Aircraft Locator a "Terrorist's Dream"

The movie plots keep coming and coming. Here’s my nomination for dumb movie plot of this week:

Skies ‘now terrorist’s dream’

Australia’s proposed new aviation tracking system would make it easier for terrorists to locate aircraft, aviation campaigner Dick Smith said today.

Mr Smith said a plan by Airservices Australia to replace radar tracking of planes with the Automatic Dependent Surveillance Broadcast (ADS ­ B) system would allow terrorists to track every aircraft in the sky.

“Government policy using conventional radar makes it almost impossible for a terrorist or a criminal to locate the position and identity of an aircraft,” Mr Smith said.

“With ADS ­ B it’s the opposite because all you need to track every aircraft is a small, non-directional aerial, worth $5.”

Under the present system, a terrorist can locate the position of an aircraft by looking up. And if a terrorist is smart enough to perform this intelligence-gathering exercise near an airport, he can locate the position of aircraft that are low to the ground, and easier to shoot at with missiles. Why are we worrying about telling terrorists where all the high-altitude hard-to-hit planes are?

Now I can invent a movie plot that has the terrorists needing to shoot down a particular plane because this or that famous personage is on it, but that’s a bit much.

Posted on May 29, 2006 at 12:00 PM52 Comments


Tom May 29, 2006 1:19 PM

If the terrorist is near an airport, he can locate the position of aircraft that are low to the ground with his eyes.

Dom De Vitto May 29, 2006 1:33 PM

I’m sure Air force one will be fitted with one, if it’s Austrailian law 🙂

Even if you’re not near an airport, and can’t see the target, commercial aircraft follow VERY repeatable routes, which pretty much only vary due to wind, and ATC intervention. Even these variations can be deteted with any (pilots-grade) weather chart and a radio.

Next we’ll be hearing about cruise liners being a terrorist dream because they don’t carry depth charges and are also a sitting duck for any kind of air attack.

Anonymous May 29, 2006 1:33 PM

Clearly we cannot allow terrorists (or, by extension, anyone else) to possess eyes.

Longwalker May 29, 2006 1:42 PM

Would it be cynical to ask if the cost to airlines to install ADSB transponders might have something to do with why this guy doesn’t like the system?

Always follow the money.

George Hotelling May 29, 2006 1:49 PM

Grocery stores ‘now terrorist’s dream’

Australia’s proposed new food selling system would make it easier for terrorists to locate food, interest-conflicted campaigner Dick Smith said today.

Mr Smith said a plan by Foodservices Australia to replace hunting and gathering with the Uniting And Strengthening Australia’s Produce Aisles Through Retail Interchange Of Terror-money (ADS B) system would allow terrorists to exchange money for food.

Dan Lewis May 29, 2006 2:23 PM

The real danger is that the terrorists will be able to set up 5 dollar antennae at all major airports, and feed the traffic to data mining programs that determine which planes are carrying especially virulent biological weapons for the CDC.

Then the terrorists hijack such a plane and threaten to let loose the virii. Then Nicolas Cage and Sean Connery infiltrate the plane and save the day. It’s “The Rock 2: Plagues on a Plane”.

davep May 29, 2006 2:29 PM

@ longwalker

If Dick Smith was following the money, he would be encouraging this system. I am assuming this Dick Smith is the same Dick Smith who founded Australasia’s largest chain of hobby electronics stores (and is also a well know aviation enthusiast and adventurer.) If Dick was ‘following the money’, this system will lead to queues of terrorists in his stores buying small non-directional antennas, and a few dollars more worth of kit to decipher the signal.

Dirk Smythe May 29, 2006 3:14 PM

And in case the terrorists aren’t looking up, many roads near airports have traffic signs that say “Low-Flying Aircraft”, so drivers don’t freak out when a 747 flies across the road at only a few hundred feet.

Clearly, terrorists driving cars around our road systems, desperately seeking an airport to attack, will exploit these road signs at every opportunity. Therefore, I propose that we remove all such road signs, and all other ones like “Stop” or “Yield”, just in case the terrorists don’t have the IQ of a tree stump, and the observing powers of 3-year-old child.

Come to think of it, we should ban children, too, because some of them will grow up to be terrorists, and it’s better to remove every conceivable future hazard than to consider costs, risks, rewards, or any of that intellectual clap-trap.

Michael Ash May 29, 2006 3:29 PM

@Stu Savory

Yamamoto managed to involve the most powerful nation in the world in a personal vendetta against him. If modern terrorists had a bunch of high-tech fighters and a huge logistical support base for them, the way Rex Barber and the rest had, then we would be justified in keeping these things secret. But terrorists don’t have these things, and so they can only bring down an airplane by either being present on it, or by being near an airport where it is operating, and so those are the threats that we should worry about.

