AIRWORTHINESS DIRECTIVE For the reasons set out in the background section, the CASA delegate whose signature appears below issues the following Airworthiness Directive (AD) under subregulation 39.001(1) of CASR 1998. The AD requires that the action set out in the requirement section (being action that the delegate considers necessary to correct the unsafe condition) be taken in relation to the aircraft or aeronautical product mentioned in the applicability section: (a) in the circumstances mentioned in the requirement section; and (b) in accordance with the instructions set out in the requirement section; and (c) at the time mentioned in the compliance section. Propellers - Variable Pitch - Hartzell AD/PHZL/88 CSE Aviation 6/2007 Applicability: Hartzell Propeller Inc. (formerly TRW Hartzell Propeller) propellers that have a part number (P/N) and serial number (SN) listed in Table 1 of this AD, serviced by Oxford Aviation Limited, doing business as CSE Aviation in the United Kingdom. For propellers listed by SN in Table 1 overhauled or repaired by CSE after November 2003, or overhauled by an approved propeller repair facility after October 2003, do not apply to this AD. Table 1. - Hartzell Propellers by P/N and SN CSE Work Order Number Hartzell Propeller Hartzell Propeller P/N SN Y03516 HC-E2YL-2BSF BG2848 Y03517 HC-E2YL-2BSF BG4112 Y04052 HC-82VL-2C1 942R Y02965 BHC-C2YF-1BF AM2854 Y02778 BHC-C2YF-2CKUF AN1881 Y03382 BHC-C2YF-2CKUF AN1968 Y04132 BHC-C2YF-2CKUF AN2528 Y05097 BHC-C2YF-2CKUF AN3274 Y05048 HC-C2YK-2CUF AN3906 Y05047 HC-C2YK-2CUF AN4033 Y03016 BHC-C2YF-2CKUF AN4271 Y03983 BHC-C2YF-2CLKUF AN4289 Y03166 BHC-C2YF-2CKUF AN5248 Y02607 BHC-C2YF-2CKLUF AN5832 Y04855 BHC-C2YF-2CKLUF AN6857 Y04391 BHC-C2YF-2CKUF AN6981A Y05102 BHC-C2YF-2CLKUF AN6998A Y04709 BHC-C2YF-2CKUF AN7006A Y05070 BHC-C2YF-2CLKUF AN7018A Y03863 BHC-C2YF-CLKUF AN7019A Y04108 BHC-C2YF-2CKUF AN7025A Y03206 BHC-C2YK-2CLKUF AN7168B Y04592 BHC-C2YF-2CKUF AN7071B Y04865 BHC-C2YF-2CLKUF AN7168B Y04846 BHC-C2YF-2CKUF AN7184B Y04808 BHC-C2YF-2CLKUF AN7199B Y03185 BHC-C2YF-2CLKUF AN7209B Y03186 BHC-C2YF-2CKUF AN7215B Y04975 BHC-C2YF-2CKUF AN7249B Y04974 BHC-C2YF-2CLKUF AN7279B Y04818 BHC-C2YF-2CKUF AN7280B Y04532 BHC-C2YF-2CKUF AN7540B Y04561 BHC-C2YF-2CKUF AN7552B Y04638 BHC-C2YF-2CLKUF AN7567B Y04639 BHC-C2YF-2CKUF AN7568B Y04658 BHC-C2YF-2CLKUF AN7581B Y02866 HC-A3VF-2D AT376 Y02867 HC-A3VF-2D AT431 Y04053 HC-C2YK-2CUF AU10008B Y04096 HC-C2YK-2CUF AU10023B Y04143 HC-C2YK-2CUF AU10126B Y04171 HC-C2YK-2CUF AU10139B Y04283 HC-C2YK-2CUF AU10165B Y04274 HC-C2YK-2CUF AU10178B Y04416 HC-C2YK-2CUF AU10401B Y04415 