Departure Procedure Performance

[AvroJockey]

Question for any performance engineers out there:

Knowing the following, how does one ensure they can meet climb requirements of ODPs or SIDs all engines operating?

• Runway analysis is for OEI, and generally differs from the departure procedure to obtain the required 121/135 requirements.
• AFM data for Part 25 certified aircraft is strictly OEI
• Your not receiving vectors, so ATC has nothing to do with obstacle clearance

To put this question in a practical way...you do your runway analysis and you are allowed to takeoff at 200,000#, but then you have a SID that requires a 800'/NM climb to 2500'. How do you know you're meeting the latter, all engines operating, and everything normal?

The reason I'm asking...My current aircraft has nothing in the AFM or any other manual thats gives you climb gradients or rates with all engines operating.

 

[scoreboardII]

It's up to your company to ensure the sids you fly can be flown and certify to you in writing that this happens.

In our jet, the OPC (laptop) can compute climb gradients in feet per mile or minute through 20,000ft to let us see if we can make the departure gradient.

 

[rjacobs]

At airports where we have to meet a climb gradient or a crossing climb for whatever reason we have additional runway specific charts showing max TO weights/configs/climb profiles that have to be flown to ensure the crossing/climb gradients can be met. If we dont have a specific runway dependent procedure, we assume that the a/c meets or exceeds the required climb gradients all engine at the max allowable takeoff weight for the runway from our regular book and our regular takeoff profile.

 

[wmuflyguy]

All Engine Operating Climb Gradient Chart in the performance section of the QRH.

 

[AvroJockey]

It's up to your company to ensure the sids you fly can be flown and certify to you in writing that this happens.

In our jet, the OPC (laptop) can compute climb gradients in feet per mile or minute through 20,000ft to let us see if we can make the departure gradient.

Thanks score. Unfortunately the company does not, but that may change.

 

[AvroJockey]

All Engine Operating Climb Gradient Chart in the performance section of the QRH.

Obviously the manufacture needs to supply this info. However, none of our manuals has all-engines-operating performance for takeoffs...AFM or FCOM. There is time and distance to climb, but only in 1000' increments...not highly accurate, but somewhat usable.

Thanks lads.

 

[jetfueljunkey]

climb chart Jepp style

http://www.jeppesen.com/documents/aviation/business/ifr-paper-services/Terminal-Text-Page-5.pdf


This is how you calculate without computer aid..

 

[AvroJockey]

http://www.jeppesen.com/documents/aviation/business/ifr-paper-services/Terminal-Text-Page-5.pdf


This is how you calculate without computer aid..

I need to know the aircraft performance...what the airplane will do before departure so you know you can meet it. The manufacturer of the aircraft I currently fly does not supply all-engines operating info in the AFM or any FCOM manual.

I was wondering how others got this data.

 

[scoreboardII]

They don't supply a distance and time to climb chart?

 

[AvroJockey]

They don't supply a distance and time to climb chart?

They do, but it's only every 1000' and the time and distance is rounded off to the nearest minute and NM. I was thinking there may be more accurate data, and something that was already given in Ft/NM or FPM. Though maybe that's how all operators get their data.