Taimoor

On 12/19/2020 at 8:30 PM, munirabbasi said:

Oh!

Munir Abbasi

Its good to know what others are doing as it might pave a way for our modifications as well!

Is the modification solely avionics based or does it include other systems of aircraft as well, such as air conditioning system?

On 12/13/2020 at 9:21 AM, munirabbasi said:

Use the built-in
diagnostics to troubleshoot the autopilot/flight directory
system. Record all 6 digits in sequence of both left and
right columns of the diagnostics data. Press and hold any
3 active MSP buttons for 2 seconds. The PFD shall
display the REPORT MODE. Use the APP Pitch Wheel
to select the codes.

Munir Abbasi

Defect code was analysed. Problem was with the reversionary relay.

Hello C130 professionals!

In an E Model Hercules, Flight Director Flag (FD flag) came in view on Co Pilot side PFD on ground during normal checks. Against the defect, all associated LRUs were replaced/swapped with serviceable ones. Even the PFD was swapped with pilot side, yet the flag did not disappear. Continuity of wiring was also double checked and was found SAT. No visible issue was observed yet the flag did not disappear. Autopilot engages without any defect and is working fine. Any ideas as to what might cause this or any previous experience, please do share.

Thanks!

8 hours ago, hehe said:

Lots of things are possible.

I mainly said to check the suction boost pump because you said the light came on.  Usually engine pumps will just cause low pressure overall and maybe a low pressure light for that engine driven pump but the suction boost pump light coming on says the supply to both engine pumps was low.

It could have been something as simple as an air bubble making its way through the system when the gear operated.  Keep an eye out for having to service air side of accumulators often.  If the air charge depletes often, it could be depleting into the hydraulic side and creating air pockets in the system.

Were there any hydraulic compnent changes or hydraulic maintenance that happened before this flight?  

Have you bench checked the engine driven pumps?

Yes Air Bubble is one possibility but the precharge pressure of accumulator was not depleted but rather within limits. 

Yes there was one particular component change specific to this system prior to the flight and that was Utility System Accumulator. It was replaced. However as Ive mentioned before, Accumulator was found Serviceable after the flight with Pre Charge pressure within limits, indicating that no Air was depleted into the system.

Both EDPs were bench checked as well and were found serviceable as well. 

On 11/27/2020 at 6:34 PM, munirabbasi said:

Kindly See the VOL,6 -No.3 service news

Munir Abbasi

Home of Hercules Pakistan

Copied Munir Sahab.

On 11/27/2020 at 4:19 AM, hehe said:

Do gear meet timing checks on ground?

If so, Suction boost pump would be my first part to R2

If the accumulator is bad you should find hydraulic fluid in the air side

Yes gears do meet timing checks on extension and retraction tests. Accumulator was bench checked and was found serviceable as well. Suction boost pump was also rechecked and was found serviceable. Can SBP temporarily malfunction?

On approach for landing, a C130 E Model aircraft lowers landing gears only. Flaps are already down. While Lowering the landing gears, utility pressure drops to 1375 PSI and low pressure EDP light of both Engines and low pressure light of Utility Suction Boost Pump illuminated. As soon as the Landing Gears were extended completely, system pressure came back to Normal with all conditions within limit. To what component can this occurrence be attributed? Can it be the failure of Utility System Accumulator, Suction Boost Pump or EDP? And if we were to attribute this to Accumulator, is it possible for an Accumulator to suck hydraulic pressure from pressure line to fulfill its pre charge pressure once it is used? 

Hello there has been an issue regarding the material of intermediate Control Rod on Allison T56 A15 engine on C130 E models. Can someone guide me about the material from which these rods are made (is it non ferrous or stainless steel?) and what NDI Inspection is to be carried out on these rods (FPI or MPI)?