szyoud

Dear All,

Greetings,

Our C-130 “G†unit indicator read 4.0 G, I want to know if this indication is over "G" and acceptable or not and if not acceptable what type of inspection is required and which manual should be used to see the required inspection procedures.

Your efforts is highly appreciated

Thank you in advance

Hope you are doing fine,

C-130E heavy white smoke from outlets of the both air-conditioning systems during operation at hot position while all engines are running, we try with #1,#2,#3 and #4 engines the same still heavy white smoke from outlets, when #3 engine is selected the white smoke is more than others, when using GTC bleed air only no smoke for the outlets

Thank for your help

Two things:-

#1: Casey or other moderator, can you split this thread so the origional is separate from

this new thread

#2: Jordan is a relatively high country (I'm assuming Amman) so 70psi at normal ground

idle would be acceptable, especially with summer heat. You need to do a compressor

performance check at 900°C to verify the actual compressor condition.

70psi is not a problem as long as the difference between engines/bleed shut off valves is

not more than 3psi between highest and lowest

Yes my frined I agree with you, but my pilots not acceptable because when you operate one of the air conditioning systems with override position of bleed air regulator & shut off valve the bleed air pressure drops to 63 PSI

Thank you

SZYOUD, your question is not in reference to the original post, correct? We are discussing a different aircraft now? This 70 PSI is with no bleed air load?

If we are on a different aircraft and problem, this should probably been less confusing if it were a different thread.

Assuming all answers above are a "yes" and that you have an aircraft that shows only 70 PSI on the manifold pressure gauge with all four engines running and the bleed air regulator valves in "override," then I wonder if your airfield is a very high altitude one. Are you in Caracus?

If you are not at 13k feet airfield elevation, then you do seem to have a problem.

Inside your horsecollars, you should have a bleed air duct that has a tap-off where you can hook up a good direct pressure gauge. I'd suggest that you put a gauge on one of those ducts and see what the pressure is from the other three engines (one at a time). IF you still get only 70 PSI (since you claim that your bleed air manifold bleed-down time is 10 seconds AND you do not have a newer model Herc that requires more time than that) then you have four bad compressors. (You can also hook a hose up to the pressure test fittings on your compressor diffusers to see what your compressors are actually putting out.)

Seeing that four bad compressors is a bit of a stretch, I'd be looking under the flight deck and behind the Nav's station for a broken bleed air line that goes to your manifold pressure gauge. That very small line - if broken or cracked or if you have a missing cap on a "T" fitting somewhere - will not cause a bleed down check to be bad, but will cause your manifold pressure to read low; that is what I'd hope to find.

I hope this helps. Let us know what you find, please.

thank you my friend for your effort and help

With load read 64PSI one of both air-conditioning operated

My friend my country is Jordan

Direct pressure gauge connected to bleed air manifold aircraft pressure of bleed air still the same

we hook a hose up to the pressure test fittings on compressor diffusers the pressure still reads 70 psi

Flight deck and behind the Nav's station for a broken bleed air line also checked for bleed air leak and broken line nothing found

thank you

bleed air leak check time is within the limits reads 10 seconds

bleed air manifold gage replaced by new one

bleed air valves are regultor & shut off valve

the mulafunction at overide position

Do you have regulating bleed air valves or OPEN closed valves?

What is the bleed air check time?

Maybe as simple as a bad bleed air pressure gauge...

bleed air leak check time is within the limits reads 10 seconds

bleed air manifold gage replaced by new one

to fix it

My aircraft bleed air system manifold pressure gage, reads below 70 psig while all engines are running all engine bleed air regulator & shut off valves replaced by new ones , all pneumatic systems manifold and connections are checked ,both air conditioning checked for air leak, can any one help me about this malfunction