ADS-B ... Terrorist's Dream, Security's Nightmare (original) (raw)

Automatic Dependent Surveillance - Broadcast

Will ADS-B Increase Safety and Security for Aviation?

(other contrasting opinions on ADS-B may be foundhere)

These five stories are set slightly in the future, but only slightly. Perhaps five years from now. The technology described is an accurate portrayal of ATC systems of today, or in the case of ADS-B, an accurate portrayal of systems that are test flying today. The individuals and situations are fictional of course.

Scenario One....Terrorism

A lone mideast terrorist comes to the United States and purchases (or rents or steals) a light aircraft such as a Cessna 172 or Beech Bonanza or Piper Arrow. While selecting his plane, he is looking for just one item: ADS-B collision avoidance equipment. He knows that ADS-B, installed on all airliners and some business and pleasure aircraft, automatically reports the precise position of the aircraft and also the identity of the aircraft, twice per second.

He has no particular target, his only desire is to cause as much fear and destruction and death to The Great Satan as possible. Having waited for a day of poor visibility, he completes his prayers. Then he flies at low altitude and slow speed above the busy highway toward a major airport. He knows that Air Traffic Control radar will not see him because he has disabled his transponder output, thereby assuring that there will be no secondary returns nor any ADS-B transmissions. His aircraft is smaller than the tractor-trailers on the highway below, and the ATC primary radar has been programmed to eliminate highway clutter from the display. He will not be seen.

The terrorist also knows that the interval when a large aircraft is most vulnerable is on final approach. It is moving slowly at low altitude, flaps and slats and gear are extended and engines spooled down, this is the point in the flight when the plane is least maneuverable. Using the ADS-B readout to spot his target, he flies up the glideslope and directly toward the doomed airliner.

Until the last moment he cannot see the oncoming plane but he knows it is there. The display on his ADS-B is showing its altitude and position with an accuracy of a few meters. The airline crew, monitoring their instruments and complying with pre-landing checklists, never sees him at all. At the last instant he shouts “Allah Akbar” as he flies thru the windshield of the larger aircraft, taking hundreds of people to their death.

Scenario Two....Extortion

I’ll call him Joe. He is not mentally disturbed, at least not any more disturbed than the average guy in this hurried-up society. His intelligence is above par, it's just that he doesn't have any ethical constraints. Joe might have become a successful bank robber or con artist. But Joe is a loner and has long understood that the cops can't infiltrate a group of one. Plus, he'd rather have 100% of the take than to split it with guys who might get drunk and tell the whole story to some hooker. Joe is sharp on computers and enjoys playing with model airplanes, and would rather be tinkering with technology than shooting pool at the neighborhood bar.

In the vernacular, Joe is a geek.

One day Joe reads an article about ADS-B. It tells how the planes are precisely reporting their 3D position, in the clear on 1090 MHz, twice per second. And here's the best part: the identification of the specific aircraft is included along with the position. Suddenly he envisions the whole plan. Extortion! A million dollar bank robbery would be impossible for one man, but a million dollars is pocket change to the airlines. He flips a coin and decides that UAL is his target.

The question is, should he ask for the money first and only destroy an airliner if his demands are refused? Or should he begin by dropping one flight unannounced? The former requires credibility, he will have to reveal how he is going to carry out the threat if his demands are not met. This means he will have to disclose some of his ideas and perhaps provide a photograph of his weapon. Worse yet, it requires more than one exchange of information with the airline. After the first letter, the FBI and everyone else will be scurrying to find him. Best to keep the exchanges to a minimum.

The latter choice, destroying one plane first to demonstrate his capability, seems more foolproof. He can do that before anyone knows what is going on. Then, if the airline balks on payment, he can threaten to publicize the reason the plane went down and drive their customers away overnight. United might fear the publicity as much as they would fear another crash.

Joe goes to work. He builds a model plane, a large one. He has already attended model meets where 1/4 scale planes were flown, he knows that some models weigh nearly as much as a real airplane. Joe's plane will only have one flight, it need not be pretty nor fast nor powerful, its sole purpose is to precisely meet an airliner on final approach while carrying a gallon of gasoline to explode inside the airliner cockpit when the planes collide head on.

He doesn't have access to ADS-B equipment, but that doesn't matter. It's a simple task to put a 100GPSreceiverfromWalMartinthemodelplane,coupledtoareadilyavailablewirelessLANcard.Withasimilarcardinhislaptop,hecanmonitorpreciselywherehisaircraftis.Joedoesn′thavealotoftestequipmenteither,anditmightbetimeconsumingtobuilda1090MHzADS−Breceiverfromscratch.Instead,hesimplytakesthereceiverfromaDBSsatellitesystemhepurchasedatthediscountstorefor100 GPS receiver from WalMart in the model plane, coupled to a readily available wireless LAN card. With a similar card in his laptop, he can monitor precisely where his aircraft is. Joe doesn't have a lot of test equipment either, and it might be time consuming to build a 1090 MHz ADS-B receiver from scratch. Instead, he simply takes the receiver from a DBS satellite system he purchased at the discount store for 100GPSreceiverfromWalMartinthemodelplane,coupledtoareadilyavailablewirelessLANcard.Withasimilarcardinhislaptop,hecanmonitorpreciselywherehisaircraftis.Joedoesn′thavealotoftestequipmenteither,anditmightbetimeconsumingtobuilda1090MHzADS−Breceiverfromscratch.Instead,hesimplytakesthereceiverfromaDBSsatellitesystemhepurchasedatthediscountstorefor199 cash. That receiver, half the size of a deck of cards, tunes from 950 to 1450 MHz which is precisely what he requires. All Joe needs to do is write a little software, and voila, he can monitor the exact position and identification of every airliner within 20 or 30 miles.

