August 26, 201114 yr I was happened twice in cruise,and i found cause is"Current conditions result in a maneuver margin less than specified." in FCOM2.But i still can't get understand....Has anyone can explain detail..? And i always use ASE to get weather,so i was thinking could be by weather data change in cause. Thanks a lot. Jia-Hsing Fu
August 26, 201114 yr I have only had this warning when you exceed your max calculated cruise level calculated by the fmc for your aircraft weight. Jason Paver
August 26, 201114 yr All you can eat ? ed: oh now I know what you mean.. sorry Regards, Max (YSSY) i7-12700K | Corsair Vengeance LPX 64GB 3600MHz DDR4 | Gigabyte RTX4090 24Gb | Gigabyte Z690 AORUS ELITE DDR4 | Corsair HX1200 PSU
August 26, 201114 yr It's called "coffin corner" for a reason :) Overspeed buffet and low speed stall speed become the same speed... and you're in trouble. Omar Josef 737/757/767
August 26, 201114 yr I was happened twice in cruise,and i found cause is"Current conditions result in a maneuver margin less than specified." in FCOM2.But i still can't get understand....Has anyone can explain detail..? And i always use ASE to get weather,so i was thinking could be by weather data change in cause. Thanks a lot.The FCOM Vol 2 page 1133 says !!!! "" Bring the airplane back within the operating envelope. "" Is your speed or altitude too high ??? Frederic Steiner.
August 27, 201114 yr A lot of parrotheads chartering flights to a concert... Oh wait, that's a Jimmy Buffet Alert! Kevin M. Manley
August 27, 201114 yr Author @JASON I was set cruise altitude is by FMC calculated result.So i not get to high altitude. @Omar Before get buffet alert ,i was in stable cruise,then get buffet in the short time.I notice IAS drop down to yellow are.And buffet has two condition is overspeed and low speed??(Thanks you share this page)@Frederic I was meet "something" causing my IAS was drop down.And my speed and altitude is normal before.I just don't know what is reason....i know is low speed to receive alert message. @Kevin I was eat launch before,this alert could be for other people... Jia-Hsing Fu
August 27, 201114 yr In the first pic you have no autopilot engaged. ??? In the second pic CWS P is the pitch mode.You are climbing in to a stall !!! Are you flying the plane manually with LNAV and VNAV engaged ? Buffet Alert would be normal in this case.You are about to stall the plane. Frederic Steiner.
August 27, 201114 yr Author @FredericIn first pic,i was disengage AP,then i try to control to stable.Second pic i was forgot circumstances....No i was always receive buffet in AP control condition.Maybe i fly more times try to find out the reason. So far i know if get overspeed or stall speed in the more high altitude then will receive BUFFET ALERT. Jia-Hsing Fu
March 21, 201313 yr If your speed is within the yellow zone, your airplane might loose aerodynamics and stall at a higher airpeed, within zone add flaps to maintain altitude or descent to lower altitude. Or just research it in internet to find answer/solution. It only took me me one minute to find answer for you same problem. Go back to props!!! Some people....
March 22, 201313 yr Do you use weather programs like active sky or similar? If yes it could be the cause of your troubles if you don't set smooth change in weather conditions. Regards Andrea Daviero
March 22, 201313 yr If your speed is within the yellow zone, your airplane might loose aerodynamics and stall at a higher airpeed, within zone add flaps to maintain altitude or descent to lower altitude. Or just research it in internet to find answer/solution. It only took me me one minute to find answer for you same problem. Go back to props!!! Some people.... Leaving aside the unfriendly and unhelpful tone, this is not correct. If your airspeed falls into the yellow buffet zone you are not likely to "lose aerodynamics" and stall at a higher airspeed. Your stall margin is decreased, but your stall speed is unchanged. You certainly should not add flaps in a high altitude cruise situation. An aircraft can never lose aerodynamics unless it flies into a vacuum, i.e. at the edge of space. This happened to X-15 pilots but isn't likely to happen in an airliner. Sure people can google answers rather than ask questions you might regard as beneath you here. But it seems your google search wasn't very informative. The whole point of this forum is to get relevant and informed advice. If you don't know the answer, don't reply. Certainly don't resurrect an old, already answered, thread to add inaccurate information.
March 23, 201313 yr WOW - You dug up a post from 2011 just for that - and thats your first post.. amazing Brent Lewis
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