Airplanes Characteristics for Airport Planning AC...

[Robini]

Hi everyone on PPR,
Problem here again...
I was and checked the ''Airplane Characteristics for Airport Planning AC''
for different airbus types...

And above the diagram i can clearly see a text, that says following:

NOTE: THES CURVES ARE GIVEN FOR INFORMATION ONLY THE APPROVED VALUES ARE STATED
IN THE ''OPERATING MANUALS'' SPECIFIC TO THE AIRLINE OPERATING THE AIRCRAFT

What are they meaning with this?
Aren't these numbers correctly or what?


//R

[Spitoon]

My guess would be that whatever data are given are those that will apply if the aircraft is operated according to the manufacturer's instruction manual. But pilots don't always follow the manual......

[Robini]

''But pilots don't always follow the manual......''
:ugh:
Of course they do, if they wouldn't and just taking off without checked with the manuals you WILL get kicked from your job...You are not allowed to play with the safety..........You can't get away with that, there are too many ''investigaters'' out there...

My question was moore like WHY they seem to have different numbers?

[mutt]

Robini, calm down, there are many ways to operate an aircraft, all of them will be in the AFM, but not necessarily the airport document. The reference that you found is common in many "NON CERTIFIED" manuals, its a liability issue.

And believe it or not, sometimes even the certified Manuals/Software is wrong!

Mutt

[Robini]

Ok, well some of them may have a little wrong then...
But if you look at this ex.
ISA RWY required (Airport charestic): 3100 m
ISA RWY required (SAS A330 captain told me): 2800m

But the dif is 300 m...and thats quite alot!!
Is that possible that it can have been 300 m wrong?

Thanks mutt

[Henry VIII]

I make an hypothesis.
The manual you are talking about is a general acft type manual, they suggest to refer to specific AFM because AFM only consider the exact acft you handle (e.g. type of engines, brake type, aerodinamic update, whatever).SAS A330 captain told meVerify the source and check again the calculation.

[Robini]

Well, the information i got at hands...is available here:
Technical Data Airplane Characteristics Consult and Download (http://www.content.airbusworld.com/SITES/Technical_Data/html/800x600_AC_main.html)

Look at A330 then you will se that A330 RR Trent 772B requires following:
230T: 3000 m (about 9800ft)
233T: 3125m (about 10250ft)

The engine is RR Trent ( as i wrote above)...Doesn't matter A332 or A333, the dif is so small.

But it still fascinating me that it maybe can be 300 m differens, i mean thats to much.isn't it?

[barit1]

The AFM, prepared by the mfr, always seeks to convey the best possible perfomance, to market the airplane in its best light. But this performance may be dependent on some unusual parameters or techniques.

Often an airline's engineering dept will determine not all of that AFM performance is necessary for the airline's route structure, and will issue simplified performance charts, less optimistic than the mfr's charts, but based on more standardized processes and techniques.

So it's important to differentiate between AFM and operator charts in questions like this.

[Spitoon]

Of course they do, if they wouldn't and just taking off without checked with the manuals you WILL get kicked from your job...You are not allowed to play with the safety..........You can't get away with that, there are too many ''investigaters'' out there...Thank you, Robini. I've only been in this business for 30 or so years. I see I still have a lot to learn.

[Robini]

Spitoon: Well, there are NO ONE in this branch that knows everything :ok:


Anyway, back to topic...
Still quite (or very) confused about this. So if you want EXACTLY correct info you need to turn to the AFM?
Well, probaly these 2800 m are correct if no A330 captain comes and give me moore different infos :ok: then i guess my head will X-plode...:eek::eek:

[Robini]

''Verify the source and check again the calculation. ''

Well now my approvments is only this message..But i hope he isn't a liar :ok:


''Hi

Sorry for the late reply....
MTOW A330-300 (233 tons) in standard atmosphere requires appr 2800 meters at sea level.

