Discussion \n\n\n\tThe FAA issued AD 2019-12-18, Amendment 39-19673 (84 FR 32028, July 5, 2019) (''AD 2019-12-18''), for Robinson Model R44 II helicopters. AD 2019-12-18 required, for helicopter serial numbers (S/Ns) 14248 through 14268 and 14270 through 14286 and helicopters with a hose part number (P/N) A785-31 installed after April 30, 2018, inspecting the inside of the hose for separation between the outer and inner layers and flexing the hose in all directions while listening for a crinkling sound, which is an indication of separation. If there was any separation or a crinkling sound, AD 2019-12-18 required replacing the hose before further flight. If there was no separation and no crinkling sound, AD 2019-12-18 required replacing the hose within 50 hours time-in-service (TIS). Finally, AD 2019-12-18 prohibited installing hose P/N A785-31 marked with code 1Q18 on any helicopter. \n\tAD 2019-12-18 resulted from 12 reports, including an accident on April4, 2019, of separation between the outer and inner layers of the orange silicone hose out of a suspected population of 100 hoses traced to a specific manufacturing batch marked by code 1Q18 (1st quarter of 2018). The separation of the silicone layers, if not addressed, could result in blockage of air flow to the engine, engine stoppage, and subsequent loss of control of the helicopter. Accordingly, the FAA issued AD 2019-12-18 to address the unsafe condition on these products. \n\nActions Since AD 2019-12-18 Was Issued \n\n\n\tSince the FAA issued AD 2019-12-18, an NTSB report of October 2019 concluded from the accident aircraft's orange silicone hose marked by code 1Q18, that contamination was introduced during the manufacturing process between the silicone layers that prevented a satisfactory bond. \n\tIn addition, a helicopter accident occurred on April 6, 2020, and preliminary investigation indicated that separation between the outer and inner layers of the orange silicone hose P/NA785-31 occurred. This hose was traced to the manufacturing batch marked by code 3Q17 (3rd quarter of 2017). \n\tSubsequently, the FAA determined that any helicopter with an improved black neoprene hose P/N A785-31 installed should not be affected by this AD. The FAA has also determined that, for helicopters with an orange silicone hose, repeating the inspection is necessary. Accordingly, the FAA is superseding AD 2019-12-18 to amend the applicability from all Robinson Model R44 II helicopters to Model R44 II helicopters with an orange silicone hose P/N A785-31 installed. This AD also clarifies that the hose must be removed to perform the inspection, adds a requirement to repeat the inspection, and expands the installation prohibition \n\n((Page 52891)) \n\nto include any orange silicone hose P/N A785-31 marked with code 3Q17 or with an illegible code marking. \n\nComments to AD 2019-12-18 \n\n\n\tAfter AD 2019-12-18 was published, the FAA received a comment from one commenter. \n\nRequest \n\n\n\tAn anonymous commenter requested the FAA clarify which hose P/N A785-31 must be replaced within 50 hours TIS. The commenter stated that, as written, AD 2019-12-18 requires that any hose P/N A785-31 installed after April 30, 2018, must be replaced within 50 hours TIS regardless of its code. The commenter asked whether this is correct, or if instead whether only P/N A785-31 hoses with code 1Q18 need to be replaced. \n\tThe commenter is correct that AD 2019-12-18 required replacement of any hose P/N A785-31 installed after April 30, 2018, regardless of its code. The FAA intended this requirement in the event the manufacturing code becomes illegible during service. However, the FAA agrees that instead only P/N A785-31 hoses marked with code 1Q18 (with no separation and no crinkling sound) must be replaced within 50 hours TIS. The FAA has changed this final rule accordingly. \n\nRelated Service Information \n\n\n\tThe FAA reviewed Robinson Helicopter Company R44 Service Bulletin SB-97, dated April 11, 2019 (SB-97). This service information applies to Robinson Model R44 II helicopters S/Ns 14248 through 14286, except 14269, and to any P/N A785-31 hoses shipped as spares from May through November 2018. This service information specifies, within 1 flight hour or prior to further flight if engine roughness or power loss is, or has been encountered, visually inspecting the hose for separation, flexing the hose to listen for a crinkling sound, which is an indication of separation, and replacing any hose that shows indication of separation. This service information also specifies replacing or discarding all affected hoses by June 30, 2019. \n\tThe FAA also reviewed Robinson Helicopter Company R44 Service Bulletin SB-100, dated July 3, 2019 (SB-100). This service information applies to Robinson