Making Another 9/11 Impossible

I'm tired of headlines like this:

New autopilot "will make another 9/11 impossible"

Why are people so narrowly focused? The goal isn't to protect against another 9/11. The goal is to protect against another horrific terrorist incident.

Stop focusing on the tactics, people. Look at the broad threats.

I've written about this particular countermeasure before.

Posted on March 15, 2007 at 7:42 AM • 55 Comments


Eric K.March 15, 2007 8:00 AM

Homeland Security: Specializing in Tactical Band-aids for Strategic Problems.

Trichinosis USAMarch 15, 2007 8:09 AM

EXPENSIVE tactical bandaids, mind you. Those popcorn machines in the midwest need protecting, gol dang it!!! We could ostensibly have a Real Genius situation on our hands otherwise!

DeweyMarch 15, 2007 8:12 AM


So now all someone has to do to hijack a bunch of airplanes will be

a) Take over a fixed, known location ground target, or break into the network.
b) Put a bunch of "terrorist" in the airplane who have only to hit the cockpit door real hard, automatically giving control to said ground location.

Hmmm. I think there may just be a Denial of Service attack here also. 1 jammer, 1 slam of door and who flies the airplane? Or, maybe, slam 30 doors simultaneously. I wonder how many standby pilots they'll have on the ground...

I also wonder how you test this system pre-flight? Is this switch on the door (or control panel) normally open or normally closed and what happens when you get short pulling it the wrong way?

I wonder what will happen the first time the NTSB identifies this system as a contributing factor to a fatal accident.

markMarch 15, 2007 8:28 AM

On the other hand now that they have made it 'impossible' perhaps they could focus on something else.

Anonymous PilotMarch 15, 2007 8:29 AM

I am a pilot for the 777. In the event of a fire in the avionics, I, as a pilot *must* be able to pull the circuit breaker for all unnecessary avionics. If this system is to be installed, I would lose control of *MY* OWN PLANE. Imagine if a fire broke out in my avionics. I could not be able to shut down some of them. The risks outweigh the nonexistent benefits.

Tim RMarch 15, 2007 9:02 AM

Homeland Security kind of reminds me of the two guys on the Guinness ads here in the states....

HS#1: I know, we'll spend a ton of money to inconvenience people and create an air of security that doesn't actually work.

HS#2: Spend a ton of money? BRILLIANT!

JimMarch 15, 2007 9:08 AM

Spot on, Dewey!!! Terrorism is like a game of chess. You win when you can plan more moves in advance than your opponent can, and right now Homeland Security is not thinking that far ahead in the game.

ThuktunMarch 15, 2007 9:14 AM

The chess metaphor seems apt. Having been utterly blindsided by a Fool's Mate[1], Homeland Security is spending effort trying only to defend against the Fool's Mate, rather than improving chess skills for the variety of attacks that are possible.


MartinMarch 15, 2007 9:16 AM

There's a very easy way to "make another 9/11 impossible": Remove that date from the calendar.

Stephan SamuelMarch 15, 2007 9:21 AM

If the plane can fly itself, or we can fly it from the ground, why even have the pilot in there? For that matter, why have a plane? I'm gonna patent a huge slingshot that will fling people across the pond. When airplanes are eliminated, there will never be another 9/11-style attack (although, as calendar pointed out, 9/11 will occur for a day each year).

Oh, no... wait... we need the pilot.

AleMarch 15, 2007 9:23 AM


The main difference between terrorism and a game of chess is that humans (including terrorists) change the rules as the game unfolds. Thus, planning ahead in a chess-like manner is pointless.

It is much better to eliminate this rule-bending advantage: let the countermeasures be generic enough so that they apply to broad sets of threats, and not single movie plots.

Ed KohlerMarch 15, 2007 9:45 AM

What if the goal of 9/11 was to get the United States to piss away billions of dollars on unnecessary security rather than the kind of things that would allow the country to continue to be the world's most powerful country, like education and health care? How are we preventing that?

JimMarch 15, 2007 9:55 AM

@ Ale

Spoken like a true Homeland Security agent. To the terrorist, the only rule that applies is that any human created or conceived rule need not be followed. For example you seem to think that before 9/11 the rule was that if you hijack a plane then you must ask for 20 million dollars and free airspace to Cuba and that the hijackers did not follow this rule. But this rule obviously did not apply to the 9/11 terrorists and never did. The narrow mindedness of thinking that there are rules of conduct in terrorism is the exact reason that this kind of action / response mentality will fail.

