This AC paragraph is final and will be included in the upcoming Change 2 update.
AC 29 APPENDIX B. AIRWORTHINESS GUIDANCE FOR ROTORCRAFT
INSTRUMENT FLIGHT
* * * * *
b. Procedures.
* * * * *
(8) Cockpit Arrangement.
* * * * *
( v) Electromechanical Displays. The requirements of Appendix B to Part 29 in sections, VIII.(b)(5)(i) through (iii) are the same requirements as those found in § 29.1333. Prior to Amendment 29-24 and § 29.1333, this requirement was titled “Duplicate Instrument Systems,” and its provisions were intended to apply when duplicate flight instruments were required by any operating rule. Due to the increased complexity of instrumentation that was available and being used, it was considered appropriate to amend the provisions of this requirement to more appropriately consider the extreme range of operational environments to which rotorcraft were being routinely exposed. It is the intent of Part 29, Appendix B, VIII.(b)(5) to prevent degrading of the first pilot’s instrument system, or the only pilot’s instrument system in a single-pilot-approved rotorcraft, by not permitting peripheral systems to be connected to it. In addition, equipment must not be connected to operating systems for the second pilot’s required instruments unless it is extremely improbable that failure of such additional equipment would affect that operating system. Similar provisions are also included in § 29.1333.
( vi) Advanced Display Systems. The increased use of microprocessor technology in avionic systems has resulted in the use of computer-generated graphics to replace conventional electromechanical instruments. These displays may replace individual instruments or may integrate several flight critical parameters into single displays. For display of redundant information, “crosstalk” between the pilot and copilot displays and supporting systems has been allowed to provide detection and annunciation of faults or “miscompare” of critical flight information. A level of safety finding equivalent to that level of safety provided by Part 29, Appendix B, VIII.(b)(5)(i) through (iii) may be possible through the implementation of integration technology that will assure that failure of one system does not and can not adversely affect the other system. For those installation designs that employ integration technology, adequate system testing and any analysis necessary must be conducted to assure that failure of one system will not adversely affect the other system when demonstrating compliance to the minimum safety level established by Part 29, Appendix B, VIII.(b)(5)(i) through (iii) and § 29.1333.
* * * * * Page 17