HC-C2YK-2CUF AU10402B Y04478 HC-C2YK-2CUF AU10462B Y04518 HC-C2YK-2CUF AU10541B Y04479 HC-C2YK-2CUF AU10542B Y04563 HC-C2YK-4BF AU10614B Y04564 HC-C2YK-4BF AU10615B Y04560 HC-C2YK-2CUF AU10616B Y04610 HC-C2YK-2CUF AU10696B Y04565 HC-C2YF-2CUF AU10729B Y04566 HC-C2YK-2CUF AU10730B Y04632 HC-C2YK-4BF AU10733B Y04636 HC-C2YK-2CUF AU10771B Y04651 HC-C2YK-4BF AU10790B Y04659 HC-C2YK-2CUF AU10817B Y04681 HC-C2YK-4BF AU10827B Y04701 HC-C2YK-2CUF AU10923B Y04785 HC-C2YK-2CUF AU10952B Y04786 HC-C2YK-2CUF AU11050B Y04736 HC-C2YK-2CUF AU11117B Y04826 HC-C2YK-4BF AU11145B Y04871 HC-C2YK-1BF AU11279B Y04890 HC-C2YK-4BF AU11343B Y05000 HC-C2YK-4CF AU11591B Y05050 HC-C2YK-2CUF AU11731B Y04410 HC-C2YK-2CGUF AU1533 Y04409 HC-C2YK-2CGUF AU1603 Y04344 HC-C2YK-2CLGUF AU2892E Y03377 HC-C2YK-2CGUF AU2955 Y03688 HC-C2YK-2CU AU354 Y02769 HC-C2YK-2CUF AU9013B Y04343 HC-C2YR-2CGUF AU508E Y03110 HC-C2YK-2CUF AU5236 Y04400 HC-C2YK-2CLEUF AU5974E Y04652 HC-C2YK-1B AU6120 Y04321 HC-C2YR-2CLEUF AU6163 Y03200 HC-C2YK-2CUF AU7153E Y03838 HC-C2YK-2CUF AU7357 Y04362 BHC-C2YF-2CLKUF AU7491B Y04219 HC-C2YK-2CLGUF AU7662 Y02598 HC-C2YK-CUF AU8212A Y02770 HC-C2YK-2CUF AU822 Y03482 HC-C2YK-2CUF AU8233A Y03564 HC-C2YK-2CUF AU8299A Y03773 HC-C2YK-2CUF AU8318A Y03674 HC-C2YK-2CUF AU8338A Y02991 HC-C2YK-2CUF AU8339A Y03137 HC-C2YK-2CUF AU8347A Y03018 HC-C2YK-2CUF AU8349A Y02805 HC-C2YK-2CUF AU8354A Y02703 HC-C2YK-2CUF AU8417A Y02664 HC-C2YK-2CUF AU8859A Y04095 HC-C2YK-2CUF AU8923B Y03761 HC-C2YK-CUF AU8968B Y02792 HC-C2YK-2CUF AU9012B Y02848 HC-C2YK-2CUF AU9014B Y03597 HC-C2YK-2CUF AU9015B Y04735 HC-C2YK-2CUF AU9041B Y03229 HC-C2YK-2CGUF AU9135B Y02943 HC-C2YK-2CUF AU9136B Y03197 HC-C2YK-2CUF AU9150B Y04675 HC-C2YK-2CUF AU9182B Y03352 HC-C2YK-2CUF AU9241B Y03354 HC-C2YK-2CUF AU9243B Y03097 HC-C2YK-2CUF AU9246B Y03201 HC-C2YK-2CUF AU9247B Y03686 HC-C2YK-2CUF AU9312B Y03607 HC-C2YK-2CUF AU9332B Y03614 HC-C2YK-2CGUF AU9393B Y03606 HC-C2YK-2CUF AU9394B Y03791 HC-C2YK-2CUF AU9395B Y03866 HC-C2YK-CUF AU9396B Y03888 HC-C2YK-CUF AU9509B Y04948 HC-C2YK-2CUF AU9511B Y03891 HC-C2YK-2CUF AU9518B Y03797 HC-C2YK-2CUF AU9520B Y04001 HC-C2YK-2CGUF AU9593B Y05083 HC-C2YK-2CUF AU9599B Y03694 HC-C2YK-4BF AU9616B Y03696 HC-C2YK-4BF AU9618B Y03695 HC-C2YK-4BF AU9630B Y03620 HC-C2YK-4BF AU9631B Y03627 HC-C2YK-4BF AU9638B Y03625 HC-C2YK-4BF AU9649B Y04047 HC-C2YK-2CUF AU9985B Y04376 HC-C2YL-1BF AX522 Y05051 HC-C2YR-1BF AX527 Y02908 HC-C2YL-1BF AX841B Y04763 HC-C2YL-1BF AX720A Y04731 HC-E2YR-2RBSF BB6694 Y04900 HC-E2YL-2BSF BG2122 Y04738 HC-E2YL-2BSF BG2923 Y04547 HC-E2YL-2BSF BG3219 Y03153 HC-E2YL-2BSF BG3287 Y04061 HC-E2YL-2BSF BG3363 Y04917 