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B737 Single engine & use of Autopilot.

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B737 Single engine & use of Autopilot.

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Old 5th Feb 2016, 12:10
  #21 (permalink)  
 
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This seems to me a bit academic given a 10 min as opposed to 5 min MCT limit is available as a service bulletin with I believe no technical changes.
I guess you made a typo, it should say TOGA instead of MCT, but otherwise spot on. All 737 engines are certified for 10 minutes takeoff thrust (only in case of engine failure of course), as long as you pay the hefty fee to Boeing, who will then provide you with the modified AFM and relevant performance data. Absolutely no maintenance action required to switch from 5 to 10 min.

Too bad many pilots don't know this and think engine falls off the pylon after using TOGA for 5 min and 1 second.
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Old 5th Feb 2016, 13:19
  #22 (permalink)  
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Too bad many pilots don't know this and think engine falls off the pylon after using TOGA for 5 min and 1 second.

As you say the limitation is only paperwork & money, and only applies if at full power TOGA.
Let's add this to the "I didn't know that" box. And that box is bigger than many might believe: the more so because Flt Ops manuals are diluted and TR syllabi more limited. Once never learned it is easy to stay never learned. On a good day you use only a small % of a/c knowledge, and you have enough. On an average day much the same. On a bad hair day you might need more and today's apprenticeship is considerably reduced in many ways; knowledge & demonstration by the more learned.
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Old 5th Feb 2016, 14:38
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As you say the limitation is only paperwork & money, and only applies if at full power TOGA.
The 5/10 min limit for takeoff thrust is applicable any time you operate above MCT (max continuous thrust). It is not limited only to TOGA operations.
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Old 6th Feb 2016, 01:23
  #24 (permalink)  
 
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Boeing recommend that when on automatic pilot, the PF should make the AFDS mode selections. The PNF may select new altitudes if crew duties permit. Boeing fail to differentiate between two engine on autopilot and one engine inoperative on autopilot.

However, you need to take into account the situation when flying on autopilot with one engine inoperative. Here you have manual rudder, and manual thrust lever.

To expect the PF to operate the AFDS as well as adjusting manual rudder and its rudder trim, plus manual thrust lever changes, is unrealistic.

Common sense dictates in the case of one engine inoperative on automatic pilot, the PNF should operate the AFDS. Boeing seem to ignore this type of situation. So do the pedants
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Old 6th Feb 2016, 02:21
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Common sense dictates in the case of one engine inoperative on automatic pilot, the PNF should operate the AFDS.
If the PF is flying manually and the PM makes a selection on the MCP the PF can decide no to follow that Guidance (which is what makes him the PF).

However if the autopilot is engaged and the PM makes changes to the MCP then he automatically becomes the PF because he is directly "PF-ing" the trajectory of the Aircraft.
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Old 1st Mar 2023, 04:48
  #26 (permalink)  
 
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Dear fellow pilots; dear all colleagues –

Sure; at first it may not be easy to fly a commercial airliner by hand with all that is coming at you.

However: tell a baby, "walking is easy!" Yet because we can all do it - after all, we practice each day - we can talk philosophy or think about other things in addition to climbing stairs.

But because of all the autopilot flying, we now have the third, fourth generation of pilots who are completely dependent on faultlessly functioning automatic systems.

We don't admit all this to ourselves, of course, and it's certainly human to counter instead with a battery of excuses why it's not good to be able to fly at all: "Oh no - it's night time now!", "Oh no; it's been a long shift!", "Oh no; this is not the procedure!". "The airline doesn't want this," "Nobody flies like this anymore," "What's the purpose?" and so on.

And then all the crap falls out once (and usually not at 1030 in the morning, when we've had our sleep, have had our breakfast, and when the weather is perfect. But then, when it doesn't suit us at all. And the fault doesn't ask " May I happen now?" It just bangs - and then we HAVE to fly if we want to survive, whether we like it or not.

But if we don't practice this every day beforehand - dear colleagues: Let's not fool ourselves - we will end up just like Birgenair, Turkish Airlines in Amsterdam, Asiana in San Francisco, Air Asia over the Pacific, Lion Air, Ethiopian Airlines - well; you know ...).


So, is this how it should be from now on; do we want to accept that?

Very best regards -

Gunther Liebe, Dresden / Dakar
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