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Special conditions

Special Conditions: Bell Helicopter Textron Canada Model 427 Helicopters, High Intensity Radiated Fields

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 May 19, 1999 for Bell. System: other and general.

What it applies to

Applicant
Bell
Makes
Bell
Models
—
Published
May 19, 1999
Effective
May 10, 1999
The FAA's document
On the FAA's site

The FAA's summary their words, unchanged

This special condition is issued for Bell Helicopter Textron Canada (Bell) Model 427 helicopters. These helicopters will have a novel or unusual design feature associated with the installation of electronic systems that perform critical functions. The applicable airworthiness regulations do not contain adequate or appropriate safety standards to protect systems that perform critical control functions, or provide critical displays, from the effects of high-intensity radiated fields (HIRF). This special condition contains the additional safety standards that the Administrator considers necessary to ensure that critical functions of systems will be maintained when exposed to HIRF.

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