HC-E2YL-2BSF BG372 Y04062 HC-E2YL-2BSF BG434 Y04190 HC-E2YL-2BSF BG4344 Y04901 HC-E2YL-2BSF BG4557 Y04737 HC-E2YL-2BSF BG648 Y04898 HC-E2YR 2RBSF BP3287 Y03327 HC-E2YR-2RBS BP5179 Y03680 HC-E2YR-2RBSF BP6199 Y04167 HC-E2YR-2RBSF BP6206 Y03138 HC-E2YR-2RBSF BP6606 Y02709 HC-E2YR-2RBSF BP6838 Y04899 HC-E2YR-2RBSF BP9158 Y03913 HC-E2YR-2RBSF BP9159 Y03139 HC-E2YR-2RBSF BP9168 Y04780 PHC-A3VF-2B BR834 Y02939 HC-B3TN-3DY BUA22056 YO2971 HC-B3TN-3DY BU12462 Y04089 HC-B3TN-3C BU14589 Y03948 HC-BCTN-3B BU16789 Y02767 HC-B3TN-5FL BV3382 Y02768 HC-B3TN-5FL BV3540 Y02946 HC-B3TN-3DY BUA22136 Y03726 HC-B3TN-3G BUA21467 Y03727 HC-B3TN-3G BUA23284 Y03928 HC-B3TN-3D BUA24401 Y04429 HC-B3TN-3N BUA24852 Y04430 HC-B3TN-3N BUA24992 Y05019 HC-B3TN-3G BUA27325 Y03719 HC-B3TN-5E BVA7456 Y03718 HC-B3TN-5E BVA7457 Y04443 HC-B3TN-5FL BVA7770 Y04444 HC-B3TN-5FL BVA7771 Y03304 HC-B4TN-5ML CD1746 Y03165 HC-B4TN-5ML CD1752 Y03164 HC-B4TN-5ML CD1973 Y04535 HC-B4TN-S CDA3529M1 Y04787 HC-B4N-ML CDA3703 Y04788 HC-B4TN-5ML CDA3704 Y03351 HC-B4TN-5ML CDA4424 Y04644 HC-B4TN-5ML CDA4819 Y04534 HC-B4TN-S CDA5047M1 Y04399 HC-C2YK-1BF CH11322 Y03764 HC-C2YK-1BF CH1614B Y02124 HC-C2YK-1BF CH23470 Y02897 HC-C2YK-1BF CH32119A Y04516 HC-C2YK-1BF CH20231 Y04371 HC-C2YK-1BF CH21618 Y04260 HC-C2YK-1BF CH23621 Y02641 HC-C2YK-1BF CH23890(E) Y03969 HC-C2YK-1BF CH25517 Y02648 HC-C2YK-1BF CH26145 Y02896 HC-C2YK-1BF CH32118A Y04244 HC-C2YR-1BF CH27227 Y03763 HC-C2YK-1BF CH27235 Y03704 HC-C2YK-1BF CH28190 Y03141 HC-C2YK-1BF CH29976 Y05015 HC-C2YK-1BF CH30451 Y04153 HC-C2YK-1BF CH32838B Y03949 HC-C2YK-1BF CH32683B Y05124 HC-C2YKR-1BF CH33316B Y03205 HC-C2YK-1BF CH33520B Y03850 HC-C2YK-1BF CH33777B Y03843 HC-C2YK-1BF CH34179B Y04230 HC-C2YK-1BF CH34607B Y04014 HC-C2YR-1BF CH34638B Y05078 HC-C2YK-1BF CH35009B Y04361 HC-C2YK-1BF CH35037B Y04587 HC-C2YK-1BF CH35445B Y04588 HC-C2YK-1BF CH35466B Y05076 HC-C2YK-1BF CH37285B Y05079 HC-C2YK-1BF CH37286B Y05056 HC-C2YK-1BF CH3730B Y04891 HC-C3YR-2LUF CH4488A Y03425 HC-C2YK-1BF CH5073 Y03428 HC-C2YK-1B CH617 Y04126 HC-E2YL-2BTF CJ514 Y03027 HC-C3YR-2UF CK3633A Y02594 HC-C3YR-2UF CK3634A Y03429 HC-C3YR-2UF CK3651A Y03168 HC-C3YR-2UF CK3662A Y03995 HC-C3YR-2UF CK3663A Y03573 HC-C3YR-2UF CK3678A Y03611 HC-C3YR-2UF CK3705A Y03707 HC-C3YR-2UF CK3706A Y03513 HC-E3YR-2UF CK3719A Y03937 HC-C3YR-2UF CK3872A Y03794 HC-C3YR-2UF CK3873A Y03921 HC-C3YR-2UF CK3874A Y04892 HC-C3YR-2UF CK4263A Y03317 HC-C3YR-2UF CK4459A Y02871 HC-C3YR-2UF CK4460A Y02704 HC-C3YR-2UF CK4645A Y03522 HC-C3YR-2UF CK4682A Y04770 HC-F2YR-1F CM535 Y05039 HC-C2YK-4BF DH687E Y04872 HC-E3YR-2ATF DJ10539A Y04873 HC-E3YR-2ALTF