The Civil Aviation Authority (CAA) is reminding air passengers that using mobile phones is still forbidden on nearly all flights. Some airlines – including BMI, Ryanair, Air France, TAP Portugal, Qantas, Emirates and British Airways - are currently using or planning in-flight mobile phone systems on their aircraft, but most flights still prohibit the use of mobiles. The UK’s aviation regulator points out that any passenger who disobeys a cabin crew instruction to turn off a mobile phone could be prosecuted. Research carried out by the CAA has found that using mobile telephones in aircraft can adversely affect navigation and communication functions, producing significant errors on instrument displays. [News release; research (pdf)]