View Full Version : A320 Real weight
Nick 1
16th Apr 2006, 10:21
Hi there,
does any company policy allow after T/O to check the Bus weight in AIDS gw fak page, and update the latter in the FUEL PRED page ?
Thanks.
pakeha-boy
16th Apr 2006, 17:12
Nick 1...the only time Ive ever had to do that,is in the SIM...if you load the box with all the correct #,s it shouldnt be a problem,and personally have never seen it.....I do on occasion check the GW/GWFL on the AIDS page with the Fuel pred page,and the A/C weight on the lower ecam,but as company policy,it,s not required...would be interested to find out why you would do it in the first place(as I only do it out of curiosity)/....PB
Dream Land
16th Apr 2006, 18:46
Heard of it, we don't do it, our load manifests are pretty accurate.
Watchdog
16th Apr 2006, 21:58
There is no procedure in FCOM hence such would be illegal without the manufacturer's approval. Whilst probably more accurate than using standard weights on the loadsheet, the procedure would have to be assessed etc for QA.
Gnadenburg
17th Apr 2006, 12:10
Watchdog
Airbus are telling some operators to update the Fuel Prediction page in-flight with GWFK data.
Personally, I add a knot or so per tonne of discrepancy onto Vapp. I believe the VLS+5kt Airbus requirement for the use of ATHR, has a common sense application to be on top of PFD VLS.
Newly modified Airbus aircraft have the problem addressed with FAC's & FMGC X-talking ( I think ). So the problem is really a problem- but many a Airbus folk are still happy to fly around, with ATHR ON, at VLS, with your tail just a bit closer to the ground. :uhoh:
Nick 1
17th Apr 2006, 17:21
Ok ,thanks.
Just to know other company procedures.
Cause it happen to me to discover significative difference between loadsheet data ,and real a/c weight, in particular kind of flights .
cornwallis
17th Apr 2006, 20:52
I dont know if you have ever operated an A320 towards its max weight,but in charter config(180seats) with the loadsheet perfectly legal you will invariably come out with a true weight at least two tonnes more.The climb rate is far from startling at these kind of weights which is why I always try and get some idea of true weight before step-climbing.This avoids any embarassment when atc ask you to expedite!
Escape_Slide
18th Apr 2006, 00:18
Be careful you guys. Do not do procedures NOT based on your FCOM. Your operator may have their AOC suspended. :*
Gnadenburg
18th Apr 2006, 01:37
Be careful you guys. Do not do procedures NOT based on your FCOM. Your operator may have their AOC suspended. :*
FCOM states that ATHR usage, IAE engines case in point, requires a 5kt margin on top of VLS.
Now. You are on approach and on the PFD VAPP=VLS. This could because the load sheet is out- Gross Weight FAC & Gross Weight FMGC are routinely three tonne out in my experience. Or is it the alpha probe calibration? Possibly FMGC alogorithm errors quoted at +/- 2 to 3kts.
Do you add 5kts to the VLS on the PFD or accept the 5kt requirement for the use of ATHR is OK based on perf appr page data ie: FMGC computed weight?
FCOM doesn't protect you here Escape Slide. It's your decision. Your airmanship comes into play.
Personally, I ensure the 5kt buffer on PFD VLS. Frightening the thought of being 3 tonne overwight, who knows where the c of g is, flying at VLS, with this particular problem exascerbated when landing at MLW.
Slasher
18th Apr 2006, 01:50
Our blokes on the A320 fleet regularly check GW on certain sectors where ground staff quietly throw on gifts to relleys up North. This doesnt vary more than a couple of hundred kgs but the main weight diferences are from assumed pax weights vs actual weights. Final load-sheet weights asuming standard weights will be much lower if you have say a full plane-load of slobs attending a Weight-Watchers conferance.
A few years ago was a FCOM bulletin dealing with this problem of FAC speed or FMGC speed, at the end they said that it is better to believe in FMGC computed speed instead of FAC speed even if algorithm is the same, inputs are not (ZFW for FMGC and AOA for FAC).
Of course ZFW has to be correctly inserted however a 0,3 degree diff on AOA would come up with a 3 tonnes diff on FAC speed.
I have operated 320 at high gross weight a lot of time this aircraft is over powered not like 330 but I'm not worrying about.