Back to AD

AD 57-07-01 ACTIVE

Elevator Inspection and Rework
Key Information
AD Number 57-07-01 Status Active
Effective Date Not specified Issue Date Not specified
Docket Number Unknown Amendment N/A
Product Type ["Aircraft"] Product Subtype ["Rotorcraft"]
CFR Part --- - Part 39 CFR Section N/A
Citation This information is not available.
Applicability
Manufacturer(s) Scotts-Bell 47 Inc
Model(s) 47H-1
Regulatory Text

57-07-01 BELL: Applies to All Model 47H1 Helicopters Serial Numbers 1347 Through 1349, 1351 Through 1360, and 1362 Through 1371.

Compliance required as indicated.

Due to reported looseness of synchronized elevator assemblies and cracking of elevator shafts, the following daily inspection and rework are required:

1. Daily Inspection: In order to determine that looseness of the elevator assembly is not excessive, the following inspection must be conducted daily until rework, item 2 is accomplished:

(a) Hold end of elevator and move gently in vertical and horizontal directions (both sides) to check for looseness. Looseness may be in the four rivets that secure the shoulder fittings to the elevator shaft, between the shoulder fittings and the elevator shaft, or in the bolts and tapered bushing securing the two sections of the elevator at the elevator splice coupling.

(b) If looseness is found, the elevator assembly should be removed so that the rework and additional inspections of item 2 be accomplished.

2. Rework or replacement of loose or cracked elevator assemblies must be completed prior to the next flight.

(a) Inspect elevator shafts at tapered bushing holes for cracks or hole elongation. Remove rivets which attach shoulder fittings, P/N 47-267-404-3, to elevator shaft and to inboard elevator rib. Slide shoulder fittings away from ribs and inspect elevator shafts and shoulder fittings with a 10-power glass for cracks or rivet hole elongation.

(b) If shafts are cracked, replace the elevator assembly.

(c) If shoulder fittings are cracked, replace the shoulder fittings.

(d) If no cracks are found, remove burrs from holes and rework elevator shafts in accordance with Bell Service Bulletin No. 117.

This bulletin describes in detail the procedure for removing existing filler plugs from elevator shafts, inserting new plugs, P/N 47-267-420-5, attaching shoulder fittings to the elevator ribs and shafts, installing and securing a spring pin, P/N MS171600, reassembling splice coupling, P/N 47-267-433-1, reassembling elevator assemblies with two additional AN 173-20A bolts and the four 79B1-3-4 tapered bushings previously removed. If the tapered bushing holes are elongated, four 79B1-3-5 tapered bushings must be used in place of the -4 tapered bushings removed.

(Bell Service Bulletin No. 117 covers this same subject.)