AD 90-21-18
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Gulfstream Aerospace Corporation | G-IV | Airworthiness Directives; GULFSTREAM Model G-IV Series Airplanes |
Unsafe Condition
In-flight failure of avionics equipment due to water intrusion through the rubber radome seal and aerodynamic seal.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Install additional sealant on the upper portion of the radome and fuselage mating structure, inspect the integrity of the rubber radome seal and aerodynamic seal, and replace or repair defects found in the seals prior to further flight, all in accordance with ASC 183.
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Compliance Time
Within 25 hours time-in-service or within 30 days after the effective date of this AD, whichever occurs later.
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Affected Aircraft
Gulfstream Aerospace Corporation Model G-IV series airplanes, Serial Numbers 1000 through 1130.
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Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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