AD 99-21-26

final rule
Data completeness: 70%

Airworthiness Directives; Raytheon (Beech) Model 400, 400A, 400T, and MU-300-10 Airplanes

AD Number
99-21-26
Status
final_rule
Effective Date
Product Category
aircraft
Docket
96-NM-209-AD
FR Citation
(Federal Register: October 18, 1999 (Volume 64, Number 200))

Applicability

TypeManufacturerModelDetails
aircraft Textron Aviation Inc. 400 Airworthiness Directives; Raytheon (Beech) Model 400, 400A, 400T, and MU-300-10 Airplanes
aircraft Textron Aviation Inc. 400A Airworthiness Directives; Raytheon (Beech) Model 400, 400A, 400T, and MU-300-10 Airplanes
aircraft Textron Aviation Inc. 400T Airworthiness Directives; Raytheon (Beech) Model 400, 400A, 400T, and MU-300-10 Airplanes
aircraft Textron Aviation Inc. MU-300-10 Airworthiness Directives; Raytheon (Beech) Model 400, 400A, 400T, and MU-300-10 Airplanes

Unsafe Condition

Uncommanded nose-down pitch at certain flap settings during icing conditions due to inadequate ice protection system.

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

Required Actions

Revise the Airplane Flight Manual (AFM) to include special operating procedures during icing conditions. Install an additional anti-ice control valve, pressure switch, ice detector, and related components per Raytheon Service Instructions No. T-1A-0064.

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

Raytheon (Beech) Model 400, 400A, 400T, and MU-300-10 airplanes

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

Source: Official FAA Source ↗

Retrieved: Apr 8, 2026

Rights: U.S. Government Public Domain

This site is not affiliated with or endorsed by the FAA. Always verify with official sources.