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Take-Off Performance


David Katona

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10 hours ago, Florian Venus said:

As you wrote correctly, LMC is a last minute change - in other words, there will be no new loadsheet EDNO, but changes will be recorded manually (handwritten) on the loadsheet itself.

Thankyou, Florian!  This came to me last night as I drifted off to sleep!  What a berk I am.  

Cheers,
Rudy

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UPDATE: Available at http://wabpro.cz/A320/   Hey everyone, I am planning to publish my take-off performance calculation website in a few days. Figures are based on FCOM performance cha

Hi guys, I have enabled the W & B tab on the website. Right now kilograms only! First select engine type on the Take-Off tab, as different CoG envelopes apply. CONFIG: If you select a co

Just to show you guys what I am working on for the W&B page... This is rather for people who actually care about the balance   It will show the weight and balance positions and the limits. The r

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Stu Antonio
19 hours ago, Ayush Roy said:

Has anyone found a decent method to get an accurate loadsheet for the A319 CFM? I haven't flown with it yet...really looking forward to this tool :) 

I also would love to have a working 319 CFM option, even if it's not 100% real-life-accurate. .... just give us something, David ;)

For now, I use the weight&balance of the 319 IAE also for the 319 CFM, and then switch to the 320 CFM when I calculate the T/O data. Not the best option but it's better than nothing... 

 

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Brad Zimmer

Sort of a weird question, but is there a way to have the tool determine whether we should use T/O flaps 1+F or 2, rather than having us input that in manually?  From what I have read, t/o flaps are usually determined by conditions and are usually given by a tool.  Not sure if that could be done but it would be great because I never quite know which flap setting to use given the conditions and different variables.

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Marco Serwatka
2 hours ago, Brad Zimmer said:

Sort of a weird question, but is there a way to have the tool determine whether we should use T/O flaps 1+F or 2, rather than having us input that in manually?  From what I have read, t/o flaps are usually determined by conditions and are usually given by a tool.  Not sure if that could be done but it would be great because I never quite know which flap setting to use given the conditions and different variables.

From what I know, you would always prefer Flaps 1+F as long as it gives you a flex temp. If you end up with 1+F and a TOGA setting you would step down to Flap 2. Same principle with Flap 3 (although it's not implemented yet).

Someone correct me if I'm wrong.

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Mark Lindley

Hi Dave,

 

First of all thank you for your amazing calculator.

My question...   what distance do you use for runway margin when calculating Flex and V speeds ?  Is it a fixed distance or a calculation based on actual r/w length.

Hope this makes sense :-)

 

 

EDIT..  does changing the TORA by the amount of t/o margin I want give me the results I am trying to get ?

Mark

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John Price

David - just a quick point; when I do a takeoff performance calculation in the A319 IAE, the TODS says A320-200 IAE. Is it actually giving the correct figures for the A319 or is there a fault of some kind? Just a quick heads-up, not a criticism.

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Brad Zimmer

Would someone be able to explain to me how the MTOW works and which of the 2 choices I should be selecting and how it applies when in the sim?   Also, for the seat configuration I pick, I try to simulate a 78 Economy | 42 Economy Plus | 8 First configuration for the airline I fly.  Is there a way to have that arranged in your tool and then the sim? Thanks

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Brad Zimmer
On 10/2/2018 at 12:54 PM, Brad Zimmer said:

Sort of a weird question, but is there a way to have the tool determine whether we should use T/O flaps 1+F or 2, rather than having us input that in manually?  From what I have read, t/o flaps are usually determined by conditions and are usually given by a tool.  Not sure if that could be done but it would be great because I never quite know which flap setting to use given the conditions and different variables.

 

On 10/18/2018 at 9:13 AM, Brad Zimmer said:

Would someone be able to explain to me how the MTOW works and which of the 2 choices I should be selecting and how it applies when in the sim?   Also, for the seat configuration I pick, I try to simulate a 78 Economy | 42 Economy Plus | 8 First configuration for the airline I fly.  Is there a way to have that arranged in your tool and then the sim? Thanks

Also, why to I typically get up trim sett8ngs in the 319 and never down?  I usually do random loads and cargo and it always gives me up.  