DJ10542A Y03975 HC-E3YR-2ALTF DJ10585A Y03974 HC-E3YR-2ATF DJ10832A Y03023 HC-E3YR-2ATF DJ8092A Y03998 HC-E3YR-2ATF DJ8105A Y03997 HC-E3YR-2ATF DJ8106A Y02865 HC-E3YR-2ALTF DJ8128A Y04149 HC-E3YR-2ATF DJ8137A Y04150 HC-E3YR-2ALTF DJ8139A Y04911 HC-E3YR-2ALTF DJ8151A Y02580 HC-E3YR-2ALTF DJ8154A Y04912 HC-E3YR-2ATF DJ8157A Y02864 HC-E3YR-2ATF DJ8161A Y02581 HC-E3YR-2AFT DJ8180A Y04775 HC-E3YR-2ATF DJ8326A Y04774 HC-E3YR-2ALTF DJ8329A Y03760 HC-E3YR-2ATF DJ8872A Y03022 HC-E3YR-2ALTF DJ9503A Y02120 HC-E2YR-1BF DK1068 Y04375 HC-E2YR-1BF DK155 Y03331 HC-E2YR-1BF DK1902B Y04373 HC-E2YR-1BF DK611 Y04168 HC-E2YR-1BF DK620 Y04471 HC-C2YK-1BF DK669 Y03040 HC-C2YK-4BF DN4101A Y03590 HC-C2YK-4BF AU8619A Y03129 HC-C2YK-4BF DN4111A Y03442 HC-C2YK-4BF DN4112A Y03003 HC-C2YK-2CEUF DN4126A Y03630 HC-C2YK-4BF DN4127A Y02620 HC-C2YK-4FC7666A DN4168A Y02680 HC-C2YK-4FC7666A DN4171A Y02786 HC-C2YK-4FC7666A DN4172A Y02619 HC-C2YK-4FC7666A DN4175A Y03588 HC-C2YK-4BF DN4187A Y03116 HC-C2YK-4CF DN4216A Y02679 HC-C2YK-4FC7666A DN4231A Y03209 HC-C2YK-4BF AU9643B Y02677 HC-C2YK-4FC7666A DN4249A Y02667 HC-C2YK-4FC7666A DN4263A Y03253 HC-C2YK-4BF DN4265A Y03592 HC-C2YK-4BF DN4268 Y02796 HC-C2YK-4FC7666A DN4279A Y02788 HC-C2YK-4FC7666A DN4280A Y03210 HC-C2YK-4BF DN4284A Y03212 HC-C2YK-4BF DN4299A Y03574 HC-C2YK-4BF DN9650B Y03260 HC-C2YK-4BF DN4340A Y03254 HC-C2YK-4BF DN4341A Y02665 HC-C2YK-4FC7666A DN4351A Y02681 HC-C2YK-4FC7666A DN4364A Y03208 HC-C2YK-4BF DN4371A Y02787 HC-C2YK-4FC7666A DN4380A Y03621 HC-C2YK-4BF DN4510A Y02666 HC-C2YK-4FC7666A DN4521A Y03589 HC-C2YK-4BF DN4514A Y03619 HC-C2YK-4BF DN4515A Y02678 HC-C2YK-4FC7666A DN4516A Y02618 HC-C2YK-4FC7666A DN4522A Y02615 HC-C2YK-4FC7666A DN4524A Y02614 HC-C2YK-4FC7666A DN4712A Y02616 HC-C2YK-4FC7666A DN4716A Y03439 HC-C2YK-4BF DN4719A Y02662 HC-C2YK-4FC7666A DN4955A Y03626 HC-C2YK-4BF DN4957A Y03252 HC-C2YK-4BF DN4963A Y02668 HC-C2YK-4FC7666A DN4965A Y04191 HC-E2YL-2BLSF DP94 Y02832 HC-C3YR-1RF DY2464A Y04175 PHC-C3YF-2UF EB171 Y04174 PHC-C3YF-2UF EB173 Y03788 PHC-C3YF-2UF EB1977 Y03787 PHC-C3YF-2UF EB1978 Y02779 HC-M2YR-2CEUF FB379 Y04943 PHC-C3YF-1RF EE1354 Y03959 PHC-C3YF-1RF EE1369 Y03754 HC-C2YR-1RF EE227 Y04730 PHC-C3YF-1RF EE2322A Y03767 HC-C3YF-1RF EE351 Y04246 HC-BM5P-3C EVA2226 Y04246 HC-BM5P-3C EVA2246 Y04169 HC-B5MP-3C EVA2281 Y02634 HC-M2YR-2CLEUF FB102 Y02732 HC-M2YR-2CEUF FB1061A Y04252 HC-M2YR-2CEUF FB1064A Y02733 HC-M2YR-2CLEUF FB1066A Y04253 HC-M2YR-2CLEUF FB1067A Y03332 HC-M2YR-2CLEUF FB1177B Y04170 HC-M2YR-2CLEUF FB1196B Y02719 HC-M2YR-2CLEUF FB1167B Y02708 HC-M2YR-2CEUF FB409 Y04492 HC-M2YR-2CEUF FB454 Y03043 HC-M2YR-2CEUF FB99 Y02905 