Docket No: FAA-2015-0839 

Directorate ID: 2015-CE-006 

Disposition Comments 

Originating Office Tracking No.: ~0 /SCDo! 

Next Step: ~FRAN 0 SNPRM 

0 These comments are in 

response to an SNPRM 

0 No Comments/Only Supportive Comments Received - ({this box is checked, no signatures are 

required 

Has the referenced service information been revised since the NPRM was issued? 

If yes, list latest revision and attach a copy. Note that changes beyond the scope ofthe 

previously published NPRMwill require a new notice. Contact/he Directoratefocal point 

for guidance. I .ate-;! RL'\ i -; ion. 

Instructions: Summarize all comments by issue (not by commenter) and provide your recommended resolution of 

each issue. All comments relating to the same issue should be discussed together. Do not list all of the issues 

from one commenter together. If changes to the AD are required based on the comments received, explain why and 

describe in detail what change(s) you recommend. Reference FAA-IR-M-8040.1 C Chapter 9. 

ISSUE 1: Select one of the following: compliance time 

If other, explain: 

Commenter(s): William West 

What change to the AD action is requested? Requests allowance in compliance time a " I 0% extension of 

time to work the actions in with already scheduled maintenance''. 

Why is the change requested or how is it justified? This flexibility, as stated above, was given in AD 

2000-01-16 that involves the exhaust systems on these same airplanes. An extra 20 hours of operation 

before compliance is not expected to cause additional risk. 

Do we agree? No 

If YES, we agree because Jnsertju"lilicntinn Make the following changes to the AD: I i~t ,Illy 

changes to the .t\D 

If PARTIALLY AGREE, we agree with Insert ll...,l because IIJ"crtju"ti1ic.lllllll We disagree with 

Insert text because lnscnju"tilicatinn Make the following changes to the AD: I is! <111\ 

changes t~) th~.: :\D 

If NO, we don't agree because AD 2015-07-03 was an immediately adopted rule (JAR). Thus, it was 

published prior to the Comment Period. Such an extension can be requested with an alternate method 

of compliance (AMOC), as discussed in the AD. A supersedure AD would not be considered as a 

result of this comment. 

ISSUE 2: Select one of the following: costs 

If other, explain: and inspections are excessive 

Commenter(s): Cape Air I Nantucket Airl ines 

What change to the AD action is requested? Recurrent eddy current of forward engine beam area are 

unnecessary based on actual experience. They are recommending lighted borescope and X-ray 

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inspections, by appropriately qualified inspectors, at repeat inspections of 500 flight hours for airplanes 

with 30,000 flight hours or more; 750, for 25,000 to 29,999; I 000, for 20,000 to 24,999; 2500 for 15,000 

to 19,999 until the engine mount beam is replaced. In a subsequent comment letter, they propose to 

address the excessively frequent inspections, and request an extension to the Comment Period until July 

I 0. This will allow them time to complete their fatigue and damage tolerance analysis. They have 

contracted a Designated Engineering Representative (DER) firm with experience in Cessna 402C/4 14A 

structure to do the analysis. They have committed to providing aircraft, financial, and other required 

resources to validate this analysis with direct comparison to actua l fatigue stresses. They will share this 

information with Cessna and the Wichita Aircraft Certification Office (ACO) to be used to revise Cessna 

MEL-54-01 and AD 201 5-07-03. 

Why is the change requested or how is it justified? They have found no defects using eddy current. The 

repetitive compliance times do not positively contribute to overall aircraft inspection program and their 

operational safety profile. These inspection intervals may be a hindrance to safety. The 200 hour repeat 

inspections will cost them $593,670.00 annua lly plus other operational costs including flight crew, 

aircraft reposition, and aircraft out of service time. In addition, they estimate $8,500.00 in parts per beam 

and 55 hours per beam in labor. At $85.00 per labor hour, each engine mount beam replace cost would be 

$ 13,175.00 or $52,700.00 per airplane. For them, this represents $4,374, I 00.00 for their fleet of 

airplanes. They stated that Cessna says that they have no repair other than beam replacement, and Cessna 

does not plan to develop a repair. Because of Cessna inaction in developing repair options that the true 

cost to replace the engine mounts beams needs to be discussed to understand the actual financial impact. 

Do we agree? No 

If YES, we agree because Insert ju~tilicali~ll1 Make the following changes to the AD: Li·•l am 

changes to the A I) 

If PARTIALLY AGREE, we agree with Insert tc:-.l because Insert juslilic<~liPn We disagree with 

Insert lc'\l because Insert justitic·ltll)ll Make the following changes to the AD: f j,t ;HI) 

chan gc~ to th ... · 1\ L) 

If NO, we don't agree because AD 2015-07-03 was an immediately adopted rule (JAR). Thus, it was 

published prior to the Comment Period. However, fwther study, such as their proposed analysis 

initiative, may result in future action. The Comment Period cannot be changed to July I 0 since the 30 

day Comment Period is a requirement per FAA Order FAA-IR-M-8040.1 C. However, we will place 

any late comments in Federal Docket Management System (FDMS). We will consider their late 

comments in the event that a supersedure AD is considered. 

For additional issues, double-click here 

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Signatur·e Section 

Signature indicates concurrence with this action. 

Originating Office Tracking No.: 

Date 

Date 

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