I just seen a company SOP where the pilots use 800 AGL for Accelaration altitude and 3000 AGL for CLB Thrust.

 

Odd but everything is for a reason, can anyone state why?

 

 

Odd but everything is for a reason, can anyone state why?

 

Because that's what the company deems to be "safe" and "correct." I wouldn't waste much time trying to make sense of SOPs. They vary too much, and can occasionally be based on the most random things.

 

Also, those two altitudes are commonly used in the NADPs anyway.

 

Conversely, explain why you use the altitudes you use. The reasons you cite would likely be their reason for using the altitudes they use.

I'm not mix and matching SOPs i came to understand its easier and less work to just stick to Boeing standards. Simples lol

 

Just odd its the other way about. But like you mentioned kyle loads of times aviation isn't rigid and you can perform whatever you like but in a safe manner.

As Kyle says, the reasons could be many and varied -- anything from what the beancounters say is the most efficient profile, to what the chief pilot used to do, to 'we've always done it this way'...

 

Low acceleration altitudes, generally, are moneysaving -- if you clean the aircraft up more quickly you'll save a few kilos of fuel, which might be insignificant on one flight but become significant when added up across hundreds of aircraft operating thousands of sectors.

 

SOPs such as these will generally, in my understanding, be overridden by airport-specific procedures where they exist.

Low acceleration altitudes, generally, are moneysaving

 

Yes very true, i also read somewhere that doing a NADP1 uses more fuel because your taking longer to accelerate to higher alt where you burn less fuel as the main point is getting high and into that tailwind.

 

 

SOPs such as these will generally, in my understanding, be overridden by airport-specific procedures where they exist.

 

Yeh another true statement, thats why i always read my general notices on that particular aerodrome.

 

I have a question guys-

 

After establishing Electrical Power Up (SP) do you then set the IRS mode selectors from OFF, to NAV once that section has been done. I know it says it in the FCOM. Or can you start the IRS straight away once the BAT has been placed to on and power restored?

After establishing Electrical Power Up (SP) do you then set the IRS mode selectors from OFF, to NAV once that section has been done. I know it says it in the FCOM. Or can you start the IRS straight away once the BAT has been placed to on and power restored?

 

Not exactly sure what your question is, but I'd align the IRSs anytime after I have AC power available, be it APU or external. I wouldn't exactly align them on battery power, and really the preflight takes long enough to get the alignment done sometime in between so there is no need to rush right after you flipped the battery on.

 

After establishing Electrical Power Up (SP) do you then set the IRS mode selectors from OFF, to NAV once that section has been done. I know it says it in the FCOM. Or can you start the IRS straight away once the BAT has been placed to on and power restored?

Vernon

I would suggest you put this question in a new topic. Bringing this up in a thread about acceleration heights and climb thrust just confuses people who are trying to find answers to a problem like the one in your question.

Not exactly sure what your question is, but I'd align the IRSs anytime after I have AC power available, be it APU or external. I wouldn't exactly align them on battery power, and really the preflight takes long enough to get the alignment done sometime in between so there is no need to rush right after you flipped the battery on.

 

Well during the SP Electrical Power Up and after placing the BATTERY switch to on you then work down the list and if external power is needed, GRD POWER switch - ON

 

Or if APU power is needed, start the APU.

 

After connecting one of these power sources to the AC Transfer Busses, can you then start the IRS alignment?

 

Thats what my question is.

Vernon

I would suggest you put this question in a new topic. Bringing this up in a thread about acceleration heights and climb thrust just confuses people who are trying to find answers to a problem like the one in your question.

 

Yeh true

Yes, that's basically what the procedure says. The prelim preflight assumes there is power, so once that is done you can align the IRSs. Something that's not in the NP but many do would be to finish the position entry in the CDU right away with the switching on the IRS MSU, even though it's not explicity stated in the NP.