Airworthiness Directive · Amendment 39-17902 · M/r system
AgustaWestland S.p.A. Helicopters
Superseded. A later AD replaced this one: AD 2014-24-02. Comply with the one in force.
This AD applies to the following Agusta Model AB139 and AW139 helicopters, certificated in any category:
(1) For helicopters with Main Rotor (M/R) Rotating Scissors, part number (P/N) 3G6230A00733, with serial numbers (S/Ns) listed in Table 1 of AgustaWestland Bollettino Tecnico No. 139-368, dated March 19, 2014 (BT 139-368), on which the Lower Half Scissors Spherical Bearing (bearing),P/N 3G6230V00654, was not replaced; and
(2) For helicopters with M/R Rotating Scissors, P/N 3G6230A00733, on which the bearing, P/N 3G6230V00654, was replaced with a bearing with a S/N listed in Table 2 of BT 139-368.
We are publishing a new airworthiness directive (AD) for certain AgustaWestland S.p.A. Model AB139 and AW139 helicopters. This AD requires repetitively inspecting the Main Rotor (M/R) Rotating Scissors for play of the Lower Half Scissor Spherical Bearing (bearing) and removing the bearing if there is play beyond allowable limits. This AD also requires removing all affected bearings. This AD is prompted by reports of certain bearings dislodging from certain M/R Rotating Scissors. These actions are intended to detect excessive play of the bearing and prevent failure of the M/R Rotating Scissors and subsequent loss of control of the helicopter.
You are responsible for performing each action required by this AD within the specified compliance time unless it has already been accomplished prior to that time.
(1) Within 5 hours time-in-service (TIS) and thereafter at intervals not to exceed 5 hours TIS, inspect the M/R Rotating Scissors for play of the bearing in accordance with paragraph 4. of Part I, Compliance Instructions, of BT 139-368.
(2) If there is play, before further flight, accomplish a detailed inspection of the M/R Rotating Scissors in accordance with steps 9.1 through 12.9 of AgustaWestland AW139 Document Code 39-C-62-31-00-00A-286C-A, Rotating control installation—Fixed swashplate and rotating scissors—Detailed inspection, issue 001, dated August 6, 2012. If there is play beyond allowable limits, before further flight, remove the bearing.
(3) Within 50 hours TIS, remove any bearing listed in paragraph (a) of this AD.
(4) Prior to installing a M/R Rotating Scissors with a S/N listed in paragraph (a) of this AD, replace the bearing and re-identify the M/R Rotating Scissors in accordance with paragraphs 4.2. through 4.4. of Part II, Compliance Instructions, of BT 139-368.
(5) Do not install a bearing listed in paragraph (a) of this AD into any M/R Rotating Scissors.
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.