Model R44 II helicopters S/Ns 10001 through 14314, except 14269, 14287, 14299, and 14304, and to any P/N A785-31 hoses shipped as spares through March 2019. This service information specifies the same inspection procedures as SB-97, except with a compliance time of within 100 hours TIS or by August 31, 2019, whichever occurs first, and replacing the hose only if there is any indication of separation. This service information also specifies returning the hose to Robinson or discarding a hose with any indication of separation. \n\nFAA's Determination \n\n\n\tThe FAA is issuing this AD after evaluating all the relevant information and determining the unsafe condition described previously is likely to exist or develop in other products of the same type design. \n\nAD Requirements \n\n\n\tThis AD requires: \n\tFor Robinson Model R44 II helicopters with S/Ns 14168 through 14314 inclusive (except S/Ns 14269, 14287, 14299, and 14304), or with an orange silicone hose P/N A785-31 installed after October 1, 2017, and before the effective date of this AD, within 10 hours TIS after the effective date of this AD, inspecting the inside of the hose for separation between the outerand inner layers, and flexing the hose in all directions while listening for a crinkling sound. This inspection must be done with the hose removed. \n\tIf there is any separation or a crinkling sound, removing the hose from service before further flight. \n\tIf there is no separation and no crinkling sound, and the hose is marked with code 3Q17 or 1Q18 or the code marking is illegible, removing the hose from service within 50 hours TIS. \n\tFor all Robinson Model R44 II helicopters with an orange silicone hose P/N A785-31 installed, performing the inspection of the inside of the hose at intervals not to exceed 100 hours TIS or at each annual inspection after the effective date of this AD, whichever occurs first. If there is any separation or a crinkling sound, removing the hose from service before further flight. \n\tThis AD prohibits installing an orange silicone hose P/N A785-31 marked with code 1Q18 or 3Q17, or with an illegible code marking, on any helicopter. \n\tBecause this AD onlyapplies to Model R44 II helicopters with an orange silicone hose P/N A785-31 installed, operators do not have to comply with this AD if they have replaced the orange silicone hose installed on their helicopter with a black neoprene hose P/N A785-31. \n\nDifferences Between This AD and the Service Information \n\n\n\tSB-97 and SB-100 apply to Robinson Model R44 II helicopters with certain S/Ns and certain spare hoses. This AD applies to Robinson Model R44 II helicopters with an orange silicone hose P/N A785-31 installed instead. SB-97 specifies inspecting the hose within one flight hour or prior to further flight if engine roughness or power loss has been encountered, and SB-100 specifies inspecting the hose within 100 hours TIS or by August 31, 2019, whichever occurs first. For certain helicopters, this AD requires inspecting the hose within 10 hours TIS, and for all other helicopters, within 100 hours TIS or at the next annual inspection, whichever occurs first. This AD requires repeating the inspection, whereas SB-97 and SB-100 do not. SB-97 specifies replacing all affected hoses, even if they pass the inspection, by June 30, 2019, and SB-100 specifies only replacing a hose if the hose has any indication of separation. This AD requires removing from service all hoses with any separation or a crinkling sound, as well as hoses marked with code 3Q17, 1Q18, or an illegible code, even if they pass the inspection. \n\nFAA's Justification and Determination of the Effective Date \n\n\n\tSection 553(b)(3)(B) of the Administrative Procedure Act (5 U.S.C.) authorizes agencies to dispense with notice and comment procedures for rules when the agency, for ''good cause'' finds that those procedures are ''impracticable, unnecessary, or contrary to the public interest.'' Under this section, an agency, upon finding good cause, may issue a final rule without seeking comment prior to the rulemaking. \n\tAn unsafe condition exists that requires the immediate adoption of this AD without providing an opportunity for public comments prior to adoption. The FAA has found that the risk to the flying public justifies waiving notice and comment prior to adoption of this rule because the corrective actions must be completed within 10 hours TIS and within 100 hours TIS, a time period of up to four months based on the average flight-hour utilization rates of these helicopters. Therefore, notice and opportunity for prior public comment are impracticable and contrary to public interest pursuant to 5 U.S.C. 553(b)(3)(B). In addition, for the reasons stated above, the FAA finds that good cause exists