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Special conditions

Special Conditions; British Aerospace (Commercial Aircraft) Ltd. Model 4100 Series Airplanes; Lightning and 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 September 8, 1991 for British Aerospace. System: instruments and avionics.

What it applies to

Applicant
British Aerospace
Makes
British Aerospace
Models
—
Published
September 8, 1991
Effective
October 8, 1991
The FAA's document
On the FAA's site

The FAA's summary their words, unchanged

These special conditions are issued for the British Aerospace (Commercial Aircraft) Ltd. Model 4100 series airplanes. These airplanes are equipped with high-technology digital avionics systems that perform critical or essential functions. The applicable regulations do not contain adequate or appropriate safety standards for the protection of these systems from the effects of lightning and high-intensity radiated fields (HIRF). These special conditions contain the additional safety standards that the Administrator considers necessary to ensure that the critical and essential functions that these systems perform are maintained when the airplane is exposed to lightning and HIRF.

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