At this point, Joe has been able to do the entire job single-handedly with information and materials that are readily available and 100% legal. While finishing construction of the plane, he spends a few days listening to the tower and watching the ADS-B data on his computer. Soon he has a good list of United Airlines ADS-B ID tags. He is ready to go, and no other person on earth has any idea what is about to happen.

Scenario Three....Revenge

Thomas Whitten, Ph.D., is a brilliant scientist. He served honorably in the Army during VietNam, finished his education soon after, and has been working for a major pharmaceutical firm ever since. His career reached its peak when he developed the latest miracle drug which will ease suffering and save untold lives worldwide.

“I was a loyal employee” Tom said. “Many of my colleagues jumped from one firm to another, always at an increase in pay. I didn't. I stayed here year after year, decade fading into decade, because I truly believed in what I was doing. For the past 17 years I have been working on a single project, trying to unravel the relationship between DNA and this particular disease. It was rewarding when we made progress, it was discouraging when we didn't, and altogether too much time was wasted cajoling management to fund our work. Several times the project was almost canceled, and each time I managed to convince the executives that we should continue.

“And look at the company now. We were the stars of the latest mega-merger, the largest ever in the pharmaceutical arena. Our stockholders made billions, literally billions, because of my work. The CEO himself received a $14 Million bonus, other top management guys received millions more.

“And me? What do they give me? A nice little write-up in the company newsletter, that's what I got. I'm making $94k a year, and when I retire next year I’ll drop to 60% of that. Don't those bastards understand who produced the drug that created all the wealth? Yes, I think they understand. I think they just don't give a damn.”

That was all Dr. Whitten said aloud. But the longer he thought, the angrier he got.

It ate and ate at him, eventually reaching the point where he couldn't take it any longer. He briefly contemplated rigging a virus release in the laboratory but that didn't make sense. His fellow workers weren't the problem and he wouldn't do anything to harm them. Management was the problem and they didn't work in the laboratory, they divided their time between the head office in New York and company facilities scattered across the globe. They spent their time flitting from place to place on one of the company jets rather than working...........wait a minute - that's it. The company aircraft! Planes carry top executives. And planes crash.

He established several guidelines. First, his plan must not put him in physical danger. Second, to the greatest extent possible it must not put innocent parties in danger. Third, it must be repeatable because it may take several crashes to achieve the objective. That ruled out trying to plant a bomb on a company aircraft. He might get by with it once - or he might get caught or be blown up in the attempt - and in any event he couldn't manage it repeatedly. Bombs were out, he had to find another way.

If there was one thing Tom Whitten knew how to do, it was research. He had no aviation knowledge beyond a lot of coach class business trips and a handful of trips in company jets, plus the little he remembered from his military days. He had no specific knowledge of how to cause a plane to crash but he had faith it could be done.

So he went to work. He combed aviation journals at the university. He combed the internet. He kept meticulous notes. Under an assumed name he called various aircraft and avionics manufacturers and interviewed engineers about system specifics. He talked with FAA maintenance personnel too. All the information was there, in the open. It wasn't classified, it wasn't trade secret, it wasn't even company confidential. He asked how a plane was navigated, how it interfaced with Air Traffic Control. He learned what the crew did and what systems they depended on for guidance. He learned what portion of the flight was most hazardous and vulnerable. He studied the localizer and glide slope and marker beacons and DME and GPS and all the rest. He bought a Radio Shack airband radio and became familiar with communications jargon. Eventually Tom found the RTCA documents that contain the standards each navigation system must meet. Every tiny detail was openly available.

And he learned about ADS-B. When Dr. Whitten located RTCA DO-242 he knew he had found the mother lode. This was the key to the whole plan. He wanted to destroy specific aircraft while causing no harm to others. ADS-B reports the precise location of the aircraft, in 3D coordinates, and simultaneously reports the identity of the aircraft. That was exactly what his plan had been missing, the means to target a specific plane, and ADS-B provided it.

Outsiders imagine that lab researchers spend their days stirring test tubes and peering into microscopes. Once upon a time that was an accurate picture, but electronics is the dominant force today. Tom was skilled in designing instrumentation to solve fresh problems. Now he turned this talent to his new field of interest.

In ADS-B, every plane has a unique 24 bit identifier which remains with the aircraft. In fact, there is an algorithm to convert tail number to ADS-B identification number. It was a simple matter, with binoculars, to get the “N” number of the company jets when they came to town. Dr. Whitten then hand-processed the algorithm and learned the 24 bit ID code of each plane. Now he could receive the 1090 MHz frequency and know which plane was which.

His plan was simple. On an instrument landing the plane is following electronic signals. The localizer gives left/right guidance, the glide slope provides up/down information. The former is on VHF, the latter UHF, with the frequencies openly available on aircraft approach charts and other documents. The signals are not encrypted, they aren't even digital. The ILS signal, like most of aviation technology, was established near the end of World War II and long before the invention of the transistor or integrated circuit. Some systems (such as the ancient amplitude modulation used for voice communications) date back far earlier. Aviation is unlike other fields of endeavor because the people who develop the technology are not the people who use the technology. And a third group who are neither skilled in the technology - nor skilled in the use thereof - are the ones who make the decisions. Through the years a lot of wacky decisions have been made. In the case of ILS, the radio carrier is amplitude modulated by two tones, 90 and 150 Hz, which are equal amplitude if the plane is centered on the beam. If a particular aircraft receives a false signal it will follow a false path.

