Stall Identification - B737

[B737NG_Pilot]

Hello Everyone!!

From the FCOM: Flight Controls Chapter
The EFS module increases hydraulic system A pressure to the elevator feel and centering unit during a stall. Why only System A?

[R8TED THRUST]

I think it may have something to do with the B system on previous designs of the 737 causing rudder hard over's. I remember on the 733 and 735 we would go to stby rudder on the B side if we had one.

[172_driver]

The FCOM is very limited in good schematics and just throws out random words & phrases. Great for multiple choice exams but has little practical relevance.

My take on the question.. If you look at the design of the Feel- and Centering Unit and how it works, it can use either Sys. A or Sys. B pressure for feel modification. Not both. For some reason they choose Sys. A for increased feel (resistance to pull) approaching stall.

[B737900er]

Might be that system B already has a 'Heavy' load in comparison to system A that has a lesser load (systems).

[No Fly Zone]

Perhaps the "System" is not quite as smart as it thinks it is. It may help to keep your hands on the controls, trim manually until fully stable and add-in the automation one step at a time. Effective use of the method requires a full understanding of both assisting systems, but they are not that complex. That two person crew does not have to tote the knowledge of the old FE, but a far better understanding of system mechanics and behaviors won't hurt you. In normal operations, you operate the machine by the book. In a crunch, the book and the QRH become guides and the ultimate choices are up to you and your partner. Do either of you know enough enough about how it really operates to make those critical decisions? The QRH is a great place to begin and, between the lines, you may have some other thoughts. When at the end of the QRH list and still in a problem state, what will you do? Do YOU know enough about the several systems? No one expects you to be an old style FE, knowing every nut and bolt, but do you really understand the system's interactions as well as you should? This is not about your annual re qual exams, it is about understanding how your particular machine operates and, if necessary, safely landing your own tender butt. Do you know enough? Have you done the no-risk practices routines with the power, fuel and flight control systems? Have you asked the SIM instructor to set up a couple of them? That annual qual time is not just to check the boxes, but a time for professionals to learn a little more in a no-risk setting. Have YOU use your SIM time to best advantage, you have flown some of those horrible situations to a satisfactory landing. If your SIM time is simply something to be endured every year, you are not a professional and I hope that I do not have to fly with you. Pay attention to the details, boys and girls, please. A high level of knowledge and experience may treat your 'bacon' (and mine) a lot better than will upgrading to new and larger as fast as possible. And yes, given your seniority system, sitting tight for a couple of years will likely improve your Quality of Life - a lot. That seniority number will never leave you. Do you really want to change from a senior, stable FO's schedule to that of a reserve captain, perhaps with a transcon commute, just to sit in waiting? It the first year's money really worth that misery? Stay home. Finish that post-grad degree. Play with your partner and your kids. Then... when you have the big time on type, can stay home most of the time, upgrade your chops to seat 0A. Your family will respect you, your pax (and you) will be much safer and your Quality of Life will remain high. Even in your business, there are personal rewards far higher than dressing with four stripes. Please, boys and girls, learn a little more about the machine that you fly. Thanks.
Ha! Flames expected. Take your best shot and I will read. IMO, there is no excuse for a partially qualified professional - in any field. I assist at surgery on real humans - one at a time. I NEVER approach a new procedure without guidance and observation from a more experienced person - and I deal with ONE at a time. Air plane drivers deal with 10-450 souls at a time. Do I/we have some reason to expect high level, professional performance - every time you you fly? I think we do. Do you deliver that standard - on every flight? Only you can answer that one... I sure hope so.

[Centaurus]

If your SIM time is simply something to be endured every year, you are not a professional and I hope that I do not have to fly with you.

That is a harsh statement. Fact is cyclic sim sessions are very tightly controlled and leave no time to play with fancy double jeopardy scenarios such as "what if?" While most pilots would really appreciate getting more comprehensive training in the simulator - and I mean training and not blood and guts "testing" very few simulator instructors can spare valuable simulator time (if there is any time remaining) at the end of scheduled sessions to continue with systems engineering scenarios.

Not all simulator instructors make the simulator session a "Happy Hour" where the pilots leave fulfilled with the good gen. There are some that are brutalisers and have to be endured. Of course I am sure you are not of the same breed:E That doesn't mean the victims of these types of "trainers" are not, in your words, Professionals.

[Capt Chambo]

I reckon B737900er is closest.

System A only for the elevator feel and centering unit, because system B needs to be available for the auto slat function, if available, (flaps in a position where the auto slat function works, which in turn will be model specific!)

[B737NG_Pilot]

Thanks 900Er

[TURIN]

All correct.

'B' System is covering more systems including the Autoslat function.

Some good info here.

B737 Hydraulic Schematics (http://www.b737.org.uk/hydraulics.htm#Services_Supplied)

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