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Stu Antonio
10 hours ago, Brad Zimmer said:

Also, why to I typically get up trim sett8ngs in the 319 and never down?  I usually do random loads and cargo and it always gives me up.  

Only the amount of pax and cargo is „random“, the distribution is not. I think it will always try to distribute the weihhts as balanced and aerodynamically optimal as possible which may result in an more upward trimming. Try distribut the loads manually more to the front, it should give you the down trimming you desire. 

Stu

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Brad Zimmer

Would someone be able to explain to me how the MTOW works and which of the 2 choices I should be selecting and how it applies when in the sim?   Also, for the seat configuration I pick, I try to simulate a 78 Economy | 42 Economy Plus | 8 First configuration for the airline I fly.  Is there a way to have that arranged in your tool and then the sim? Thanks

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Stu Antonio
20 hours ago, Peter Meinel said:

@Stu You need to distribute the load more backwards to get a "down trimming"

Peter

:)yea, thats what I meant. ....

 

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Stu Antonio
17 hours ago, Brad Zimmer said:

Would someone be able to explain to me how the MTOW works and which of the 2 choices I should be selecting and how it applies when in the sim?   Also, for the seat configuration I pick, I try to simulate a 78 Economy | 42 Economy Plus | 8 First configuration for the airline I fly.  Is there a way to have that arranged in your tool and then the sim? Thanks

You asked this before, and I still don't quite get what you mean. 

17 hours ago, Brad Zimmer said:

how the MTOW works

What do you mean "how it works"? The "Maximum Takeoff Weight" or MTOW is just the maximum weight at which an aircraft is allowed to take off, due to structural or other limits. There are lots of sources on the internet where you can read more about that. But I don't see the connection to the above performance calculator right now.... 

17 hours ago, Brad Zimmer said:

which of the 2 choices I should be selecting

I don't see which 2 choices you mean. CFM and IAE? Metric and Imperial? Please be more specific. 

On 10/18/2018 at 4:13 PM, Brad Zimmer said:

how it applies when in the sim

How what applies? 

17 hours ago, Brad Zimmer said:

I try to simulate a 78 Economy | 42 Economy Plus | 8 First configuration for the airline I fly.  Is there a way to have that arranged in your tool and then the sim?

Again, I don't really get what you're trying to accomplish here.

To my knowledge, the weight model of the FSL aircraft can't be modified. The pax seating zones 0A, 0B and 0C (aircraft and tool) doesn't necessarily correlate with a specific airline seating/class configuration. You can "simulate" whatever you like, the physics don't care which weight is "first class" and which one is "economy". The forward zone may include first class and parts of economy class. It's just about the weights (anybody feel free to correct me it I'm wrong). 

Hope this helps a little, for further help, please be more specific in your questions. 

 

BR
Stu

 

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Brad Zimmer
2 hours ago, Stu Antonio said:

You asked this before, and I still don't quite get what you mean. 

What do you mean "how it works"? The "Maximum Takeoff Weight" or MTOW is just the maximum weight at which an aircraft is allowed to take off, due to structural or other limits. There are lots of sources on the internet where you can read more about that. But I don't see the connection to the above performance calculator right now.... 

I don't see which 2 choices you mean. CFM and IAE? Metric and Imperial? Please be more specific. 

How what applies? 

Again, I don't really get what you're trying to accomplish here.

To my knowledge, the weight model of the FSL aircraft can't be modified. The pax seating zones 0A, 0B and 0C (aircraft and tool) doesn't necessarily correlate with a specific airline seating/class configuration. You can "simulate" whatever you like, the physics don't care which weight is "first class" and which one is "economy". The forward zone may include first class and parts of economy class. It's just about the weights (anybody feel free to correct me it I'm wrong). 

Hope this helps a little, for further help, please be more specific in your questions. 

