Boeing cockpit ''grammar''

[ASCTU744]

On the 747-400 (and other Boeing aircraft) we see cockpit labels that sometimes don't make sense.

I think the best example is the Equipmet cooling selector.

On the 747 classic you had the same modes, with intuitive labels:
SMOKE (Using differential pressure to blow smoke out of the plane)
NORM (NORM)
DITCH (Closing the overboard valves to prevent water from entering the E/E bay during ditching)


Why did Boeing change that to STBY, NORM and OVRD?

-Nadir

[boeing747430]

I don't recall the exact configuration and behaviour of the 747 classic equipment cooling and am too lazy to search for my old AOMs. Still, it may very well be that in the 747 classic's abnormal procedure for ditching, this switch position was being used.
Alas, on the 744/748, the NNC for ditching doesn't even mention any action on the equipment cooling. When it comes to sealing off potential holes, the only thing you do is closing the outflow valves. I'd recon' that the effect of the ground exhaust valve on the overall flooding is negligible.

Since you'd be using the OVRD position of the switch in more cases than just smoke scenarios, it makes sense to name it this way. STBY puts the system in standby for flight if the air/gnd switching fails for the system. So it makes sense as well.

But what about "nacelle anti ice" and "engine anti ice"?
Discuss!😉😅

[ASCTU744]

Thank you! So the labels are more made from an operation standpoint rather then a "knowledge" standpoint?

On this site you can see the panel differences between 737 generations.

http://www.b737.org.uk/aircraftsystems.htm





I suppose that lights/labels are also changed too cover a wider range of malfunctions/functions (Like what you said about the OVRD mode)? Rather then simplification only (MAINT means more then low oil quantity and Fault more then high oil temp?)

But what about "nacelle anti ice" and "engine anti ice"?
Discuss!😉😅

🤣, I think it makes sense. Because you're only heating the nacelle of the engine. But I prefer engine anti ice as it's straightforward.

[boeing747430]

Ok, your last pics do indeed show very different systems on the same aircraft model. The first two pics show on top the panel for the older CSD (constant speed drive) generators on the 737, while the other pic is for VSCF (variable speed constant frequency drive) generator. On the CSD you need the gauges to show you oil temperature and rise between oil intake and outlet. Both are a measure of health. The VSCF is more modern and self contained. So the "drive" light basically just tells you, that there is something wrong (or the engine is off), but not exactly what it is. You don't need to know anyway - it's broken, or not.

The other two pics show two generations of APUs, and there would be at least three different ones on the 737-3/-4/-5 that I flew back in the day. I only know the upper version and then we had a newer APU where there was a blue "APU" light instead of "low oil quantity", which would cover a few more faults.

I am quite certain that, if it weren't for the common type rating with the 744, the 748 "labels" of systems would have been very different indeed.

I flew a few months for a different airline on 737-3/-4s on lease from my company. There were quite a few discrete cockpit layouts on those, because some led a different life before coming to that company. They had different specs and some were quite confusing to me in the beginning. Some aircraft even had switches in the cockpit where there was no description to be found in the books. So the knowledge was transferred by hearsay.     But don't worry - no essential switches. Until that time, I wasn't aware that you were allowed to fly such a wide range of cockpit layouts with one type rating. Later came the A320-family, and one of my colleagues counted at least 14 different cockpit layouts in our company. A319/320/321s in up to four generations.

All of the five C172s in my local flying club, for example, have very different panel layouts and some differences in instrumentation.

A friend of mine is in transition to A330/350. He did all of his training in 330 only and is fully checked out now, but so far, he has not seen the inside of an A350. Technically, he would be fully qualified to fly the 350 - and now compare the 330 cockpit with the 350 one.
No worries - he will get 5 missions on the 350 simulator, before he will be able to fly you. But it is not strictly required by the authorities.

In the end, most pilots I know don't care too much. You would be surprised to find, that very few are real nerds or geeks, at least in the big legacy carriers, where you get sponsored training. Here, you will find a lot of pilots, who as a child or adolescent never wasted a thought on becoming a pilot and who went this way by sheer coincidence. This, of course, would be very different in companies without sponsored initial pilot training.

Me - I don't care too much as well, as long as I don't have too many panel differences. I am quite happy to be back on the 744/748 where the only difference on the discrete models to me would be the possibility to use a tail tank or the possibility that it is not even equipped. So, if you will, only two cockpit layouts (744/748) with minor differences between them, and two switches which could be there, or not, and usable, or not. Such a relief coming from 320s.

[Jeroen Hoppenbrouwers]

You don't need to know anyway - it's broken, or not.

From my side of the industry I can confirm this, with an engineer's twist.
Yes, from the airplane installation perspective you need just one light: BROKEN.
This is typically what the certification is about. And it's perfectly ok for pilots.

