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AD 57-12-03

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Airworthiness directive · Engine Sprag Spindle · Scotts-Bell 47 47J

FAA copy· 21 KB
Download from FAA DRS
AboutSource files 1
Model
47J
Data sheet
TCDS2H1
Registered aircraft
6 matched by model
Product
Aircraft · Rotorcraft

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

57-12-03 BELL: Applies to Model 47J Helicopters Serial Numbers 1420 Through 1426, 1429 Through 1433, 1435 Through 1439, and 1441, 1559, 1562, 1574.

Compliance required prior to July 1, 1957.

In order to preclude the failure of the engine sprag spindle P/N 47-612-167-1, due to overtorquing of the AN 320-10 nut, the following modification must be accomplished.

1. Remove spindle after first removing the 47-612-166 links from the spindle and 47-612-158 brace assemblies.

2. Install one AN 6-17 bolt with one AN 960-616L washer under the head in the spindle.

3. Reinstall the previously removed links on the spindle. Drill a No. 52 (.062 dia.) hole in one castellation of the AN 320-10 nut for safety wire. Reinstall an AN 960-1016 washer and AN 320-10 nut. After positioning links, torque AN 320-10 nut to 150 inch-pounds.

(NOTE: One AN 364-1018 nut may be substituted for the drilled AN 320-10 nut.)

4. Install one AN 960-616L washer and one AN 310-6 nut on end of AN 6-17 bolt. Torque to 160-190 inch-pounds and install one AN 381-3-12 cotter key.

5. Replace spindle. Resafety attach bolts and safety AN 320-10 nut (if used) to the spindle attach bolts.

6. Connect the links, using previously removed hardware.

(Bell Mandatory Service Bulletin No. 120 dated March 29, 1957, covers this same subject.)

Affected TCDS · 1

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

TCDS 2H1Scott's-Bell 47 IncNames 1 of 4 models: 47J

Registered aircraft · 6

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
  • Bell6
By year built
19571958

2 with no year recorded

By model

Aircraft

N2838BBlessed Beginnings Broadcasting Inc · Warsaw, INBuilt 1957 · S/N 1424N2861BScotts Helicopter Service Inc · Le Sueur, MNBuilt 1958 · S/N 1436N2890BBolton Air Co · Niles, MIBuilt 1957 · S/N 1565N2895BA And S Helicopters Inc · Cahokia, ILBuilt 1957 · S/N 1572N8424EWheatley Lester E Jr · Priest River, IDS/N 1802N999YZWheatley Lester E Jr · Priest River, IDS/N 1763