6 ms·

My cousin in the early 2000s worked for a R&D company who did some work on the early generation of sniffer machines that detected trace residue of explosives, a

My cousin in the early 2000s worked for a R&D company who did some work on the early generation of sniffer machines that detected trace residue of explosives, and biological agents in airports. He had to go to a meeting and flew from Atlanta to boston with a prototype of the machine. He packed it in his carry on case along with his basic tool kit. When he got to security screening he realized that he also had vials of simulants for anthrax, sarain, various explosives, etc etc in that case. He gets into the security screening line and the TSA guy starts asking him all kinds of questions and he just knows he is about to get detained for the simulants which were not clearly marked as such. Instead the guy is like “You can’t take that screw driver with you”

dragontamer 8y ago
This was figured out in an Dept. Homeland Security "red team" test of the TSA a few years ago, where the TSA failed like 95%+ of the tests against them: https://abcnews.go.com/US/exclusive-undercover-dhs-tests-find-widespread-security-failures/story?id=31434881 https://abcnews.go.com/US/exclusive-undercover-dhs-tests-fin... I think the TSA has switched strategies recently, and they've been improving since then. But ultimately, its not the "bag check" where the TSA catches goons, its the random more intense check that they do these days. And sure, going from 95% failure to 80% failure isn't much of an improvement, but its still going to change the calculus of an attacker. When you have a 20% chance of failure before you even board the airplane, that's an issue to your plans. Furthermore, TSA includes air marshals and the Israeli-style "behavioral" cops who are scanning airports. These are the more successful cops at the job, and the ones we are relying upon for real. I wouldn't discount the entirety of the TSA just because of the failures of the bag-check program. Again, US Air marshals (armed cops who sit on every aircraft secretly with plain-clothes) are under the TSA and I think the US Air Marshals contributes a LOT to our real security. Unfortunately, the bag-check thing is mostly security theater, but at the same time, the more "serious" checks vs attackers are more hidden and less well known (as it should be). But security theater might be enough to discourage an attack, or at very least cause our enemies to focus on the bag-check (when our REAL security really lies with other programs). So its a useful distraction IMO. There's a bit of "wink-wink lets not talk about this" going on that you need to understand though.
- deleted 8y ago
  [deleted]
- fosk 8y ago
  > US Air marshals (armed cops who sit on every aircraft secretly with plain-clothes) Do they really sit on every flight?
  - Tushon 8y ago
    No, just on the basic numbers we have available, it would not be possible. https://aviation.stackexchange.com/questions/13264/are-air-marshals-on-every-flight https://aviation.stackexchange.com/questions/13264/are-air-m...
  - Rebelgecko 8y ago
    No. The percentage of flights with air marshals is in the low single digits.
    - knz 8y ago
      Which makes sense. A JFK to AMS flight is probably a much higher risk for terrorism than say FSD to MOT.
      - Rebelgecko 8y ago
        According to the article I read, they're actually less common on flights out of NY and Washington DC- there were pilots complaining that they hadn't seen an air marshal in 6+ months. It sounds like they avoid putting marshals on flights that have other law enforcement officers on them, which is going to be a good chunk of the domestic flights to/from big cities
  - Someone1234 8y ago
    Nope, but I've had one sit next to me before on a US bound international flight (in 2005 ish). So they definitely exist.
RyJones 8y ago
Sniffers only detect tagged explosives that are carelessly handled.
- ericcumbee 8y ago
  I don’t know where or what happened with this machine, as he was the technical lead for his company and they were a sub-contractor on the machine. But it was supposed to be a lot more sensitive accurate and smaller than what they had at the time. From my understanding they completed their part of the contract and never heard anything else about it.
  - RyJones 8y ago
    I think it is an unsolvable problem. There's nothing particular about explosives that makes them easy to discriminate from non-explosives. I'd love to be proven wrong, though.
    - philipkglass 8y ago
      The vast majority of explosives can be quickly differentiated from non-explosives by gas chromatography-mass spectrometry. The main practical impediment to detecting concealed explosive material is that some of the explosive substance needs to pass through the GC-MS to be detected. So an explosive with extremely low vapor pressure (e.g. pure PETN) will not be readily detected this way. Plastic explosives made from PETN are more readily detectable, because the plasticizers are more volatile than PETN itself. GC-MS also won't work if the explosive is hermetically sealed so that none of it can reach the detector. There are also methods based on e.g. terahertz spectroscopy, but AFAIK GC-MS is the most specific and common method of identifying explosive materials.
      - facetube 8y ago
        They actually test for both components of binary explosives in the US TSA. Source: a TSA agent, while he was going through all of my things because I guess I touched a cleaning product with ammonia in it or something.
matwood 8y ago
I have an engraved money clip that happens to have a small 2" maybe pocket knife on it. I would routinely forget to leave it at home, and after the 3rd time of spending $20 to mail it back to myself I finally stopped carrying it. I'll never forget one TSA agent who accusatorially said he didn't think I was purposely trying to break the law because it was engraved. Don't even get me started how often my wife gets 'flagged' for extra security.
- pavel_lishin 8y ago
  I've carried a knife blade (approximately an inch), and a screwdriver-type tool onto flights with zero issues many times. I have had to mail back a Leatherman supertool, and since then have never brought it.