I hate to use this phrase but HS needs to "think outside the box." Yes, this may lead to more of Bruce's "movie plot" scenarios. If you at least consider the possibilities, though, you might have a chance at preventing an attack rather than having to say "Who would have thought..." in retrospect.

XokeMarch 15, 2007 10:29 AM


But what about all the children with a birthday on 9/11? Oh think of the children you communist^W terrorist!

A few decades ago it was the threat of communists, now it's the threat of terrorists. Seems there will always be something to 'fear'.

Mark J.March 15, 2007 10:33 AM

"It will be activated by the pilot flicking a simple switch or by pressure sensors fitted to the cockpit door that will respond to any excessive force as terrorists try to break into the flight deck.

Once triggered, *no one on board will be able to deactivate the system.* Currently, all autopilots are manually switched on and off at the discretion of pilots."

This sounds like a single point of failure. A glitch in the door pressure switch at a critical moment and suddenly no one is flying the plane. Cool.

AlanMarch 15, 2007 10:36 AM

There will always be something to fear as long as there's money in it for the military-industrial complex.

False DataMarch 15, 2007 10:46 AM

It seems like if this system were to activate during takeoff or landing, things could get very interesting very quickly. I wonder what impact that risk will have on operating procedures.

derfMarch 15, 2007 10:51 AM

Y'all aren't thinking of the benefits to society. Think about this system coupled with the anti-missile systems:

For example, your city is having a fireworks display on New Years Eve, but you want something new and exciting. Your average 14 year old could take control of a nearby 747 and have it do a flyover while doing barrel rolls and shooting off chaff.

RoyMarch 15, 2007 10:59 AM

There's the question of what if the hijacker gets to the cockpit without the automation taking over.

The answer to that will be a battle short from the ground end, where the ground controller can initiate the takeover sequence and fly the plane.

Which of course opens the door to some miscreant on the ground, or in the passenger compartment, hacking into the override control and thereby taking over the aircraft.

AnonymousMarch 15, 2007 11:11 AM

Bruce, it sounds like you're getting tired..

It constantly amazes me that we have a single issue into which every elected official is willing to pour unlimited amounts of money, yet nobody is actually applying the slightest amount of thinking to the issue. How does that happen?

XokeMarch 15, 2007 11:20 AM

Simple to stop - to prevent problems on the ground you can put an override control in the plane to prevent someone from the ground taking over the plane. Give it a few years (and a few more hundred million) and someone will come up with this idea ;)

Statist PresumptionMarch 15, 2007 11:27 AM


"It constantly amazes me that we have a single issue into which every elected official is willing to pour unlimited amounts of money, yet nobody is actually applying the slightest amount of thinking to the issue. How does that happen?"

You honestly don't know? I'll give you a clue: it's not their money.

bobMarch 15, 2007 11:35 AM

So now all I have to do to cause huge disruption to the lives of everyone on a plane is disturb the cockpit door? What are the penalties for "accidentally" crashing into the cockpit door while exiting the lavatory?

MarkMarch 15, 2007 11:46 AM

If the idea is to fly the plane remotely it's going to take a fairly high bandwith data link to send both live video and all the cockpit instruments to a so that someone has even a chance of flying the plane as well as the regular flight crew.
If the system is intended to be self contained what's it going to do sqawk 7700 and attempt peform an autoland at some random runway.
In the process ignoring ATC and TCAS, without even "knowing" if the navigational aids it is using are giving useful data or if the runway it intends to use is in service and clear of other traffic.
It appears that the greater risk is that such a system could cause a crash. Either directly through its operation or by causing pilots to try drastic steps (e.g. disconnecting all of the main generators) to regain control of their aircraft.
That's before you even considering that such a system might make it easier to turn an airliner into a guided missile.

Erik NMarch 15, 2007 12:03 PM

This sounds very much like your previous post

While a lot of stuff gets funded and done with reference to terror, I think these ideas should not be discarded blindly. OK, they won't save us from terrorism. They will prevent old tactics, but also, they may be useful in other situations:

In my reply to previous post I referred to a crash caused by falling cabin pressure. If pilots faint, remote control could save lives.

But, also, on falling cabin pressure, the autopilot ought to automatically search lower altitudes.

Already thought of in 2000...March 15, 2007 12:03 PM

Doesn't anyone remember the opening episode of the short-lived FOX series "The Lone Gunman?" back in pre 9-11 2000/2001?

A new remote control technology is installed in airlines to prevent hijackings... its taken over by terrorists/evil government conspirators and the plane is aimed at ... the world trade center in NY...

