# Are air marshals on every flight?

These guys say (in the discussion) that they were the only three passengers on board.

Does that mean that there was no Air Marshal on board (or one of them was?).

Aren't air marshals present on every flight?

• This sounds like the setup to the poker adage "Look around the table, if you can't identify the sucker, you are the sucker". It looks like the photo shows the 3 men in Economy class, since they flight attendants didn't let them go up to First Class for free, it's likely that there were already passengers in first class, perhaps the air marshalls were among them. – Johnny Mar 16 '15 at 20:16
• Specify 'every flight'. Every commercial flight? Every American commercial flight? Every international flight? What exactly are you asking? – Mast Mar 17 '15 at 15:31

The exact number of air marshals is not public information, and they certainly don't disclose what flights they fly on or other operational details. However, the number has been reported to be on the order of ~3,000-4,000 and reports indicate the number has decreased somewhat since then. All of them are, of course, not on duty 24/7/365. There are around 87,000 flights a day in the US alone, but only around 28,000 are commercial passenger flights, where air marshals are presumably most likely (hopefully there's not a need for air marshals on military flights, for instance).

So for some back of the envelope math, let's conservatively say there are 3,500 air marshals who all work five days a week, they all work alone (in reality, they appear to work at least in pairs), and they somehow manage to average protecting four flights a day. Even with these conservative assumptions, that would only be 5000 flights/day covered by air marshals. From this, it should be clear that there cannot possibly be an air marshal on every commercial flight in the US.

The President of the Air Marshal Association/CWA (their union), not entirely a disinterested party, agrees:

"There are around 30,000 commercial flights per day over the U.S.," says Casaretti. "If you were to attempt to place a team of just two FAMs on each flight, it would require an agency of over 75,000 FAMs (accounting for training and days off). FAMs cover a very small percentage of commercial flights."

Which flight air marshals get on is determined by a computer program that assesses the probability of threat based on the aircraft, departure and destination cities, as well as the amount of fuel on board. This is the threat matrix that comes out of the missions operation center.

The TSA will not release statistics on the number of air marshals. TSA's Pascarella acknowledges only "many thousands." But Biles estimates that there are approximately 3,300 FAMs and of those, 34% are filling ground assignments in training, operations and management.

"We call them 'chair marshals,' riding out their career in management," says Biles. That leaves 66% of the workforce to perform in-flight security duties.

"If one accounts for vacations, sick leave, medical leave and days off, some air marshals working in operations have told me that this accounts for less than one half percent of all U.S.-flagged aircraft being covered by federal air marshals," he says.

• "less than one half percent of all U.S.-flagged aircraft" This is, of course, a meaningless statistic, since many US-flagged aircraft aren't on commercial flights. – David Richerby Mar 16 '15 at 9:49
• David, how is that meaningless? You seem to know exactly what that statistic meant... Enough to complain about it. – er mershel Mar 16 '15 at 15:05
• @ermershel It's meaningless because air marshals aren't supposed to be covering non-commercial flights. It's a true statistic, but one that is ultimately irrelevant (though it's designed to sound relevant in order to exaggerate the actual situation.) This would be like saying TSA only scans passengers at 10% of U.S. airports while failing to mention that that 10% happens to be all of the airports with scheduled passenger service (I just made that number up for example... I'm not sure what the actual percentage is.) – reirab Mar 16 '15 at 16:37
• Ah.. An irrelevant, not meaningless statistic, then. – er mershel Mar 16 '15 at 18:47
• That's why I said the head of the Air Marshal Association/CWA is not exactly a disinterested party here. The statistic implies that air marshals cover a dangerously low number of flights, but the universe of flights being considered includes everything from passenger jets a few miles from the White House into DCA to a crop duster in an Iowa field. Of course, there's also the random deterrence theory. You don't know whether an air marshal is on board a given flight, so, as the theory goes, it's not worth risking that one is present. The same applies to transit fare inspections, for instance. – Zach Lipton Mar 16 '15 at 20:46

Air marshalls are not on every flight. I was recently at a computer science seminar by Milind Tambe, whose research team developed the software that the Federal Air Marshal Service uses to randomly choose which flights get marshals. (It's also used for security patrols at LAX, coastguard patrols at various ports and even for anti-poaching patrols in Uganda's national parks.) Note that "randomly" doesn't mean uniformly at random: certain flights are more likely to be covered than others, depending on the perceived level of threat. But the fact that they choose which flights get marshals clearly means that some flights don't.

For those who are interested, Prof. Tambe's website has a lot of information, including some explanatory videos.

Air marshals are certainly not on every flight. With 80,000 flights daily in North America it would be nearly impossible, and most flights are low-risk. Billings, MT to Denver, CO in a Dash-8 simply isn't worth the effort to either police it or hijack it.

Higher ratios of marshals to flights will be found going into the major centers, and it likely approaches 1:1 going into the DC area.

• Billings, MT to Denver, CO in a Dash-8 simply isn't worth the effort to either police it or hijack it. That depends on your objective. If a bad guy really wanted to incite random terror, picking on a soft target that's supposed to be so boring as to be beneath notice would be a really effective way to accomplish it. Just saying. – Mason Wheeler Mar 16 '15 at 16:09
• Don't tell C.O.B.R.A. – Dronz Mar 16 '15 at 20:09
• That's a fair point @MasonWheeler. Of course, said bad guy could pick any number of targets with less security than aviation too. The real change though is in the attitude toward hijacking. Post-9/11, passengers and crews are prepared to do whatever they possibly can to defend themselves against an attack on board. There's no longer much reason to believe that everybody can cooperate and get away unharmed. While that change doesn't eliminate all threats to aviation, it would make it much harder for anybody to pull of a 9/11-style attack today. – Zach Lipton Mar 16 '15 at 20:53
• @Zach: Agreed. The 9/11 attack was a hack, a trick that could work exactly once. But that doesn't mean they couldn't try something else. – Mason Wheeler Mar 16 '15 at 20:57