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Special conditions

Special Conditions: Boeing Model 727-200 Airplanes; 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 9, 2001 for Aircraft Systems & Manufacturing. System: instruments and avionics.

What it applies to

Applicant
Aircraft Systems & Manufacturing
Makes
Boeing
Models
—
Published
September 9, 2001
Effective
September 23, 2001
The FAA's document
On the FAA's site

The FAA's summary their words, unchanged

These special conditions are issued for Boeing Model 727-200 airplanes modified by Aircraft Systems & Manufacturing. These modified airplanes will have a novel or unusual design feature when compared to the state of technology envisioned in the airworthiness standards for transport category airplanes. The modification incorporates the installation of a new electronic air data system, consisting of an electronic Horizontal Situation Indicator (HSI) and dual air data computers, that performs critical functions. The applicable airworthiness 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 contain the additional safety standards that the Administrator considers necessary to establish a level of safety equivalent to that established by the existing airworthiness standards.

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