AD 2001-12-21

final rule
Data completeness: 70%

Airworthiness Directives; Boeing Model 747 Series Airplanes

AD Number
2001-12-21
Status
final_rule
Effective Date
Product Category
aircraft
Docket
Docket No. 2000-NM-158-AD
FR Citation
66 FR 33170

Applicability

TypeManufacturerModelDetails
aircraft Boeing 747 Airworthiness Directives; Boeing Model 747 Series Airplanes

Unsafe Condition

Contact between the rotating paddle wheel and the stationary end plates within the center wing tank override/jettison fuel pumps or horizontal stabilizer tank transfer pumps, which could cause sparks and/or a hot surface condition and consequent ignition of fuel vapor in the center wing tank or horizontal stabilizer tank during dry pump operation (no fuel flowing).

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

Required Actions

For certain airplanes, install improved fuel pumps. For all airplanes, revise the Airplane Flight Manual to include procedures to prevent dry operation of the center wing fuel tank override/jettison pumps. For certain airplanes, prohibit operation of the horizontal stabilizer tank transfer pumps in-flight.

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

Compliance Time

Before further flight

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

Affected Aircraft

All Boeing Model 747 series 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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