Airworthiness Directive · Amendment 39-15431 · Honeywell International Inc. ATF3-6 and ATF3-6A Series Turbofan Engines
Honeywell International Inc. ATF3-6 and ATF3-6A Series Turbofan Engines
This AD applies to Honeywell International Inc. ATF3-6-4C, ATF3-6A-3C, and ATF3-6A-4C turbofan engines equipped with part number (P/N) 3002070-1 low pressure compressor (LPC) Aft shaft. These engines are installed on, but not limited to, Dassault Aviation Fan Jet Falcon Series G (Falcon 20G/HU25), and Dassault Aviation Mystere-Falcon 200 airplanes.
The FAA is adopting a new airworthiness directive (AD) for Honeywell International Inc. ATF3-6 and ATF3-6A series turbofan engines equipped with a certain part number (P/N) low pressure compressor (LPC) aft shaft. This AD requires removing from service those LPC aft shafts and installing a serviceable LPC aft shaft. This AD results from reports of eight LPC aft shafts found cracked during fluorescent penetrant inspection (FPI). We are issuing this AD to prevent uncoupling and overspeed of the low pressure turbine, which could result in uncontained engine failure and damage to the airplane.
You are responsible for having the actions required by this AD performed within the compliance times specified in Table 1 and Table 2 of this AD, unless the actions have already been done.
| For ATF3-6A-4C turbofan engines, if the cycles-since-new (CSN) on the effective date of this AD are: | Then replace the LPC Aft shaft: |
|---|---|
| (1) 6,500 or more CSN | Within an additional 100 cycles-in-service (CIS). |
| (2) 5,000 to 6,499 CSN | Within an additional 800 CIS, but not more than 6,600 CSN, whichever occurs first. |
| (3) 4,000 to 4,999 CSN | Within an additional 1,500 CIS, but not more than 5,800 CSN, whichever occurs first. |
| (4) Fewer than 4,000 CSN | Within an additional 2,000 CIS, but not more than 5,500 CSN, whichever occurs first. |
| For ATF3-6-4C and ATF3-6A-3C turbofan engines, if the CSN on the effective date of this AD are: | Then replace the LPC Aft shaft: |
|---|---|
| (1) 4,400 or more CSN | Within an additional 100 CIS. |
| (2) 3,600 to 4,399 CSN | Within an additional 500 CIS, but not more than 4,500 CSN, whichever occurs first. |
| (3) 3,300 to 3,599 CSN | Within an additional 700 CIS, but not more than 4,100 CSN, whichever occurs first. |
| (4) Fewer than 3,300 CSN | Within an additional 1,000 CIS, but not more than 4,000 CSN, whichever occurs first. |
Using the compliance schedule in Table 1 or Table 2 of this AD as applicable, remove the LPC aft shaft, P/N 3002070-1, from service, and install a serviceable LPC aft shaft.
For the purpose of this AD, a serviceable LPC aft shaft is an aft shaft with a P/N not referenced in this AD.
The aircraft, engines and makers this AD names, by the model designations in its text. A model listed here may still be outside the AD's serial ranges.
Engines