Traditionally the marker beacons, all on 75 MHz, give the pilot an indication when he is nearing the airport but do not allow any sort of readout to the touchdown point, so Tom could ignore them. Often the pilot monitors his Distance Measuring Equipment, DME, to determine his distance to touchdown. Tom reasoned that it would be easiest to simply jam the DME frequency for the critical few seconds. Likewise with GPS, once he had identified his particular aircraft he would jam the very weak Global Positioning Satellite signals on 1575 MHz.

None of this was particularly difficult for an experienced researcher such as Dr. Whitten. Indeed, a kid with an interest in ham radio could do as much. But Tom had access to decades of obsolete instrumentation from which he could scrounge the necessary bits and pieces. The ultimate irony, he could use company material to accomplish the objective.

It was easy to phase lock the ILS spoofing transmitters to the real ILS signal, from a van parked a mile or so from the airport and under the final approach. He used directional antennas that beamed his signals upwards to the particular flight while anyone else on the approach would receive the proper ILS signal. Phase locking his signals to the actual ILS would assure that there would be no flag or indication when the target aircraft transitioned from the correct signal to the spoof. Sure, it took some effort, but the specifications were all available so it was far easier than other projects he had accomplished.

The weather was miserable the night of the first crash. Most flights were landing successfully, but missed approaches weren't uncommon. Some planes were experiencing airframe ice, winds were gusty and unpredictable, the rain was heavy at times, and ATC had traffic backed up halfway to Cleveland. The company Gulfstream IV was making what appeared to be a normal approach when it began to drift to the right. It descended prematurely about a half mile from the end of the runway, struck an embankment at the outer perimeter road, bounced over two maintenance buildings and a communications shack, hit the ground with its left wing, cartwheeled, and burned. All aboard were killed.

The NTSB accident investigation concentrated on the navigational aids, aircraft systems, ATC actions, and crewmember performance. The ILS checked out perfectly and no other plane had experienced any ILS problems. The aircraft systems checked out OK, at least the parts that could be reconstructed. ATC had made no blunder and there was nothing on the communications or radar recordings to indicate a problem. Predictably, the crash was blamed on pilot error.

But Thomas Whitten, Ph.D., wasn't finished. Several months later, at a different airport, the same pharmaceutical company mysteriously lost another flight.

Scenario Four....Data Mining

One hot new field in the information age is data mining, extracting and refining nuggets of valuable information from the immense field of electronic data that exists all around us. Some data mining is legal, some is illegal, but most is too new and expanding too fast for any legal or ethical framework to develop. The old fashioned concepts of privacy and ownership are being questioned in ways that were unimaginable 20 years ago.

Meet DataMiners, LLC. For a small fee, DataMiners makes it easy for a company to track its fleet of aircraft. Or the fleet of the competitor. For an additional fee, DataMiners will reduce and analyze the information. For instance, the news that the competitor’s bizjet traveled to a specific plant is not particularly useful. But when travel patterns are analyzed and combined with data from other sources, a message emerges that the competitor is having quality problems, or vendor problems, or management problems. Or perhaps the competitor is secretly developing a new product or negotiating a merger. Information like this is quite valuable in the marketplace.

Wouldn't a stock trader have liked to know that the Chrysler and Daimler Benz aircraft were visiting the same destination - on the same days - in the months leading up to their merger? Our securities laws protect the market from_insider_ information, but DataMiners LLC is an outsider and whatever they discover is available to the highest bidder.

Whether it's a mid sized company or a multinational corporation, conducting business in privacy (and thus traveling anonymously) is essential to survival and maintaining the competitive advantage. In an ADS-B world, the company aircraft will be a liability rather than an asset.

The National Business Aircraft Assn, NBAA, has already learned this lesson and has done a complete turnaround from their earlier support of Aircraft Situational Display (ASD). ASD is somewhat similar to ADS-B, it also reports which aircraft is where. But ASD is limited to aircraft operating under Instrument Flight Rules, the data is compiled by the FAA, sensitive data such as military flights is deleted, the position of the aircraft is not sufficiently precise for tactical purposes, and the data is slightly delayed before release by the FAA. (For more on this from NBAA’s perspective, seehttp://www.nbaa.org/digest/1998/11/opsnotes2.htm and http://www.nbaa.org/pr/1998/98-18.htm .

Unlike Aircraft Situational Display, ADS-B comes directly from the aircraft and is freely available to anyone with a 1090 MHz receiver without passing through any agency for filtering or control. ADS-B and efficient use of the corporate fleet are incompatible. If we are promoting aviation for business purposes, we must oppose ADS-B.

Scenario Five....User Fees for General Aviation

Harvey Patton started his company for the best of reasons. His city was about to close the airport and turn the land into an industrial park. The various factions had fought over this issue for years and Harvey realized that if the airport users were seen to be paying their own way, and perhaps paying a bit extra, then the city could be convinced to keep the airport open.

In that light, local airport user fees didn't look so bad. If the fees were structured according to the weight of each aircraft, the bulk of the expense would be borne by the companies that could afford it while the pleasure pilots would only pay a token sum. It sure beat losing the airfield.

So Harvey went to the city with this proposal: He would supply and maintain the equipment at no cost to the city, all the city had to supply was a place to house a PC and antenna. The equipment would receive and log the ADS-B signals and routinely modem the data to Harvey's business where billing and collecting would be done. The city would receive 85% of the monthly billings without lifting a finger to do any work. All aircraft activity would be monitored 24 hours a day, 7 days a week whether the tower or FBO were on duty or not.