pursuant to 5 U.S.C. 553(d) for making this amendment effective in less than 30 days. \n\nComments Invited \n\n\n\tThis AD is a final rule that involves requirements affecting flight safety, and the FAA did not provide you with notice and an opportunity to provide your comments prior to it becoming \n\n((Page 52892)) \n\neffective. However, the FAA invites you to participate in this rulemaking by submitting written comments, data, or views. The most helpful comments reference a specific portion of the AD, explain the reason for any recommended change, and include supporting data. To ensure the docket does not contain duplicate comments, commenters should send only one copy of written comments, or if comments are filed electronically, commenters should submit them only one time. \n\tExcept for Confidential Business Information (CBI) as described in the following paragraph, and other information as described in 14 CFR 11.35, the FAA will file in the docket all comments received, as well as a report summarizing each substantive public contact with FAA personnel concerning this rulemaking during the comment period. The FAA will consider all the comments received and may conduct additional rulemaking based on those comments. \n\nConfidential Business Information \n\n\n\tConfidential Business Information (CBI) is commercial or financial information that is both customarily and actually treated as private by its owner. Under the Freedom of Information Act (FOIA) (5 U.S.C. 552), CBI is exempt from public disclosure. If your comments responsive to this final rule contain commercial or financial information that is customarily treated as private, that you actually treat as private, and that is relevant or responsive to this final rule, it is important that you clearly designate the submitted comments as CBI. Please mark each page of your submission containing CBI as ''PROPIN.'' The FAA will treat such marked submissions as confidential under the FOIA, and they will not be placed in the public docket of this final rule. Submissions containing CBI should be sent to Roger Gretler, Aerospace Engineer, Los Angeles ACO Branch, Compliance & Airworthiness Division, FAA, 3960 Paramount Blvd., Lakewood, CA 90712; phone 562-627-5251; email roger.gretler@faa.gov. Any commentary that the FAA receives which is not specifically designated as CBI will be placed in the publicdocket for this rulemaking. \n\nRegulatory Flexibility Act \n\n\n\tThe requirements of the Regulatory Flexibility Act (RFA) do not apply when an agency finds good cause pursuant to 5 U.S.C. 553 to adopt a rule without prior notice and comment. Because the FAA has determined that it has good cause to adopt this rule without notice and comment, RFA analysis is not required. \n\nCosts of Compliance \n\n\n\tThe FAA estimates that this AD affects up to 187 helicopters of U.S. registry. Labor rates are estimated at $85 per work-hour. Based on these numbers, the FAA estimates the following costs to comply with this AD. \n\tInspecting a hose takes about 0.5 work-hour for an estimated cost of $43 per helicopter and $8,041 for the U.S. fleet per inspection cycle. Replacing a hose takes about 0.5 work-hour and parts cost about $151 for an estimated cost of $194 per helicopter. \n\nAuthority for This Rulemaking \n\n\n\tTitle 49 of the United States Code specifies the FAA's authority to issue rules onaviation safety. Subtitle I, Section 106, describes the authority of the FAA Administrator. Subtitle VII, Aviation Programs, describes in more detail the scope of the Agency's authority. \n\tThe FAA is issuing this rulemaking under the authority described in Subtitle VII, Part A, Subpart III, Section 44701, General requirements. Under that section, Congress charges the FAA with promoting safe flight of civil aircraft in air commerce by prescribing regulations for practices, methods, and procedures the Administrator finds necessary for safety in air commerce. This regulation is within the scope of that authority because it addresses an unsafe condition that is likely to exist or develop on products identified in this rulemaking action. \n\nRegulatory Findings \n\n\n\tThis AD will not have federalism implications under Executive Order 13132. This AD will not have a substantial direct effect on the States, on the relationship between the national government and the States, or on the distribution of power and responsibilities among the various levels of government. \n\tFor the reasons discussed above, I certify that this AD: \n\t(1) Is not a ''significant regulatory action'' under Executive Order 12866, and \n\t(2) Will not affect intrastate aviation in Alaska. \n\nList of Subjects in 14 CFR Part 39 \n\n\n\tAir transportation, Aircraft, Aviation safety, Incorporation by reference, Safety.