Ini saya kutip dari: http://www.indoflyer.net/indoforum/tm.asp?m=96306&mpage=1&key=handphone
yang membahas pengaruh handphone pada saat terbang. Banning the use of Cellphones in flight: 1. The conspiracy theory: 1.a. Supaya pada nggak cerewet dipesawat. Dah bayar kelas bisnis, mau siapin presentation pas dipesawat, eh, disebelah ada orang cerewet teriak2 di HP... Oh Bugga! 1.b. Increased derivative sales... pake telpon yang ada di pesawat dan bayar US$3 - 10 per minute tergantung airlinenya. 2. The fictional version: 2.a. It'll interfere the controls and electronic signals and make it fall out of the sky. This is fiction! Salah satu requirement dari sertifikasi adalah "resistence to interference"... Keganggu sih wajar, tp jatuh karena itu? Errr... No! 2.b. It has been proven to cause fatal interference. No... tests have failed to replicate the interference. However, it IS STRONGLY SUSPECTED with scientific basis, that cellphones MAY CAUSE interference. This risk, especially on instrument approach situation is what causes the ban! 3. Known fictional accidents where cellphones were accused falsely: 3.a. Tambolaka incident. Carrier has a history of IRS abnormalities. If NAV position update and correction to IRS position was used, it is inconceivable that interference from a cellphone block out NAV signals OR cause NAV signals to have been mistranslated to the extent of >100NM error. If an interference was the cause of the deviation, crew should have noticed a degradation in RNP and a diverging FMC position from each source. 3.b. Wrong landing at Tabing instead of Minangkabau. It is impossible for a cellphone to cause the deviation. Whilst interference would have caused a slope mistranslation, the glideslope would still create an error slope to the glideslope transmission. Same goes to the localizer. Crew approach monitoring procedures should have picked up abnormal descent rates or headings. Actual cause is known but somehow is not allowed to be released to the public. 4. The facts: 4.a. Cellphones use digital signals. New aircraft using digital FBW and FADEC is known to have been affected by interference, especially in low altitude (critical phases). 4.b. Erroneous fuel readings caused by cellphone interference have been noted. 4.c. Bigger risk lies on systems WITHIN the airframe and not signals the aircraft received from outside the airframe (metal cage effect). 4.d. Gw pernah nyalain HP pas disebelah IRU dan disebelah DGPS antennae... (both unshielded) resulting in "Funny" effects. "Tests" done on ground and inflight, no life endangering deviations noted. 4.e. It is BLOODY ANNOYING to hear handphone signals while talking on the radio! 5. The Law: 5.a. If it's Illegal, IT'S ILLEGAL! It's the LAW! 5.b. Failure to comply to company regulations or crew instructions MAY CAUSE in you committing an unlawful disobedience to the flight crew, which is enough for a criminal prosecution. Gerry ------------------------------------ The cell phone ban went into effect in 1991, mostly to eliminate the possibility that cell phone calls on airplanes would interfere with cell conversations on the ground, as well as with the airplane's radio communications. The study, by CMU's Department of Engineering and Public Policy, found that the use of cell phones and other portable electronic devices can interfere with the normal operation of critical airline components, even more so than previously believed. Researchers concluded that such devices can disrupt the operation of cockpit instruments, including the Global Positioning System receivers that are becoming more common in helping to ensure safe landings. The FCC cited effects of "frequency re-use," which is a fundamental cell phone principle that's helped mobile phones proliferate worldwide. The signal from a cell phone doesn't go on forever; the energy to propel it dissipates after a number of miles, and it dissipates more quickly if it bounces off buildings, hills and other obstacles. This allows the same frequencies to be re-used by operators in different markets sometimes just a few miles apart. A cell phone signal falling to Earth from a phone aboard a plane encounters no significant obstacles to slow it down, so it's strong enough to reach the ground and find a network on its particular frequency. But if the airwaves belong to a different operator, there's likely to be "noise" and other forms of interference for everybody, the FCC believes. -------------------------------------------------- Official Mailing List: Porsenipar ke IV Tahun 2007 -=== Perumahan BDB2 dan BDB3, Cibinong, Bogor ===- -= Menjiwai Semangat Kebangsaan dengan Prestasi =- | Official Website: http://www.porsenipar.web.id | ------- Porsenipar Media Center: 6849-6001 -------
