And I interpret his "swift reaction" as the typical knee-jerk kabuki security that it is... one year later, the plot unravelled as untenable, yet now we're not only still dumping our water but having to face separating out all our electronics. Thanks, Comrade Chertoff. :mad:

All part of Skeletor's plan to take things over. :td:

A year later, people are starting to get tired of it so he has to stir up fear and "remind" people why it's there to keep the sheeple in check.

I think Chertoff is full of crap too, but your earlier contrention that EVERY independent expert has called the plot untenable is equally lame. Like I said, hyperbole is an equal opportunity propoganda tool. Chertoff is a tool for letting the airlines use him as a tool though. Tools everywhere.

Please correct me if I'm wrong but doesn't the pressurization of the plane prevent the altimeter from working?

Even in pressurized cabins or when cargo holds are pressurized, pressure will vary from that found at sea-level or at actual ground location to sufficient degree that I wouldn't be surprised if a trigger could go off that way.

Pressurization cycles, pressurization cycles. ;)

not in the baggage hold (or at least in the unpressurized section) and we all know how well cargo is screened.....:rolleyes:

No, at typical cruise the cabin altitude will have risen to the about 8000ft.

Sure, but above that won't be read, unless, like Goalie said, it's in cargo.

But then again, he stops hockey pucks for a living so take it for what it's worth. ;)

Aren't there more than one type of altimeter? In any case, pressure altimeters can be used as triggers in more than one way and is why I mentioned pressurization cycles.

Cargo loaded onto passenger planes could be screened via a simulated pressurization cycle contraption but that's another one of those things that I don't see DHS doing in any meaningful way today or tomorrow.

Apparently so. http://amsglossary.allenpress.com/gl...?id=altimeter1

That may be, but the one's that measure pressurized air would be worthless if you're planning to blow it up in air because the air is pressurized on the ground prior to takeoff.

And as for cargo, agree completely. It's something I've long complained about.

ah, the love of flyertalk family :D

phhhhhhttttttt ;)

and i wish it was for a living....i do it for fun [and no, don't start ;)]
:)

I wouldn't be certain about that. Even with pressurization of cabins on the ground, there's a pressurization cycle that takes place inside a pressurized cabin of commercial planes which wouldn't take a genius to exploit as part of an altimeter trigger.

In any case, there's the window of the cargo hold.

By the way, was Chertoff or Ridge DHS Secretary when the paranoia about watches with altimeters was being spread about town? That was Ridge there then if I remember correctly.

Every major airport in the US is well below 8000ft ASL, so an 8000ft trigger would be effective. Just wouldn't have so far to fall in Denver.

All cargo holds in modern airliners are pressurised too (remember the DC-10 blowouts ?) so it wouldn't matter where the device was.

Aircraft cabins are not pressurized before takeoff - the pressurization is caused by a differential effect. The difference in pressure on the inside vs. the outside is what 'pressurizes' the fuselage and the degree of pressurization is an aircraft engineering limitation as each cycle adds stress to the airframe.

By using composite materials (legacy airframes are pretty much all aluminum), Boeing was able to increase the pressure differential on the upcoming 787 - the higher the differential, the lower the cabin altitude relative to the outside altitude.

Air is constantly coming into the airframe, provided by air bled from the engines and processed through heating/cooling systems, while leaking out through expansion vents and various seals, so pressurization is a dynamic condition - it must be actively maintained via the venting system.

The highest commercial service airport that I know of is Denver, which is comfortably below 5,500ft. The average cabin altitude of most legacy (older than 73G/777/764) aircraft is around 8,000ft, sometimes as high as 10K depending on the cruise altitude - the higher the cruise altitude, the higher the cabin altitude. Newer aircraft rarely go above 8,000ft.

A bomb with an altitude trigger set for 6,000ft would not have a problem detecting that condition and detonating once the aircraft climbed above 6,000 + the differential setting.

Thanks for your vote of support. :rolleyes:

I have yet to see a single independent expert cited in any media reports as giving credence to the liquid bomb "plot." Those which have been interviewed have all cast extreme skepticism and doubt upon any homemade binary explosives for reasons people have mentioned more times here than is worth repeating, and the commercial ones are all easily caught by ETD (not to mention would not pass for any sort of legit liquid under any scrutiny).

Surely, if there were independent experts who believed in the threat of the liquid-bombing "plot," they'd have either come forward or been brought forward by now. So far, all we get are vague statements from Chertoff and company stating, "Our experts have assured us it was a legitimate threat, but we can't say anything about why--just take our words for it." :rolleyes:

Yeah, and I have a bridge in Brooklyn along with a nice tract of land in the Everglades I'd like to sell.

Depends.

A barometric altimeter wouldn't work if you tried to set it for, say, 30k feet, since most of the plane would be pressurized to a much lower altitude than that. But, as others have pointed out, setting it to around 8k feet would work, although it would cause the plane to explode not long after takeoff.

I'm not sure a GPS-based altimeter would be able to get any sort of reception to work inside a cargo package and inside the hold, but that's what dry runs are for: ship a GPS-based one and have it set to record its maximum altitude reading, then check it when you receive the shipment. You'd then see how well it worked, if it recorded any sort of high reading.

There are more exotic ones available as well, though they'd be much costlier--but still commercially available, not needing to be homemade.

There's always the cheap cell phones that can be used for triggers as well. Placed in or behind a thick stack of magazines or books, such a device as trigger being missed at airports from which our planes take off from too would not surprise me.

While Chertoff is wasting our money by way of this war on liquids and gels, cargo remains a rather ignored elephant.