Rgds''

300 m can't get out of my head...Anyone here that knows the answer?
Please post it, i could do everything to get it :ugh:

[mutt]

Hate to tell you but neither answer is right......... :):)

A330-243 ISA/15C/SL
Configuration CONF3
Weight :233000.kgs

TOD OEI 1.15 TOD AEO
2506M 2110M

Gotta love technology :)

Mutt

[Henry VIII]

One more hypothesis.
Robini, may be that both your friend and mutt use a LPC way to calculate the figures.
This gives more accurate interpolation of the graphs giving more "performing" results.

[Robini]

Hello mutt,
Thanks for your figures, i really appreciate them :}
Maybe there ARE a differens between the A332 and A333?
I actually don't know how the dif whould be, maybe something to do with CG and
that the A333 has a very long fuselage?
I mean maybe 2500m for A332 and 2800 m for A333?
This subject :ugh::ugh:
//R

[mutt]

I mean maybe 2500m for A332 and 2800 m for A333?

Nope, I can get the same for the A333......

Part of the trick lies in what Henry VIII said, the software allows multiple mthods of calculating including first principle and polynominal (Difference between these two alone is 2,000 kgs in this case). Airbus have some unique ways of optimizing aircraft performance, hence the reason I told you to find the book "Airbus - Getting to grips with aircraft performance" and study it.

Good Luck.

Mutt

[Robini]

Now i checked it out...
AEO= All Engines Operating
OEI = One Engine Inoperative

Then you need 2506 m...thanks mutt :}
//R

[Robini]

One question only, why do you have Airport plannings sheet like this one then?
I mean when they are far away from the real world....:(

[Henry VIII]

1-1 Purpose
The A330 AIRPLANE CHARACTERISTICS (AC) manual is issued to provide the
necessary A330-300 and A330-200 basic versions data which are needed for
airport operators and airlines for the accomplishment of airport facilities
planning.
My interpretation says that this kind of books are referred to a generic acft, for specific situation you have to refer to the company docs as like as to company SOP to calculate and/or establish perfomance data.

[Robini]

Henry VIII,
Im with you so far, it's just that i'm still shocked that the dif can be 620 m!!!!
IT'S AN ENORMOUS DIFFERENS :eek::eek::eek:
Exact numbers is maybe +-50 for me...not -600!!
But thanks!:ok:

But problably it's Robini that's the problem now :ugh::E

[mutt]

Its a case of using the right tool for the job, and the airport characteristics isnt the tool for aircraft performance. In fact i have never even seen it for the Airbus!

Mutt

[Robini]

mutt,
Thanks for answer my confusing questions:E:E

Anyway, you have any figures for 0C and 30C ?
It would be very interesting to have :D


//R

[Robini]

Well of course i'm not happy when i just got swindled.....
But you're maybe a little bit right, it's possible to express yourself on a little bit ''cooler'' way....

Anyway, you can help me with the last question?

//R

[Big Bad D]

Robini, what makes you think that you have been swindled??? As others have already said, you need to use the correct documents for their correct purposes.

It is not the intent of an airport characteristics manual to provide a full and certified definition of performance of specific aircraft models and configurations. The data is only intended to be generic for basic airport (not aircraft operations) planning purposes.

If you didn't have such an unfortunate attitude then perhaps more helpful information would be forthcoming!

[Robini]

yep...........

[enicalyth]

The airplane characteristics documents are intended for airport planners.

Quote:

Airplane Characteristics for Airport Planning -- Boeing provides a variety of documents that provide airplane characteristics data for general airport planning. Sections within each document include airplane description, airplane performance, ground maneuvering, terminal servicing, operating conditions, and pavement data.

As aircraft are not bought off the showroom floor and because neither CCompany A nor Company B have any intention of being "freer" with their material than they have to be the "characteristics" serve that general purpose and no more. In both large companies.

Now if you want a better analysis tool I suggest you google lissys piano and Dr Dmitri Simos. For around 4,000AUD you can purchase software for one individual airframe and it comes close (but still no cigar) to the software and manuals supplied on contract by the manufacturer to the operator.

Now having got that off my chest that airplane characteristics for airport planning are exactly that and not an authority for any phase of flight planning .

