Ken During the mid 90s we manufactured equipment that was installed on 747s which was tested to RTCA/DO-160C and all the cables on that aircraft for that system were unscreened. Boeing informed us that they would not permit screened cables due to the increase in weight that would then affect the passenger cargo carrying capability of the aircraft.
I know that rf signals are coax and that certain control signals are screened for flight critical systems. It isn't so bad for newer aircraft but some of the older ones that use Omega and the earlier flight nav systems have reported interfernce with these systems and the autopilot. When the passengers have been requested to switch off their equipments the interference has dissappeared. It has been found through surveys carried out on aircraft by ERA and QinetiQ that the interfernce appears to get into these systems from certain locations within the aircraft where cable run reside under certain seats. Incidents of interfernce breakthough on coms have been more difficult to identify. Investigations are still being carried out. If you want more data suggest you get in touch wuth Dr Nigel Carter @ QinetiQ or Eric Stevens @ ERA. Regards Andy Andrew Price Principal Development Engineer (EMC Specialist) BAE SYSTEMS Avionics A125 Christopher Martin Road Basildon, Essex SS14 3EL tel: +44 (0) 1268 883308 email: andrew.p.pr...@baesystems.com *************************************************************************** This email and any attachments are confidential to the intended recipient and may also be privileged. If you are not the intended recipient please delete it from your system and notify the sender. You should not copy it or use it for any purpose nor disclose or distribute its contents to any other person. *************************************************************************** ------------------------------------------- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on "browse" and then "emc-pstc mailing list"
