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Special conditions · aircraft

Special Conditions: Learjet Model 35 series; 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 October 3, 2005 for Avcon Industries INC., covering the 35, 35A (C-21A). System: instruments and avionics.

What it applies to

Applicant
Avcon Industries INC.
Makes
Learjet Inc.
Models
35, 35A (C-21A)
On this site
Learjet 35 161 registered
Published
October 3, 2005
Effective
October 4, 2005
The FAA's document
On the FAA's site

The FAA's summary their words, unchanged

These special conditions are issued for Learjet Model 35 series airplanes modified by Avcon Industries Inc. 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 new Kollsman 24771 Air data computers and Thommen AD30 displays. 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.