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View Full Version : B737 classic GO AROUND ROLL MODE


LEM
2nd Mar 2004, 17:37
Had a little argument some time ago:

Today's manuals say that in a go around the roll mode will maintain present ground track.

My question is:

Are we sure the AFDS will maintain approach ground track (which implies the ability to correct for a wind change ), or will it simply maintain wings level?


I ask that because I had the opportunity to fly the 737-200 advanced some years ago, with the same guidance (plus autothrottle, autoland, autobrakes...) as the 300, and in those manuals the wording was slightly different:

an autopilot go around would maintain wings level , and a FD go around would maintain present heading.


No big deal, you might say, but since the built in logic is in this case different, as the ability to maintain the same ground track implies getting information from an inertial reference source to correct for variable winds, I'd like to know the truth!

My suspicion comes also from having noted the Boeing tendency to simplify (probably for marketing purposes - see rivalry with Airbus) their manuals as years pass.

The older of you have certainly noticed, for example, that once, the idle ground values after the engines starting was N1=21.5 and N2=60.3, while now it's written N1=22 and N2= 60%.


So, back to my original question, are they cheating a little bit when they say present ground track ?
Isn't it simply wings level?


avioniker where are thou?