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Common misunderstandings B737

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Common misunderstandings B737

Old 25th Oct 2011, 13:46
  #21 (permalink)  
 
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Going overboard with superfluous confirming switch selections. The FCTM states the essential confirmation items and this now appears in QRH.
Imperious "support" calls such as SPEED in a loud voice even though speed is within company tolerance. Usually done by nervous nellies as point scoring .

PNF "hovering" with hand creeping toward gear lever in eager beaver anticipation of the PF calling "gear up". Ditto flap selection with hands and fingers quivering on flap even though no call yet for flap extension/retraction. Ditto mitts holding heading bug in anticipation of turn.
Re autothrottle clutch motors. Boeing issued a Bulletin years ago (seen on PPRuNe in Tech Log occasionally) saying more than a slight pressure on the thrust levers against autothrottle operation may cause damage to clutches and cause incorrect AT operation.
Pilots that are lazy and rarely select the flap at correct recommended airspeed mainly on extension. Usually 20 knots or more in excess of manoeuvre speed recommendations although inside max flap speed figure. Sometimes called "using flaps as speed brakes" which is not on.
Lazy calling of 80 knots airspeed check on take off roll with the call often occuring well past 80 knots. Some pilots have never thought of also checking ground speed reading during 80 knot call even though recommended in FCTM as a fall back if erroneous airspeed problem is suspected.
Pilots calling 1000 to go when chime goes off rather than reading the altimeter for 1000 ft to go. In other words reacting to a chime rather than altimeter reading.
Pilots who have no idea of immediate actions in event of tail-pipe fire after engine shut down after taxiing. They then cannot locate this in QRH and faff around while the ground melts below the burning tail pipe. Although this is not a Memory Item, commonsense dictates you should not need a checklist to tell you what to do if it happens as passengers disembarking and ground crew yell there is a tail pipe fire.
Ditto suspected tail strike during lift off.
In simulator crew who "share" items during manual reversion approach and land. "You work the throttles for me and I will work the controls" Some regard this as good CRM. In fact it can lead to uncoordinated thrust/pitch coupling. This writer has seen Boeing advice that sharing the controls was never envisaged in manual reversion because one pilot can easily operate power and fly as normal. Boeing said if two pilots were required to be on the controls for manual reversion it would be stated in the FCTM and a third crew member would always have to be carried in case of incapacitation of one pilot.
Fast taxiing and heeling around turns to make up time.
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Old 25th Oct 2011, 16:23
  #22 (permalink)  
 
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[/LIST]Sorry to nit pick, but the thread was for B737 gripes/misunderstandings. Many answers are relevant to any type. So, to prove I'm like minded and fickle I'll add mine. [/LIST]Asking ATC if there is any speed restriction below FL100, keeping the speed at >280 then pulling speed brakes at 3000'. You might save 15secs if you're lucky.[/LIST]Flying visual circuit arrivals in level flight, or even worse in VNAV/LNAV and autopilot. This has been touched on many times in other threads, so I apologise. [/LIST]Fuel cross feeding/balancing well before the IMBL caution is alive. First 1 way then the other. No time to monitor if there is a leak.[/LIST]Pumping the elevators on rotation and flare.checking loadsheets with Japanese brains. No idea of gross error checks nor mental arithmetic; even the university wallers.
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Old 25th Oct 2011, 17:16
  #23 (permalink)  
 
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gorter wrote:

So have i misinterpreted what boeing wants then? I read it that in the cruise boeing want you to maintain a thrust and take whatever speed you're given.
Boeing wants you to set a target thrust to get a target speed for cruise.

That target speed for all phases is 280 and .76 (or .73 for the classic). The AFM makes that clear. So does the PH. The FCOM takes away the emphasis on the target cruise speed and just gives you the technique.

Can you think of a reason why climbing or descending through FL340 in turbulence you should be at M.76/280 but while cruising at FL340 you should be at another speed?
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Old 25th Oct 2011, 17:31
  #24 (permalink)  
 
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I can't believe that anyone thinks that it is a good idea to reconfigure the bleeds by memory after a bleeds off departure..

Surely this life preserving measure should be done from a checklist everytime.
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Old 25th Oct 2011, 17:42
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I can't believe that anyone thinks that it is a good idea to reconfigure the bleeds by memory after a bleeds off departure..
Depends!

On the 737-200 and early 737-300 charter operation almost every take off was bleeds off so we knew the procedure so well we could do it in our sleep (we often did!). Can't ever recall one occasion where anybody got it wrong - we were very aware of what we were doing and when to do it.