 

BR
Stu

 

Yes, I didn't explain this very well.  I apologize. I thought I posted a response a few minutes ago but I guess it didn't save.  I should have worded my question better, and agree it doesn't make much sense.  Long story short, in the 319 (imperial, IAE) in the W&B page it lists "MTOW Version - 68.0T and 75.5T".  I don't know what the differences are and how they both are represented in the sim.  Also, there is a section for crew (2/4, 2/3, 2/2, 2/1, 2/0).  What does that do?  Thanks.  I apologize for the previous thread!

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Koen Meier
1 minute ago, Brad Zimmer said:

Yes, I didn't explain this very well.  I apologize. I thought I posted a response a few minutes ago but I guess it didn't save.  I should have worded my question better, and agree it doesn't make much sense.  Long story short, in the 319 (imperial, IAE) in the W&B page it lists "MTOW Version - 68.0T and 75.5T".  I don't know what the differences are and how they both are represented in the sim.  Also, there is a section for crew (2/4, 2/3, 2/2, 2/1, 2/0).  What does that do?  Thanks.  I apologize for the previous thread!

a lower MTOW results in a lower airport lading charge and takeoff charge as those look at the MTOW of an aircraft. that's why some airlines lower the MTOW to avoid high airport charges. in the sim, only the max TOW is referenced. the 2/4 or other option is how many crew is onboard, a general rule of thumb is per 50 passengers one cabin attendant and 2 pilots of course.

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Stu Antonio
16 minutes ago, koen meier said:

the 2/4 or other option is how many crew is onboard

right, and I may add: X(flight crew)/X(cabin crew).

On a different note, this tool - as many pointed out - really could use some manual or tutorial. 

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Stu Antonio

While we're at it, I think I pretty much understand every part/value/field of this tool, except this one:

What is (in this case) "2450" telling me?

image1.jpg.b97cc60e274fa1854644035067f0711e.jpg

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Riccardo_Parachini
While we're at it, I think I pretty much understand every part/value/field of this tool, except this one:
What is (in this case) "2450" telling me?
image1.jpg.b97cc60e274fa1854644035067f0711e.jpg


To make it simple, as you have headwind you have better performance, so depending on how much headwind you have “more” runway to take off. So for instance if you have a 2000m runway and with zero wind you are performance limited, with 10kts headwind you could be able to take off from that runway. So your performance are as you’d be taking off from a longer runway.
The opposite applies with tailwind.
Hope this makes sense, I know it’s not a by the book definition :).


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Stu Antonio
24 minutes ago, Riccardo_Parachini said:

 


To make it simple, as you have headwind you have better performance, so depending on how much headwind you have “more” runway to take off. So for instance if you have a 2000m runway and with zero wind you are performance limited, with 10kts headwind you could be able to take off from that runway. So your performance are as you’d be taking off from a longer runway.
The opposite applies with tailwind.
Hope this makes sense, I know it’s not a by the book definition :). 


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That makes perfect sense, thanks, I got it! :)

Is ist possible to determine the stop margin from those values? 

 

 

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Swadeep Chansrichavala

I love this tool but the values here are very different to the auto calculation by FMGS. So i assume stick to this and throw the auto calculation out the window? Would love it if there's optimum flaps settings too.

Thank You!

Swadeep

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Stu Antonio
6 hours ago, Swadeep Chansrichavala said:

I love this tool but the values here are very different to the auto calculation by FMGS. So i assume stick to this and throw the auto calculation out the window? Would love it if there's optimum flaps settings too.

Thank You!

Swadeep

This has been discussed before, the auto calculation doesn‘t take all relevant factors into account (ie runway length, wind and baro pressure). 

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Swadeep Chansrichavala
1 minute ago, Stu Antonio said:

This has been discussed before, the auto calculation doesn‘t take all relevant factors into account (ie runway length, wind and baro pressure). 

Noted. Thanks for reply. Will use the web based takeoff performance calculation. 

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Stu Antonio

@David Katona 

Hey David, just wanted to kindly ask if you have some sort of routemap or a current state of development of your tool?

are you still working on it, on a 319-cmf or even 321-versions? Do you have future plans with this tool, like an mobile app, an improved/redesigned user interface or new functions?