HC-F2YL-2UF FE11 Y02917 HC-F2YL-2UF FE229 Y03753 HC-F2YL-2UF FE282B Y03827 HC-F2YL-2UF FE285B Y03453 HC-F2YL-2UF FE58 Y04876 HC-C3YF-5F FR101 Y04725 HC-C3YF-5F FR185A Y04726 HC-C3YF-5F FR186A Y04829 HC-C3YF-5F FR187A Y04830 HC-C3YF-5F FR188A Y05110 HC-C3YF-5F FR192A Y05111 HC-C3YF-5F FR193A Y04971 HC-C3YF-5F FR206A Y03814 HC-C3YF-5F FR207A Y04878 HC-C3YF-5F FR39 Y03125 HC-C3YF-5F FR206A Y02715 HC-C3YF-5F FR58 Y04448 HC-C3YF-5F FR68 Y02716 HC-C3YF-5F FR72 Y04450 HC-C3YF-5F FR73 Y04569 HC-C3YF-5F FR74 Y04449 HC-C3YF-5F FR78 Y04085 HC-C3YF-5F FR79 Y04970 HC-C3YF-5F FR80 Y02600 HC-C3YF-5F FR82 Y03527 HC-C3YF-5F FR83 Y04877 HC-C3YF-5F FR86 Y04570 HC-C3YF-5F FR87 Y04752 HC-C3YF-5F FR92 Y05008 HC-C3YF-5F FR94 Y03605 HC-B4MP-3B FWA3209 Y03604 HC-B4MP-3B FWA3201 Y03987 HC-B4MP-3A FWA3043 Y03902 HC-B4MP-3A FWA3216 Y03903 HC-B4MP-3A FWA3217 Y04351 HC-B4MP-3A FWA3270 Y03911 HC-B4MP-3A FWA3444 Y03910 HC-B4MP-3A FWA3445 Y03986 HC-B4MP-3A FWA3538 Y04352 HC-B4MP-3A FWA3732 Y04465 HC-B4MP-3A FWA3760 Y04466 HC-B4MP-3A FWA3761 Y03647 HC-A6A-3A GP135 Y03647 HC-A6A-3A GP135 Y02882 HC-A2VK-2 H238 Y02883 HC-A2VK-2 H2472 Y04864 HC-A2YK-2 H392 Y04863 HC-A2YK-2 H396 Y04979 HC-E4N-3G HH1739 Y04980 HC-E4N-3G HH360 Y04977 HC-E4N-3G HH378 Y04978 HC-E4N-3G HH379 Y03667 HC-E4N-3 HH43 Y04125 HC-E4A-3J HJ1050 Y04124 HC-E4A-3J HJ1079 Y04123 HC-E4A-3J HJ1213 Y04874 HC-I3YR-1RF HK127A Y04597 HC-A2VK-1 J1153 Y04783 BHC-C2YF-2CLKUF JS11B Y04687 BHC-C2YF-CLKUF JS70B Y04051 HC-82VL-2C K2624N Requirement: 1. Perform a document search of aeroplane and propeller records to determine if the propeller was involved in a ground strike. 2. Perform the following requirements: (a) Disassemble the propeller. (b) Clean all disassembled propeller parts. (c) Perform a visual inspection for the following conditions: (i) Wear or damage such as cracks, corrosion, scratches, or nicks. (ii) Except for blades installed new at the last CSE maintenance action, examine for: (A) Bent or damaged pitch change knobs. (B) Damage in the bore area of the blade shank. (C) Damage in the blade balance hole. (iii) Damage that indicates a previous ground strike (if applicable). (iv) Unacceptable wear or damage in areas where shot peening is required. It is not necessary to strip the paint and corrosion protective coatings from the external surface of the blade. It is also not necessary to perform dimensional measurements on the external surface of the blade unless there is evidence of damage that has occurred since CSE returned the propeller to service. (v) Confirm that CSE Aviation correctly performed the repairs listed in the manufacturer's