With the better performance of modern a/c it's more of a rarity so you might feel better being propped up by a checklist if you feel it's a big deal.

And then there is the question of R/T - I cringe when I hear "Standing by for Descent" instead of "Request descent" or "Bloggsville Leary XXX Request" ..."Leary XXX Pass your message"....."Leary XXX we were just wondering if FL 380 was available" - why not just say "Bloggsville Leary XXX Request FL380" ?

Last edited by fireflybob; 25th Oct 2011 at 18:05.
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Old 25th Oct 2011, 18:08
  #26 (permalink)  
 
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FFB, I accept that on the 200 it may have been a routine procedure but surely now that's not the case isn't it is good practice to be 'propped up' by the checklist?
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Old 25th Oct 2011, 18:14
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FlyingRat, I think it probably depends on what you have been trained to do - the modern way is to do things procedurally rather than teaching understanding as to why you are configuring bleeds and how to do it.

Even if you use a checklist you can still get it wrong and/or forget to reconfigure.
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Old 25th Oct 2011, 19:11
  #28 (permalink)  
 
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Glad someone beat me to the "speed" call thing. Heard it too often, calling 1 knot below Vref + 5 as a speed excursion.
F/O's calling "You have control" at 59.9 Kts. Sometimes letting go of the controls. Sometimes with reverse above idle still selected.
Not knowing how to avoid the "Alt acquire trap" before G/S capture. Sometimes going around because the aircraft "Got them too high".
Failing to call rotate if the speeds drop out of the FMC.
"Why did we just fill out the bug card?"
"I thought it was a legal thing."
This latter sadly reflects too many companies arse covering ethos as is making a standard call long after it would have been relevant.
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Old 25th Oct 2011, 20:09
  #29 (permalink)  
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Find it quite amusing that this thread is entitled "Common Misunderstandings" and yet you cannot agree amongst yourselves!

Maybe it would be better to title it "Training system fails to get the correct message across?"
Maybe. Thing is though, when you start a thread you never know who is going to contribute and whether they will be constructive or contankerous The main thing is that some interesting discussion points come up, people read them, people think, less experienced pilots learn.

so you might feel better being propped up by a checklist if you feel it's a big deal.
Interesting choice of words. It leaves no doubt about how you view the abilities of someone who chooses to use the sups in that situation.

Personally I use the sups, I know the system and when I was flying out of an 1800m strip daily I used to do it by memory but now that I do it about once a year I use the sups. It might take three seconds longer, thats all, and it is not an indicator of how well you know the system at all.
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Old 26th Oct 2011, 02:06
  #30 (permalink)  
 
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isn't it is good practice to be 'propped up' by the checklist?
No. It is not good airmanship to use a checklist as a crutch to tell you what to do because you are too damn slack to know what to do. There are supposed to be two professionally qualified pilots in the cockpit. It takes a split second for one pilot to glance over to quietly check the switching is correct. You would be staggered or dismayed to see as we have in the simulator the number of pilots during recurrent training that have forgotten how to cross feed or confgure bleeds. When questioned the answers are all the same. We use a checklist so why bother knowing what to do?
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Old 26th Oct 2011, 02:14
  #31 (permalink)  
 
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Hmmm… how about when a newbie Microsoft type F/Os who refuse to look out the window on a beautiful VFR day at altitude, makes a request with ATC to circumnavigate non-existent weather being painted on the radar which is clearly below the jet… and without consulting with the guy in the left seat.

Or another favourite… “Master caution associated”. I ask associated with what… then come the deer in the head lights gaze.

Any of you ever experience the tap on the rudder peddles whilst taxiing? I cut to the chase and pull out the FCTM and FCOM to enquire where in the manual does it state that the F/O shall ride the rudder peddles. Again… deer in the head lights gaze.

Ahhhh Microsft pilots... where would we be without them??? No one to make fun of.
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Old 26th Oct 2011, 10:38
  #32 (permalink)  
 
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With reference to the cabin rate of climb. If you are unpressurised, the cabin is still going to climb. My technique is to also look at the differential pressure indication, it's also easier because it is a big dial. When clean at about 3000' the diff will be about 2 psi. At 10000' the diff is about 4 psi. To me it's like a big analogue clock. When clean I want to see ten past twelve. At 10000' I'm looking for twenty past twelve. At 20000' it's about 7 psi or twenty to two.

