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Special conditions

Special Conditions: Modified Cessna 551 Airplane: High Intensity Radiated Fields (HIRF)

Special conditions are rules the FAA writes for one design when the standard certification rules do not cover something new about it. These were published January 1, 1992 for Electrosonics. System: instruments and avionics.

What it applies to

Applicant
Electrosonics
Makes
Cessna
Models
—
Published
January 1, 1992
Effective
December 22, 1991
The FAA's document
On the FAA's site

The FAA's summary their words, unchanged

These special conditions are issued for the Cessna Model 551 airplane modified by ElectroSonics Division of AiRadio Corporation of Columbus, Ohio. This airplane is equipped with high-technology digital avionics systems that perform critical functions. The applicable regulations do not contain adequate or appropriate safety standards for the protection of these systems from the effects of high-intensity radiated fields (HIRF). These special conditions provide the additional safety standards that the Administrator considers necessary to ensure that the critical functions performed by this system are maintained when the airplane is exposed to HIRF.

Source: FAA special conditions (final) from the Dynamic Regulatory System; the Federal Register carries the same notices.