Airworthiness Directive · Amendment 39-11655 · Empresa Brasileira de Aeronautica, S.A. (EMBRAER), Model EMB-145 Series Airplanes
Empresa Brasileira de Aeronautica, S.A. (EMBRAER), Model EMB-145 Series Airplanes
All Model EMB-145 series airplanes, serial numbers 145004 through 145103 inclusive, 145105, and 145106; certificated in any category.
Note 1: This AD applies to each airplane identified in the preceding applicability provision, regardless of whether it has been modified, altered, or repaired in the area subject to the requirements of this AD. For airplanes that have been modified, altered, or repaired so that the performance of the requirements of this AD is affected, the owner/operator must request approval for an alternative method of compliance in accordance with paragraph (d) of this AD. The request should include an assessment of the effect of the modification, alteration, or repair on the unsafe condition addressed by this AD; and, if the unsafe condition has not been eliminated, the request should include specific proposed actions to address it.
This amendment supersedes an existing airworthiness directive (AD), applicable to all Empresa Brasileira de Aeronautica, S.A. (EMBRAER), Model EMB-145 series airplanes, that currently requires repetitive emergency extension (free-fall) functional tests of the nose landing gear (NLG), and lubrication of all NLG hinge points, to ensure that the NLG extends and locks down properly; and corrective action, if necessary. This amendment also requires a terminating modification that includes replacement of the NLG door solenoid valve with an improved valve; replacement of the landing gear (LG) safety pins holder with an improved holder; and replacement of the NLG maneuvering actuator with an improved actuator. This amendment also limits the applicability of the existing AD. This amendment is prompted by issuance of mandatory continuing airworthiness information by a foreign civil airworthiness authority. The actions specified by this AD are intended to prevent failure of the NLG to extend and lock down properly, which could result in damage to the airplane structure, and consequent reduced controllability of the airplane upon landing.
Required as indicated, unless accomplished previously.
To prevent failure of the nose landing gear (NLG) to extend and lock down properly, which could result in damage to the airplane structure, and consequent reduced controllability of the airplane upon landing, accomplish the following:
(a) Within 50 flight hours after July 9, 1998 (the effective date of AD 98-13-34, amendment 39-10625), perform an emergency extension (free-fall) functional test of the NLG, to ensure that the mechanism extends and locks down properly, in accordance with EMBRAER Alert Service Bulletin 145-32-A029, dated April 15, 1998. Repeat the functional test and lubrication procedures thereafter at intervals not to exceed every “A” check, but no later than 400 flight cycles.
Note 2: The alert service bulletin references EMBRAER Aircraft Maintenance Manual (AMM), Chapter 32-34-00, as an additional source of service information for accomplishment of the emergency extension functional test.
(1) If the extension time of the landing gear is within 30 seconds, prior to further flight, lubricate all NLG hinge points in accordance with Figure 1 of the Accomplishment Instructions of the alert service bulletin.
(2) If the extension time of the landing gear exceeds 30 seconds, prior to further flight, accomplish the requirements of paragraphs (a)(2)(i) and (a)(2)(ii) of this AD.
(i) Lubricate all NLG hinge points in accordance with Figure 1 of the Accomplishment Instructions of the alert service bulletin. And
(ii) Perform a normal system functional test of the NLG for five cycles, and repeat the emergency extension functional test specified by paragraph (a) of this AD. If the extension and locking time still exceeds 30 seconds, prior to further flight, repair in accordance with a method approved by either the Manager, Atlanta Aircraft Certification Office (ACO), FAA, Small Airplane Directorate, or the Departmento de Aviacao Civil (DAC) (or its delegated agent).
Note 3: The alert service bulletin references EMBRAER AMM, Chapter 32-30-00, as an additional source of service information for accomplishment of the normal system functional test.
(3) If any malfunction other than that specified in paragraph (a)(2) of this AD is detected, prior to further flight, repair in accordance with a method approved by the Manager, Atlanta ACO, or the DAC (or its delegated agent).
(b) Within 2,000 flight hours after the effective date of this AD, accomplish paragraphs (b)(1) and (b)(2) of this AD. Accomplishment of paragraphs (b)(1) and (b)(2) of this AD constitutes terminating action for the requirements of paragraph (a) of this AD.
(1) Replace the nose landing gear door solenoid valve, part number (P/N) 2225-0100-001, with a new valve, P/N 2225-0100-003; and replace the landing gear (LG) safety pins holder, P/N 145-27571-001, with a new holder, P/N 145-37912-001; in accordance with EMBRAER Service Bulletin 145-32-0036, dated February 1, 1999.
(2) Replace the nose landing gear maneuvering actuator, P/N 1300B0000-01, with a new actuator, P/N 1300B0000-02, in accordance with EMBRAER Service Bulletin 145-32-0037, dated February 12, 1999.
(c) As of the effective date of this AD, no person shall install a nose landing gear door solenoid valve, P/N 2225-0100-001, a landing gear safety pins holder, P/N 145-27571-001, or a nose landing gear maneuvering actuator P/N 1300B0000-01, on any airplane.
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.
Aircraft