My other pet hate is not calling the FMA correctly. LVL CHG is the button you press on the MCP. MCP SPD is the pitch mode that is engaged. Same for VNAV. VNAV what? VNAV SPD or VNAV PTH. Announce the FMA.
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Old 26th Oct 2011, 11:13
  #33 (permalink)  
 
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Interesting choice of words. It leaves no doubt about how you view the abilities of someone who chooses to use the sups in that situation.
framer, I think you are misinterpreting what I am saying there!

Of course it's a good thing to use all the resources that are available and I would be the first to encourage reading of a supplementary procedure if necessary.

What I am saying (and I think this has been also mentioned by Tee Emm) is that there seems to be less and less in depth understanding about what you are doing and why you are doing it. If you understand same then the procedure makes a lot more sense rather than blindly following a "checklist".

I am all for this thread which has raised some interesting topics but perhaps a more productive question to ask is how we can get these messages across effectively to line pilots. Does the operator in question have an SOP manual for guidance? My last operator did and it was a very useful document.

I think what has manifest itself to a degree in this thread is that we all tend to have our own personal prejudices. A good operator will have clearly defined procedures but there is, as they say, more than one way of skinning a cat and, as some recent accidents have proved, there are dangers in discouraging pilots from having "original thought" and therefore necessary to provide a balance between structured procedures and common sense airmanship (ahem I mean "Threat and Error" management).

If you have experienced crews who know what they are doing you could maybe issue an Ops Manual which says "Don't crash the aeroplane", on the other hand if you have very inexperienced crews you have to issue an Ops Manual which spells out in minute detail exactly what is required. In reality all Ops Manuals are between these two extremes.
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Old 26th Oct 2011, 13:24
  #34 (permalink)  
 
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Why would you not allow the F/O to have his feet resting gently on the rudder peddles during taxi?
. Nothing to do with ego as you would well know. "Riding" the controls no matter how lightly is not only unnecessary but intensely distracting for whoever is the pilot handling at the time. If the reason is a perceived flight safety precaution in case the other pilots karks without telling you first, then you would know from experience it takes less than a split second to move feet from the floor where they are near the pedals to the pedals themselves. The distraction occurs when the handling pilot from the corner of his eye sees the other bloke's knees or legs moving in unison with his own leg movements. Same with Nervous Nellies who hover with hands creeping towards the control wheel near the flare just in case you know, you fall dead at the flare.

Of course different captains will give you their personal views on such matters as will different first officers. But let's be sensible for Christ's sake and act normally with the controls as one would being a passenger in the front seat of a car. Most abhor back-seat drivers in a car and for good reason. And that is distraction when the driver is concentrating. Same principle in the aeroplane. Distraction. I have observed some pilots on take off with their hairy hands grasping the thrust levers in a claw-like fashion up to V1 with their hands poised in a grotesque shape as if afflicted with polio to demonstrate their readiness to abort at the slightest indication of a problem.

You can almost hear their exhalation of breath once V1 is called and in sheer relief they can take their claw from the thrust levers. It looks so bloody contrived. And is. Some pilots will always be a bit nervous when the other chap is handling pilot. And riding the controls is a manifestation of this. So be a good lad and keep your fingers and feet clear of the controls when the other chap is flying.
Doing so won't kill you you know and makes for harmony on the flight deck.
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Old 26th Oct 2011, 19:48
  #35 (permalink)  
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What I am saying (and I think this has been also mentioned by Tee Emm) is that there seems to be less and less in depth understanding about what you are doing and why you are doing it.
I'm with you now.

I am all for this thread which has raised some interesting topics but perhaps a more productive question to ask is how we can get these messages across effectively to line pilots.
Well you're getting the message to me and I'm a line pilot. There are about twenty really good points so far and a couple that I'm going to debate when I knock off work tonight. I think the tricky bit for line pilots is that they get told different things from each trainer. You can see from this thread that there are some very passionate people, they have their own ideas about how things should be done and they don't all agree with each other. There is not much more frustrating than having it suggested you do something on one check, and then on the next check doing it, only to have it suggested to you that you don't do that. That actually happens quite a bit in my experience. Maybe each airline should have a private forum where only check and/or training Captains can log in and formulate a united front on individual issues as they come up. The feet on the rudder pedals is a good example of what needs sorting out. As an F/O I always had my feet resting lightly on them.If it turns out that the other checkies don't have an issue with it, then the united front should be that it's fine to have your feet resting on the pedals (as is written into the books in two airlines I've worked for). Rather than have fifty F/o's adjust their habits with one Captain it would be better for one Captain to adjust the way he deals with the distraction.
Just my opinion, the main point is a united front would be good from the line pilots perspective.
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Old 26th Oct 2011, 20:03
  #36 (permalink)  
 
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Reivilo asks...

