Virgin 747 under escort to Canada
aka Capt PPRuNe
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Please give it a break. I am fed up of deleting 'Reginald E Spotter' type posts about revealing the hijack squawk code. It is not relevant and it is not secret. Anyone who believes it is or should be cannot be a serious contributor to these forums. 
So, can you either contribute to the debate without the references to whether the hijack squawk should be published or not or else go and find a conspiracy website. Having your efforts deleted will only cause frustration.
So, can you either contribute to the debate without the references to whether the hijack squawk should be published or not or else go and find a conspiracy website. Having your efforts deleted will only cause frustration.
Join Date: Mar 2001
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The transponder decided to do it's own thing, and was squawking 7500 even though a different code was actually being displayed in the selection window.
The flight had to divert to get the offending unit sorted out, as the US would not let the aircraft enter their airspace with the fault.
For info, it is part of the FAA rules that an aircraft with a faulty/inoperative transponder will not be allowed to enter US airspace....as I learnt a couple of years ago when our transponder went on the blink as we entered Canadian airspace off the ocean. Doh
The flight had to divert to get the offending unit sorted out, as the US would not let the aircraft enter their airspace with the fault.
For info, it is part of the FAA rules that an aircraft with a faulty/inoperative transponder will not be allowed to enter US airspace....as I learnt a couple of years ago when our transponder went on the blink as we entered Canadian airspace off the ocean. Doh
Join Date: Dec 1997
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Well it was bound to happen. Putting one wrong number in by mistake. How many times has it happened before 9/11 and been corrected with a call from atc and an apology from the crew. No need to lynch the crew guys, it could happen to anyone if they're tired or distracted. Maybe a time to review the software to require double entry of the hijack code. Whoever the crew was i'm feeling for you guys. Hope Virgin see it for what it is.
The full circumstances, any errors made, and any remedial actions necessary will be published in due course by the CAA . All those who need to know the information will no doubt have access to it. In the meantime, your speculation is mostly wrong and in some cases unhelpful
Not long ago in my long aviation career it was not considered a good idea to put anything into the box "starting with a 7" without going to standby first.
Despite modern technology I have always worried about the "modern merchants" on my flight deck who totally rely on the fact that "the time delay won't let anything unfortunate happen".
Not many years ago ATC were not allowed to issue codes starting with 7. Nowadays the VFR code is 7000. It does not take much of a fumble to come up with 7700!
In fact, during my "day job" I was recently given the code "7764" for departure (from somewhere in Germany) and that was a bit of a worry.
PS: Having just read the edict from Scroggs above, can I just tell him that I even have a Mode S in my "fun" aeroplane so I do know what I am talking about and have put my money where my mouth is!
Despite modern technology I have always worried about the "modern merchants" on my flight deck who totally rely on the fact that "the time delay won't let anything unfortunate happen".
Not many years ago ATC were not allowed to issue codes starting with 7. Nowadays the VFR code is 7000. It does not take much of a fumble to come up with 7700!
In fact, during my "day job" I was recently given the code "7764" for departure (from somewhere in Germany) and that was a bit of a worry.
PS: Having just read the edict from Scroggs above, can I just tell him that I even have a Mode S in my "fun" aeroplane so I do know what I am talking about and have put my money where my mouth is!
BOAC, you wrote:
quote:
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So put the XPDR to STBY when changing the squawk
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No No No! This has been done to death before on Pprune. We have been told ALL transponders have a 'pause' function when codes are being changed so it is deemed not to be necessary.
It WAS SOP in the RAF in the 70-80's but things have moved on since then.
I was told of this so-called 'pause' function and indeed taught for years that it existed. But it seems that the ground radar ARP is what actually causes a slight delay when detecting changed SSR codes - there is actually no such 'pause' function at all! I did a trial one day with a co-operative ATCU and asked the controller to tell me when he observed the SSR code change. He did - it was instantaneous.
Since then I've gone back to the old RAF SOP!
quote:
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So put the XPDR to STBY when changing the squawk
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No No No! This has been done to death before on Pprune. We have been told ALL transponders have a 'pause' function when codes are being changed so it is deemed not to be necessary.
It WAS SOP in the RAF in the 70-80's but things have moved on since then.
I was told of this so-called 'pause' function and indeed taught for years that it existed. But it seems that the ground radar ARP is what actually causes a slight delay when detecting changed SSR codes - there is actually no such 'pause' function at all! I did a trial one day with a co-operative ATCU and asked the controller to tell me when he observed the SSR code change. He did - it was instantaneous.
Since then I've gone back to the old RAF SOP!
Junior trash
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I thought they continued broadcasting the old squawk continuously until a bit after the new code has been entered, hence the instantaneous change on ATC screens. I've been told in groundschool on 2 types now to never ever put xpdr to standby when airborne as it will bugger up yours and everyone elses TCAS thats watching you possibly causing nuisance warnings due sudden pop-up and other undesirable consequences. Also ATC will lose your ssr trace.
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JW411 I think you have misunderstood me. In saying that several posts demonstrate a lack of knowledge of the equipment on the particular airframe in question, I am saying that unless you have flown that aircraft, you are forced into making assumptions about the equipment that is fitted. Many here have indulged in speculation based on assumptions driven by their experience of aeroplanes with other types of equipment, and many of the assumptions are wrong - and thus the speculation is meaningless.