maintenance manuals. An example of a maintenance manual repair is chamfering of the hub grease fitting hole on Hartzell "Y'' shank series propellers. (d) Perform all Eddy Current inspections applicable. (e) Repair and replace with serviceable parts, as necessary. (f) Assemble and test. (g) Confirm that hubs affected by AD/PHZL/74 (FAA AD 2001-23-08) are returned to service only on aircraft affected by that AD. Definitions: For the purposes of this AD: (1) Overhauling a propeller is not necessary to comply with the requirements specified in Requirement 2 of this AD. If you do not overhaul the propeller, the TSO does not change. (2) Unacceptable wear is wear or damage that can penetrate the shot peen compressive layer. Note: FAA AD 2006-24-07 Amdt 39-14836 dated 21 November 2006 refers. Compliance: 1. Within 30 days after the effective date of this AD. 2. If the propeller was involved in a ground strike, within 10 flight hours (FH) time-in-service (TIS) after the effective date of this AD, or 2 years after the effective date of this AD, whichever is earlier. For all propellers listed by SN in Table 1 of this AD, not involved in a ground strike, using the compliance schedule detailed in Table 2 of this AD. Table 2. - Compliance Schedule If the time-since-overhaul (TSO) for the propeller on the effective date of this AD is … Then perform the requirements of paragraph (j) or paragraph (k) of this AD within … (1) 1,500 FH TSO or more. 200 FH TIS after the effective date of this AD, but do not exceed 2 years after the effective date of this AD. (2) More than 1,000 FH TSO, but fewer than 1,500 FH TIS. 350 FH TIS after the effective date of this AD, but do not exceed 2 years after the effective date of this AD. (3) 1,000 FH TSO or fewer. 500 FH TIS after the effective date of this AD, but do not exceed 2 years after the effective date of this AD. This Airworthiness Directive becomes effective on 7 June 2007. Background: This AD pertains to certain Hartzell Propeller Inc. HC, BHC, and PHC series propellers serviced by Oxford Aviation Services Limited, doing business as CSE Aviation, in the United Kingdom between September 1998 and October 2003. This AD requires inspecting the propeller blades and other critical propeller parts for wear and mechanical damage. This AD results from findings that CSE Aviation failed to perform some specific inspections and repairs. The issuing of this AD is to detect unsafe conditions that could result in a propeller blade separating from the hub and loss of control of the aeroplane. David Punshon Delegate of the Civil Aviation Safety Authority 27 April 2007