The heroes override it at the last minute and avoid a disaster...

Matthew SkalaMarch 15, 2007 12:50 PM

Stephan Samuel: Let me know when you have that slingshot patent application ready; there's a Dilbert strip I'll want to submit as prior art.

What we need is for cartoonists to predict all the OTHER stupid security ideas people will try, so that we can have them ready when they get proposed in earnest.

markmMarch 15, 2007 1:23 PM

As a former avionics technician, I suspect this idea would cause more crashes than there ever were successful hijackings...

The PeachMarch 15, 2007 1:32 PM

this auto-pilot system is coded like a rootkit (remember Sony?) inside the airplane OS/hardware. and hopefully it won't run M$' OS. So detecting it will be quite hard. another problem (as addressed by many before me) is "who is taking control on the ground?" and "how many ground rootkit control are there?". Quite interesting issue.

ZwackMarch 15, 2007 1:46 PM


Why are we spending so much time and money to "prevent another 9/11" when that tactic expired on 9/11/2001.

On that day four planes were hijacked. After the first three had been crashed into their targets the passengers on the fourth plane realised that for the greater good they needed to stop the hijackers. and they did.

Sure, they died, but they stopped the hijackers. So on any given flight do you think the passengers will allow a hijacking now, or do you think that they will fight back?

The tactics of 9/11 will not be used again, different tactics will be used next time.


a private pilotMarch 15, 2007 2:41 PM

Though I only fly small aircraft, I would never fly anything equipped like this.

There are so many ways that the system could go wrong. You could wind up with a airplane that no one was flying. And all that would take is a simple software error, such as are reported almost every day in major transportation systems.

UNTERMarch 15, 2007 3:16 PM


Sorry, it's just insane to say that "they" don't follow "rules". Of course they do - they have a goal they are trying to advance, namely expel the US from the Middle East, collapse US influence over the world, and implement a neo-caliphate. Therefore, we know they won't do certain things: they won't throw money on the stock exchange floor to cause disruption, for example.

In large part, they've been following the same strategy that they used to force the pull out of the Soviets. Some tactics have been modernized and adapted to the US, but they've all been intended to suck us into asymmetrical warfare near their strongholds - in our case, they managed to suck us into urban warfare, with some mountain fighting, as opposed to primarily mountain fighting in their previous war.

If all you're saying though, is that they don't dismiss any tactics a priori as absolutely immoral, well, neither do we or does anyone else. That's a trivial fact of modern warfare - anything goes if you can get away with it.

AnonymousMarch 15, 2007 4:01 PM


seems to me you are stereotyping young, middle eastern terrorists. There are more than just one "they".

David ThomasMarch 15, 2007 5:27 PM

With a system like this, there will never again be another attack like 9/11. No longer must the terrorists throw away their lives when they turn our planes into missiles, killing thousands. Thank you, Homeland Security, for this bold step forward.

RealistMarch 15, 2007 6:54 PM

"It constantly amazes me that we have a single issue into which every elected official is willing to pour unlimited amounts of money, yet nobody is actually applying the slightest amount of thinking to the issue. How does that happen?"

Because it is easier for the politicians, and their friends, to continue the FUD and get funding for their pet projects (and friends) rather than address the real issues of foriegn policies and how they mis-treat other nations / peoples. No one votes for the pollitician that says his country is mistreating others, but they will vote for the politician that spews FUD while getting more monies into the local coffers.

quincunxMarch 15, 2007 6:57 PM

9/11s will occur whenever the federal government wants to commit them AGAIN.

Anonymous PilotMarch 15, 2007 8:01 PM

If the system is intended to be self contained what's it going to do sqawk 7700 and attempt peform an autoland at some random runway.

Wrong. 7700 is for *general emergency*. 7500 is for hijack, and 7600 is for NORDO(loss of radio)

JimMarch 15, 2007 8:30 PM

Using Wikipedia, Technion researchers have developed a way to give computers knowledge of the world to help them “think smarter,��? making common sense and broad-based connections between topics just as the human mind does. The new method will help computers filter e-mail spam, perform Web searches and even conduct intelligence gathering at more sophisticated levels than current programs. See

Wikipedia computers will be able to sort out intel better than people. There are more microprocessors than terrorists. Wikipedia needs automated so it can delete bad information when it gets posted or before it goes live.

skyfireMarch 16, 2007 12:19 AM

Having had to deal with an autopilot failure, this is a really, really bad idea.

jeremydMarch 16, 2007 5:57 AM

I blogged this too because it's such an obvious marketing ploy. I wrote instead that it ALLOWS another 9/11. It's so stupid to think that then can add remote controls and prevent someone else from blocking/hijacking the signal.