However then the pilot calls the maintenance tech or writes up a log entry, and the poor people now facing the issue see BROKEN and switch the thing off and on and fumble a bit and shrug. Next thing they start throwing parts at the airplane until the light goes away, and often the replaced parts were not even the reason why the light was on.

Enter the Central Maintenance Computer that attempts to diagnose exactly what went South and suggests either a direct repair (replace) action or some further fault isolation. All great, if all equipment was in the design when the CMC was programmed. Not easy when you add something later.

So I am constantly trying to a) keep the pilots and installation/certification people happy with simple if not simplistic indications IT WORKS/IT DOES NOT WORK, and b) then the line techs with very quick fault isolation procedures using for example CDU pages with summaries, and c) the installation techs with more extensive what-if instructions to figure out which two wires they have mistakenly swapped. Very hard to keep all these people happy...


Hoppie

[John H Watson]

When it comes to sealing off potential holes, the only thing you do is closing the outflow valves.

Would a crew really have time to do this after ditching... and if before ditching, wouldn't the outflow valves be fully open to ensure there was no differential pressure to prevent you from opening the doors?

[boeing747430]

The ditching non-normal-checklist calls for below 5000' switching the pack control selectors off and then closing the outflow valves. There should be very little, if any differential pressure left upon impact.

[IefCooreman]

This is just an evolution in cockpit and procedure design. Initially the switch had an operational purpose, however in modern philosophy the flightdeck the "operational" aspect is covered in SOP's and QRH. The flightdeck is simply a user interface with buttons and switches used in many different operational procedures.

Yes, from the airplane installation perspective you need just one light: BROKEN.

I understand what you are trying to say :-;... so here comes the "but" :-)

Lights are more designed to indicate a "state" that is "not normal" (when talking about amber lights). In training I like to explain "the system does not work _the way it was certified_". Ie pack overheats. Very important to keep it in mind when all of a sudden the other pack (2 pack aircraft) starts to really fail, an overheating pack is still available after cooling. As said, it is a user interface to give the pilots just the info they need in a clear cut manner, but nothing more than that.

Biggest example is engine fire. It is a state of the engine. The checklists procedures are very clear with memory items that lead to an engine shut down. However, the memory items are not supposed to be started as long as the gear is not up. So as long as _the gear is not up_, the pilot is NOT supposed to shut down the engine as in the case of engine fires, the engine is still actually very active and providing thrust. Concorde crash: the aircaft flew with the fire, it crashed because they shut down the engine with gear blocked down.

[ASCTU744]

Thank you all!

Ok, your last pics do indeed show very different systems on the same aircraft model. The first two pics show on top the panel for the older CSD (constant speed drive) generators on the 737, while the other pic is for VSCF (variable speed constant frequency drive) generator. On the CSD you need the gauges to show you oil temperature and rise between oil intake and outlet. Both are a measure of health. The VSCF is more modern and self contained. So the "drive" light basically just tells you, that there is something wrong (or the engine is off), but not exactly what it is. You don't need to know anyway - it's broken, or not.

The other two pics show two generations of APUs, and there would be at least three different ones on the 737-3/-4/-5 that I flew back in the day. I only know the upper version and then we had a newer APU where there was a blue "APU" light instead of "low oil quantity", which would cover a few more faults.

I am quite certain that, if it weren't for the common type rating with the 744, the 748 "labels" of systems would have been very different indeed.

I flew a few months for a different airline on 737-3/-4s on lease from my company. There were quite a few discrete cockpit layouts on those, because some led a different life before coming to that company. They had different specs and some were quite confusing to me in the beginning. Some aircraft even had switches in the cockpit where there was no description to be found in the books. So the knowledge was transferred by hearsay.    But don't worry - no essential switches. Until that time, I wasn't aware that you were allowed to fly such a wide range of cockpit layouts with one type rating. Later came the A320-family, and one of my colleagues counted at least 14 different cockpit layouts in our company. A319/320/321s in up to four generations.

All of the five C172s in my local flying club, for example, have very different panel layouts and some differences in instrumentation.

A friend of mine is in transition to A330/350. He did all of his training in 330 only and is fully checked out now, but so far, he has not seen the inside of an A350. Technically, he would be fully qualified to fly the 350 - and now compare the 330 cockpit with the 350 one.
No worries - he will get 5 missions on the 350 simulator, before he will be able to fly you. But it is not strictly required by the authorities.

In the end, most pilots I know don't care too much. You would be surprised to find, that very few are real nerds or geeks, at least in the big legacy carriers, where you get sponsored training. Here, you will find a lot of pilots, who as a child or adolescent never wasted a thought on becoming a pilot and who went this way by sheer coincidence. This, of course, would be very different in companies without sponsored initial pilot training.

