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AC 20-41A - Substitute Technical Standard Order (TSO) Aircraft Equipment

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20-41A - Substitute Technical Standard Order (TSO) Aircraft Equipment

Date Issued
April 05, 1977
Responsible Office
AIR-120,  Aviation Safety - Aircraft Certification Service, Aircraft Engineering Division
Sets forth an acceptable means for complying with rules governing aircraft equipment installations in cases involving the substitution of technical standard order equipment for functionally similar TSO approved equipment.