TO performance questions

[ricfly744]

Dear all,

Do you have in your performance calculation any correction or table to account for the efect of HUMIDITY for TO performance? We know there is a performance degradation in saturated air. I heard SIN has something as it is very humid in Singapore.
I also would like to know if your SOP requires a V1 callout a few knots before V1 to account for a delay in recognition and action. If so, how many Knots?
Thanks for the info.

Rick

[mutt]

No and No......

Mutt

[stiffwing]

Actually, no and yes..
Our SOP's require the V1 call to be completed by V1, not at V1.
Interestingly, a number of our a/c have automated V1 calls.. these automated calls seem to announce somewhat earlier than a pilot would call V1, imho.

[Denti]

No and yes. V1 is called automaticly and at least on the boeing fleet the automatic V1 callout is scheduled to be completed by V1 as mentioned above, typicly it starts at V1 minus 3 to 5 knots.

[Old Smokey]

NO and NO.

As IGh has pointed out, 80% humidity is already "built in" to the certified performance data. No further pilot input is necessary, or mandated. No further input is required by the "user" Performance Engineer who manipulates the AFM data.

With respect to early V1 calls, it may be beneficial for the Accelerate-Stop manoeuvre, but decidedly dangerous for the "GO" case if V1 is Vmcg limited...... NEVER NEVER mess with Vmcg!!!:eek:

Regarding the Automated V1 calls, I will be watching the V1 bug with eagle eye on the ASI on my next Takeoff, to see exactly when the "robot" calls it. II DO monitor it closely in any case in case the automated call doesn't come, and cannot recollect any occasion on the B777 when the call was not "spot on".

Regards,

Old Smokey