Page 7-2 400W Series Installation ManualRev. G 190-00356-027.1.2 Safety Assessment ConsiderationsThis STC requires that the modified aircraft meet navigation and communication availabilityrequirements at the aircraft level appropriate to the failure condition category, aircraft category and class.TSO-C146a defines loss of function of en route, terminal, non-precision approach, or precision approachnavigation data as a major failure condition. AC 23.1309-1C provides guidance for IFR airplanes thatclassifies total loss of function as a major failure condition, and loss of primary means of function asminor if two navigation systems are installed. One method to meet the major failure condition for loss offunction is to have redundant systems. It is recommended that the aircraft be equipped with at least twoindependent navigation receivers and two independent communication transceivers for IFR use. Forindependent navigation systems, two 400W Series units may be used, or a combination of 400W/500WSeries and an independent NAV/COM unit may be used. This will support System Safety Assessment ofassumptions. Refer to AC 23.1309-1C.7.1.3 Previous Operational ApprovalsThe installation of a 400W Series unit into an aircraft does not alter the operational approvals previouslygranted to that aircraft. Additional operation approvals may require FAA evaluation of all the systemsinstalled in a particular aircraft and is outside the scope of 400W/500W Series STC SA01933LA.7.2 InstallationThe conditions and tests required for TSO approval of this article are minimum performance standards. Itis the responsibility of those installing this article either on or within a specific type or class of aircraft todetermine that the aircraft installation conditions are within the TSO standards. TSO articles must haveseparate approval for installation in an aircraft. The article may be installed only if performed under 14CFR part 43 or the applicable airworthiness requirements.The 400W Series GPS/WAAS receiver, when installed with the appropriate antenna listed inSection 1.4.8, is compatible with aircraft equipped with SATCOM when installed in accordance to thismanual.7.2.1 GPS AntennaThe GPS/WAAS receiver is compatible with the GPS antennas listed in Section 1.4.8. Antenna selectionmay affect operational limitations.7.2.2 Antenna Installation – GeneralStructural mounting of the GPS/WAAS antenna is not included in this installation manual. For mountingthe GPS/WAAS antennas, refer to the Garmin GA Antenna AML STC SA01695SE or other FAAapproved installation data.7.2.3 Equipment Interfaced to the 400W Series Unit400W Series unit interfaces to aircraft systems other than those identified in this installation manual areoutside the scope of this manual and may require further evaluation for certification and/or other FAAairworthiness approval.7.2.4 Preservation of Previous SystemsIt is the installer’s responsibility using data provided in this manual identified in 400W/500W SeriesAML STC SA01933LA to preserve the essential characteristics of the aircraft in accordance with theaircraft manufacturer’s original design and the requirements of 14 CFR Part 23. This includes thepreservation of multiple power buses, which reduce the probability of interrupting power to essentialinstruments and avionics. For aircraft certified under 14 CFR Part 23, post amendment 41, use of the400W Series unit for IFR operations requires a functional redundant electrical power system for theprimary navigation unit.