Why would you not allow the F/O to have his feet resting gently on the rudder peddles during taxi? I don't see a big problem in that, other than that it might hurt the ego of the boss in the left seat?
Nothing to do with EGO Reivilo... it's all about proper cockpit etiquette

Also… Reivilo

1. It's not SOP;
2. It's not in the Boeing FCTM;
3. It resting of feet on the peddles can be construed as falsely required inputs, if the P1 is unaware of the P2s dogs on the peddles.
4. Notwithstanding above, it's about as annoying when the Microsoft Pilot commences the taxi in procedure with hands waiving aimlessly about the cockpit whilst barreling down the runway at 60 knots.
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Old 26th Oct 2011, 23:52
  #37 (permalink)  
 
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Can definitely not agree with generally retarding the throttles at 20-30 feet.
Sure, it gives you consistent "ok"-landings, but from my experience (around 1500 landings) the best landings resulted from keeping some power (maybe 45-50% for F40 on a 733) until 10-15 feet with a late break at around ten feet.
Consistently produced very gentle touchdowns right at the 1000ft-marker.

However, one should be absolutely aware of the plane's energy-status when doing such a late break, or
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Old 27th Oct 2011, 12:23
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it's fine to have your feet resting on the pedals (as is written into the books in two airlines I've worked for).
What is written in the books in the two airlines you have worked for are nothing more than the personal gimmicks of whoever in management wrote the books. The law of Primacy ensures you remember what ever technique was taught to you in your early training. And if that includes riding the rudder pedals while the other pilot is handling, then fill your boots as they say.

One of the greatest potential dangers of that particular habit (riding the pedals in case you decide personally to apply brakes on for some reason) is the take off roll. Let's assume the captain is conducting the take off. The F/O is riding all primary flight controls except the thrust levers. After all, if you think that riding the brakes is a good flight safety precaution, then to be consistent you should also ride the control wheel as well.

Nearing V1, you see a flock birds rising from the runway ahead. You tense up. But the captain says nothing and instinctively or maybe inadvertently, you apply partial brake pressure in anticipation of the coming abort. But the captain has already decided to continue because he isn't worried about the birds. Your nervous tick in applying slight brake pressure then automatically dis-engages RTO. Now if a real abort takes place there is no RTO just when you need it most. The law of unintended consequences?
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Old 29th Oct 2011, 10:29
  #39 (permalink)  
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Why would you not allow the F/O to have his feet resting gently on the rudder peddles during taxi? I don't see a big problem in that, other than that it might hurt the ego of the boss in the left seat?
I ask because I've had a few training captains advising me to actually do this, one of them with the story that he once as a F/O had to hit the brakes because they would otherwise have caused a runway incursion. (Heavily delayed flight, in a hurry to make the slot...)
Where I come from, we operate the controls one pilot at a time, I don't require any assistance from an FO, some people call them the MS crews, I call them the SOP squad, who love to quote the SOP when convenient, and disregard it when not convenient.

Other items mentioned by fireflybob:
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Old 29th Oct 2011, 11:37
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I can't believe that anyone thinks that it is a good idea to reconfigure the bleeds by memory after a bleeds off departure..

Surely this life preserving measure should be done from a checklist everytime.
That's why packs & bleeds are in the after T/O checklist .

some things I noticed:
- flying in V/S when inappropriate (MCP speed much lower than actual speed / when ATC asks for a minimum rate of climb and VNAV is unable)

- people thinking they only have 12 minutes to reach 10 000 feet in an emergency descent

- CL: people pushing TO/GA before engine are spooled up & around the same value.

- general: people thinking "we have him on TCAS" is relevant.
- it does not help you, TCAS is not reliable in the lateral sense
- it does not help ATC.

- People not completely understanding FMC non-precision approach. depending on database. Some databases only show points on the approach related to safety altitudes. When the safety altitude change is for example 2 miles before the actual descent point with a 3 degree glide there is no waypoint where the descent starts. Pilots then think the FMC is wrong.

- pilots not crosschecking VNAV path with distance to go.

There are some more but I can't think any at the moment.
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