The great big "ask an airline pilot" thread!

Jimmy444 wrote: »

I don't think this is right. Maybe things have changed but I have definitely been on aircraft while refuelling was happening. I know this because we were asked to undo our seatbelts for the duration (in case a quick exit is needed?:eek:)

Yes I remember a couple years ago being held back at the gate with my not so mobile granny while everyone else boarded. They were refuelling and knew she wouldn't be able to pull off a quick evacuation.

basill wrote: »

As the aircraft travels on its journey it traverses country boundaries as well as ATC ones. There can often be local agreements between neighbouring countries for the "sharing" of airspace and ATC services. For example London does quite a bit of the high level controlling over the eastern part of Ireland even though the aircraft may be physically still flying within the boundaries of the State.

Each controller will hand you off prior to leaving their sector and give you a VHF frequency which we then tune and check in eg:

Dublin lower ATC: Shamrock 152 contact London on 123.45
Shamrock 152: 123.45 Shamrock 152
Shamrock 152: London Shamrock 152 FL310 direct Liffey
London ATC: Shamrock 152 radar identified cleared direct Bovingdon

And on it goes......

Wow that's so interesting! Thanks so much

keith16 wrote: »

You may also be interested to know that you can listen in on ATC over the magic of the interwebz

The feed for Dublin is provided by one of our very own A&A boardsies http://www.liveatc.net/search/?icao=eidw

You can also "watch" the aircraft on www.flightradar24.com

:eek: I know how I'm going to spend my weekend!
Thank you!!!

SamAK wrote: »

I don't understand this bit - In the case of a fire, the first response is to pull the main busses and restore circuits one by one until you have isolated the bad one."

How does that even work? Isolating burning wires?

To put it in simple terms. Imagine you have an extension lead plugged into a socket at home. Plugged into the extension lead are 4 appliances.
One of the appliances has a fault which is causing smoke to build up, but you don't know which one it is.

You isolate the entire circuit at the plug in the wall and the smoke stops. You have now isolated the BUS. Now each appliance can be turned off. The extension lead plugged in again and each individual appliance turned on again to find out which appliance was causing the problem.

Its the same in an aircraft. Initially there will be a memory checklist to complete. After this once you've established if it was electrical or air conditioning smoke there is another individual checklist to complete.

In the simulator (not flight sim:D) it can take quite a while to accomplish all the above while still following the creed of Aviate, Navigate and Communicate. It's surprising how often a call to atc is forgotten in all the mayhem.


It may sound like an odd procedure to carry out but some of the other equipment on the electrical bus may be needed for the Navigate and Communicate bit of the flight. Also, this isn't the first industry I've come across a similar thought process in regard electrical faults.

Once the fault is isolated you land ASAP.

The only fire suppression equipment we have on my type is within the engine cowlings. I don't know of any type with the ability to suppress a fire within the avionics. Maybe in the avionics bay on larger aircraft but again that's outside my experience.

The wiring used in aircraft is of a very high standard. Surprisingly the first indication is a noxious smell from the insulation itself breaking down rather than actual flames and smoke. Once the power supply is removed it begins to cool, eliminating the fire risk.

There are no memory actions for smoke or fire on my type. We have a checklist which firstly reminds us that diversion should be considered and also that any time the smoke or fumes becomes bad that oxygen masks should be donned, and if smoke becomes the biggest threat then to go to a smoke removal checklist that goes as far as opening a flight deck window.
Albeit while there's no memory actions, nothing stopping one from knocking off power to the galleys immediately if the cabin crew said they were getting smoke for example, and then just take it up in the checklist.

We have fire suppression in the cargo bays as well as the engines.

Our masks are combined oxygen masks and goggles and they are smoke proof as we can set the oxygen regulator to give a flow thats higher pressure than the cabin air, thus purging the mask of smoke. You'd be surprised though just how bad cockpit visibility can be in smoke situations though, instruments can be almost impossible to see. Our smoke checklists are printed in large print to help with this.

Just a quick question about MH370, I don't want to hijack this thread.

It's hard to know exactly what 'reports' are true, and what aren't, but it seems to me that an important point is the aircraft's turn to the west, and whether it was 'pre-programmed' or not. Reports seem to suggest that they know it was pre-programmed because the last ACARS signal that was received had the pre-programmed course change in it.

