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		'PROJECT ACHILLES' REPORT
	When you make a cell phone call, the first thing that happens is that your cell phone needs to contact a transponder. Your cell phone has a max transmit power of five watts, three watts is actually the norm. If an aircraft is going five hundred miles an hour, your cell phone will not be able to 1. Contact a tower, 2. Tell the tower who you are, and who your provider is, 3. Tell the tower what mode it wants to communicate with, and 4. Establish that it is in a roaming area before it passes out of a five watt range. This procedure, called an electronic handshake, takes approximately 45 seconds for a cell phone to complete upon initial power up in a roaming area because neither the cell phone or cell transponder knows where that phone is and what mode it uses when it is turned on. At 500 miles an hour, the aircraft will travel three times the range of a cell phone's five watt transmitter before this handshaking can occur. Though it is sometimes possible to connect during takeoff and landing, under the situation that was claimed the calls were impossible. The calls from the airplane were faked, no if's or buts. 'Project Achilles' Report Part One - January 23rd 2003 Preliminary low-altitude cellphone experiment January 23 2003; 4:35 - 5:40 pm Civic Airport, London, Ontario, Canada Equipment: aircraft: Diamond DA20/C1 Katana two-seater engine: 125 hp fiberglass/carbon fiber composite body & airframe weight fully loaded: 1630 lbs cellphones: one Motorola model "120 CDMA" cellphone (A) two Motorola "i1000 plus" cellphones (B) (both fully charged at flight time) The flight plan consisted of four "laps," elongated circuits (shaped like a paperclip) over London, Ontario airspace. Each lap was about seven to eight miles long and two to three miles wide. Three calls were made on each of two straight legs in each lap. Calls alternated between cellphone A and cellphone B. A second i1000, intended for use at higher altitudes, slipped to the cockpit floor and could not be retrieved in those cramped quarters. A check of battery levels of the first i1000, however, showed that there had been no significant power drain on the unit. Note: "altitude" means aboveground altitude, not height above sea level, as recorded by the altimeter. Results: Lap 1 @ 1,100 feet altitude: 1st leg:A to business numberno connection?B to business number1 min. completeA to business number1 min. complete2nd legB to home numberno connection?A to home number(broken) completeB to home numbercompleteLap 2 @ 2,100 feet altitude: 1st leg:A to home numberno connection?B to home numberno voice, just a "beep"A to home numberno connection?2nd legB to home number1 min. completeA to home numberno voiceB to home numberno voiceLap 3 @ 3,100 feet altitude: 1st leg:A to home numbermissed making the callB to home number"system busy"A to home numberincomplete2nd legB to home number"please wait: CLEARNET"A to home numberincompleteB to home numbercall made late, incompleteLap 3 @ 3,500 feet altitude: A to home numberincompleteB to home numbercomplete, but breaking upAfter the third call, I decided that the cockpit was too noisy to hear the message system, so I changed my plan and called home (my wife), instead. Calls to the business number were recorded by the message system. Two calls made it through. Of the 17 calls to the home number, only about ten calls got through. In three of these, we had a conversation (of sorts) and the rest were just white noise. (no record of which) Summary: In the preliminary test, only five of the 16 (attempted) calls resulted in any meaningful voice contact. In at least two of those calls, no connection whatever could be established with cellsites below. The composition of the Diamond Katana (manufactured right here in London, Ontario) makes it almost transparent to EM radiation at radio wavelengths and the results of this experiment are therefore optimal. Aircraft with metal skins will undoubtedly fare rather worse in the percentage of calls making it through. Altitude RangeRange in FeetCall Success RatePercentage Success Ratelow altitude(1,100'- 2,100')4/1233%mid altitude(3100 - 3500')1/714%Conclusion: The purpose of this experiment was to probe the effect of altitude on cellphone service and to iron out wrinkles in experimental procedure. In the first instance, it looks as though there might well be a decline in service with increasing altitude. The phenomenon must now be mapped more carefully. As far as operating procedures is concerned, it is probably best to make calls to a number you know well, to be familiar with the various status messages on each cellphone display screen, and to have someone at the other end who can log the time of the call, as well as to summarize the content. (The cockpit in most light aircraft is so noisy that one cannot always hear a voice at the other end, although I did hear my wife talking somewhat clearly on two occasions.) Also, it is important to be very organized, having a special carrier case for cellphones, writing/recording materials, etc. The airspeed of the Katana was just a little fast for me to comfortably make the calls and stay organized at the same time. Two of the calls were made rather late in the current lap, even as we began to climb out to the next one. It would be better to have a separate person operating the cellphones. We also need a meaningful call classification system to fill the gaps between complete failure and an audible conversation. All calls were handled by the Bell Mobility Network, which has some 25 cellsites operating in the London area. I have now located all the cellsites in London, Ontario, thanks to a very helpful set of maps provided by a local cell phone aficionado: <www.arcx.com/sites/> Plans are now under way for Part Two <project_achilles_report_2_030225.html>. This will involve a Cessna four-seater (with an aluminum skin), five or six cellphones of various types, an expert to operate them on my queue, and a flight plan that will explore the effect up to 10,000 feet beyond which, according to one airline pilot, there is absolutely no hope of getting through. A. K. Dewdney (with thanks to Corey Barrington, pilot with empire Aviation) Cont ...
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