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Special conditions

Special Conditions: Boeing Model 727-100 / -200 Series 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 March 18, 2004 for Aircraft Systems & Manufacturing. System: instruments and avionics.

What it applies to

Applicant
Aircraft Systems & Manufacturing
Makes
Boeing
Models
—
Published
March 18, 2004
Effective
March 4, 2004
The FAA's document
On the FAA's site

The FAA's summary their words, unchanged

These special conditions are issued for Boeing Model 727-100 / -200 series airplanes modified by Aircraft Systems and 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 Collins Horizontal Situation Indicator (HSI) that performs critical functions. The applicable airworthiness regulations do not contain adequate or appropriate safety standards for the protection of this system 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.