The city accepted, and the idea worked. Every month the city received a substantial check which went into the airport fund and provided a surplus. Everyone was happy. Well, the users weren't totally happy but they realized it was better than closing the airport altogether. And many users, the smaller aircraft, were escaping user fees by not installing ADS-B. True, not having the collision avoidance equipment meant a higher risk, but many pilots were more concerned with high costs than improved margins of safety.

Harvey realized that we are losing an airport a day in the United States and some of those are important GA facilities similar to his airport. He went to those cities and sold the same deal, it was easy to do the automatic billing and collections from his location. He was getting 15% of the take from a number of fields and the revenue began to roll in. Next step was to approach the Westchesters and Addisons all over the country with the same arrangement, every airport needs additional funding and this deal was too good for them to resist. Business increased by leaps and bounds (or takeoffs and landings) and Patton Aviation Revenue was a resounding success.

Within a few years Patton equipment was working all over the country. It was installed, it was functioning, it was a proven source of aviation funding. Of course the users were unhappy, particularly at the fields where the fees were set to limit traffic or limit noise or for some other artificial reason. But the corporate users, those who were required to use ADS-B, had no alternative but to pay.

Then the new Congress instituted federal user fees for General Aviation. This hadn't happened previously because there was no billing and collecting infrastructure, but Harvey Patton had changed all that. Or more accurately, ADS-B had changed all that.

The feds contracted with Patton Aviation Revenue in the same way they contract with Jeppesen or Flight Safety or others who provide a service. Patton did the billing and kept a percentage of the take. Suddenly every takeoff, every flight mile, every landing was computer monitored. VFR or IFR, the airspace bill arrived at the end of the month.

The users screamed, they cursed Harvey Patton, but it was no use. If they were going to fly with ADS-B they were going to be billed. Yet the pilots with foresight, those who had never installed ADS-B, weren't paying a cent. Until a court action was filed, that is.

The US Federal Court for the Ninth District ruled that all airspace users must be treated equally. The court left it up to the FAA to determine what “equally” consisted of but the edict was firm, equality in user fees had to be maintained.

What happened then? There are many possible endings to this story. Maybe each non-ADS-B aircraft received an “average” bill every month whether they flew or not. Or maybe every plane was forced to install ADS-B and the resulting frequency overload created the same situation we've had at Oshkosh for many years: “turn your transponder to standby when 30 miles out”. Then the planes, with their ADS-B turned off, were prohibited from flying in controlled airspace. Or maybe the aircraft owners simply gave up and sold the birds for whatever they could get and pleasure flying died, taking FBOs and manufacturers with it.

Today it is not possible to saddle General Aviation with user fees for one simple reason - there is no infrastructure to collect those fees. The test that aviators must apply to ADS-B (or any similar technology) is simple: Are there any words that Congress could say that will hurt us? If the answer to that question is yes, then pilots and aircraft owners must reject the technology.

Proponents of ADS-B tell us that there will be an “anonymous” mode that the pilot can select. But that will be true only as long as the rules permit it. Once upon a time we could turn off the transponder if we wanted to, but as the years passed that choice was eliminated. The same will inevitably be true of an anonymous setting, it can only be used until it is prohibited. First prohibited at flight levels and at major hubs, then prohibited in IFR, then prohibited, period.

Proponents of ADS-B also tell us that we can be tracked today. That is somewhat true, but recent experience in the well publicized JFK Jr. accident is instructive. His plane went down around 9 PM Friday and the search and rescue efforts began at 6 AM Saturday. Those efforts continued, under intense press scrutiny, through all of Saturday, all of Sunday, and all of Monday. Around midday Tuesday the FAA finally decoded enoughof their radar tapes to determine the location where the plane went into the water. After the spot was pointed out, the remains of the aircraft were promptly found.

It took FAA more than 72 hours to find one aircraft, an aircraft that the President of the United States and the world press corps were actively interested in finding. Given the number of flights daily, it is clear that the FAA does not begin to have the resources to track and bill every flight.

Tracking every IFR flight would be somewhat easier, but many of those will switch to VFR if there is a substantial money saving. And if it comes to that, safety will suffer. Isn't safety what ADS-B was for in the first place? Don't you detect something wrong here?

This is Who I Am - This is Where I Am

Automatic Dependent Surveillance - Broadcast, ADS-B, links an unambiguous “This is Who I Am” with a very precise_“This is Where I Am”_. Never before in aviation have we put those two pieces of information together and broadcast them in the open for anyone to receive and use as they see fit. We should not do so now.

Decades of ATC experience have proven that identification of traffic is not something the pilot needs. He or she needs to know where the traffic is, which way it is moving, perhaps its size or its speed, but never its identification number. ADS-B flies in the face of this experience.

ADS-B has not been widely deployed yet. There is still time to stop it. Most airlines have not invested any money in it yet, nor have the government entities nor the general aviation community. I suggest that it is not in the best interest of aviation to deploy ADS-B in its present form. Like AAS, MLS, and other recent systems, its gestation has exceeded its usefulness. ADS-B made a great deal of sense when it was first proposed. But data processing capability is not the same today as it was twenty years ago. We live in a different technological world now, just as we live in a different political environment.

The ADS-B community will laugh off my scenarios. They will explain that identification is necessary in order for aircraft to autonomously interchange information and automatically negotiate evasive techniques. That was true 20 years ago, it is not true today because of the great strides made in computer and DSP technologies. “Not Invented Here” is alive and well in the ADS-B community, these people have devoted major parts of their careers to ADS-B and its understandable that they are unwilling to see their system rejected. Nevertheless, aviation deserves a collision avoidance and traffic management tool that achieves the positive objectives without the serious negatives I have described.

