Hey ya’ll, I’m on my way to CDG on a 787-10… Just got to my initial cruise alt. of 320. I don’t know if I’m at an efficient power setting and/or Mach num. (I’m at Mach .8 at this moment). So I’m interested if you have the knowledge of the 787 most efficient Mach num. & at what should the (estimate) power setting be at cruise? (Weight is 57%).
Thanks.
Hi! Below, I’ve linked a thread on cruising speeds and fuel burns as well as a step climbing tutorial. As long as your engines are not being worked to the max (N1 is not too high), you should be good to keep climbing. For your aircraft, the cruising speed is mach 0.87, as per DeerCrusher’s tutorial. Boeing say 0.85 though. So, increase to that speed. If you’re N1 is too high at FL320, stay there to burn off some fuel, then keep climbing until eventually you burn enough to reach your desired cruising altitude. For 57%, I’d guess that you’re good to go to FL360 or even FL380.
If you’re N1 is in the 90% range, I’d recommend to stay where you are until it gets down to the 80% range.
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Think I’m about to pass you look to your left:). Thanks for your help!
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Happy to help! Safe flying over there! ;)
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Cruise speed for the 787 is Mach .85, according to Boeing.
https://www.boeing.com/commercial/787/by-design/#/all-model-performance-summary
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Yeah, looks like it, my bad. I got the 0.87 from DeerCrusher’s tutorial but the plane’s manufacturer is probably the expert.
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Ah ok. lol.
M.85, and at 57% load you should be at FL350 or FL360 depending on your heading, and if you’re going East climb to FL370 soon.
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Cruise for 787 is M.85
I don’t think the 787 is really known for stalling out. Although the AOA is quite high (because the cruise flap thing is not in IF), it can actually go crazy fast if you pull full thrust on casual
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