So my question is this: Is it possible for ACARS data sent from the aircraft to the ground to include whether a future course change has been programmed into the Flight Computer?

Thanks...

J.

Anything I've read about the ACARS system is that a flight plan can be uploaded to the FMS. It must be manually accepted.

There is no facility to download from the FMS.

ProfessorPlum wrote: »

Cabin crew are required to check the cockpit at regular intervals to check that both crew are still alive, (and more importantly, don't need more coffee:), but take a look at Helios http://en.wikipedia.org/wiki/Helios_Airways_Flight_522

Many airlines changed their procedures after that crash, so that in the event of a depressurisation, if the cabin does not get communication from the cockpit, they are required to go to the cockpit to physically check on the crew to see if they are conscious. While the masks drop down automatically in the cabin, there is no automatic system in the cockpit, so it could happen that there is a loss of pressurisation and the cockpit crew may not be aware.

Does this procedure not have an obvious flaw? The cockpit door is locked.

eatmyshorts wrote: »

Selecting a different altitude in the window is simply telling the system what altitude you want it to capture. You then have to select a way to get there.
Level Change is one of the modes that the system can then use to attain the target altitude. Engaging Level Change commands the autopilot/autothrottle to attempt to acquire the target altitude in a time frame of 2 minutes, while maintaining the selected speed in the speed window. If this is not possible, then the autothrottle will command IDLE (or HOLD) for a descent or THR REF (or THR) for a climb.
If the altitude selector knob is pushed while the active pitch mode is in VNAV, then the autopilot/autothrottle will command a VNAV SPD or VNAV PTH climb or descent using THR REF or IDLE.

That sounds like the 777 'FL CH' mode. On the 737 (Classic and NG), 'LVL CHG' is much more simple than this...no time logic whatsoever.
Level change simply commands a pitch angle to deliver the selected speed and if in a climb delivers the maximum Climb N1 or in a descent, retards the thrust levers and then puts the auto thrust into the ARM mode (ready for when it hits alt acq and needs thrust again). Because LVL CHG is quite 'crude', we use V/S when approaching the MCP selected altitude (to achieve 1000fpm when 1000ft above of below cleared altitude) to avoid TCAS TA/RAs and it also helps with passenger comfort.

The altitude selector cannot be pushed on the 737 and if in VNAV, selecting the lower cleared altitude on the MCP leaves one with two possibilities - if ATC says descend 'when ready', no further action is needed; once the calculated top of descent point arrives, descent will commence to the MCP selected altitude. Or we can press the Alt Intervent button which will commence a 1000fpm descent until the idle thrust descent profile is intercepted.

pclancy wrote: »

Yep, the one thing that we don't want to discuss here is anything security related.

I can well understand, and almost goes without saying, absolutely sensible.

However, with a touch of devils advocate, I might ask, under mod advisement, and in light of all recent news (sorry) are you more aware or concerned about your social security.
Of course I don't mean PRSI payments, I am referring to your online presence, social networking etc that could be trawled through or abused.
I would have thought there would be guidelines, either company or professional organisation issued. This may be a broad assumption considering one of the persons involved posted both his employer, aircraft class, face and location on at least one publicly accessible networking site, along with various political views and links to other family members.
I would have thought that unwise, for a multitude of reasons.

Now that may appear bordering on paranoia, but different countries have different degrees of concern and if I was a bank manager in Ireland, I wouldn't be publishing my name, address, place of work and family members etc for probably obvious sensible reasons.

pclancy wrote: »

Cheers. So the norm would be to let the autothrottle just chop power when it approaches TOD and the aircraft starts to descend, rather then a slow gentle manual retardation of thrust to reduce speed before descending?

I remember watching an old 737 Classic documentary (think it was an airline called Go Fly at the time) and the Irish captain spoke of the "Good Airmanship" of manually retarding the throttles before TOD to reduce engine wear due to the massive changes in heat in the engines.

Which method would be more gentle on the passengers? I guess you want to avoid negative G sensation when you hit TOD.

Capt John Mahon

Thought it might be as easy as pulling the breaker but maybe not?!