Locator May 29, 2006 3:30 PM

I haven’t researched ADS B, but the question that comes to mind is if this would make it easier to create an inexpensive “homing missle” that would follow an ADS B signal directly to a particular aircraft (or really any aircraft emminating this signal), regardless of altitude or location.

Certainly, aircraft currently emminate other trackable signals, like transponder codes, but I would expect one would have to have more sophisticated (and expensive) radar equipment to detect and pinpoint a particular airplanes signal from their transponder code. Even harder to build a homing missile that could track a particular plane accurately.

Ok, here’s the movie plot…
One doesn’t need expensive, hard to acquire Stinger type missiles to take down an airplane, just get a lot (hundreds, or thousands) of small-medium size type model rockets, add an inexpensive ADS B tracking device and send them off (small explosives optional). Impact alone from a few of these model rockets could be enough to cause enough damage for the plane to crash.

Ed Hurst May 29, 2006 3:38 PM

In some locations, it doesn’t even require a missile. Our neighborhood Air Force base features clear line of sight to the entire runway at both ends. I could in theory crash an aircraft on take-off with a few carefully aimed bullets into each intake.

Michael Ash May 29, 2006 3:59 PM

@ Locator

Building a model rocket that can reach 30,000 feet, much less one which can track an aircraft moving at 600mph accurately enough to impact it, is vastly more difficult than you make it sound. And even if such a thing were accomplished, you almost certainly wouldn’t bring the airplane down. Airliners are more fragile than other popular types of transport, but they’re still pretty robust compared to the sort of damage that would cause.

David Cantrell May 29, 2006 4:04 PM

Now I can invent a movie plot that has the terrorists needing to shoot down a particular plane because this or that famous personage is on it, but that’s a bit much.

Already been done I’m afraid. Chap with missile waiting near end of runway, another a couple of miles away on a hill with binoculars phoning him when the plane with the right registration flies past.

geoff lane May 29, 2006 4:08 PM

Don’t commercial airliners carry IFF transponders any more?

Many years ago I spent months writing part of an IFF simulation for a radar test setup.

Alan Porter May 29, 2006 4:40 PM

A few weeks ago, I got to ride in a small 4-seater plane that was demonstrating the ADS-B system. The display looked a lot like what air traffic controllers see… it shows planes in the area, labelled with their tail numbers and altitudes.

The information that is shown on ADS-B is a real-time compilation of [A] the plane’s tranceiver which (optionally) broadcasts its position, [B] air traffic control (which does know your tail number in controlled airspace [C] transponder “squawk” codes.

To get an idea of what it looks like, see Enter an Airport ID code (like ORD for Chicago) and then click on the map at the top. You’ll get a new window showing all traffic in the area with airplane identifiers.

This seems a lot like what we’re seeing on British highways.

The main terrorist threat is not that someone can aim a missile at a random plane. It’s that they can target a SPECIFIC plane.

Pick a celebrity or politician, find out their airplane tail number from the FAA’s aircraft registry, then watch your ADS-B display to tell exactly (within about 6 seconds) where that plane is.

Filias Cupio May 29, 2006 5:15 PM

“The main terrorist threat is not that someone can aim a missile at a random plane. It’s that they can target a SPECIFIC plane.”

They can already. Just hang around the departure or destination airport listening to air traffic control. The new system may make it easier to attack the plane in cruise, but a terrorist wouldn’t want to when takeoff/landing are so much easier than cruise in so many ways.

D May 29, 2006 5:49 PM

Wait, wait, wait…

Don’t modern commercial aircraft already have a transponder that announces “This is who I am, and this is my location”? Even if it doesn’t announce its own location, the North American tracking system knows where the signal is coming from.

Further, isn’t this also why we “lost” one of the flights on 9/11? The terrorists turned off the transponder and radar was apparently useless.

Point: we already use this … at least in the states. Am I wrong?

Michael May 29, 2006 6:00 PM

Even IF there is an important person on board I would still bet they try to get it during landing / take off, simply a lot higher chance for a fatal kill.

Having said that: Planes don’t just fly villy nilly around, they follow pre-determined rountes and you can buy those maps in book stores (or at least you could), so you don’t need any fancy finding tool to begin with.

I love paranoia.

BOB!! May 29, 2006 6:27 PM

@Alan Porter

There is no increased terrorist threat that they can target a specific plane. No ‘celebrity or politician’ is so beloved or so important that taking them out would score more of a victory for a terrorist than taking out any commercial jet.

Also, in order to take out a specific aircraft, they need the capability to take out an aircraft, period. Since no terrorist group has managed to do this in the US since late 2001, and it would clearly be a desirable action for them, I assess that this means that no terrorist group has the capability to take out an aircraft in the US right now.

