Ask The Pilot

[legroom]

Thanks, JB

Interesting that you need to carry a licence as well. One would have thought everyone would either know you by sight or the ID card should be sufficient.

When would you have to produce them ? Who has authority to request them ?

I'm not aware there is any RBT up there.

That will vary with airlines and aircraft. It wasn't that long ago that Australian domestic pilots were carrying personal copies of the Jeppesen charts, at about a million kgs each. Now, all I need, is an ID card, passport, licence, and iPad.

 

[jb747]

Interesting that you need to carry a licence as well. One would have thought everyone would either know you by sight or the ID card should be sufficient.

When would you have to produce them ? Who has authority to request them ?

I'm not aware there is any RBT up there.

My ID card will be looked at multiple times on the way to the aircraft. Last look is often about a metre from the a/c door. Licences will be looked at any time there is a check airman on board, even if the check is for another member of the crew. Any of the local CASA equivalents can decide to look at them ( and the aircraft paperwork ) too.

RBT? Well, you don't have to pull over for it, but both drug and alcohol testing can happen at the start or end of any flight, anywhere.

 

[mjt57]

There are basically two different plumbing systems, one of which is used for normal transfers, and the other for trim transfers...but in certain circumstances, it will start an alternate transfer, and use the other plumbing. There are two pumps per tank, but only one is on at any given time...the other is a backup, and transfer to using the backup also happens automatically. All you need to do is turn off the failed pump.

Can you select either pump for duty? And do you do routine tests on the standby pumps (to ensure their reliability, etc.)?

A double pump failure from a feed tank is treated a bit differently. Fuel will gravity feed from these tanks, but obviously the engines prefer their fuel to be delivered under pressure. So, initially we'll open all the cross feeds

Opening the x-feeds is obviously a manual operator function. How does the software handle that if it's all on auto?

In general when you get an indication of a fuel pump problem it's actually false.

Finally, does the software report actual feedback from a pump to indicate whether it's running, stopped or in fault? Or does it rely on purely logic and supposed status to indicate its, well, supposed status?

What I'm trying to say is that for example, in a process plant (whatever it may ) a PLC will tell you that a pump or valve is running or open but it may not necessarily be the case. In other words, it's just telling you what it's supposed to be doing. Other systems use limit switches, contactors and so on to provide an actual feedback to indicate an item's actual status.

Just wondering how Airbus, Boeing and so on do this sort of thing.

fuel pumps are something that we all have a healthy fear of...you don't cycle anything that is immersed in fuel. The software seems to have been written with those issues in mind.

You'd hope that the pumps would be designed with this in mind. ie. intrinsically safe. Aeronautical engineering standards are many levels above what I'm used to dealing with. But if you guys have a "healthy fear" of something, I suppose that it's better to be safe than sorry at FL380...

 

[YSSY]

Re: IFE - Moving Map Data

The position of the aircraft for navigation purposes is fed by a combination of GPS (now called GNSS) and INS (Inertial Navigation Systems). The combination of two or more INS with GPS provides a blended solution that feeds the Flight Management System and the nav displays. It is normally automatic as far as the pilot is concerned.

Many thanks for your reply. I am more trying to understand where the route data and speed comes from, because the data shown on the IFE seems to change and I wondered whether it had data on the approach and planned speed reductions or if it was a very basic A-B distance based on current ground speed, which of course would be inaccurate. I am just surprised at how accurate the timings seem to be, often from the middle of a long haul flight they can be accurate to the minute...

 

[Quickstatus]

JB:
What strategies do pilots use to maintain vigilance, minimise inattention while they monitor the screens and aircraft in front of them on long haul flights during cruise.

 

[Captain Halliday]

Hi JB, many thanks for your insight into a world many of us will never experience. (Flight Sim on your PC doesn't count people - you know who you are!)

Can you discuss the factors that influence your angle of attack on TO. Specifically the degree (if any) to which the pilot has control. Given all the factors - aircraft performance, terrain/buildings, ATC requirements for you to be at a certain level by X waypoint, company requirements etc, is there any pilot influence? Any instances where you might opt for a shallow angle of attack where terrain (or lack of it) allows such as 16L/16R in SYD?

 

[jb747]

Re: IFE - Moving Map Data

Many thanks for your reply. I am more trying to understand where the route data and speed comes from, because the data shown on the IFE seems to change and I wondered whether it had data on the approach and planned speed reductions or if it was a very basic A-B distance based on current ground speed, which of course would be inaccurate. I am just surprised at how accurate the timings seem to be, often from the middle of a long haul flight they can be accurate to the minute...

See post 6616...

 

[jb747]

JB:
What strategies do pilots use to maintain vigilance, minimise inattention while they monitor the screens and aircraft in front of them on long haul flights during cruise.

I find that the other guy's snoring tends to keep me awake.

