AD 2020-12-06

final rule
Data completeness: 70%

Airworthiness Directives; Gulfstream Aerospace Corporation Airplanes

AD Number
2020-12-06
Status
final_rule
Effective Date
Product Category
aircraft
Docket
Docket No. FAA-2019-1060
FR Citation
85 FR 36143

Applicability

TypeManufacturerModelDetails
aircraft Gulfstream Aerospace Corporation Airworthiness Directives; Gulfstream Aerospace Corporation Airplanes

Unsafe Condition

The supplier compromised the seals during assembly of the electro-hydraulic servo valves, which allows moisture to enter the valve. During cold soak conditions, the moisture forms ice crystals in the servo valve armature air gaps, which may cause the valve armature to displace to a non-neutral position.

AI-generated summary from the source AD text. Verify against the official source before acting.

Required Actions

Replacing the nose wheel steering servo valve manifold, incorporating revised operating procedures into the airplane flight manual (AFM), doing a records inspection for any incidents of un-commanded nose wheel steering turns, and reporting the results to the FAA.

AI-generated summary from the source AD text. Verify against the official source before acting.

Compliance Time

Before further flight

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Affected Aircraft

All Gulfstream Model G-IV airplanes.

AI-generated summary from the source AD text. Verify against the official source before acting.

Source: Official FAA Source ↗

Retrieved: Apr 6, 2026

Rights: U.S. Government Public Domain

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