Making Airliners Safer with Password-Protected Instruments

There seems to be a very simple modification that could quickly and inexpensively be made to all airliners, which would make the danger of 9/11 type terrorism impossible.

Since you are on the Internet, you are familiar with computers, and you probably know what "passwords" are. If you share a computer with someone else, or if you are in an office where others could possibly sit down at your computer, you probably have password protection active. It is a standard feature of ALL Windows computers and most other computer platforms as well. Until you type in the necessary password, which generally means that YOU have to be sitting there, your screen stays dark and the keyboard is not functional.

Consider this situation: Each of the two pilot positions in an airliner has such password protection. Unless the person sitting in that seat inputs the correct password, the controls could not be operated and the instruments would appear blank. Before the pilots began their pre-flight checklist, they each had to type in a specific password (different for the two people, and provided to them at home on the phone prior to their flight). From then on the instruments and controls would act absolutely normally.

On long flights, soon after takeoff, the auto-pilot is nearly always engaged, to actually control the aircraft and keep it at a constant altitude and on a constant heading, until it is disengaged, usually shortly before landing. This means that, beginning only a few minutes after takeoff, the auto-pilot keeps the aircraft safe and level for the majority of the flight.

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(this concept was first composed on 9/12/01 and placed in a web-page on 11/9/01.)

Now imagine ANY unexpected activity in the aircraft, whether an incident involving a passenger or flight attendant in the cabin, or even an unexpected entry of a passenger into the flight deck. Any of several "panic buttons" could immediately be activated by the pilots. They could specifically press a blanking button, similar to what you do with an office computer when you need to use the rest room, so no one could see what you had been working on while you were gone. Also, the pilots' seats could have weight sensors that had the same function, where if a pilot got up, ir even lifted his weight from the seat, his controls would instantly go blank. The aircraft would be perfectly safe, since the auto-pilot would keep if safe for hours to come, going on a straight and level course.

What could a potential hijacker or terrorist now do on the flight deck? The controls would be disconnected, and the instruments blank. If he should kill or disable the pilot, he still cannot alter the path of the aircraft, and cannot even disengage the auto-pilot. No matter what he would do, the aircraft would stay safe for several more hours.

The ONLY possibility of a hijacker or terrorist actually being able to change the flight path of the aircraft would have to involve the active participation of at least one of the two pilots. We all have absolute faith in ALL commercial pilots that none of them would ever participate in events like 9/11/01. So, the original pilots could not be killed or disabled, because at least one of them would have to participate in the terrorist activities, and we know they would never do that.

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In the sick minds of terrorists, they could conceivably threaten, torture or kill the flight attendants and/or passengers, or even one of the flight crew. But the fact that the control of the aircraft's course required one actively participating pilot, ensures that a commercial aircraft could never again be used as a weapon.

Notice that this approach does not actually require impregnable doors on the flight deck, or handguns or tazers or any other weapons on board. The fact that a terrorist could not possibly alter the course of the aircraft removes the incentive of even trying to use it as a weapon. Better than that, as soon as all commercial airliners had this system, and the news of it was publicized, potential terrorists would know ahead of time that there would be no success possible in any hijacking plan.

What is involved to install such a system? VERY little! Since the computer programming already exists in ALL of hundreds of millions of computers, and only represents a few lines of computer code, adding those software lines into the aircraft's computers should be a one-minute job! Since the programs have been in use for so many years, no R&D cost or time would be necessary. It is likely that some existing button on the control areas could be used as a "panic button", but if not, installing a simple pushbutton switch should only take a few minutes at most. Keep in mind that Bank Tellers already have such buttons on the floor or under the counter such that they could alert Police. If weight sensors were to be used for the pilots' seats, maybe a half-hour of labor would be involved. All in all, in less than an hour, with far less than $20 of materials necessary, ANY airliner could have this terrorist deterrent system.

I first realized all of this on 9/12/01, and very soon after that, I tried to give it to a number of Airlines, Boeing, the FBI, a number of Senators and Congressmen, and several network TV news organizations. It was obvious that the flying public would be terrified at the possibility of this happening again, and that the effect of huge numbers of people stopping their flying would be terrible to the airlines, to business, and to the economy, as well as to the overall confidence of our people. I tried VERY hard to let the "powers that be" know right away about this very quick and simple way to absolutely ensure that an aircraft could never be used as a weapon again.

Even more importantly, a Press Release by any airline that did this, or by any high authority in our government, would have done wonders to our National confidence right then. If such a spokesperson walked into the flight deck of an airliner with this modification, and the pilots, acting as though he was a terrorist, momentarily got up out of their seats and/or touched the disable button, any viewer would see the instruments instantly go blank. When our spokesman went over and sat down, he would show that the controls did not change anything, and he would point to the auto-pilot light that showed that everything was perfectly safe for now.

If the flying public saw such a demonstration, they would all immediately see how no terrorist could possibly alter the course of the aircraft, and they would not have been so terrified at boarding another airliner. They would also know that the airplane was destined to go level and straight for at least several hours, giving the passengers and crew a long time to figure out how they could deal with a few hijackers or terrorists. And even if this worst-case scenario occurred, and it took an hour to overcome the terrorists, and if the pilots had all been killed, if some flight attendant or passenger could use the radio headset, the ground could give the necessary password after calm had been re-established, and someone could then control the aircraft in order to land it safely.

I found it incredibly frustrating to not have any of dozens of people even respond to my calls or e-mails. Instead, they collectively did the "government" thing and started hearings and doing studies. Ultimately, it will probably be that the flight deck on airliners will be a fortress, and all kinds of complicated and expensive modifications will eventually be made to all airliners. If any of them would have ever listened, they could have spent less than $20 per aircraft and not needed all that. Better yet, the flying public would have quickly been assured that no possible terrorist use could ever occur again, and the airline industry would not have been hurt so bad financially.

As always before, I make this modification available to all parties, at no cost, in the spirit of community. I can only hope that one or more people who actually have influence will some day find this page and consider it for inclusion into airliners. The American flying public deserves it.

First conceptualized, 9/12/01.
First described to various leaders, 9/14/01
First presented as this web-page, 11/9/01

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C Johnson, Theoretical Physicist, Physics Degree from Univ of Chicago