It's a problem. On flights over busy airspace there's normally plenty going on to keep you awake, but on long over water flights there is very little activity. We carry extra pilots and so can normally take a break every few hours, but if you really hit a wall, then it's best to make use of some 'controlled rest' and, having made sure the other pilots knows what you are doing, to shut your eyes for 15-20 minutes. It can make a lot of difference.

 

[jb747]

Can you select either pump for duty? And do you do routine tests on the standby pumps (to ensure their reliability, etc.)?

No...we can only force a pump change by turning the main off.

Opening the x-feeds is obviously a manual operator function. How does the software handle that if it's all on auto?

It doesn't. The cross feeds allow us to force an engine to be fed by other feed tanks. Normally it would only be used after some system failures, or if manually balancing the fuel. It isn't a function that the automatic system should need.

Finally, does the software report actual feedback from a pump to indicate whether it's running, stopped or in fault? Or does it rely on purely logic and supposed status to indicate its, well, supposed status?

The system knows what is actually happening...and if there's a difference between commanded, and actual, then that's an indication of some form of problem.

What I'm trying to say is that for example, in a process plant (whatever it may ) a PLC will tell you that a pump or valve is running or open but it may not necessarily be the case. In other words, it's just telling you what it's supposed to be doing. Other systems use limit switches, contactors and so on to provide an actual feedback to indicate an item's actual status.

I know what you mean. The 747 fuel synoptic used to display what should be happening based upon switch position, valve position, and system status. It didn't actually use flow measurements....but that is just for a display, and not needed to operate the system.

You'd hope that the pumps would be designed with this in mind. ie. intrinsically safe. Aeronautical engineering standards are many levels above what I'm used to dealing with. But if you guys have a "healthy fear" of something, I suppose that it's better to be safe than sorry at FL380...

I'm sure they are..but we still don't play with immersed pumps. If we need to cycle it, then there is something wrong already...and I've never yet seen something designed by an engineer that is incapable of going wrong.

 

[jb747]

Hi JB, many thanks for your insight into a world many of us will never experience. (Flight Sim on your PC doesn't count people - you know who you are!)

Can you discuss the factors that influence your angle of attack on TO. Specifically the degree (if any) to which the pilot has control. Given all the factors - aircraft performance, terrain/buildings, ATC requirements for you to be at a certain level by X waypoint, company requirements etc, is there any pilot influence? Any instances where you might opt for a shallow angle of attack where terrain (or lack of it) allows such as 16L/16R in SYD?

What do you mean by angle of attack? At a given G loading, it's a fixed number for any given combination of IAS and weight.

Or are you perhaps talking about pitch attitude? Quite different things.

 

[ChrisGibbs]

JB747 - slightly OT. An ex RAN Captain is doing some research into members of the Fleet Air Arm who received awards for services to the RAN - aka Project Bravo Zulu. I'm pulling together my father's Record or Service and other relevant material to respond. In doing some digging around the various Fleet Air Arm Association website/s I came across the following: ran-faa-a4g-ofs | A-4 Skyhawk Association. I'm sure you've seen this before but some interesting names around yours come up including a young midshipman who is current CDF.

 

[YSSY]

Re: IFE - Moving Map Data

See post 6616...

Thanks, not sure how I missed that.

 

[Quickstatus]

I find that the other guy's snoring tends to keep me awake.

It's a problem. On flights over busy airspace there's normally plenty going on to keep you awake, but on long over water flights there is very little activity. We carry extra pilots and so can normally take a break every few hours, but if you really hit a wall, then it's best to make use of some 'controlled rest' and, having made sure the other pilots knows what you are doing, to shut your eyes for 15-20 minutes. It can make a lot of difference.

When you scan the monitors /screen in front of you on those long over water sections, what do you do to make sure that whatever you see on monitor is acknowledged at some level and you don't miss anything.

 

[knasty]

On the point of staying alert I have recently flown QF5/6 on 747 and A330. In both directions the 747 was 2 man crew and A330 was 3 (ie. + SO). Is this because the 747 has higher cruise speed hence shorter expected flight time or would the A330 often run a 2 man in this as well?

 

[Captain Halliday]

What do you mean by angle of attack? At a given G loading, it's a fixed number for any given combination of IAS and weight.

Or are you perhaps talking about pitch attitude? Quite different things.

See, I don't have a clue. Yes, I mean pitch. In plain English, are there circumstances when you might not gain altitude quickly but instead climb slowly.

In part this questions comes from reading something about Brisbane City Council allowing taller buildings and as a result departures on 19 in BNE would take a steeper clib (or may already be doing so). So I wondered whether there was any pilot discretion where this didn't aplly - such as over water departures.

 

[jb747]

When you scan the monitors /screen in front of you on those long over water sections, what do you do to make sure that whatever you see on monitor is acknowledged at some level and you don't miss anything.