dragontamer 8y ago

This was figured out in an Dept. Homeland Security "red team" test of the TSA a few years ago, where the TSA failed like 95%+ of the tests against them: https://abcnews.go.com/US/exclusive-undercover-dhs-tests-find-widespread-security-failures/story?id=31434881 https://abcnews.go.com/US/exclusive-undercover-dhs-tests-fin... I think the TSA has switched strategies recently, and they've been improving since then. But ultimately, its not the "bag check" where the TSA catches goons, its the random more intense check that they do these days. And sure, going from 95% failure to 80% failure isn't much of an improvement, but its still going to change the calculus of an attacker. When you have a 20% chance of failure before you even board the airplane, that's an issue to your plans. Furthermore, TSA includes air marshals and the Israeli-style "behavioral" cops who are scanning airports. These are the more successful cops at the job, and the ones we are relying upon for real. I wouldn't discount the entirety of the TSA just because of the failures of the bag-check program. Again, US Air marshals (armed cops who sit on every aircraft secretly with plain-clothes) are under the TSA and I think the US Air Marshals contributes a LOT to our real security. Unfortunately, the bag-check thing is mostly security theater, but at the same time, the more "serious" checks vs attackers are more hidden and less well known (as it should be). But security theater might be enough to discourage an attack, or at very least cause our enemies to focus on the bag-check (when our REAL security really lies with other programs). So its a useful distraction IMO. There's a bit of "wink-wink lets not talk about this" going on that you need to understand though.

deleted 8y ago
[deleted]
fosk 8y ago
> US Air marshals (armed cops who sit on every aircraft secretly with plain-clothes) Do they really sit on every flight?
- Tushon 8y ago
  No, just on the basic numbers we have available, it would not be possible. https://aviation.stackexchange.com/questions/13264/are-air-marshals-on-every-flight https://aviation.stackexchange.com/questions/13264/are-air-m...
- Rebelgecko 8y ago
  No. The percentage of flights with air marshals is in the low single digits.
  - knz 8y ago
    Which makes sense. A JFK to AMS flight is probably a much higher risk for terrorism than say FSD to MOT.
    - Rebelgecko 8y ago
      According to the article I read, they're actually less common on flights out of NY and Washington DC- there were pilots complaining that they hadn't seen an air marshal in 6+ months. It sounds like they avoid putting marshals on flights that have other law enforcement officers on them, which is going to be a good chunk of the domestic flights to/from big cities
- Someone1234 8y ago
  Nope, but I've had one sit next to me before on a US bound international flight (in 2005 ish). So they definitely exist.

RyJones 8y ago

Sniffers only detect tagged explosives that are carelessly handled.

ericcumbee 8y ago
I don’t know where or what happened with this machine, as he was the technical lead for his company and they were a sub-contractor on the machine. But it was supposed to be a lot more sensitive accurate and smaller than what they had at the time. From my understanding they completed their part of the contract and never heard anything else about it.
- RyJones 8y ago
  I think it is an unsolvable problem. There's nothing particular about explosives that makes them easy to discriminate from non-explosives. I'd love to be proven wrong, though.
  - philipkglass 8y ago
    The vast majority of explosives can be quickly differentiated from non-explosives by gas chromatography-mass spectrometry. The main practical impediment to detecting concealed explosive material is that some of the explosive substance needs to pass through the GC-MS to be detected. So an explosive with extremely low vapor pressure (e.g. pure PETN) will not be readily detected this way. Plastic explosives made from PETN are more readily detectable, because the plasticizers are more volatile than PETN itself. GC-MS also won't work if the explosive is hermetically sealed so that none of it can reach the detector. There are also methods based on e.g. terahertz spectroscopy, but AFAIK GC-MS is the most specific and common method of identifying explosive materials.
    - facetube 8y ago
      They actually test for both components of binary explosives in the US TSA. Source: a TSA agent, while he was going through all of my things because I guess I touched a cleaning product with ammonia in it or something.

matwood 8y ago

I have an engraved money clip that happens to have a small 2" maybe pocket knife on it. I would routinely forget to leave it at home, and after the 3rd time of spending $20 to mail it back to myself I finally stopped carrying it. I'll never forget one TSA agent who accusatorially said he didn't think I was purposely trying to break the law because it was engraved. Don't even get me started how often my wife gets 'flagged' for extra security.

pavel_lishin 8y ago
I've carried a knife blade (approximately an inch), and a screwdriver-type tool onto flights with zero issues many times. I have had to mail back a Leatherman supertool, and since then have never brought it.