Ah, I think my brain may melt now.....;)

Thanks for trying to explain it to me anyway. I'm just a flatfoot. I'm a tough audience...;)

Two simple words: Kabuki security. Passengers see diligent TSA screeners finding the dangerous shampoo. But passengers would not see cargo screening. Why bother to screen cargo, then, if passengers will not be dazzled by that activity?

Ridiculous indeed! Living near YVR and flying out of there many times, I'll never forget what happened more than 20 years ago:

http://www.flight182.com/

Surely this matter is sub judice. Articles like this cannot help justice for the accused. After all whether we agree with them or not the accused are entitled to a fair trial.

Out of those initially arrested around a year ago, how many are in trial right now or have been convicted since last summer?

Chertoff is free to run his mouth in the US and have journalists peddle that. Also, weren't nearly all of those arrested on this matter beyond the US? If people outside the US were to take everything Chertoff says and does seriously, I would hold their judgment to be suspect.

Not compelety true. Some aircraft do a small pressure differential before t/o. The differential is usually around .11-.15 psi


Not even close. Bogota is 8300', Rio Negro 7200' and many more in South Amercia that are higher. LXV - Leadville is the highest public airport in the US at 9927' and TEX-Telluride 9078' being the highest with commerical service. Aspen @ 7815', Durango 6685', Hayden-Steamboat Springs @6878' and a few more that I cant remember.

Cabin altitude ranges from 4400 feet(27K feet actual A/C altitude) to 8000 feet(41K feet actual A/C altitude). If we should happen to hit 10,000' a horn will sound in the cockpit and if the cabin continues to climb all of the pax O2 mask will fall automatically (we call it the rubber jungle.) Most airliners cruise in the mid 30s.

A GPS has an antenna that needs to be able to "see" that satelites. How would it be able to "see" if it is in a shipping box or crate?

Interesting, learn a new thing everyday about airports in the US at least. :) [He did say (with bold added for purposes of demonstration): "The highest commercial service airport that I know of is Denver, which is comfortably below 5,500ft."]

Out of the airports above, I've flown into only three of those and only one of those commercially.

I've landed and taken off from higher airports -- for Asia, in India, China and Tajikistan; for South America, in Argentina, Chile and Peru.

They were so close to carrying out this dastardly plot, that 3 of them did not even have passports.

What memory. Do not make it up!!

16 of the 24 questioned have been charged. 2 of these discharged last November and the remaining 14 to go to trial in 2008. On remand and in custody.

Remember police found explosive materials and detonators in their homes.

One of the higher ups was caught in Pakistan and others are still loose

Out of the individuals arrested in the UK at the time for this "plot would have killed thousands", how many have been convicted for the plot itself and/or are still sitting in a jail/prison since the moment they were initially rounded up by the police in the UK last year?

Bangda, Tibet: 14,219'. Highest commercial airport in the world (at least according to Boeing....): http://www.boeing.com/news/releases/...se.950501.html

Who said I was making it up? I was asking. :rolleyes:

Link please to their charges and status of their trials. Show me YOU'RE not making it up.

The same way a GPS antenna can still receive a signal inside a plane, or inside a car, without an externally-mounted antenna. Even my handheld hiking unit with its horizon-only antenna is able to "see" satellites indoors if near a wall or window, though the signal is much weaker than out in the open air.

Commercial units with both horizon and overhead antennas and with better antennas than the tiny one in my handheld unit could potentially receive enough of a signal from in the plane's cargo hold so as to function.

And note that I did specify that a "dry run" through shipping the unit would be necessary to test out whether or not it would work--that's why I said I'm not sure.

Agreed, but likely to equalize once the aircraft climbs out and not sufficient to push the cabin altitude higher - it would push it slightly lower. Given most differentials are in the 7.x-8.x range, a .11-.15 difference is not significant. Law Dawg was asking if the aircraft was fully pressurized for altitude before leaving the ground, which it's not.

I was referring to major domestic US airports, but you're correct as I totally forgot about ski country. JAC has commercial jet service (in season) and has an elevation of 6451Ft, which is much higher than DEN - but again, it's a regional airport with limited commercial service and unlikely to be a terrorist target.

Agreed for most newer aircraft, but some legacy aircraft allowed for higher cabin altitudes of up to 10K. It's unlikely someone can fly one present-day in the US, but some still fly overseas.

Indeed--I suspect most airports from which terrorists would plot to stage a bombing are near sea level, places like JFK, IAD, LAX, etc.

Couldn't one set the barometric altimeter such that when it reached its trigger point of 8,000', that instead of detonating an explosive it could trigger a timer that would start an hour (or whatever time frame) countdown that would then trigger the explosive at cruising altitude? If only all air cargo was screened. :(

You could indeed, though adding the timer does make it a bit more complicated, and thus introduces more potential for failure.

Yes, so far the terrorists have not demonstrated an ability to think 'outside the box'. Which is fortunate, because I don't think the DHS has either.

Attacking a 2nd-tier airport would probably generate more terror than attacking one of the likely targets. Shows you're not safe anywhere.

La Paz, Bolivia. It was like being punched in the stomach.

I saw this on the news and when they said 3.5 oz was immediately determined as safe all's I could think of how many 3.5 oz containers I could stuff in my 1 quart baggy. I don't understand if you can buy a larger container after the security checkpoint.

Quote:
Originally Posted by Superguy
Just to refresh my memory ... weren't they all released?

When you use the phrase in red you are implying that you have a vague memory of them all being released and want someone to confirm. Is that not making it up when in fact they were not all released and there is no source to back it up.

I suggest you do a google search for "British Airline Bombers" and read some of the articles including this one in the NY Times which you cannot deny is a liberal paper and therefore not conservative propaganda

http://www.nytimes.com/2006/08/28/wo...rssnyt&emc=rss