Would Anyone Use a Transponder Reply to Destroy an Aircraft?

AN/PPX-3B

In a word, yes. Litton Guidance & Control Systems makes such equipment and offers it openly on the internet. Read the Litton AN/PPX-3Boverview,FAQ,and specifications. A similar Litton product is their TPI-10, here are links to theoverview,FAQ,and specifications.

If Litton (and their competitors around the world) can do that with a common transponder, think what they can accomplish when ADS-B reports the aircraft's exact identification (not just a squawk code) and simultaneously reports a very precise 3D position!

The potential ADS-B threat is immense.

Why Am I Writing This?

My purpose in writing these scenarios is to illustrate the problems that I perceive. I am not delivering a threat, rather I am delivering the message that ADS-B is a threat. ADS-B is a terrorist's dream and security's worst nightmare. I have previously talked with various people within the FAA, with no success. It seems to be a matter of compartmentalization or jurisdiction. I have talked with those charged with “aviation security”, they see their job as one of gates and fences and bomb-sniffing machines. They are not concerned with anything that happens after the wheels leave the runway. I have talked with ATC and ADS-B systems people, they have no interest beyond air traffic control and airspace utilization. I have spoken personally with FAA Administrators Hinson and Garvey. In essence, the ADS-B security problem falls in an FAA department that hasn't been created yet. In addition, there is a great deal of buck-passing between FAA and ICAO and RTCA and the EU and other participants. No one wants to reject “progress”, and ADS-B inches closer to reality.

Am I Shouting Fire in a Crowded Theatre?

Is my message "shouting fire in a crowded theatre"? No, it is not. I am shouting the grave potential of fire in a theatre that has not yet been built. There is no danger to the public, nor to the republic, from my message. The danger is within ADS-B itself, and my sole intent is to educate the aviation community as to that danger in time to stop the construction of this dangerous system.

My background in this topic comes from a decade of designing, producing and marketing general aviationequipment that receives the 1090 MHz frequency, and as a pilot and aircraft owner with more than 30 years experience. I have learned how easy it is to receive the data, and how much diverse data is available on that frequency. I understand that any data can be used for good or it can be used for evil. And I believe that the systems of tomorrow must be designed with both in mind.

Do we need ADS-B?

Something like ADS-B is necessary as we move into the future. As aviation matures, there are compelling reasons why we must move beyond a manually operated Air Traffic Control. Traffic density is already straining the limits of what a human-centered control system can accomplish. For the forseeable future there will be a human involved when needed, but the routine separation chores can be handled more easily and more efficiently by technology.

So yes, we need an ADS-B sort of system, but without all the negative attributes of ADS-B. Identification is not needed, every databurst will contain a unique identifier within the lat/lon/alt. If two aircraft have the exact same position, they have collided already. Conversely, if they have not collided, by definition they have different positions and thus different and unique identifiers. There is no need for any further ID to permit automated data exchanges between various aircraft.

As we move from an old fashioned manual method of sequencing aircraft toward an automated system we must plan for a larger number of aircraft. ADS-B as presently envioned does not have the capacity for tomorrow, in fact it does not have the capacity for maximum situations today such as the EAA Oshkosh event in Wisconsin every August or the Sun'n Fun event held at Lakeland Florida in April of each year. System capacity is an important matter that has been neglected by the proponents of ADS-B.

One way to maximized capacity is to limit the quantity of information to only that which is needed. This is a further argument against ID, decades of air traffic control experience have shown that the pilot does not need the registration number of his traffic. Maximizing capacity also argues against the concept of reporting at regular time intervals such as once per second or twice per second. The fact is, aircraft do not collide because of time, they collide because of distance (or rather the lack thereof!). It makes sense for an aircraft that is moving at 600 knots to report every second, but makes no sense whatever for an 85 knot aircraft to report that it has managed to travel a few yards since it's last report one second earlier.

A far better idea is for aircraft to report based on distance travelled, such as every 1000 ft. That would provide for six reports per nautical mile while reducing the spectrum usage by a great factor. That same factor would allow for many more aircraft.

Besides providing for traffic densities beyond those we experience today, such a system must be robust, it must provide the maximum in operating efficiencies and airspace utilization, it must work equally well at any location whether in radar view or not, it must be able to fail gently and with a maximum of safety margin, it must be sufficiently affordable for all airspace users, and it must do all of these things in a manner that does not aid terrorism nor espionage nor infringe civil liberties.

There are proposed systems that provide the benefits of ADS-B without the deficiencies and dangers. The flying community must speak out on this matter, only then will our concerns be heard and acted upon. My goal in authoring this paper has been to aid pilots, aircraft owners, system developers, and the general public in understanding the situation from a viewpoint different from the FAA.

Do you disagree? Or agree? Will you participate in a dialog?

Most messages I have received in response to this article have said, essentially, that I don't need to worry because there are people taking care of my concerns. I don't buy that argument because the RTCA document defining ADS-B contains all the problems and none of the solutions. On the other hand, there have been a few messages that are both reasonable and articulate, and I'd like to share them with you (click here). If you would like to contribute to the dialog, pleaseemail me and I'll post your message.

Who is doing this to aviation?

Here is the list of participants in RTCA Special Committee #186, the people who created ADS-B. If it is a success, here are the people you can thank. On the other hand, if ADS-B provides the structure for terrorist activities, for corporate espionage, and for General Aviation user fees, here are the people you can thank.

