Max OAT

[DoItInverted]

Hi all!

Anybody knows the maximum OAT in order for an A320 to take off?

I know you can get it from the performance tables but is their one set by Airbus?

Cheers!
DII

[mutt]

It will be shown in the environmental envelope, believe that the standard is ISA+15C although you can have it extended to ISA+39.4C.


Mutt.

[enicalyth]

Yes. From the certification documents and references [including A319/320/321 FCOM, 3.01.20 P2, Seq 105 Rev.28] TO & Ldg is bounded by i) @ press alt 9000ft -45 to +32 deg C; ii) @ press alt 0ft -40 to +50 deg C, these figs I have rounded off a little. As Capt Chambo would say "caveats apply". The first of these is that it is implicit in manufacturers figures for comparison purposes (apples v oranges) that air is a perfect gas, which it isn't. You are meant to correct for the partial pressure of moisture, in other words density altitude kicks in. Read anything on thermodynamics by Rogers and Mayhew or else look up "wahiduddin" and "calculators" on the net to scale the figures from perfect gas to actual atmospheric conditions taking dew point/rel humidity into account. Next caveat is that some engine manufacturers do quote to a former FAR standard where in the absence of actual data a fictitious dew point/rel humidity was built in to accommodate some contribution from partial pressure of moisture. Final caveat [pace Chambo] you don't infringe the company rules or else find yourself working for somebody else's airline. And absolute caveat always switch the battery off on landing!!

[DoItInverted]

Thanks for the info mutt and enicalyth !

Regards
DII