Proximity Warning Over Water

[forbesy]

I regularly cross the Irish Sea between LHR and DUB, and whilst I'm no aircraft specialist, I get used to various sights and sounds on the way.

I'm no stranger to hearing the beep-beep-beep on final approach both coming into DUB and LHR, but the other day I heard it as we were on our initial descent over the Irish Sea. Does this mean the aircraft's systems thought we were too close to the water, or might it have been something else?

Incidentally, as a disclaimer of sorts, I'm no conspiracy theorist, and have full confidence in the abilities of all the uniformed staff on board, just after someone with knowledge/experience of the aircraft (A319) to give me a suggestion as to what it might have been.

Cheers!

[boardingpass]

Sitting at the front of the cabin, I often hear a little beep beep beep a minute or two before landing. Occasionally after landing and sometimes at random times during the flight. Pax often look quite concerned when they hear it, but I'm quite calm because I know what it means... The auto-pilot has been disengaged. So nothing to worry about at all.

[forbesy]

Ah nothing to do with how far the a/c is from the ground then? Fair enough, thanks!

[eastern wiseguy]

Too close to anything solid,or closing at too great a rate would precipitate a "WHOOP WHOOP PULL UP PULL UP" or "TERRAIN "...something along those lines...generally accompanied by a sharp increase in power followed by an upwards motion in the aircraft.:ok:

[AussieNick]

Too close to anything solid,or closing at too great a rate would precipitate a "WHOOP WHOOP PULL UP PULL UP" or "TERRAIN "...something along those lines...generally accompanied by a sharp increase in power followed by an upwards motion in the aircraft.http://images.ibsrv.net/ibsrv/res/src:www.pprune.org/get/images/smilies/thumbs.gif

usually followed quite closely by "oh shi......."

[Northbeach]

I do not fly the Airbus, so this answer is generic rather than aircraft specific. Ground proximity warnings are triggered by numerous things. For example: a rate of closure between the aircraft and the detected surface below (water/terrain), aircraft altitude with relationship to flap and/or landing gear position. And there are many others triggers rather than just detecting a hard surface ahead of the aircraft near/at/or above the aircraft’s altitude.
Additionally there are trim in motion sounds designed to alert the pilot to the trim changing (position of the horizontal stabilizer changing initiated by the pilot or the autopilot). And there are autopilot disconnects annunciations sounds. Without knowing the specific aircraft and hearing the specific beep-beep-beep it is difficult to be specific.
For what it is worth: fire warnings are usually bells (not Christmas happy sounds type), configuration problems are usually horns and system in motion/transition alerts some other unique sound.
On a side note Boeing really messed this up on the 737 (my opinion & the jet I fly). Boeing used the same horn to warn the pilot of pressurization problems, and aircraft configuration problems both on the ground and in flight. The same horn sounded either continually or intermittently. Do you think there is a chance for confusion there? The Helios accident brought this to light.
I hope this helps.

Respectfully,

[forbesy]

Thanks Northbeach et al. I guess it would make sense to have different types of sounds to signify different types of action required from the pilot/FO.

On a slightly related note, it's a shame post-9/11 the door to the cockpit is locked, I never got the chance to see a working cockpit as a child, and now I regularly fly I get the impression it's frowned on. Maybe I should ask, and hope to get sympathetic cabin crew/captain who are happy to show me what goes on.

[Capot]

usually followed quite closely by "oh shi......."


Really? Not in my experience; it's more a case of being followed by "Oh b****r, I sh*t myself............."

Together with the operation of the olfactory alarm sensor.

[Northbeach]

Forbesy,

“On a slightly related note, it's a shame post-9/11 the door to the cockpit is locked, I never got the chance to see a working cockpit as a child, and now I regularly fly I get the impression it's frowned on. Maybe I should ask, and hope to get sympathetic cabin crew/captain who are happy to show me what goes on.”

In-flight cockpit visits are more than just “frowned on” as they are prohibited by company regulations as well as federal law (USA). And it is a great shame. I am an airline Captain today because of numerous in-flight cockpit visits as a child. Once I saw an airliner flight deck in action I was hooked-for better or worse. Any western flight crew would be jeopardizing their career as well as facing possible jail time and a lifetime ban from working in the industry if they were to open the flight deck door and allow a passenger in without the proper credentials (need to be in the flight deck, work related, already employed by an approved agency, prior screening and previously arranged. You can’t simply fill out a form and get the credentials).

Recently I read about a series of DVDs (here on PPrune) take the viewer through a real flight on a modern airliner. I have no commercial interest in the DVDs and am therefore not trying to sell them. What reviews I read were quite positive. If you fly on a small commuter plane like a Beech 99, Islander, Twin Otter or 400 series Cessna outside the security crazy western world (unfortunate but necessary) you may be able to observe the pilots as the flight deck was not designed to be separate from the passengers. Go for an introductory flight lesson yourself and get a taste of flying. Finally there is YouTube, there are many videos of flight crews in action (the good, the bad, and the ugly-it’s all there).

Take care,

Respectfully

[UPP]

I only ask because I was travelling Club in the Med last year. The curtains were drawn shut, and then a boy of about 10 or 11 was ushered into the flight deck. The door was closed, and he was there for a good 20 minutes or so.

Given the airline involved, he was probably bosses relative or some such. I wasn't bothered. Obviously no terrorist. This airline always have the cockpit door open when pax are boarding right behind them, and I've known the door to be open at various times in the flight. Sometimes the Captain or F/O will come out and chat, mostly to their own nationals, but also other people. It's almost like the old days.

And in case that's not good, I'm not going to identify the airline.

So what is actually illegal, as opposed to frowned upon by various company SOPs?

[11Fan]

Are kids are ever allowed now?

……only if they like movies with gladiators in them.