I have flown the aircraft in question - the most recent occasion was yesterday. The equipment fitted is not the same as other aeroplanes - it's not even the same as our other A340-600s. I have not spoken to the crew involved in the incident, but I am aware of some of the issues. That is why I can tell you that your speculation is mostly inaccurate.
I have flown the aircraft in question - the most recent occasion was yesterday. The equipment fitted is not the same as other aeroplanes - it's not even the same as our other A340-600s. I have not spoken to the crew involved in the incident, but I am aware of some of the issues. That is why I can tell you that your speculation is mostly inaccurate.
I'm sorry dear boy, but could you tell me where exactly in my post was I speculating?
I rather thought it was more of a history lesson in common sense as we used to know it.
Indeed, I have to deal with THREE different transponder versions at work at the moment but they all have one thing in common - they all have a "standby function".
Don't yours? If not then it is very remiss of the manufacturers.
I rather thought it was more of a history lesson in common sense as we used to know it.
Indeed, I have to deal with THREE different transponder versions at work at the moment but they all have one thing in common - they all have a "standby function".
Don't yours? If not then it is very remiss of the manufacturers.
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JW411,
quote - 'Well it was bound to happen. Putting one wrong number in by mistake'. That comment was speculation because you don't know the kit installed on the aircraft. We are not talking about different transponder types here.
quote - 'Well it was bound to happen. Putting one wrong number in by mistake'. That comment was speculation because you don't know the kit installed on the aircraft. We are not talking about different transponder types here.
Per Ardua ad Astraeus
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Leaving aside this latest 'incident', the subject of whether to select 'standby' is one your (airline) SOPs should address for the aircraft type/s you fly. A couple of the previous threads are here and here. As you can see the topic is at best open to confusion.
My view is that care should be taken ANYWAY when selecting codes beginning with 7, and these threads highlight ways to do that. I'm sure that 'passing through' the '7s' will not trigger instantly - nor, I'm sure, would ATC (over)react to a resulting transient 'Emergency' type code squawk although it would, no doubt, focus their attention. I do NOT think selecting S/BY in a busy ATC/TCAS environment is sensible at all (unless ATC or SOP requested) and I would hope no-one does it.
My view is that care should be taken ANYWAY when selecting codes beginning with 7, and these threads highlight ways to do that. I'm sure that 'passing through' the '7s' will not trigger instantly - nor, I'm sure, would ATC (over)react to a resulting transient 'Emergency' type code squawk although it would, no doubt, focus their attention. I do NOT think selecting S/BY in a busy ATC/TCAS environment is sensible at all (unless ATC or SOP requested) and I would hope no-one does it.
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Our late model Collins Mode S transponders (forgot the model) have a built in delay that prevents a newly selected code from being transmitted immediately. This prevents any transient codes from being transmitted. Only the original code will be seen by ATC until 5 seconds after the new code is selected.
Secondly, because of ACAS (TCAS), you never want to select STANDBY while airborne.
Check 6
Secondly, because of ACAS (TCAS), you never want to select STANDBY while airborne.
Check 6
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JW411 your comment "Nowadays the VFR code is 7000. It does not take much of a fumble to come up with 7700!" suggests you beleive that the crew entered an incorrect code into the transponder head unit. In your post in reply to mine, you say, "Indeed, I have to deal with THREE different transponder versions at work at the moment but they all have one thing in common - they all have a "standby function. Don't yours? If not then it is very remiss of the manufacturers." This suggest to me that you are speculating that not only was an incorrect code was entered by the crew, but that it was done without putting the transponder head unit to standby.
Both comments confirm that you are indeed not familiar with the equipment fitted to this particular aircraft, however relevant they may be to the vast majority of airline equipment. Please wait until the CAA publish their summary of the incident, when you will understand where I am coming from.
Both comments confirm that you are indeed not familiar with the equipment fitted to this particular aircraft, however relevant they may be to the vast majority of airline equipment. Please wait until the CAA publish their summary of the incident, when you will understand where I am coming from.
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JW411, you are quite right, I misquoted and should have checked further before responding and for that I apologise.
Mind you your closing sentence nearly lost you your apology. At least my mistake contained no vitriol!
Coming back to the point, as scroggs suggests above, if you believe this is a question of operating a transponder like any other then you are probably barking up the wrong tree.
Mind you your closing sentence nearly lost you your apology. At least my mistake contained no vitriol!
Coming back to the point, as scroggs suggests above, if you believe this is a question of operating a transponder like any other then you are probably barking up the wrong tree.
Virginia Plane:
Thank you for that. I'm sorry if I was a bit abrupt but I was a bit hacked-off having someone else's remarks attributed to me.
scroggs:
You are reading things into my post which were not intended. I have nowhere suggested (in my mind anyway) that this incident was caused by a mis-selection by the crew. I have absolutely no way of knowing whether it was or not nor do I particularly care.
I thought I was just making a general point that there are Murphys out there. You have just chosen to misinterpret what was intended.
The finger-trouble suggestion was NOT made by me.
Thank you for that. I'm sorry if I was a bit abrupt but I was a bit hacked-off having someone else's remarks attributed to me.
scroggs:
You are reading things into my post which were not intended. I have nowhere suggested (in my mind anyway) that this incident was caused by a mis-selection by the crew. I have absolutely no way of knowing whether it was or not nor do I particularly care.
I thought I was just making a general point that there are Murphys out there. You have just chosen to misinterpret what was intended.
The finger-trouble suggestion was NOT made by me.
