FAA Order 8130.2M — Operating Limitation 57
Appendix D · Table D-1 · p. p191
Instrument flight rules (IFR) operations are prohibited unless the instruments specified in § 91.205(b) and (d) are installed, operational, compliant with the performance requirements of, and maintained per the applicable regulations. If the aircraft’s instruments are in compliance with these requirements and the aircraft or engine manufacturer does not prohibit IFR operations, then IFR operations are permitted, but limited to visual meteorological conditions.
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