Unixronin May 29, 2006 7:18 PM

Actually …. don’t blame Yamamoto. He warned the Japanese government all along that going tow ar with the US was a bad idea. Yes, he came up with the plan for the Pearl Harbor attack, because he figured that Japan’s only chance to win was with a single, decisive, crippling stroke before America could mobilize, and he warned that the consequences if it went wrong would be terrible. He was right, even though what went wrong was diplomatic, not military.

It was Yamamoto who told the war planners, in response to plans for an amphibious invasion of the West Coast, “You cannot invade the mainland United States. There would be a rifle behind every blade of grass.”

I think Admiral Isoroku Yamamoto and Captain Hans Langsdorff would have understood each other very well. They were alike in many ways.

Sparohok May 29, 2006 7:41 PM


Aviation transponders communicate directly with air traffic control radar systems. It would be difficult to get any useful information passively. The terrorist would need to transmit as well as receive, and they would need quite sophisticated electronics. Dick Smith is probably correct that it would be “almost impossible” for a terrorist to exploit the current transponders.

scot May 29, 2006 9:07 PM

Dick Smith doesn’t own Dick Smith Electronics now for probably 20 years. He’s also known as a interfering busybody who has previously managed to piss off the commerical pilots with mismanaged bureaucracies headed by himself. In other words, he is a discredited blowhard.

Paul May 29, 2006 10:17 PM

“Australia’s proposed new zoo would make it easier for terrorists to place snakes on aircraft, aviation campaigner Dick Smith said today.”

Old World Blue Eye May 30, 2006 2:33 AM

Target: Person

Why would terrorists shoot down plane to get some person killed?

Target: Biological stuff

Yeah, this might have some idea. Just be sure that containers will burst also in air to spread stuff around.

wkwillis May 30, 2006 3:21 AM

Ed Hurst
If you fired into the intakes of an aircraft on takeoff, you would have to be standing roughly in front of the plane, and since they take off fueled, you would be in the impact zone of a considerable quantity of jet fuel.
I do not recommend this.

Kai Thomsen May 30, 2006 6:28 AM

Even today it is very easy to track commercial aircraft through their transponder signals. Mode-S transponders send altitude, a four-digit code, the aircraft’s callsign and type. You can even buy commercial software for a PC to display these data. That way you will almost see as much as the air-traffic controllers themselves.

Alex May 30, 2006 7:00 AM

They already have transponders, and I can buy a so-called virtual radar (that translates Mode B SSRs in range into a radar-like PPI on a computer) just yards from this office.

And Dick Smith is a certified wanker.

Steven Brown May 30, 2006 6:41 PM

We better do something about rail tracks then…

I actually had a similar discussion with a mate over emergency vehicles. I suggested they could transmit a GPS signal so that other motorists have plenty of warning that they are coming. He argued that this would make it easier for someone to disrupt the emergency services. My argument was that any attacker can hear the sirens, see the vehicle, and predict a route given that most emergency vehicles are going to or coming from a base station.

Jake Brodsky May 30, 2006 9:35 PM

Folks, this is silly. This is more “fear those evil flying machine” nonsense. You want to know where an aircraft is? See

Yes, every aircraft that flies near a major city (one with Class B airspace) already has a transponder with an altitude encoder. ADS-B was meant for rural areas without Radar coverage and TIS broadcasts for those with Mode S transponders. It’s all the rage in Alaskan airspace. They love it.

In any case, we already know where the aircraft are and where they’re going. It is done for reasons of safety –not security. Would you prefer that I NOT know where other aircraft are in those clouds? Bruce, I’m glad you’re thinking “movie.” There is no reality to be found here…

Longwalker May 31, 2006 12:19 AM

Someone ought to tell this guy that SAM systems large enough to hit an airliner at cruise come with their own radars and are, indeed, rather useless without them. If a bunch of terrorists have a SA-12- or SA-17-class SAM unit capable of hitting an airliner, they don’t need ADSB for target aquisition.

The notion of homebrewing a high altitude SAM with an ‘ADSB seeker’ is just laughable. Terrorists with the skills to build missiles aren’t going to waste their time shooting down aircraft: surface to surface missiles are easier and far more lethal.

Tank May 31, 2006 5:06 AM

“I haven’t researched ADS B, but the question that comes to mind is if this
would make it easier to create an inexpensive “homing missle” ”

When I read this the question that comes to mind is do you believe someone has created an inexpensive non-homing SAM capable of 10s of thousands of feet of sustained accurate flight complete with guidance, navigation and warhead that is simply missing a way to find a target ?

This is an Australian-only system.
You want to know something that’s inexpensive in Australia ? A brick. You can exen acquire them for free from building sites. If you’re so inclined you take said brick to the Prime Minister’s house and chuck it at him while he goes on his morning walk.

