Autopilto problem please can you help

[speedbird002 0]

Hi All

 

Please could someone help me. I so much want to use the autopilot on the 747 to to handle the speed and Lnav but i want to do the altitude myself until i get to a certain height then let autopilot handle all of it, but my problem is when i engage AP to do Lnav and speed its ok but as soon as i move the joystick the autopilot disengages. How can i stop AP from disengaging please can you help me. I love this package but it is stopping me from controling somepart of the controls.

 

Man many thanks

 

Ian

[Rations 102]

You can not perform this combination, where the autopilot controls lateral navigation and the the pilot controls vertical navigation manually. If you want to control vertical navigation, you should use VNAV because it is more efficient and safe. You can also use flight level change (FLCH) for climbs and descents or V/S, although the latter is least preferred.

 

If you like flying manually, just follow the flight director cues, and you will not have to worry about straying off course.

 

The real aircraft is designed to disengage autopilot if excessive control column deflection is detected. Also, with FLCH/VNAV climbs, SPD mode is not used, and a target speed is achieved through adjusting pitch (e.g., if the current aircraft speed drops below the target, decrease pitch, etc.) on top of a set climb thrust.

 

Please clarify why you want to control the altitudes manually. Is it because you want to fly manually, or because you need to adhere to complex altitude restrictions? If the latter is the case, the FMC can handle almost all situations that would be possible during manual flight. If the former is true, consider flying completely manually, as it is simply not logical to fly only the vertical profile manually.

[speedbird002 0]

Hi Owen

 

I would just like to fly a little myself but not all of it. I just think it would be nice. There is no other reason as to why.

 

Thank you for your help.

 

Ian

[Rations 102]

You could try flying completely manually. It is good practice (and it would be more realistic). Perhaps you could set weather settings to calm or fair and trim the aircraft accurately after takeoff. Assign a button or key to elevator (stabilizer) trim, and adjust your trim after establishing your climb so that the aircraft holds its pitch after takeoff without any pressure on the control column. That way, you can focus on making lateral corrections, and if everything is done correctly, you will not need to worry about pitch until the acceleration at 10000 ft.

[speedbird002 0]

Thank you Owen