I have listed employees of the US government agencies in red, FAA contractors in pink, and general aviation representatives in blue. FAA frequently makes the point that RTCA is an "industry" group which "advises" the agency. As you can see for yourself, there are 271 members of SC-186. Of that 271, 58 (21%) are US government employees, mainly FAA employees. Another 35 (13%) are employees of think tanks operating on FAA money and under the direct FAA control. Beyond that are the many government hardware contractors such as Lockheed, Hughes, Honeywell, and Litton; the foreign aviation regulatory agencies; the airlines and their suppliers; plus a myriad of manufacturers, satellite communications companies, and others who want a piece of the ADS-B pie.

Balanced against all of the above are six (2%) members supporting General Aviation. Only six. Just think, 90% of the United States aircraft registry only gets 2% of the representation!

The List:

T. S. Abbott ..............NASA Langley Research Center
Brad Ajango ..............Rockwell Avionics & Communications
Jerry L. Anderson ......Federal Aviation Administration
Gregg W. Anderson ...Federal Aviation Administration
Brian Andrews ...........Federal Aviation Administration
Kenneth Arkind ..........Raytheon Company
Rose Ashford .............NASA Ames Research Center
Jonathan Baldwin ........Rannoch Corporation
Jack Ball .....................Lockheed Martin Aeronautical Systems
Melvin Barmat ..........Jansky/Barmat Telecommunications
Charlie Bautz ............Delta Air Lines, Inc.
Ed Bayliss ................MIT Lincoln Labs
Michael Beamish ......Pelorus Navigation Systms Inc.
August H. Beining .....Hughes Aircraft Company
Ricardo Benitez .......II Morrow Inc.
Richard Berckefeldt .AlliedSignal Aerospace Co. Inc.
Michael Biggs ..........Federal Aviation Administration
William A. Blake .....Federal Aviation Administration
Philip Bloom ............MITRE Corporation
Spiro Bocvarov .......Innovative Solutions Int'l
Chris Bogg ..............America West Airlines
Robert Boisvert .......MIT Lincoln Lab
David Bowen ..........UK Civil Aviation Authority
Jerry Bradley ...........System Resources Corporation
Robert Bradley ........Coleman Research Corporation
R. J. Braune ............RJ Braune & Associates, Inc.
Ed Briggs ................Delta Airlines, Inc.
Grover C. Brown ....U. S. Air Force
Sam Buckwalder .....AEEC (ARINC)
Don Bui ...................Federal Aviation Administration
Robert Buley ...........Northwest Airlines
Steven R. Bussolari ..MIT Lincoln Lab
James C. Byrum .......Cessna Aircraft Company
Douglas Campbell ....Syneca Research
Martin Capozzoli .....AlliedSignal Aerospace Co Inc
Gerry Caron ............Trimble Navigation
Ken Carpenter .........DERA, ATC Systems Group
Gerry Carson ..........Trimble Navigation Ltd
Francis Casaux ........DGAC/CENA
Rick L. Cassell ........Rannoch Corporation
Dan Castleberry ......Rockwell International
Mark Cato ..............Crown Communications, Inc
Wen Po Chan ..........Delta Airlines, Inc.
Divya C. Chandra ....MIT Lincoln Lab
Frank Cheshire ........American Airlines, Inc.
Lawrence F. Chesto .Aeronautical Radio Inc (ARINC)
Thomas Choyce .......Federal Aviation Administration
Joe Christman ..........Airborne Express
Vincent Chu .............Federal Aviation Administration
Jim Cieplak ..............The MITRE Corporation
Robert Clarke ..........Department of Defense JSC
B. Richard Climie .....Honeywell, Inc.
Bennett Cohen .........Rannoch Corporation
Glenn Colby ............U. S. Navy
Martin W. Cole .......Federal Aviation Administration
Joe Comeaux ..........ALPA
John G. Conkling .....Rockwell International
Donald Conners .......Litton Systems Aero Products Div.
Brad Culbertson .......Lockheed Martin
Chris Daskalakis ......Volpe National Transportation Systems Center
Richard DeSalvo ......IIT Research Institute/ECAC
Louis Desmarais .......International Air Transport Assn.
James E. Dieudonne .The MITRE Corporation
John J. Doyle ...........Aerospace Display Systems
Andre Dressler .........Independent Pilots Association (IPA)
Ann Drumm .............MIT Lincoln Labs
Keith Dutch ..............Federal Aviation Administration
Paul Ebert ................Adsystech, Inc.
Loma Elder ...............Innovative Solutions In't Inc.
Nagwa Elereby .........Douglas Aicraft Compay
Hans Englemier .........EUROCONTROL
Mark Erickson ..........ESC/GAT
Carl Evers ................Rannoch Corporation
Arthur Feinberg .........Federal Aviation Administration
Paul Fiduccia ............Small Aircraft Manufacturers Assn. (SAMA).
Bill Fischer ...............The Boeing Company
George W. Flathers ..Aircraft Owners & Pilots Assn. (AOPA).
Pat Fletcher .............Crown Communications, Inc.
Ken Foote ...............AvroTec, Inc.
Charmaine Franck ....Rannoch Corporation
Edward J. Fraughton .TERRASTARR
Robert H. Fuller .......Honeywell, Inc.
Julie Garloch ............Rockwell Collins
Jim Garoutte .............Federal Aviation Administration
Maro Gerlash ...........Daimler-Benz Aerospace
Doug Gibbs ..............BFGoodrich Avionics Systems
Rocklin R. Gmeiner ...Raytheon Company
Gerald Golden ...........Petroleum Helicopters Intl.
Robert W. Granville ..Federal Aviation Administration
Francis Grimal ..........EUROCAE
Paul Gross ...............Arthur D. Little
Robert Grove ...........II Morrow, Inc.
M. Guettier ..............DGAC-CENA
Hossein Habib .........TRW.Inc.
Christine Haissig ......Honeywell, Inc.
Angelynn Hall ..........Small Aircraft Manufacturing Assn. (SAMA)
Jonothan Hammer ....The MITRE Corporation
William Harman .......MIT Lincoln Laboratory
David Hartnett .........Federal Aviation Administration
Michael Hawthorne Federal Aviation Administration
Edgar Heath ...........Department of Defense JSC
Peter H. Heldt ........Daimler-Benz Aerospace
Douglas S. Helton ..Aircraft Owners & Pilots Assn. (AOPA)
Stephen B. Heppe ..Telenergy
Walter D. Hett .......Walter Hett & Associates
Dan Hicok ..............Rannoch Corporation
Robert Hilb ............United Parcel Service
Lori Hill ..................AlliedSignal Aerospace Co. Inc.
Harry J. Hodges ......Diversified Inti Sciences Corp.
Alison Hudgell .........ATC Systems Group DERA
Craig Hudson ..........II Morrow Inc.
Al Hughes ..............Federal Aviation Administration
Patrick Hunt ...........EUROCONTROL
Kris E. Hutchison ....Aeronautical Radio Inc (ARINC)
Robert Jackson .......Raytheon Systems Company
Michael Jenkins .......The MITRE Corporation
Rich Jennings ..........Federal Aviation Administration
Brian Johnson .........Stanford Telecommunications
Byron Johnson ........Federal Aviation Administration
Ron D. Jones ..........Federal Aviation Administration
Stanley Jones ..........The MITRE Corporation
Stephanie Jones .......Institute for Scientific Information
Clay Kemmerer .......Naval Safety Center