Or is this project currently unattended and on hold/finished?

BR

Stu

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Stu Antonio
1 hour ago, Lefteris Kalamaras said:

Hello @David Katona,

just a heads-up - let me know when have a free minute or three :) - I'd love to chat with you (I've sent you a PM too).

Thanks!

Yea, join forces! :) 

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Chirag Geiantilal
On 10/31/2018 at 11:44 AM, Stu Antonio said:

While we're at it, I think I pretty much understand every part/value/field of this tool, except this one:

What is (in this case) "2450" telling me?

image1.jpg.b97cc60e274fa1854644035067f0711e.jpg

What is the mean of [+3] on that field?

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Stu Antonio
1 hour ago, Chirag Geiantilal said:

What is the mean of [+3] on that field?

That's the actual wind component in direction of takeoff. Take a look at the METAR, test different runways and you will understand.

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Chirag Geiantilal
On 10/31/2018 at 11:44 AM, Stu Antonio said:

While we're at it, I think I pretty much understand every part/value/field of this tool, except this one:

What is (in this case) "2450" telling me?

image1.jpg.b97cc60e274fa1854644035067f0711e.jpg

How is 2450 calculated?

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Riccardo_Parachini
How is 2450 calculated?


There are some tables in the FCOM and for each runway. Basically you are taking off from a 2428 runway but with that headwind component is like taking off from a 2450m runway. So you can use a higher flex. The opposite with twc


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Chirag Geiantilal
1 minute ago, Riccardo_Parachini said:

 


There are some tables in the FCOM and for each runway. Basically you are taking off from a 2428 runway but with that headwind component is like taking off from a 2450m runway. So you can use a higher flex. The opposite with twc


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Yes, but there's any formula to calculate it?

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Riccardo_Parachini
Yes, but there's any formula to calculate it?


For sure there is. But honestly I’m not really interested in that. The tables write that for every 10kts tailwind you loose 100m runway (I’m guessing as I have not the tables in front of me), my job is simply applying that in the safest way possible. Sorry, that was the long answer :).
In short there is but I’ve only the results, the tables :)


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Koen Meier
4 minutes ago, Chirag Geiantilal said:

Yes, but there's any formula to calculate it?

It is a table which you follow from left to right and with some interpolation between figures you get an end result.

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Riccardo_Parachini
  Minimum runway length (with wind correction) for flaps F2 is 1500 meters or 4921 feet! 
Note: tailwind reduces runway length!) [mention=15218]David Katona[/mention] tail wind increases runway length not reduces.


In what sense increases runway lenght?
I see it works correctly as with tailwind it’s like you are reducing your runway available ...


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Koen Meier
15 minutes ago, Riccardo_Parachini said:

 


In what sense increases runway lenght?
I see it works correctly as with tailwind it’s like you are reducing your runway available ...


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12 minutes ago, Alexandre Kubatko said:

It increases runway length needed so it decreases the runway length. I see no mistake either here.

Your both correct but I find the phrasing of it a bit weird. This could be clarified better for people who don’t understand all the different distances on a runway.

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Hi everyone,

@David Katona many thanks Monsieur (Sir) about your web-based calculator, I'm considering PayPal donation for your stuff! ;) (edit: donation was done this night).

I have just one question: in "Take-Off" tab, what's ATOW accronym is meaning exactly? (in fact, it's not clear in my mind - I'm new A319-X/A320-X user, and unfortunately I can't find ATOW on the net). Thanks in advance.

A319 CFM will be great when implemented, in order to cover all FSLabs Airbus.

Thanks again David!

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Koen Meier
5 hours ago, DomiKamu said:

I have just one question: in "Take-Off" tab, what's ATOW accronym is meaning exactly? (in fact, it's not clear in my mind - I'm new A319-X/A320-X user, and unfortunately I can't find ATOW on the net). Thanks in advance.

ATOW is actual takeoff weight.

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