December 10, 200520 yr Can sombody please explain to me the exact procedure for a take off with out using VNAV with regards to engine settings ,accell height ect ect. Am i right in thinking that you hit THRUST mode at accell height to initiate climb thrust?thanks kav
December 10, 200520 yr >Can sombody please explain to me the exact procedure for a>take off with out using VNAV with regards to engine settings>,accell height ect ect. Am i right in thinking that you hit>THRUST mode at accell height to initiate climb thrust?>thanks >kavLook in the manual. It's under "manual flight techniques." Section 9-5. It shows takeoff with and without VNAV/Autothrottle.- John - John Drago
December 11, 200520 yr Vnav is not necessary for the initial climb sequence at all. (Actually B-29s didn't have Vnav at all either. It's a rather modern automation!)If you want to do it with the autopilot 'manually', here's one way. Set the MCP airspeed window to V2, engage the autothrottle and TO normally. Pitch will be in TOGA. Hand fly to V2. Once you're stable at V2, engage the AP and press FLCH. The AP will fly a speed on pitch climb to the MCP's airspeed window setting (or a slightly higher 'adjusted' V2). If you want to climb at a slightly faster speed, dial it in. Thrust will stay at TO power.When you are ready to begin accelerating away from your initial climb speed (~V2+10), just dial a faster airspeed into the MCP airspeed window. You will now be manually handling the FMC's automated "acceleration altitude" function from the FMC's TO page Lsk 1L. Now, just increase the airspeed with the MCP window as you wish and bring the flaps up on schedule. You are in control.When you are ready for climb power, press the THR button on the MCP Here, you are manually handling the FMC's automated "Thr Reduction" function from the TO page Lsk L3.Next, altitude will capture at the MCP's altitude window setting with ALT pitch mode. Again, this is the 'manual', non-Vnav method. Vnav would be capturing altitude in VNAV ALT or VNAV PATH.When you capture altitude with the MCP altitude window setting, pitch mode will change "ALT" and the autothrottle mode will change to "SPD." Airspeed will still be controlled with the MCP airspeed window and thrust will begin to jockey around to maintain airspeed in (now) level flight. Want to climb/descend? Dial it into the altitude window then press FLCH. Want to change speeds? Dial it into the Airspeed window. However you must have the autothrottle engaged. If not, this could turn into an E ticket ride real fast. You can still do it, but you really have to pay attention . . . consider . . . Autopilots have worked without autothrottles or years, but this Vnav mode of navigation is relatively new (20 years or so). Specifically though: Can Vnav successfully control the airplane without the autothrottle? What do you think? Here
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