"The child is father of the man" Robini. Grow up.

[Pugilistic Animus]

Robini, if I were you I'd feel grateful that a forum were available for me to ask questions openly---I see that you'd rather spend more time lecturing the professionals about their jobs than learning as soon as you post you sign off---that signifies to me that you are NOT trying to learning anything

real professionals have worked for years gaining the requisite knowledge to succesfully perform their jobs to a very high standard---and have spent many countless hour studying and learning---and still continue that process
I hate the break it to you but you not asking difficult or profound questions in fact they are way too vague and non-specific to have any meaning in a larger technical context---when you shell out many thousands of dollar and you have a reason the OEM will give you all you want---now either payf or it and I doubt you'd want to--- or quieten down and accept the guidance given here gracefully

Now, I'm sure you have many gaps in your knowledge this is not the way to become a pilot or an engineer---:= it only alienates you and you become an arrogant ass---and the mountains don't know you---

your conduct recently has become disgraceful and I'm disapointed:(


Lester:E

[Pugilistic Animus]

thanks for the advice:zzz:

but I think I do OK for myself:}

[mutt]

Robini, quit while you can, come back in a few years when you are more mature. It appears that you are incapable of participating in a forum at this level.

I have tried to be helpful and have participated in this thread from 5 different cities, 3 different countries and 10 different time zones, but thats it, enough is enough.

I would suggest that you try airliners.net

Mutt

[john_tullamarine]

.. never fails .. every time I am away for a few days, something goes off the rails.

Robini .. we accept your enthusiasm and applaud your interest in aviation.

However, you probably would be well placed to accept that quite a few of the folk here are acknowledged experts in their particular fields. The resource available to readers is significant .. and for free.

A wise man uses it gratefully and politely.

[V2-OMG!]

I am "enthusiastic" but ignorant. Is there a manual entitled, "Desirable Characteristics of Those Planning to Post on PPruNe"?

Until then - this "wise woman" will glean her information gratefully and politely. :O

[john_tullamarine]

I guess it doesn't hurt to revisit the expectations from time to time ..

I am "enthusiastic" but ignorant.

This is a wise statement and applies to us all .. with the proviso that ignorance is selective and complete professional knowledge, as a practical goal, went out shortly after the Renaissance.

PPRuNe is unusual in that there is a very wide range of expertise represented within the group. We have newbies through to university full professors with quite a smattering of PhDs of various ilk sprinkled throughout. PEs and the like abound as if grains of sand on the beach, etc.... Experienced professional pilots, of various disciplines, comprise the great bulk of the group.

Is there a manual ..

Unfortunately, not. The only "rules" in this part of the sandpit are

(a) threads need to have, at the least, a tenuous link to aviation .. and usually we manage to interpret that in a very pragmatic way.

(b) we require a modicum of civility. We are very tolerant but, on occasion, we do need to exercise some degree of censorship, distasteful as that might be. This is best interpreted as "play the ball, not the man". Note that we don't suggest that argument should be watered down in any way .. only that it should be rational and civil.

(c) sideline administrative issues are taken care of reasonably transparently .. things like no naming folk or organisations (especially in an adverse manner) unless the information is very definitely public domain. Even then, often we will edit such information out on the basis that it is not generally relevant to tech log and, in general, is distasteful.

.. and, that's about it. Fortunately, the great majority of folk who frequent tech log are reasonable and pleasant people.

Until then - this "wise woman" will glean her information gratefully and politely

One can only concur with such an approach.

[V2-OMG!]

......ignorance is selective and complete...

Exactly. It should never be haphazard.

In the course of my writing, I am often faced with an ensemble of technical research which would be impossible to comprehend completely. My only tool is one of abstraction or selective ignorance -- a grope for the parts which will will congeal into some form of acceptable totality.

I do enjoy and appreciate the plethora of technical information which is freely accessible on this forum.

Fortunately, the great majority of folk who frequent tech log are reasonable and pleasant people.

One can only concur with such an assessment.