View Full Version : A320 T.O weight
Flyman35
20th Sep 2009, 11:52
what is the situation where you have to increase take off wight in A320?
Max Angle
20th Sep 2009, 13:52
You can't increase it beyond the max. certified weight although there are versions with higher gross weights that have bigger tyres and strengthened gear. Many airliners are operated at an artificially low max. weight to save on landing and airways charges and in my company it just takes a call to ops. who note the increase for charging purposes and we just load up to the max. structural weight.
Flyman35
21st Sep 2009, 04:47
I don't mean to increase it beyond the Max weight.but I have been asked a question (( what is the situation where you have to increase your weight in order to take off))
To achieve minimum inflight weight!
OK maybe thats a stupid answer, but i can think of lots of reasons to increase takeoff weight such as a need to increase payload or fuel, these answers appear too simple :)
Mutt
westinghouse
21st Sep 2009, 07:31
Taking off either on a Wet on Contaminated runway...
below certain take off weights (e.g low takeoff wieghts) the take off is not allowed.
ok guys. go ahead and shoot me down.:}
CAT3C AUTOLAND
21st Sep 2009, 07:41
Flyman35,
We have 2 variants of weight for the airline I fly for, 73500kg and 77000kgs as the maximum structural take off weight.
As has been mentioned you cannot exceed the maximum structural take off weight, however there are instances where you may be limited to a weight that is below your maximum take off weight, this is referred to as a regulated take off weight (RTOW). For example you may be at an airfield in the summer, that is 2000ft above sea level with a temperature of 30 degrees giving you a high density altitude. In this situtation you may be limited to a weight in the region of say, 69000kgs. If you have a high zero fuel weight, and need to carry alot of fuel to get to your destination you may find that loading the required block fuel would exceed this weight. In this situation you have various options.
Lets say your planned take off weight is 69834kgs and your RTOW is 69000kgs. There are a number of things you can do.
1. Simply reduce the weight, either through off loading PAX, freight, or baggage, not the desired option!
2. Increasing the RTOW by doing QNH corrections. With very high pressure you can sometimes increase the weight by 600kg.
3. Increasing the RTOW by doing a packs off take off, or leave the APU running with the APU bleed on, which will supply the packs.
4. Take credit for a headwind.
5. Reduce the fuel load. If you can meet certain criteria you can reduce the contingency fuel to 3%. Also, if the weather meets what is required in the company operations manual, you can not take alternate fuel, however you must carry addtional fuel, which sometimes saves you a few hundred kilograms.
Hope this helps.
35hPA28
21st Sep 2009, 09:04
Is that a trick question?
In an empty A320, with empty tanks, you would have to increase the weight in order to take off.
Westinghouse...... I'm guessing that you are talking about the differences in VMCG associated with various thrust ratings on contaminated runways, but this doesnt apply to the A320 as they only use FLEX.
We have no LOW WEIGHT limitation for any of our aircraft on contaminated runways, primarily because the V1 is increased to VMCG. Can you tell me which aircraft you are talking about?
Mutt
toby320
21st Sep 2009, 17:50
fliyman, thinking in some answer about your question I belive you must provide more detaills of what you are looking for, I guess at least you must accomplished with a minimun fuel related of what you are going to do an some times in order to have the aircrafth whitin the limits for cg pourposes you need to increase your weight (ballast)
but may be more info could help
toby.
BadAndy
21st Sep 2009, 18:03
The most common would be, as Toby said, for CG reasons (especially on a ferry flight). You would need to add ballast if you were flying a short-range (i.e. not much fuel) trip in an empty plane.
As for the VMCG limitations, as Mutt said, you just increase V1, so no added weight required.
Scallywag
21st Sep 2009, 22:32
Flyman35....Every aircraft has a minimum weight certified. You would have to increase your take off weight (mass) if you were below the "minimum weight" for the type in question.
Look in FCOM 3.0.1.20 (limitations). It depends on the msn, but 37,230Kg is the minimum for our A320. As empty DOM is typically around 43,000Kg it won't be necessary to increase your take of weight to achieve the minimum required mass. But on some other type of aircraft, if you have no passengers or freight you would have to increase the mass, by whatever means necessary (fuel is the simplest way) to achieve the "minimum weight" for your msn specific aircraft type.
Scally.
FlightDetent
22nd Sep 2009, 09:17
If it was a poorly phrased performance question ... you need to increase TOW value used as data entry for perf calculation when flying with CDL item :confused:
E.g. for flap track fairing the CDL says: Takeoff and approach climb limiting weights are reduced by 1180 kg.
To obtain correct performance figures for TOW of 60t pilot will increase this to 61180 kgs and then calculate using either tables or computer tool.
The true TKOF weight is of course still 60t or exactly speaking 60t minus the mass of the missing flap track.
Yours,
FD (the un-real)