pgindy

Hey all, We recently had an issue with a plane C130 J model when it comes to bleed downs as well as fumes and smell of burnt rubber when up speeding 2 of the engines. Crew report smell of burnt rubber when they up speed. We did a bleed down and it's not very close to passing. The bleed down with all 4 engines open is about 15 seconds, all 4 engines closed 14 seconds. If we isolate further and close the L and R Wing iso valves it drops to about 12 seconds. This led me to believe the problem is somewhere between the APU and bleed air ducting in the cargo. I've tried to feel for leaks along all accessible ducting and have yet to find any leaks. Any inputs/suggestions on what could cause such a bad bleed down as well as a smell of burnt rubber when upspeeding the engines? I have hand felt the associated ducting/iso/divider vales, external air connect check valve. Next on the list was the apu bleed air check valve. Any input would be greatly appreciated!

Hello everyone, For the past month or two we've been having an ongoing issue with pressurization on our J model. The problem typically gets recognized when flying at higher altitudes, 19-20k ft, thought recently they've stated they had erratic pressurization at all altitudes. Initially the problem was erratic pressurization throughout flight, resulting in ears popping and discomfort, when at higher altitudes they received a CAB Alt high advisory because cab alt was indicating above 10k ft. We change a part, it flys 1-2 times and the problem comes back. We've changed the outflow vlv, cabin pressure controller, vacuum reg, and servo valve, some things have been changed twice to no avail. Anyone dealt with something similar/have any potential suggestions? Thanks!