Robert B. Kerr ........Honeywell, Inc.
William Kight ..........Independent Pilots Assoc.
Beth Kimble ............Rockwell Collins UK Ltd.
Deborah Kirkman ...The MITRE Corporation
James A. Klein ........Rockwell International
Gregory W. Kuehl ...United Parcel Service
Phil LaRocca ...........Federal Aviation Administration
Luis Laboy ..............ECARS/LB&M
Charlotte Laqui .......The MITRE Corporation
Vie Lebacqz ............National Aeronautics & Space Administration
Nicolas Leyssieux ....Aerospatiale
George Ligler ..........Project Management Enterprises
Robert W. Lilley ......Illgen Simulation Technologies, Inc
Gary Livack ............Federal Aviation Administration
Howard M. Lock ...Aeronautical Radio, Inc. (ARINC)
Brandy Lohse .........Federal Aviation Administration
Charlotte Long ........Federal Aviation Administration
David Lubkowski ....The MITRE Corporation
Michael Lucia ..........Honeywell Inc.
Clark Lunsford ........The MITRE Corporation
Charles A. Lyon .....Airborne Express
Wayne MacKenzie ..Federal Aviation Administration
Donald J. Marsh ......II Morrow, Inc.
Tony Martin .............Honeywell, Inc.
Bill Matheson ..........Coleman Research Corp.
Alvah S. Mattox Jr. ..Aeronautical Radio, Inc. (ARINC)
James McDaniel .......Federal Aviation Administration
Ellen Meadors ..........TASC
Steve Meirowsky .....IFR Systems, Inc.
Raymond Meissner ...SETA
Bernard Miaillier ......EUROCONTROL
Charles Michaels .....Litton Aero Products
Joseph A. Miller .....Seagull Technology, Inc.
Carl Minkner.......... Honeywell, Inc.
John Chris Moody ..The MITRE Corporation
Kevin Moore .........Airservices Australia
Don L. Moore ........Smiths Industries
John Morgan ..........Honeywell, Inc.
Harold Moses ........RTCA, Inc.
Tom Mullinix ..........AlliedSignal Aerospace-Bendix/King
Colm Mulvey ..........National Avionics Limited
Anand Mundra .......The MITRE Corporation
Michael E. Murphy ..ATN Systems, Inc.
Todd Murr ..............Northwest Airlines, Inc
K. Prasad Nair .......Project Management Enterprises Inc.
Paul Newcomb .......Newcomb Communicatins, Inc.
Laurence Newman ..ALPA
Vincent Nguyen .......Federal Aviation Administration
Ronald E. Nidiffer ...Rockwell International
Aileen S. Nii ...........ISI Inc.
Johnny Nilsson ........SwedaviaAB
Lawrence J. Nivert ..Federal Aviation Administration
John O'Neill ............NIALL
Richard Olson ..........Federal Aviation Administration
Lee A. Olson ...........Federal Aviation Administration
Vincent A. Orlando ..MIT Lincoln Lab
Thomas Pagano .......Federal Aviation Administration
C. C. Parkinson Jr. ..DCS, Inc.
Robert H. Passman ..Federal Aviation Administration
Doyle T. Peed .........The MITRE Corporation
Michael C. Petri .......Federal Aviation Administration
William F. Petruzel ...Federal Aviation Administration
H. Robert Pilley .......Deering Sys. Design Consultant
Paul Phillips .............Rockwell International
Pierre Pinson ...........STNA
Pascal Ponsot ..........Aerospatiale Avions
J. David Powell .......Stanford University
Thomas A. Prevost ...Federal Aviation Administration
Carmine Primeggia ....Federal Aviation Administration
Paul J. Prisaznuk ......Aeronautical Radio, Inc. (ARINC)
Paul Quick ...............Federal Aviation Administration
Jerome Rascol .........Aerospatiale Avions
John W. Rathgeber ...Lockheed/Martin
Sethu Rathinam ........Rockwell-Collins,lnc.
Robert W. Renoud ...Aeronautical Radio, Inc. (ARINC)
Thomas Rosback .....AlliedSignal Aerospace Co Inc
Rudolph M. Ruana ...Jeppesen Sanderson
Richard Rucker ........Solo Engineering
Marc-Philippe ..........Rannoch Corporation
William M. Russell III ..Russell Systems
Michael P. Russo .....Aeronautical Radio Inc (ARINC)
Robert H. Saffell ......Rockwell International
Ronald G. Sandholm ..MIT Lincoln Lab
James F. Savard ......Jeppesen Sanderson
Herbert W. Schlickenmaier ..National Aeronautics & Space Administration
Carl E. Schwab ........Cardion, Inc.
Robert E. Semar .......United Airlines
Mike Sharpies ..........Defense Research Agency
Dave Sim .................Transport Canada
Georges Heni Simon ..Sextant Avionique
Peter Skaves ............Federal Aviation Administration
Charles W. Sloane ...Federal Aviation Administration
Alexander Smith ......Rannoch Corporation
Bernald S. Smith ......Soaring Society of America (SSA)
Gilbert M. Smoak ....Rockwell International
Kelvin L. Soico ........Federal Aviation Administration
John A. Sorensen ......Seagull Technology, Inc.
Rick Stead ...............Aeronautical Radio, Inc. (ARINC)
Cyro Stone .............AlliedSignal, BGA
Rocky Stone ..........United Air Lines Inc.
Robert C. Strain .....MITRE Corporation
John Studenny ........Canadian Marconi Company
Bob Swensson .......MITRE Corporation
Earl Swinson ..........NAVAIR
Nick Talotta ...........Federal Aviation Administration
Donald J. Taylor ......Experimental Aircraft Association (EAA)
Tom S. Teetor ........Defense Concept Associates Inc
Ron F. Testa ..........BFGoodrich Flight Systems, Inc.
Rhonda Thomas ......Federal Aviation Administration
Daniel H. Tillotson ..Aeronautical Radio, Inc. (ARINC)
Tracy Tong ............The Boeing Company
Robert Tom ...........Delta Airlines
Michael Toumas .....Lockheed Martin
Nguyet Trang ..........The Boeing Company
Jim Triantos ...........Trios Associates
Brian Tucker ..........Aeronautical Radio, Inc. (ARINC)
Per Usiand Kongsberg ..Gruppen ASA Aerospace
Hank Valentine ........H Harrison Valentine, Inc
Paula M. Van Balen ..Harris Corp., ATC Systems Div.
Garth Van Sickle .....DCS, Inc.
Stephen P. VanTrees ..Federal Aviation Administration
Antony Vaudrey .....UK Civil Aviation Authority
Chris Villani ............National Satellite Networks
Michael J. Wade .....TRW, Inc.
Marvin C. Waller ....NASA Langley Research Center
Anthony W. Warren ..The Boeing Company
Jerry Watson .............AlliedSignal Aerospace
Barry Webb ..............AlliedSignal Aerospace
Charles H. Wehage ...Rockwell International
Bob Whinnery ...........Lockheed Martin
Benjamin T. White .....American Airlines, Inc.
Brian E. White ..........The MITRE Corporation
Robert R. Wilson......Harris Corporation
Warren J. Wilson .....The MITRE Corporation
Debra Winchester ....Hughes Aircraft Company
Marcus Wolf ............Federal Communications Commission
Christopher J. Wolf ..Federal Aviation Administration
George Woltz ..........U. S. Air Force
Robert Wonderlich ...Lockheed Martin Quadratek
David Wong ............GEC-Marconi Hazeltine
Peter Wood ..............Iridium, Inc.
Brian Woods ............Loral Federal Systems
Laurie Wyatt ............Honeywell, Inc.
Sandy Wyatt ............Honeywell, Inc.
Katheryn Ybarra ......Honeywell, Inc.
Steve Young ............NASA Langley Research Center
Jose H. Yu ...............Information Integration, Inc.
Andrew D. Zeitlin .....The MITRE Corporation

