Airworthiness Directive · Amendment 39-22945 · Reciprocating engine cylinder section
Austro Engine GmbH Engines
This AD applies to Austro Engine GmbH Model E4 and E4P engines with an engine serial number (ESN) listed in Tables 1, 2, 3, and 4 of Austro Engine GmbH Mandatory Service Bulletin No. MSB-E4-039/3, Revision 3, dated November 22, 2023 (Austro MSB-E4-039/3).
The FAA is superseding Airworthiness Directive (AD) 2023-20-03 for certain Austro Engine GmbH Model E4 and E4P engines. AD 2023-20-03 required repetitive engine oil analysis for aluminum content outside the acceptable limits and, if necessary, replacement of the pistons, piston rings, con-rods assembly, and crankcase or, as an alternative, replacement of the engine core. Since the FAA issued AD 2023-20-03, the manufacturer identified errors in the lists of affected engines and provided updated information, which prompted this AD. This AD retains the requirements of AD 2023-20-03, adds compliance times for additional affected engine serial numbers, and removes certain engine serial numbers from the applicability of the existing AD. The FAA is issuing this AD to address the unsafe condition on these products.
(1) For all affected engines, within the applicable compliance times specified in table 1 to paragraph (g)(1) of this AD, perform an oil analysis in accordance with paragraph 2., Technical Details, Engine Oil Analysis of Austro MSB-E4-039/3, and do not return the engine to service until the results of the oil analysis have been determined.
| Engine group | Compliance time | Interval |
|---|---|---|
| Group 1 and Group 3 engines that do not have an ESN identified in table 2 to paragraph (g)(1) of this AD | Within 15 flight hours (FHs) from December 11, 2023 (the effective date of AD 2023-20-03) | Before exceeding 50 FHs since last oil analysis. |
| Group 1 and Group 3 engines that have an ESN identified in table 2 to paragraph (g)(1) of this AD | Within 15 FHs from the effective date of this AD | Before exceeding 50 FHs since last oil analysis. |
| Group 2 and Group 4 engines that do not have an ESN identified in table 2 to paragraph (g)(1) of this AD | Within 25 FHs from December 11, 2023 (the effective date of AD 2023-20-03) | Before exceeding 100 FHs since last oil analysis. |
| Group 2 and Group 4 engines that have an ESN identified in table 2 to paragraph (g)(1) of this AD | Within 25 FHs from the effective date of this AD | Before exceeding 100 FHs since last oil analysis. |
| Engine group | ESN | ESN | ESN | ESN |
|---|---|---|---|---|
| Group 1 | E4-A-06367 | E4-A-06248 | ||
| Group 2 | E4-C-06249 | E4P-C-06185 | ||
| Group 3 | E4-A-05072 | E4-A-05074 | E4-A-05075 | E4-A-05078 |
| Group 3 | E4-A-05079 | E4-A-05080 | E4-A-05081 | E4-A-05082 |
| Group 3 | E4-A-05083 | E4-A-05084 | E4-A-05085 | E4-A-05086 |
| Group 3 | E4-A-05087 | |||
| Group 4 | E4-C-00559 | E4-C-05089 | E4-C-05090 | E4-C-05091 |
| Group 4 | E4-C-05092 | E4-C-05093 | E4-C-05094 | E4-C-05096 |
| Group 4 | E4-C-05098 | E4-C-05099 | E4-C-05100 | E4-C-05101 |
| Group 4 | E4-C-05102 | E4-C-05103 | E4-C-05104 | E4-C-05105 |
| Group 4 | E4-C-05106 | E4-C-05107 | E4-C-05108 | E4-C-05109 |
| Group 4 | E4-C-05110 | E4-C-05111 | E4P-C-06073 |
(2) Thereafter, repeat the oil analysis required by paragraph (g)(1) of this AD before exceeding the applicable interval specified in table 1 to paragraph (g)(1) of this AD.
(3) Following each repetitive oil analysis, the engine may be returned to service for no more than the applicable interval specified in table 1 to paragraph (g)(1) of this AD, until receipt of the oil analysis result.
(4) If the result of any oil analysis required by paragraph (g)(1) of this AD indicates the aluminum content of the oil is greater than the limit specified in paragraph 2., Technical Details, Engine Oil Analysis, Table 5—Oil check analysis Aluminum PPM allowable; of Austro MSB-E4-039/3, before further flight, replace the pistons, piston rings, con-rods assembly, and crankcase, or replace the engine core in accordance with paragraph 2., Technical Details, Engine core replacement; or Pistons, piston rings, crankcase and con-rod assy replacement; as applicable, of Austro MSB-E4-039/3.
(5) For Group 3 and Group 4 engines, within the applicable compliance times specified in table 3 to paragraph (g)(5) of this AD, replace the pistons, piston rings, and con-rods assembly, or replace the engine core in accordance with paragraph 2., Technical Details, Engine core replacement; or Pistons, piston rings and con-rod assy replacement, as applicable, of Austro MSB-E4-039/3.
| Engine group | Compliance time |
|---|---|
| Group 3 engines that do not have an ESN identified in table 2 to paragraph (g)(1) of this AD | Before exceeding 900 FHs since new, or within 15 FHs after December 11, 2023 (the effective date of AD 2023-20-03), whichever occurs later. |
| Group 3 engines that have an ESN identified in table 2 to paragraph (g)(1) of this AD | Before exceeding 900 FHs since new, or within 15 FHs after the effective date of this AD, whichever occurs later. |
| Group 4 engines that do not have an ESN identified in table 2 to paragraph (g)(1) of this AD | Before exceeding 1,000 FHs since new, or within 25 FHs after December 11, 2023 (the effective date of AD 2023-20-03), whichever occurs later. |
| Group 4 engines that have an ESN identified in table 2 to paragraph (g)(1) of this AD | Before exceeding 1,000 FHs since new, or within 25 FHs after the effective date of this AD, whichever occurs later. |
Note 1 to paragraph (g)(5): FHs since new indicated in table 3 to paragraph (g)(5) of this AD are FHs accumulated by the engine since first installation on an airplane or since last overhaul as of December 11, 2023 (the effective date of AD 2023-20-03) for Group 3 and 4 engines that do not have an ESN identified in table 2 to paragraph (g)(1) of this AD, or as of the effective date of this AD for Group 3 and 4 engines that have an ESN identified in table 2 to paragraph (g)(1) of this AD.
(1) Replacement of the pistons, piston rings, con-rods assembly, and crankcase, or replacement of the engine core, as specified in paragraph (g)(4) of this AD, constitutes terminating action for the repetitive oil analysis required by paragraph (g)(2) of this AD.
(2) Replacement of the pistons, piston rings, and con-rods assembly, or replacement of the engine core, as specified in paragraph (g)(5) of this AD, constitutes terminating action for the repetitive oil analysis required by paragraph (g)(2) of this AD.
For the purpose of this AD:
(1) Group 1 engines are engines having an ESN listed in Table 1 of Austro MSB-E4-039/3.
(2) Group 2 engines are engines having an ESN listed in Table 2 of Austro MSB-E4-039/3 MSB-E4-039/3.
(3) Group 3 engines are engines having an ESN listed in Table 3 of Austro MSB-E4-039/3.
(4) Group 4 engines are engines having an ESN listed in Table 4 of Austro MSB-E4-039/3.
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.
