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 of Proposed Rule Making (NPRM) 20I4-NM-2I9-AD; Docket No. FAA-20I5-

3637 

To Whom It May Concern: 

The Federal Aviation Administration released the subject Notice ofProposed Rulemaking (NPRM) for 

comments on September 29, 2015, via Federal Register Volume 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 per Boeing SB MD1I-28AI48, dated 

8/29/14. This NPRM is proposed due to a report of fuel in the aft cargo hold due to a cracked fuel pipe 

shroud that also subsequently had an internal fuel pipe leak thus 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 prior to 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 of the SB. Figure I highlights only the curved sections (at station I790 "S" 

bends) of the shroud are to be inspected. It is 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 of the shroud are located. The spacers are only installed in the straight sections 

of the pipes length, thus the cracks would be expected in the straight section, not in the curved area as 

Figure 1 depicts. 

Many aircraft have had the shroud previously repaired with the addition of a doubler per Boeing MDII 

Standard Repair Manual53-00-0I, Repair 3. The SB does not have provisions to address if the shroud has 

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 of Appendix B is to leak check the Tail Tank Transfer line shroud system from aircraft station 

1501 to 2007 (the length of shroud/fuel pipe in the aft cargo compartment). While Appendix B does 

accomplish this, it also checks large amounts of the remaining shroud drain system (tail tank components, 

engine 2 alternate feed line, numerous couplings). By rendering Appendix B mandatory via AD, it will 

force upon operators the burden of leak checking a large amount of the shroud drain system not 

associated with the intent of the AD. UPS Airlines believes the AD/Appendix B should only leak check 

the portion of the Tail Tank Transfer line shroud from aircraft station 1501 to 2007. UPS Airlines 

recommends connecting the air source at coupling #46 (station 2007) to perform the leak check. 

The intent of Appendix Cis to leak check the #2 Engine Fuel Feed line shroud system from aircraft 

. station 1501 to 2007 (the length of shroud/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 of the aircraft. The SB 

connects the air source to the wrong side of the disconnected line, thus leak checks the shroud aft of this 

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 of the disconnected shroud line running toward the front of the 

aircraft. If this is to be done it then also creates the same scenario as Appendix B in where a much greater 

part of the fuel line shroud drain system is being checked that is outside the intended scope of the AD 

forcing additional burden upon 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 should be revised/corrected to: 

1. Perform High Frequency Eddy Current Inspection to the area of the shroud adjacent to the 

installed internal spacers as well as the curved areas. 

2. Provide direction if a previous repair has been accomplished in the High Frequency Eddy Current 

Inspection area. 

3. Leak check only the portion of the Tail Tank Transfer line and the #2 Engine Fuel Feed line 

shroud drain system running thru the left hand portion of the aft lower cargo compartment from 

approximately aircraft station 1501 to 2007. 

UPS Airlines requests that the proposed rule be withdrawn until Boeing has an opportunity to work with 

affected MDII operators to develop an accurate SB. 

Sincerely, 

UNITED PARCEL SERVICE CO. 

~~~ Edward M. Walton 

Director of Engineering 

EW:ML:mrri