AleMarch 16, 2007 8:05 AM


Seems your preconceptions defined too much your interpretation. I do not think that 9/11 generated any set of new rules; that is not my point at all. My point is that "the rules" is just a cognitive band-aid. I meant my post to convey that, in game theoretic terms, the strategy set of the players changes with time. You interpreted my post to mean that I expected new rules to be defined by specific events. So, just to clarify: No, thre are no predictable rules.

In chess, however, there are. You can castle. Rooks move in some way, knights in another, and so on. And you can expect that to carry on throughout the game. The true strategis can be very complicated though... and therein lies the beauty of chess.

Usually, humans are much more unpredictable than a rook or a pawn, and their collective dynamic correspondingly unpredictable.

And of course, once you misunderstood the first bit, misunderstanding the rest followed:

"If you at least consider the possibilities, though, you might have a chance at preventing an attack rather than having to say "Who would have thought..." in retrospect."

The set of possibilities is too big to be exhausted. It is pointless to try to do so. If you design generic enough countermeasures, the specifics of the threat are less important, and the necessity of predicting every possible movie plot evaporates.

Anonymous PilotMarch 16, 2007 12:20 PM

Here is a nice attack on such a system. First, activate the autopilot system by hitting the cockpit door. Then, drive a truck filled with Ammonium Nitrate and fuel oil next to the ground station. Detonate. The whole world sees a plane that *nobody* can control flying until it runs out of fuel and crashes.

ArchonMarch 16, 2007 1:07 PM

While perhaps not relevant, I remember a few years before 9/11, the TV show "Martial Law" ended with a two parter involving planes being hijacked and crashed into NYC (no specific target). (Spike TV or TNN or whatever it was called started quietly dumping episodes like mad after that, including a bioterror plot post-anthrax-letters.)

While there were obvious differences in the plot and the baddies - their motivations were far more movie-plot style, for instance - I'm suddenly reminded of one specific difference. In Martial Law, the planes were remote-controlled.

C GomezMarch 16, 2007 1:09 PM

I think you find in the rest of American society (can't speak for other societies), you find people reduce risk in the same fashion. Almost everything is dealt with in a reactive fashion without thinking about the larger picture.

It happens in office culture, families, schools. People just want to think the same thing can't happen again without thinking of the overall risk picture.

MMarch 16, 2007 2:28 PM

If folks really want a counter-terrorism solution like this "autopilot", then why not put a parachute recovery system on airplanes?

Economically it makes little sense. But technologically it's feasible.

Jim HyslopMarch 16, 2007 3:04 PM

When I clicked on the link to the headline, all I got was a message saying "Account for domain has been suspended." Is the article available on any other site?

Jim HyslopMarch 16, 2007 4:11 PM

Silly me - I forgot that "Google is your friend!" I found the article.

@Anonymous pilot - what makes you think nobody can control the plane? The article (well, at least the article I found - explicitly states that it can be controlled from the ground.

In addition to the pilots' concerns above about system failure, I'd be concerned about the system getting triggered accidentally. The trigger that detects force against the door would have to be able to distinguish between, for example, heavy turbulence and an attack.

Or suppose some authorized person is entering the cockpit, and the latch mechanism sticks when they turn the handle (or whatever you do to enter the cockpit). Would the sensors be able to distinguish between clumsiness and an attack?.

And another thing - the device has been secretly patented by Boeing. One of the first things I learned from Dr. Schneier is to be suspicious about anyone who declines to reveal their algorithm. Do I detect a whiff of snake oil?

X the UnknownMarch 19, 2007 1:04 PM

@Matthew Skala: "What we need is for cartoonists to predict all the OTHER stupid security ideas people will try, so that we can have them ready when they get proposed in earnest."

Of course, it didn't help that "Terry and the Pirates" predicted the Pearl Harbor attack...which turned out not to be so stupid a prediction, in retrospect.

Ron SiegelApril 24, 2010 2:48 AM

I have even sent this one to the President after 9/11, with no reply at all.

To prevent this type of attach from ever happening agian, the following must be done.

1. No intenal door to the cockpit, Pilots will have there own External Door.

2. If the are alerted from the Passenger Compartment Through Coms that the plane is being taking over or eveyone will die, then the press a button turning off the Coms to the passenger compartment.

3. the Next is a must. Now the only job the pilots have is to get the plane on the ground.

if these steps were in place then all the terrorist would have done was get 4 planes to land.

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