Hello, I am wondering about the reasons for the difference between the autopilot in the 777 compared to the 737 and other Boeing models. When I fly the 737 ngx and I am, say, practicing t&g's I like to partially delegate to the autopilot things like the throttle and even the pitch so that I only have to manage turns at the cruise portions of the exercise, however I am finding that I cannot do this with the 777 since only the throttle is independent of the other autopilot controls so I can either have both the heading and pitch managed by the autopilot or not, and to me this is a little bit frustrating since I really enjoy having control of the heading without managing anything else. I find this somewhat odd too since it seems like a reasonable option to have implemented in such a modern airliner, so I wonder why this is so, why is the heading and pitch controls attached to one another in the 777 and not in the 737. I haven't really studied the manuals of this aircraft so I don't even know if there is an option to reconfigure the autopilot in the 777, which I really wish was the case but I haven't found anything so far. 

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I assume you're referring to the CWS (control wheel steering) AP modes on the 737. The 777 does not have these modes in real life - no other modern Boeing does. The 737 is an odd bird in the Boeing family - it's been updated so many times since its introduction in the 60s that there are a lot of old things that get left in with each new generation of the plane as holdovers because of airlines wanting to maintain comonality with the older planes in their fleet since the whole fleet doesn't get replaced at once. CWS is one of these things - it's a holdover from the non-computerized autopilots that existed in the old variants like the 200ADV. All of the more modern Boeings (747-400/-8, 757, 767, 777, 787) do not have the mode. Our 777's AP is modeled exactly as the real one exists.

 

If you ask any real life 737 pilot they'll probably tell you they never touch CWS though. The vast majority of the time, the AP roll modes in use are going to be LNAV or HDG SEL. Pilots also aren't going to handfly at cruise - that just isn't done. In the terminal area (climb, the later part of the descent and approach), sure, but not a cruise.

Guy's that I have spoken to in the past all hated CWS (Mainly L1011 drivers)    Also remember that Captains son who accidentally engaged CWS in cruise and killed himself and 74 others back in 1994.    

 

Old tech, glad it is hardly used anymore, always seemed a strange concept to me.

 

Regards

You can control pitch and heading separately in the 777 autopilot just as easily as in the 737. Just go to heading select mode, leave pitch in VNAV or FLCH. Now you can control heading directly with pitch managed as before. Or you can leave the lateral mode in LNAV and control pitch independently in VS mode. Not quite as direct as pitch CWS but it's still separate pitch and roll control.

 

Above all, please refer to the manual before saying something can't be done.