AD 69-18-02

Airworthiness directive · Internal Splines · Rolls-Royce 250-C10 (T63-A-5), 250-C10B (T63-A-5A), 250-C10D (T63-A-700) and 4 more

Effective
September 3, 1969
Models
250-C10 (T63-A-5), 250-C10B (T63-A-5A), 250-C10D (T63-A-700), 250-C18, 250-C18A, 250-C18B, 250-C18C
Data sheet
TCDSE4CE
Registered aircraft
105 matched by model
Product
Engine
Amendment
39-831

Unofficial copy of the text in the FAA’s Dynamic Regulatory System. The FAA’s own copy is the authoritative one. DRS record last changed May 30, 2024.

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The airworthiness directive

69-18-02 ALLISON: Amdt. 39-831. Applies to Models 250-C10 and 250-C18 Series Engines.

Compliance: Unless already accomplished, within the next 50 hours' time in service after the effective date of this AD, on all engines having 750 or more hours' time in service since new or last overhaul, or at or before 800 hours' time in service on engines that have less than 750 hours' time in service since new or last overhaul at the effective date of this AD, accomplish the following:

To detect excessive wear of the internal splines:

A) Inspect the internal spline on the P/N 6840847 helical power train drive gear using an Allison P/N EX 83339 plug gage. If this gage enters the spline, replace the gear with a new or serviceable part prior to returning the engine to service. Allison Commercial Service Letter No. 250 CSL-35, dated August 15, 1969, pertains to this inspection.

B) When the engine is modified in accordance with Allison Commercial Engine Bulletin No. 250 CEB-61, dated July 25, 1969, the inspections required by Paragraph A of this AD will no longer be required. Gear boxes having Serial Numbers ending in the suffix "B" incorporate Commercial Engine Bulletin No. 250 CEB-61.

This amendment becomes effective September 3, 1969.

Affected TCDS · 1

The type certificate data sheets for the models this AD names, matched by model and maker.

Registered aircraft · 105

Registered aircraft whose airframe or engine model this AD names. Matched by model only, so check each against the AD’s applicability.

By aircraft maker
  • Bell38 aircraft
  • Hughes17 aircraft
  • Hiller15 aircraft
  • Enstrom Helicopter9 aircraft
  • Cessna7 aircraft
  • Other makers1219 aircraft
By year built
19602005
Registered aircraft by year built: 97 aircraft
19601
19624
19642
19652
19665
19673
196811
19696
19701
19725
19731
19741
19765
19772
19782
19791
19804
19815
19821
19841
19851
19861
19881
19922
19942
19967
19974
19982
19992
20006
20023
20042
20051

8 with no year recorded

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Aircraft

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