Airworthiness Directive · Amendment 39-17715 · Rolls-Royce Corporation Turbofan Engines
Rolls-Royce Corporation Turbofan Engines
This AD applies to the following Rolls-Royce Corporation (RRC) AE 3007A, A1,A1/1, A1/2, A1/3, A1P, A1E, and A3 turbofan engines:
(1) With an installed high-pressure turbine (HPT) stage 2 wheel, part number (P/N) 23084520, or
(2) With an installed HPT stage 2 wheel, P/N 23069438, 23069592, 23074462, 23074644, or 23075345, except for the HPT stage 2 wheel serial numbers listed in Table 2 through Table 5 of RRC Alert Service Bulletin (ASB) No. AE 3007A-A-72-414, Revision 1, dated December 5, 2012. Those HPT stage 2 wheels maintain their existing approved life limits.
We are superseding airworthiness directive (AD) 2010-19-01 for certain Rolls-Royce Corporation (RRC) AE 3007A series turbofan engines. AD 2010-19-01 required removing certain high-pressure turbine (HPT) stage 2 wheels, or performing inspections on them, and reduced their approved life limits. This new AD clarifies the AE 3007A turbofan engine model applicability, further reduces the approved life limits of affected HPT stage 2 wheels, and eliminates the inspections required by the existing AD. This AD was prompted by additional analysis that concluded that lower life limits for the affected HPT stage 2 wheels are necessary. We are issuing this AD to prevent uncontained failure of the HPT stage 2 wheel, damage to the engine, and damage to the airplane.
(1) For HPT stage 2 wheels, P/N 23069438 and P/N 23069592, do the following:
(i) For HPT stage 2 wheels that have 9,500 cycles since new (CSN) or more on the effective date of this AD, remove the HPT stage 2 wheel from service within 15 cycles-in-service (CIS) after the effective date of this AD.
(ii) After the effective date of this AD, do not approve for return to service any engine with an HPT stage 2 wheel, P/N 23069438 or P/N 23069592, that exceeds the new life limit of 9,500 CSN.
(2) For HPT stage 2 wheels, P/N 23074462, do the following:
(i) For AE 3007A1E turbofan engines with HPT stage 2 wheels installed that have 7,500 CSN or more on the effective date of this AD, and for the AE 3007A, A1, A1/1, A1/2, A1/3, A1P, and A3 turbofan engines with HPT stage 2 wheels installed that have 9,500 CSN or more on the effective date of this AD, remove the wheel from service within 15 CIS after the effective date of this AD.
(ii) Thereafter:
(A) Do not approve for return to service any AE 3007A1E turbofan engine with an HPT stage 2 wheel, P/N 23074462, installed, that exceeds the new life limit of 7,500 CSN; and
(B) Do not approve for return to service any AE 3007A, A1, A1/1, A1/2, A1/3, A1P, and A3 turbofan engines with an HPT stage 2 wheel, P/N 23074462, installed, that exceeds the new life limit of 9,500 CSN.
(C) Throughout the life of the HPT stage 2 wheel, always use the lowest life limit applicable to any engine model in which the part was used in service. If life usage records are not sufficient to identify all engine models in which the part has been flown, the lowest life applicable to any engine model for which the part is eligible must be used.
(3) For HPT stage 2 wheels, P/N 23074644 and P/N 23075345, do the following:
(i) For HPT stage 2 wheels that have 9,500 CSN or more on the effective date of this AD, remove the HPT stage 2 wheel from service within 15 CIS after the effective date of this AD.
(ii) Thereafter, do not approve for return to service any engine with an HPT stage 2 wheel, P/N 23074644 or P/N 23075345, installed, that exceeds the new life limit of 9,500 CSN.
(4) For HPT stage 2 wheels, P/N 23084520, do the following:
(i) For HPT stage 2 wheels that have 23,000 CSN or more on the effective date of this AD, remove the HPT stage 2 wheel from service before the next flight after the effective date of this AD.
(ii) Thereafter, do not approve for return to service any engine with an HPT stage 2 wheel, P/N 23084520, installed, that exceeds the new life limit of 23,000 CSN.
