737-700 vs -800

[topend3]

hey what is the actual difference in performance between 737-700 and the -800, are they the same powerplant. anyone with any figures, i know the weights obviously differ, anyone with cruise speed comparisons and fuel burns???

[OzFlight.net]

Topend3

According to our Aircraft Type Search (http://www.ozflight.com.au/rego/types-res-type.php?make=BOEING) here is a brief extract regarding the -700's and -800's here in Australia.

Qantas 737-800's all use CFM-56-7B24 engines and have a MTOW of 78390kg

Virgin's 737-800's also use the CFM-56-7B24 but have a MTOW of 79180kg

Virgin's 737-700's have an MTOW of 69000kg. The register shows different powerplants of the same model tho. CFM-56-7B (20/22/24).

According to CASA's figures I'd say that the 700's cruise performance would be crap as all the 737-700's in Australia have fixed landing gear !!!! :D

[shakespeare]

Ozflight. Not too sure what you mean by "fixed landing gear". The last one I flew the gear came up just fine.

At 41,000 feet, approx 55 tons at M.78 the 700 burns around 1900 kg/hr, give or take a couple.
At 41,000 feet, approx 60 tons at M.78 the 800 burns around 2200 kg/hr, ditto.

Some of the Virgin 800's have 26K engines and some of the 700's have 22K engines. The extra 2 K gives around an extra 5 tons of take off weight when needed (short rwy and hot etc).

[OzFlight.net]

shakespeare,

There is an error in the system with the CASA Aircraft Register. If you have a look at VH-VBA (http://www.ozflight.com.au/rego/rego-res.php?rego=VBA) for example the landing gear type shows trycycle fixed as opposed to tricycle-retractable.

My first flight on a 700 was on the Virgin launch flight to Hobart and back, most enjoyable. Was also surprised that the seat pitch was more than I expected. I think the 800's are better again.

I would also be interested to find out how often domestic flights carry return fuel. On the short sectors of around 1-1.5 hours, do they save they much in weight by not carrying it? Is the only reason for carrying it the reduced turnaround time at each end ?

[shakespeare]

For every 1 ton of extra gas you carry, it costs around 30 to 40 kg to carry it. That is to say you will burn 30 to 40 more kg's for every extra ton. If the fuel cost differential is around 5% more expensive at the other end per flight sector hour, it pays to tanker gas around. Some one in the head shed works that stuff out.

They tanker to some ports but not many. It generally does not have anything to do with quick turnarounds.

[Dehavillanddriver]

For those that are interested, and the spotters amongst us, I offer the following.

VBA- VBL - (with a few missing in the middle due to CASA stuffup.)
20K engines - CFM-50-7B20 - no winglets and a lowish takeoff weight - low 60 tonnes 144 seats

VBM - VBS CFM-7B22 (22K) winglets, High gross weight - low 70 tonnes 144 - 138 seats depending on aircraft seating types

VOA-VOD - CFM56-7B24 24K no winglets Medium (ish) gross weight - low 70 tonnes - 180 seats

VOE - CFM56-7B26 no winglets - 177 seats, 79 tonne takeoff weight, video, airshow etc

VOF - VOJ CFM56-7B26, winglets, 177 seats, 79 tonne takeoff weight - some with video, airshow etc.

Winglets save about 500 kg (on a 800) on a ML-PH flight compared to a similar thrust NON winglet aeroplane with the same takeoff weight - numbers for a 700W about the same.

26K and 22K engines are derated whenever possible with reduced thrust then used on top - this achieves the operational objective most of the time and saves on engine wear.

All NG's are PFD/ND display rather than EFIS/MAP, and even thought there is a myriad of leasing companies the pointy ends are all configured the same - the joys of software configurable displays I guess.

All of the NG's are new with the exception of 3 - the three used ones were only a couple of months old when we got them - ex Citybird in Belgium.

No announcement as yet on a direct buy aeroplane - though press reports indicate Boeing - but no real indication from head shed as yet - as they say the fat lady hasn't sung yet - or should that be the fat mademoiselle (is that how you spell it?) hasn't sung yet? I guess we will find out in the fullness of time.

Question for the QF NG drivers - are your engines 24K or 26K?

[Columbia]

All 15 (so far) 737-800's are 26K engines with 79t MTOW. :) :)

[Cobra]

Of course you could have the best of both worlds,THE BBJ.
We have the fuselage of the 700, & the wing(&winglets) & gear of the 800. Also have the CFM56-7B26, with 77t MTOW. The new BBJ2 is based totally on the 800.
G'day to all the NG drivers DOWNUNDER.:cool:

[topend3]

thanks for the info guys, the -700 standard version seems to be very limited on the darwin-brisbane run where i have heard regular stories of bags and freight being offloaded with high pax loads to stay below MTOW, flights are capped i think with 130 pax or so. maybe this is a better route for the HGW 700 or the 800s which dj used to use regularly on this run.

any thoughts on this guys?

would the airbus do the job better?

[Dehavillanddriver]

Topend,

I would be surprised if there were regular stories of laving freight and bags behind as the LGW 700's have done it about half a dozen times if my info is correct.

The HGW 800's or the HGW 700's are the machines of choice.

With the HGW 800's particularly there would be no limitation other than the structural ones - you can load em up and go for many many miles..