You look at different displays in somewhat different ways. The PFD (primary flight display) is right in front of us, and it displays all that you need to actually fly the aircraft. In the cruise it's fairly static, but any changes stand out. Mode changes are outlined by the aircraft for a few seconds. On the nav display, about the only things that change in the cruise are the weather and other aircraft TCAS paints, so they stand out by being different.

Systems displays are always showing multiple systems, i.e. all of the engines, or both hydraulic systems. There it's the differences between the individual systems that grab attention. But, remember, the aircraft is also monitoring all of the systems, and it will use colour and warnings to bring things to your attention. A colour change is very attention grabbing. Pop ups are also used...a system is not displayed at all until something noteworthy happens.

We generally don't respond to the system synoptics. Whilst it's interesting to watch an hydraulic system slowly lose its fluid, action is not normally taken until it trips the ECAM/EICAS warning systems.

 

[mikenz]

the only things that change in the cruise are the weather and other aircraft TCAS paints, so they stand out by being different.

Hypothetically, would your systems have any view of a plane that had all its identifiers switched off/not operating? I'm obvioulsy thinking back to the MH disappearance. Would any nearby aircraft have been able to see it?
Appreciate there is another thread on MH, but interested in the Pilots' view.

Thanks

 

[jb747]

See, I don't have a clue. Yes, I mean pitch. In plain English, are there circumstances when you might not gain altitude quickly but instead climb slowly.

In part this questions comes from reading something about Brisbane City Council allowing taller buildings and as a result departures on 19 in BNE would take a steeper clib (or may already be doing so). So I wondered whether there was any pilot discretion where this didn't aplly - such as over water departures.

On take off, we recalculate an engine derate. Derating the engines means that we don't use full power, but up to around 35% less, which makes the engines last longer, and also increases their long term reliability. This calculation will also take into account any obstacles.

Having worked out your power, the pitch attitude is simply what you end up with to control the speed. (We don't accelerate after take off until we reach the 'clean up' altitude, when we accelerate and retract the slats/flaps.) In the A380, at all normal weights, it's about 12½º. Domestic 767s, which are quite light, and also very powerful, can end up with pitch attitudes as high as 30º. The angle of attack, is the angle between the actual airflow and where the aircraft is pointed, and just after lift of is probably somewhere around 6º. Subtract that from the pitch attitude, and you'll get the angle that the aircraft is actually climbing away from the ground. So, 767 climbs away steeply, and 380 doesn't.

As the aircraft gets heavier, the derate will disappear, and that really steep 767 climb out will lose about 12º.

But, we live in a world in which we plan on things going wrong. So, lets add an engine failure to the mix. In the A380, we've just lost 25% of the total thrust. If any derate was being applied, we can remove that, but we're often in the case where there is no extra power. Then the climb angle becomes very shallow, and whilst it's still planned to miss obstacles...that margin can be very small. And in any of the twins, the effect of the loss of an engine is obviously much more dramatic...but it still has to miss those planned obstacles.

Putting obstacles in the way, will have a number of effects. It will reduce the amount of derate that can be used, and so shorten engine life. It will increase the height at which clean up is carried out, which has the effect if increasing the noise footprint. Ultimately it reduces the maximum weight that a long haul aircraft can carry...and so reduces the operational options from an airfield. It could even make some otherwise viable long haul operations uneconomic.

 

[jb747]

Hypothetically, would your systems have any view of a plane that had all its identifiers switched off/not operating? I'm obvioulsy thinking back to the MH disappearance. Would any nearby aircraft have been able to see it?
Appreciate there is another thread on MH, but interested in the Pilots' view.

No lights, no TCAS. Middle of a dark night. Basically there's nothing to see, so unless there was a bit of moon you'd be very unlikely to see anything. Contrails can stand out at night if illuminated by the moon. The radar would see an aircraft, but it wouldn't be all that noticeable, and you'd be very unlikely to pick it out. It would just be a small transient return, of which there are hundreds on any given flight. You normally only notice aircraft radar returns because they're on the same track, and have a TCAS marker superimposed upon them. Plus you'd need to be within about 30-40 miles.

 

[jb747]

On the point of staying alert I have recently flown QF5/6 on 747 and A330. In both directions the 747 was 2 man crew and A330 was 3 (ie. + SO). Is this because the 747 has higher cruise speed hence shorter expected flight time or would the A330 often run a 2 man in this as well?

The 747 is a bit faster than the 330, but that's probably not the reason for the crew structure. The 767 was about the same speed as the 330, and it operated most of the Australia to Asia sectors with a two man crew. Lots of things can affect the crewing of the aircraft. For instance, we mostly operate the 380 between Dubai and London with a two man crew, but an SO might be added if the weather makes a diversion likely. A pattern can include many sectors, and could hit limits like the 7 day 2 man crew hours limit. That particular limit often arises for the 380 DXB-LHR sectors too.

So, looking at a sector in isolation, it may well be possible to do it with a two man crew. But, when you look at the overall pattern construction, and even the work done by individual pilots, the crew structure can change.