So terrorist subject “B” has assassinated the non-token head of state with a piece of masonry. For arguement’s sake let’s say this cost him a bus ticket and 2 hours travel time.

Terrorist subject “A” meanwhile is fking about with some amatuer pyrotechnics in an attempt to intercept something else travelling at a few hundred miles an hour at 10s of thousands of feet. On a budget.

Good luck to him. There are actually a certain number of terrorists in south east asia and Australia. If one of them is fking about with high explosives and rocket scientist math which realistically poses no threat to anyone but himself I say go for gold son.

Fred Page May 31, 2006 11:37 AM

“Why are we worrying about telling terrorists where all the high-altitude hard-to-hit planes are?”
-Because this system also helps with low-altitude planes; specifically it reduces neck strain, which as everyone knows, is a chronic problem for most terrorists 🙂

jh May 31, 2006 11:43 AM

Merchant shipping has an automated “black box” on every vessel over a certain size that is used for collision avoidance and location tracking. It’s under the auspices of the International Maritime Organization and is somewhat blandly called AIS (Automated Information System).

What’s interesting is that some vessel captains will switch the system off when in known piracy areas to avoid possible exploitation by bad guys.

Pat Cahalan May 31, 2006 1:00 PM

@ Brandon

Can you legally own a radar station?

You mean, can you legally operate a device capable of radar tracking? Sure. If you own your own jet plane, you have your own radar station, and it’s mobile! Whoo!

The licensed/restricted bands in the EM spectrum and the laws concerning them are incredibly complex, but if you ever want to burn a couple of months or so everything you ever wanted to know about radio frequency laws (in the US anyway) is publicly available on the FCC website.

Jim Hyslop May 31, 2006 3:29 PM


I could be wrong, but I believe that in the current system, the transponder code is assigned upon checkin with ATC. So a particular aircraft will not always be assigned the same transponder code. ‘Course, all you have to do is monitor the ATC frequencies, and listen for the transponder code that ATC assigns.

elamb May 31, 2006 7:45 PM

I think that we should copy the Isreal’s security. They seem to be so much smarter. They’ve had years of practice.

Jungsonn June 1, 2006 5:58 AM

As a little boy (7 or 8) i had also an idea which is close to it. I thought about thieves who rob a bank, and i figured if they could build a small tracking device (costs are low) and plant them on all the cars of the local police, they could track them and know when they are in the area.

But yeah that was in the days there where no cell phones and other high tech stuff. But to me then, it seemed a perfect plan. Thought out from the idea of thinking up althernative ways, and my interest in electronics.

yay! 🙂

Anonymous June 2, 2006 7:58 AM

Security issues aside, I hope they’re not planning on replacing conventional radar with transponders. They could augment the current system; that would be fine. But for the sake of safety — not security against malice, but plain old accidental failure — ASSUMING that every aircraft has a functional transponder is just plain stupid.

The passive system only has one source of failure, the transponder system has two (really, both have many more factors, but there’s an increase in complexity, and the simplest model says a conversation requires two parties, while passive observation requires one). An airplane doesn’t suddenly become invisible to radar if one subsystem malfunctions.

Bluefin June 15, 2006 5:05 AM

All the comments here seem to be about terrorists identifying specific aircraft. But my immediate thought about this was whether terrorists/blackmailers could now buy a whole bunch of ADS-B devices, tweak the electronics somehow and flood the ATS with bogus aircraft leading to “air traffic chaos”.
I have no particular knowledge or expertise in this field, so I’m hoping someone’s going to tell me that this just won’t work.

Dan June 16, 2006 3:17 PM

Last I checked, the terrorists did not have the capability to shoot down a commercial airliner at cruising altitude. It would be far simpler, as you point out, to attack the aircraft when they are far more vulnerable, in the takeoff or landing flight paths.

The flight paths of most major airports are well-known and easily observable. At some major airports, the flight paths go over heavily populated areas, where the terrorists would be able to easily blend in and hide.

Too many people worry about what capabilities the terrorists might have, rather than the ones that they already possess. Most commercial aircraft would not even require anti-aircraft equipment to down—a large caliber rifle would probably be sufficient in many cases.

True security is only achieved if you can define the problems properly. Worrying about who can hit an aircraft at cruising altitude is not a realistic concern, given what we know about the terrorists current capabilities.

Airnav follower July 26, 2006 6:08 AM

Dick really killed off an Aussie industry success story, so much for the poor blokes who were going to build and fit the gear in Australia. The new radars will do SFA to enhance outback coverage at any altitude, cost tens of millions and not even improve detection efficiency around the centers where they will be fitted. A sensible and cost effective terrorist would only consider striking a plane on take off or landing, ADSB data at high altitude means nothing to him.
Thanks Dick-h….
Who in the system got a handout for this decision ?

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