Some questions about commercial flying

[Nicholas49]

Hello

I wonder if I can ask the following questions? They are completely unrelated, but I thought it made more sense to group them under one thread rather than opening lots. Here goes:

1. I know that airlines have a way of recording flight data to monitor whether pilots are adhering to SOPs. What is this called? Is it different technology from the black box? Does it store as much data as the black box or is it more limited in what it records?

2. I was listening to Geneva tower earlier via the Internet and I heard what I would describe as a heated discussion between the tower controller and a pilot. I couldn't hear what the pilot was saying because there was so much background noise, but the controller was saying something along the lines: 'it was within our minima / you have 2,000 feet from the runway / this is the problem of having one runway at Geneva’. Anyway, my question is not about this particular incident but more general: if you get into this type of lengthy discussion with an ATCO, is there not a risk that by blocking the frequency you will irritate and potentially cause issues for other pilots? If you need to continue the conversation, how do you do it? After landing?

3. I have noticed that the noise on take-off on a B737 is louder in the cabin than on an A320. But I know that aircraft engines are not made by the aircraft manufacturers. So are Airbus aircraft better insulated? Is it down to the engine or the aircraft?

4. What is in the large roof panel on a B737-800 half-way down the cabin above the middle emergency exits?

5. Would it be possible (accidentally or deliberately) to feed your conversations with ATC through the cabin PA system or is this not technically possible?

6. Is everything you say on the flight deck recorded or is it only when pilots transmit to ATC? If you are recorded, how do you ensure that what you say on the flight deck (I imagine you discuss airline policies and have in-my last-airline chats in the cruise!) are not used improperly?

7. Landing at London Gatwick on Monday morning in what felt like reasonably gusty conditions, I noticed that on touch-down the weight of the aircraft seemed to lurch / shift somewhat (if that makes sense). Is this in any way indicative of a cross-wind and could the pilot have been ‘straightening’ the aircraft on touch-down?

At the risk of sounding obsequious, can I say thank you in advance for taking the trouble to answer these questions. I really do appreciate it.

[Northbeach]

1. I know that airlines have a way of recording flight data to monitor whether pilots are adhering to SOPs. What is this called? Is it different technology from the black box? Does it store as much data as the black box or is it more limited in what it records?

FOQUA: Flight operations quality assurance. This device records aircraft performance that can then be compared with recommended procedures (similar to the black box). At our airline the data is not used to discipline pilots, and access to the data is controlled. The pilots union also has a mechanism where pilots can take their concerns to if necessary.

2. I was listening to Geneva tower earlier via the Internet and I heard what I would describe as a heated discussion between the tower controller and a pilot. I couldn't hear what the pilot was saying because there was so much background noise, but the controller was saying something along the lines: 'it was within our minima / you have 2,000 feet from the runway / this is the problem of having one runway at Geneva’. Anyway, my question is not about this particular incident but more general: if you get into this type of lengthy discussion with an ATCO, is there not a risk that by blocking the frequency you will irritate and potentially cause issues for other pilots? If you need to continue the conversation, how do you do it? After landing?

Yes there is a risk of blocking the frequency. If we need to continue the conversation often the tower will give the pilot a phone number to call after landing. Usually that means the tower is going to talk to you about something they feel you did wrong. It can go further, the ATC facility (FAA) can notify the FAA (different dept) and they can begin to start an "enforcement action" against you which may relult in a suspension, revocation. Your employer may get involved and suspend you without pay or terminate you.

4. What is in the large roof panel on a B737-800 half-way down the cabin above the middle emergency exits?

I suspect the place for the life raft to be stowed of overwater opeations. We have 3 on our ETOPS 737-800s.

5. Would it be possible (accidentally or deliberately) to feed your conversations with ATC through the cabin PA system or is this not technically possible?

It is possible for me to make a mistake and reply on the PA when I really wanted to reply to the controller. In that case you would hear my half of the conversation with ATC. However for you to hear ATC over the PA speak to me I would have to manipulate the radios in a very unusual way-it would be intentional.

6. Is everything you say on the flight deck recorded or is it only when pilots transmit to ATC? If you are recorded, how do you ensure that what you say on the flight deck (I imagine you discuss airline policies and have in-my last-airline chats in the cruise!) are not used improperly?

