1400 North Hurstbourne Pkwy Louisville, KY 40223 502.329.3000 Tel November IO, 20I5

Federal Aviation Administration C/0 U.S. Department ofTransportation Docket Operations, M-30 West Building Ground Floor Room Wl2-I40 I200 New Jersey Avenue SE Washington, DC 20590 SUBJECT: Notice ofProposedRule Making (NPRM) 20I4-NM-2I9-AD; Docket No. FAA-20I5- 3637 To Whom ItMay Concern: TheFederal Aviation Administrationreleased the subject Notice ofProposedRulemaking (NPRM) for comments on September 29, 2015, viaFederal RegisterVolume 80, Number I88, pages 58362-58364. The NPRM proposes to adopt a new Airworthiness Directive (AD) requiring repetitive inspections for cracking ofthe shrouded fuel pipes in the cargo compartment perBoeing SB MD1I-28AI48, dated 8/29/14. This NPRM is proposed due to areport offuel in the aft cargo hold due to a cracked fuel pipe shroudthat also subsequentlyhad an internal fuel pipe leakthus causing the captured fuel (from the internal pipe leak) to escape in to the cargo hold. United Parcel Service Co. (UPS Airlines) has identified many errors in the Service Bulletin that need to be addressed priorto the SB becoming mandatory. SB MD1I-28Al48 section 3.B. Option 1: 2.a. directs a High Frequency Eddy Current Inspection in accordance with Figure I ofthe SB. Figure I highlights only the curved sections (at station I790 "S" bends) ofthe shroud are to be inspected. Itis UPS Airlines understanding that the shrouds are prone to cracking at the straight areas immediately adjacent to the curves where the internal spacers that position the fuel pipe in the center ofthe shroud are located. The spacers are only installed in the straight sections ofthe pipes length, thus the cracks wouldbe expected in the straight section, not in the curved area as Figure 1 depicts. Many aircraft have had the shroudpreviouslyrepaired with the addition ofa doubler perBoeing MDII Standard Repair Manual53-00-0I, Repair 3. The SB does not have provisions to address ifthe shroudhas a repair doubler in place which will prevent the High Frequency Eddy Current Inspection from being performed.Federal Aviation Administration November 10,2015 Page 2 of2

The intent ofAppendix B is to leak checkthe Tail Tank Transfer line shroud system from aircraft station 1501 to 2007 (the length ofshroud/fuel pipe in the aft cargo compartment). While Appendix B does accomplish this, it also checks large amounts ofthe remaining shroud drain system (tail tank components, engine 2 alternate feed line, numerous couplings). Byrendering Appendix B mandatory via AD, it will force upon operators the burden ofleak checking a large amount ofthe shroud drain system not associated withthe intent ofthe AD. UPS Airlinesbelieves the AD/Appendix B should only leak check the portion ofthe TailTankTransfer line shroud from aircraft station 1501 to 2007. UPS Airlines recommends connectingthe air source at coupling#46 (station 2007) to perform the leak check. The intent ofAppendix Cisto leak checkthe #2 Engine Fuel Feed line shroud system from aircraft

. station 1501 to 2007 (the length ofshroud/fuel pipe in the aft cargo compartment). The SB connects an air

source (to leak check the shroud) at a disconnected line/check valve in the tail ofthe aircraft. The SB connects the air source to the wrong side ofthe disconnected line, thus leak checks the shroud aft ofthis point. To leak check the #2 Engine Fuel Feed line shroud system from aircraft station 1501 to 2007 the air source needs to be connected to the side ofthe disconnected shroud line running toward the front ofthe aircraft. Ifthis is to be done it then also creates the same scenario as Appendix B in where a much greater part ofthe fuel line shroud drain system is being checked that is outside the intended scope ofthe AD forcing additional burdenupon the operators. UPS Airlines recommends capping coupling #28 (station 1501) drain port and connect the air source at coupling #31 (station 2007) to perform the leak check. UPS Airlines believes the SB shouldberevised/corrected to: 1. Perform HighFrequencyEddy Current Inspection to the area ofthe shroud adjacent to the installed internal spacers as well as the curved areas. 2. Provide direction ifa previous repair has been accomplished in the HighFrequencyEddy Current Inspection area. 3. Leak check onlythe portion ofthe Tail Tank Transfer line and the #2 Engine Fuel Feed line shroud drain system running thru the left handportion ofthe aft lower cargo compartment from approximately aircraft station 1501 to 2007. UPS Airlines requests that the proposedrule be withdrawn until Boeinghas an opportunityto work with affected MDII operators to develop an accurate SB. Sincerely, UNITED PARCEL SERVICE CO.

# ~~~ EdwardM. Walton Director ofEngineering EW:ML:mrri