maximum range-airbus comparator

[alexban]

could someone explain,from this data's http://www.airbus.com/en/aircraftfamilies/productcompare/ ,how is it,that with the same max fuel there is a different max range for different types? (you should select aircraft 1,2,3,4 ---318,319,320,321 )
I would've thought that the heavier one will go the shorter distance.They have the same wing,Mmo.
How is this max range calculated? And ,from that example,what is the max range for the 318? in NM..
what is range (w/max passangers) .....2700 (5,950) km ? (on the 318)
brgds

[Gary Lager]

Every aircraft design is a compromise between conflicting factors - wing thickness versus structural strentgh, for example.

Derivatives like the 319, 318 and 321 result from changes to a design which has been carefully optimised, so it is likely that performance in some areas will improve at the expense of degradation in others.

A specific suggestion for the difference in range you mention: perhaps the shorter fuselage allows less stabiliser balancing arm, so the tail downforce has to be higher. This might account for it, but I don't know for sure.

The website shows pretty simplified data - my point is there are many other factors which influence performance apart from wing design and overall weight.

[enicalyth]

Performance standards for ONE model.
[They are not necessarily the same - see above]
Nominal not airline specific
Take-off performance
SITA runway data used
Airport temperature ISA + 20
Zero wind considered
Calculations have been performed for Wet conditions with dry check.
En-route performance
Track distances : GC distances + 5%
En-route and diversion winds : 85 % annual reliability
Winds in cruise reduced to 70% for climb and descent
ISA+10 en-route temperature
Taxi times and speed schedule:
Taxi-out 10 min / Taxi-in 5 min
Cruise M0.78
Reserve fuel policy for standard profile
En-route allowance : 5% of trip fuel and diversion fuel
Diversion to xxx defined airport at LRC
30 min holding at 1500 ft above alternate
Reserve fuel policy for isolated profile
En-route allowance : 5% of trip fuel and diversion fuel
Diversion reserve : continued cruise for 120 min
30 min holding at 1500 ft above destination
Fuel density
d = 0,803 kg/l
Examples (Note both less than 75.5MTOW)
A319-100 with V2527M-A5, MTOW 75,5 t, SEPCARBIII - BSCU Std9 or EM2.
Payload 124 Y.
Standard profile outbound to xxx [name withheld].
CAA profile isolated inbound xxx [ditto].
ISA+10 en-route temperature.
Wind : 85 % annual reliability.
Distance 2324nm
Wind -7
FL 330/370
Crz M 0.78
TOW 71692kg
LW 58822kg
Block Fuel 13065kg
Cont Fuel 851kg
Res Fuel 5182kg
Block Time 05:37
P/L Pax 12152kg (124 @ 98)
P/L Cargo 0kg
Profile Isolated (ie Island Reserve)
Distance 2270nm
Wind -48
FL 350/390
Crz M 0.78
TOW 69418kg
LW 56152kg
Block Fuel 13462kg
Cont Fuel 738kg
Res Fuel 2532kg
Block Time 05:59
P/L Pax 12152kg (124 @ 98)
P/L Cargo 0kg
Profile Standard
Take-off A319-100 with V2527M-A5. SEPCARBIII - BSCU Std9 or EM2.
MTOW=75.5t.
SITA runway data
Airport temperature ISA+20.
Zero surface wind.
Wet with Dry Check.
Landing A319-100 with V2527M-A5. SEPCARBIII - BSCU Std9 or EM2. JAR.
MLW=62.5t.
SITA runway data
Airport temperature ISA+20.
Zero surface wind.
Wet with dry check.

PS wind tables are based on statistical reliability therefore what you get on the way out is not the inverse of the way back. You are not dealing with a real specific wind but a specific scatter of probabilities.

Hope there are no typos.

Best Rgds

The "E"