The cockpit voice recorder usually records all sounds on the flight deck; including conversations. The recording has a finite loop, only 30-45 minutes. So yes, you can guess everything said in the last 30-45 minutes could be heard by someone else with access to the CVR (Cockpit Voice Recorder. In the "West" we usually have some form of protection, however that may not be the case in other parts of the world.

7. Landing at London Gatwick on Monday morning in what felt like reasonably gusty conditions, I noticed that on touch-down the weight of the aircraft seemed to lurch / shift somewhat (if that makes sense). Is this in any way indicative of a cross-wind and could the pilot have been ‘straightening’ the aircraft on touch-down?

Yes probably a "side load" on the main gear, the jet was not completely straightened out upon landing - some manufactures actually recommend this technique under certain wind conditions.

I don't know about the Airbus vs Boeing noise issue so I skipped that one.

[Di_Vosh]

Nicholas,

Great questions, and well answered by the two posters above.

5. Would it be possible (accidentally or deliberately) to feed your conversations with ATC through the cabin PA system or is this not technically possible?

Far more common is for a pilot to make a cabin PA over the ATC frequency :} :} :}

[Avionker]

1. I know that airlines have a way of recording flight data to monitor whether pilots are adhering to SOPs. What is this called? Is it different technology from the black box? Does it store as much data as the black box or is it more limited in what it records?

I think you are referring to the QAR, the Quick Access Recorder. On the types on which I have experience this records some of the same parameters as the FDR but not all of them. The data is downloaded regularly, weekly is I think quite common. This data is used by engineering departments to monitor aircraft health and performance. It can also be used by the airline to investigate any incidents, i.e heavy landings etc.

5. Would it be possible (accidentally or deliberately) to feed your conversations with ATC through the cabin PA system or is this not technically possible?

The only way I can think of to do this would be to feed the VHF audio through the flight deck speaker and then send this over the PA using the hand mike. A very deliberate act, not something that's going to happen accidentally I would say.

6. Is everything you say on the flight deck recorded or is it only when pilots transmit to ATC? If you are recorded, how do you ensure that what you say on the flight deck (I imagine you discuss airline policies and have in-my last-airline chats in the cruise!) are not used improperly?

There is an erase facility on the CVR. This can only be activated when the engines are not running, the aircraft is in ground mode (i.e weight on wheels switches are activated) and the parking brake is applied. This allows crews to erase the recorder at the end of an uneventful flight. The CVR will record 4 or 5 tracks normally, the captains, first officers, observers (and possibly 2nd observer depending on type) boom microphones and a cockpit area microphone.

[Nicholas49]

Gents - thanks very much for the replies - all very interesting.

If I can pick up on a couple of things:

Far more common is for a pilot to make a cabin PA over the ATC frequency

Which is what happened in the BA 038 incident, if I am not mistaken. Are there two buttons next to each other, one that says words to the effect of 'Cabin PA System' and one that says 'ATC'? Or is it more complicated than that? It also occurred to me that on a few airlines (American?) ATC transmissions are available on the IFE, so they must be fed through somehow.

Can anyone help with Q3? The difference in cabin noise on take-off between an A320 and a B737 is noticeable, IMHO. It's one of the reasons I prefer to fly on the B737 simply because the take-off feels more dramatic.

[Avionker]

Nicholas, have a look at these photos:-

Audio Control Panels (http://www.flightdecksolutions.com/forum/viewtopic.php?p=27858&sid=b2a743bbd44a3e1ee9cc62412cacdae0)

These are replicas but are actually quite convincing. Each of the knobs with the arrows on top are volume controls for each comms radio, interphone, Cabin PA, Nav radios etc. You can have as many of these turned up as you wish, so it is possible to monitor several sources simultaneously.

The black rectangles are mic select switches. It is only possible to select one at a time. When you operate the PTT (Push to Transmit) switch whatever you say is routed to whichever system has been selected on the Audio Control Panel. What can happen is that the pilot may have made a cabin PA and later when they need to talk to ATC he (or she) toggles the PTT, talks away, and forgets to check the mic select switch.

As for noise levels in 737's ans the A320 family, well it must be something to do with design I'd say, but what exactly I don't know.