| AD Number | 64-05-05 | Status | Active |
| Effective Date | February 27, 1964 | Issue Date | Not specified |
| Docket Number | Unknown | Amendment | N/A |
| Product Type | ["Engine"] | Product Subtype | Not specified |
| CFR Part | --- - Part 39 | CFR Section | N/A |
| Citation | This information is not available. | ||
| Manufacturer(s) | Pratt & Whitney Division |
| Model(s) | JT3C-12 JT3C-7 JT3D-1 JT3D-1-MC6 JT3D-1-MC7 JT3D-1A JT3D-1A-MC6 JT3D-1A-MC7 JT3D-3 JT3D-3B JT3D-3C JT3D-5A JT3D-7 JT3D-7A JT4A-10 JT4A-11 JT4A-12 JT4A-3 JT4A-5 JT4A-9 |
64-05-05 PRATT & WHITNEY: Amdt. 691 Part 507 Federal Register February 27, 1964. Applies to All JT3C-7, JT3C-12, and JT3D Series Turbofan Engines, and JT4A Series Turbojet Engines.
Compliance required as indicated.
To preclude severe engine damage as the result of the engine fuel control throttle valve packing leakage, accomplish the following on all Hamilton Standard JFC25 engine fuel controls incorporating aluminum throttle valve assemblies.
(a) For throttle valve assemblies previously overhaul by the procedure described in (d) or engine fuel controls Serial Numbers 34550 and up, overhaul in accordance with (d) at every engine fuel control overhaul.
(b) For throttle valve assemblies previously overhauled with low burnish finish or unknown burnish finish packings P/N's 562026-28 and -29 and with the following new aluminum parts: throttle valve piston, throttle valve rod and throttle valve lower cylinder, overhaul in accordance with (d) as follows:
(1) Overhaul throttle valve assemblies with 2,500 or more hours' time in service since last throttle valve assemblies overhaul or since new, within the next 100 hours' time in service after the effective date of this AD and at every engine fuel control overhaul thereafter.
(2) Overhaul throttle valve assemblies with less than 2,500 hours' time in service since last throttle valve assembly overhaul or since new, prior to the accumulation of 2,600 hours' time in service since last throttle valve assembly overhaul or since new and at every engine fuel control overhaul thereafter.
(c) For throttle valve assemblies previously overhauled with low burnish, unknown burnish finish or high burnish finish packings, P/N's 562026-28 and -29 and any of the following used aluminum parts: throttle valve piston, throttle valve rod and throttle valve lower cylinder, overhaul in accordance with (d) as follows:
(1) Overhaul throttle valve assemblies with 1,100 or more hours' time in service since last throttle valve assemblies overhaul, within the next 100 hours' time in service after the effective date of this AD and every engine fuel control overhaul thereafter.
(2) Overhaul throttle valve assemblies with less than 1,100 hours' time in service since last throttle valve assembly overhaul prior to the accumulation of 1,200 hours' time in service since last throttle valve assembly overhaul and at every engine fuel control overhaul thereafter.
(d) Replace the packings P/N's 562026-28 and -29 with new high burnish finish packings, P/N's 562026-28 and -29. In addition, replace the aluminum throttle valve piston, throttle valve rod, and throttle valve lower cylinder with a new aluminum throttle valve piston, throttle valve rod, and throttle valve lower cylinder. Conduct a complete fuel control calibration after incorporation of the new parts.
(e) Upon the request of the operator an FAA maintenance inspector, subject to prior approval of the Chief, Engineering andManufacturing Branch, FAA Eastern Region, may adjust the repetitive inspection intervals specified in this AD to permit compliance at an established inspection period of the operator if the request contains substantiating data to justify the increase for such operator.
(Pratt & Whitney Aircraft telegraphic messages dated August 5 and 27, and October 30, 1963, to all JT3C-7, JT3C-12, JT3D Series, and JT4A Series operators cover this same subject.)
This directive effective February 27, 1964.