Onur Air

Dear Sir/Madam, As Onur Air, we have evaluated your proposed AD as we have three engines affected by this AD (ESN: V10096, V10101 and V10103). As a terminating action sending the engine to shop within 27 months after release of the AD is required, but we believe USI inspections performed iaw IAE SB 72-0594 provides sufficient feedback on the propagation of a crack and no further action is required if no crack propagation is detected. Does not FAA trust the inspections to be sufficient so that 27 months time limit is included. As per our MTBUR none of the above engines are due for shop visit before December 2014 and if we remove these engines around March 2013 (if AD released before end of 2010), apart from SV cost, estimate extra reserve payment for removing 20 months earlier will be 675KUSD (maintenance reserve) + 125KUSD (LLP life), which makes 800KUSD per engine plus the lease engine fee. As this would be a burden to all affected operators that cant be handled easily, we believe either there should be support for this AD or the 27 months time limit should be excluded from the AD. With the time limits in the AD total cost of this AD to Onur Air would be over 4,000,000.00-USD (even not mentioning the shop visit cost + shipment costs + a/c grounding costs).This figure is much above the values determined on the AD. So we believe, as all affected operators and IAE would also agree, engines should be on wing as long as there is no finding in the repeated inspections. Please take this into account in finalizing the AD. We would appreciate your valuable feedback on the issue. Thank you in advance