Gene Herrera

Refererence NPRM - Docket No. FAA-2010-1164 comment by Gene Herrera Gulfstream Aerospace As OEM of the Astra/SPX/G100 aircraft, Gulfstream is aware of instances where other tube assemblies not called out by P/N in our service information, as having been found to have sponge foam and subsequent corrosion beneath the foam, on 4 other tube assemblies. The relevant service information (SB) currently carries verbiage to the effect of "inspect all fuel tubes, paying particular attention to those specified by P/N". Gulfstream is aware of these other tube assemblies (by P/N) found on various aircraft, that have had instances of sponge foam and corrosion beneath. As OEM, Gulfstream would suggest that the final rule state something to the effect of "the OEM is aware of other tube assemblies that have been found corroded, that are not called out by P/N". Sponge foam has been found on the following tube assemblies with corrosion beneath the tube assemblies, tube P/N 25W653120-643, tube, P/N 25W653120-644, tube P/N 25W653120-571 and tube P/N 25W653120-572. These 4 tube assemblies are part of, or an extension of the tube assemblies called out by P/N in the relevant service information, and terminate in the wing root area or are a continuation of the tubes called out by P/N. Gulfstream would recommend that the final rule make reference to the other 4 P/N tube assemblies mentioned here, and the operator now would know that they would be required to pay attention to these additional tube assemblies. Additionally, the final rule should also state to "inspect ALL tubes in the wheel well areas for this condition". Respectfully Gene Herrera System Specialist Technical Bulletins Gulfstream Aerospace Corporation 7440 Aviation PL Dallas TX 75235 Office 214-902-6184 Cell 214-708-6567 email:gene.herrera@gulfstream.com