Me - I don't care too much as well, as long as I don't have too many panel differences. I am quite happy to be back on the 744/748 where the only difference on the discrete models to me would be the possibility to use a tail tank or the possibility that it is not even equipped. So, if you will, only two cockpit layouts (744/748) with minor differences between them, and two switches which could be there, or not, and usable, or not. Such a relief coming from 320s.

The FCOM's of a lot of Boeing planes make the planes look similiar (744, 748, 777...), but as soon as you open the AMM 😅.......

Are the Airbus ECAM messages (or the information systems as a whole) more detailed then the Boeing one's?

This is just an evolution in cockpit and procedure design. Initially the switch had an operational purpose, however in modern philosophy the flightdeck the "operational" aspect is covered in SOP's and QRH. The flightdeck is simply a user interface with buttons and switches used in many different operational procedures.

I understand what you are trying to say :-;... so here comes the "but" :-)

Lights are more designed to indicate a "state" that is "not normal" (when talking about amber lights). In training I like to explain "the system does not work _the way it was certified_". Ie pack overheats. Very important to keep it in mind when all of a sudden the other pack (2 pack aircraft) starts to really fail, an overheating pack is still available after cooling. As said, it is a user interface to give the pilots just the info they need in a clear cut manner, but nothing more than that.

Biggest example is engine fire. It is a state of the engine. The checklists procedures are very clear with memory items that lead to an engine shut down. However, the memory items are not supposed to be started as long as the gear is not up. So as long as _the gear is not up_, the pilot is NOT supposed to shut down the engine as in the case of engine fires, the engine is still actually very active and providing thrust. Concorde crash: the aircaft flew with the fire, it crashed because they shut down the engine with gear blocked down.

That's a fair point, but how do pilots react on the ">" messages (especially during i.e. a checkride)? Is the QRH still used (or even allowed during checkrides) when the message is ambigious (like >ANTI-ICE)?

I know this isn't the right forum for this type of plane, but the F-16 gives the best example of "need-to-know-only" lights.

The overheat light for example illuminates for one of the following conditions: Engine, Main gear wheel well or EPU overheat.
Some lights aren't even used (EEC for example) , or don't really make sense when you have a different engine type (I think this proves @Jeroen Hoppenbouwers point on keeping both maintenance and the pilots happy)

But it's a complex single seat operated combat plane after all.

[boeing747430]

Careted messages are being called out, but the QRH is not used for them. EICAS and ECAM procedures are not that different. Still, in both you will see evolution for different generations. Strictly speaking, 744 has no EICAS "procedures" and 787 ECLs are much more sophisticated than 748 ECLs. So are A350 ECAM "actions" as compared to the A320 ones, of course.

BTW: there is no difference between check-ride and non-check-ride. One would behave in exactly the same manner.

[ASCTU744]

Careted messages are being called out, but the QRH is not used for them.

But are you allowed to look them up (if vague) during a checkride.

Please ignore this post, I sent it before your update.

[ASCTU744]

Careted messages are being called out, but the QRH is not used for them. EICAS and ECAM procedures are not that different. Still, in both you will see evolution for different generations. Strictly speaking, 744 has no EICAS "procedures" and 787 ECLs are much more sophisticated than 748 ECLs. So are A350 ECAM "actions" as compared to the A320 ones, of course.

BTW: there is no difference between check-ride and non-check-ride. One would behave in exactly the same manner.

Thank you. But I can imagine that instructors don't want you to look carreted messages up, because they should be memorized (I suppose...?).

[boeing747430]

That's the point. There is nothing special to memorise with careted messages.
We do have one single exception, which requires a procedure, though. That's the only thing I'll have to memorise about them.
And again, there is no difference between check-ride and non-check-ride. If you like, you can look at the QRH, but it will give you no further information. Before the 748, the QRH didn't even contain the careted messages.

[ASCTU744]

But I mean more like ambiguity. If I got the >ANTI-ICE message I wouldn't really know if it means: "system malfunction, no action required." Or "Anti-ice on but not needed, no action required". 😅

Oh I'm sorry I replied too fast, thank you 

[boeing747430]

A fault detected in the anti ice system would cause a non careted EICAS caution, to which a non normal checklist is then read.
Boeing says that a careted alert message is informational or requires no procedural steps.

[ASCTU744]

We do have one single exception, which requires a procedure, though. That's the only thing I'll have to memorise about them.

I'm curious now , which message and what procedure?

[boeing747430]

>BROADBAND SMOKE

[boeing747430]

I just remembered, that it doesn't exist anymore. It was reprogrammed to >SMOKE BBAND UPR and >SMOKE BBAND LWR. Still, both would trigger the same NNC.