I've included pics of the mechanical checklist, the paperwork, takeoff data, and load close out.
Ok kids follow me closely here. The "experts" tell me when I teach something technical teach it as simply as I can but don't dumb it down. The audience wont appreciate it if i do. Here goes.. When we take off we never just use max power. We use only enough power to safely takeoff. Why? Because the engines wear out faster, we use more fuel and the added stress on the engines make them fail more often. So we de-rate or use partial power whenever able. Using all the power is called a max thrust takeoff. Derating or using less power is called a standard power takeoff. On the mechanical you see takeoff data and bugs. Here I cross check three documents attempting to mathematically prove that we are able to perform the takeoff using standard power settings. Close out, ATIS and airport analysis or takeoff data page. Something like 98% of all engine failures occur while using max power on takeoff. See the importance? I make sure the weights are acceptable The load close out weight has to be at least lower than the ATOW. Assumed takeoff weight is simply planned takeoff weight (PTOW) plus a fudge factor of 2000 pounds. As long as my final weight is lower than this number (ATOW) then the runway and climb out weights are fine. Secondly I look at the ATIS for wind component. Basically we cannot have a tailwind component to perform a standard power takeoff. Thirdly I compare the planned temperature from the takeoff data page with the actual temp from the ATIS. The temp can be higher than planned so long as its lower than the max standard temp MTS. Here's where it gets complicated. There is a computer program loaded with data from every runway of every airport we fly to. And that data tells us what the maximum weight and temperature we can have and still safely takeoff using standard thrust from a particular runway. So if the actual temp is 26 and the max standard temp is 43, we trick the engines and tell them the actual temp is 43. And it only produces standard power. Max is available for an emergency if we need it. We just run the thrust levers full forward and the computer realizes what's up. If actual temp equals max standard temp, then we are doing a max power takeoff anyway, because thats all the power available. Jet engines prefer cold, thick, dry air. Short runways like LGA require max power.
So I make my comparisons. Are we heavier than planned but lighter than assumed weight? Do we have anything other than a tailwind? Is the temp at or below Max standard temp? If yes and the runway length allows for standard then I'll brief it like this. "we closed out at a 133,700 pounds. That's 600 above planned but 1400 pounds below assumed weights so we're good on weights. Wind is 200 at 15 knotts so that's a headwind component from runway 22L. Temperatures they planned it for 26, ATIS says its 28 but that's below the max standard temp of 43 so we're good on the temps. So the weights, winds and temps all support a standard power takeoff from runway 22L full length, flaps at 8 flexing to 43." Mouthful! And that's how we determine what power setting to use. That's all I'll say on this. There's more to flap settings etc but it's inundating at this point and not necessary. What I will say is this all falls under the category of performance and it's a ginormous class in ground school lasting a solid week and we review it every recurrent training. Every American airlines pilot must master the math, the theory and the practical application of performance or you simply don't make it through training. Sp we run the remainder of the checklists and get to the runway, switch to tower freq and when cleared we take off Uneventful hopefully!
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