(Note: This list of SC-186 members is believed to be accurate as of June 2000, based on publically available data. To submit corrections, pleaseemail Darryl Phillips.)

Links to other ADS-B information available on the web:

Other contrasting opinions on ADS-B may be foundhere.

http://www.sensis.com/docs/9/ ...This is a beautiful color brochure in PDF format, study it carefully in light of the above scenarios.

http://littongcs.glyphix.com/products/3iff/iffqa.html...Information from Litton on Modes A/C/S as well as the military-only transponder modes

http://www.govcomm.harris.com/airground/ads.htm

http://www.faa.gov/and/and300/datalink/navsur/adsb.htm

http://www.ads-b.com/

http://www.rtca.org/comm/sc186.htm

http://www.sac.honeywell.com/atsrel.html

And if you think ADS-B is bad, check out the documented problems with Air Traffic Control radar:

http://home.columbus.rr.com/lusch/aopa_article01.html

http://home.columbus.rr.com/lusch/....Written by FPL controller and experienced pilot Tom Lusch, this site is a_must_ for anyone interested in safe flight.

http://home.columbus.rr.com/lusch/talotta.html

First written March 1999

revised July 2000

by Darryl H. Phillips

AirSport Corporation - 1100 West Cherokee - Sallisaw OK 74955 voice: 918-775-4010 - fax: 918-775-4000

email darryl@airsport-corp.com

Permission is granted to reproduce this document in print or electronic form, provided it is kept intact without changes, including this notice. Other sites are encouraged to link, or better yet, to repost this document on their sites.