OverRun]

enicalyth,

One of the pleasures of PPRUNE Tech Log is the acquisition of technical knowledge. You've now shown me the difference between the -200 and -300 in fundamental aeronautical engineering terms.

Thank you.

[aseanaero]

Thanks enicalyth ,

I second overun's post.

I was trying to figure out why operators with low utilisation like some cargo operators that could still legally fly the 732 would want to go to a 733 citing fuel efficiency as the reason if they are only flying 5 or 6 hours a day , huge difference in acquisition and parts prices , 732 parts are getting very cheap now as there's an oversupply compared to airframes still flying.

[c100driver]

Having flown both over the last 10 years the answer is:

MTOW of our B732 53070
MTOW of our B733 63276

On a one hour ten minute sector the B733 burn average about 3200 kgs and the B732 (Hush kit) averaged 4000 kgs and the B732 (non hush kit) averaged 3600 kgs.

The B732 crz at .72 and the B733 at .75 (CI 28)

Our B732 configuration 122 seats
our B733 configuration 147 seats