unknown52 Posted August 31, 2011 Share Posted August 31, 2011 we had a bad abex pump on #1 eng. swapped out with parker and ran engines. all ops cks were good. original write up was landing gear down and pump light came on. so we recreated it and nothing. we ended doing it again with #2 pump off and went flaps down and while moving flight controls (not what i was supposed to do but new to hydraulics and did it thinking everything would ck good) and pressure dropped to 700 and the pump light came on. switched #1 off and put #2 on (parker pump) and the pressure dropped to 2000 with no light. switched pumps from #1 to #2 and #2 to #1, issue followed pump. been told this is normal but just doesnt make much sense to me, because of the issue of losing the engine with abex on it. scenarios: one engine flaps and flight controls moving parker 700 psi abex 2000 psi one engine just flaps parker 1200 psi abex 2500 psi one engine just flight controls parker 3000 psi +/- 200 psi abex 3000 psi +/- 200 psi both engines all tests 3000 psi Quote Link to comment Share on other sites More sharing options...
unknown52 Posted August 31, 2011 Author Share Posted August 31, 2011 also swapped the parker out again thinking bad pump from supply, but same numbers. Quote Link to comment Share on other sites More sharing options...
NATOPS1 Posted August 31, 2011 Share Posted August 31, 2011 Our books have the notation that a low pressure warning light may illuminate with only a single pump under high load conditions IE Gear movement. Quote Link to comment Share on other sites More sharing options...
unknown52 Posted August 31, 2011 Author Share Posted August 31, 2011 well the thing we were wondering was the gap in pressures. and the only thing we could find was under the -1 and it says to expect a drop in pressure but doesnt reference a light coming on. and the dash one says if the light illuminates to shut the pump off, which on approach with one left engine and if the light came on the other left engine that would leave u with no gear. Quote Link to comment Share on other sites More sharing options...
NATOPS1 Posted August 31, 2011 Share Posted August 31, 2011 I agree that it would seem as if you would "turn off" the pump if the light illuminated but if you know something may happen and/but you can directly associate its occurance to an event ("gear down") you would not... Quote Link to comment Share on other sites More sharing options...
unknown52 Posted August 31, 2011 Author Share Posted August 31, 2011 WELL AGREE WITH THAT BUT IT DOES SEEM DIFFERENT BETWEEN PUMPS AND HAVENT BEEN GIVEN ENOUGH INFO OR REASONING TO LET IT GO WITHOUT ANY INVESTIGATION. WE FILLED OUR 107 FOR LOCKHEED (ONLY GOD KNOWS WHEN THEYLL GET BACK TO US), BUT FIGURED MAYBE SOMEONE HERE HAS SEEN THIS BEFORE AND DID BETTER RESEARCH. AND I HAVE TALKED TO PLENTY OF PILOTS AND FE'S THAT SAY THEY SEE A DRASTIC DROP WITH ONE ENGINE NO LIGHT AND ONLY ONE FE HAS SAID THEY HAVE SEEN THE LIGHT WITH ONE ENGINE. (UNLESS THERE WAS AN ISSUE). Quote Link to comment Share on other sites More sharing options...
Dan Wilson Posted September 20, 2011 Share Posted September 20, 2011 In normal ops you should Not see the Press Low Light by dropping gear or actuating flight controls. Natops, if you book read like mine did, the reference to low pressure light coming on with gear actuation is actually in the EP section and its under the pump out procedures where it says you might see this when operating with a single utility pump. Sorry I cant quote anything, its been about a decade since I had the -1 in my hands. Quote Link to comment Share on other sites More sharing options...
Ben Legere Posted October 5, 2011 Share Posted October 5, 2011 If your engine pump puts out 8.6gpm at 2525psi and you'r elevator bypasses at 3gpm when on the stops. That leaves you with 5.6gpm to play with. Guess what? You'r flaps have a 9.8gpm flow rate limit. That leaves you with -4.2gpm. Not every pump puts out 8.6gpm, the old stratopower pumps were only rated for 5.6gpm. Check SBSS when you get a chance or fedlog to get the characteristics for the different pumps, you will be surprised at how far off from the real limits they make pumps. I'm wanting to say that the Abex pump is rated for 9.2gpm but I am not at work to verify this. Look at the id tag on the pump if you want a quick reference. Anyhow, a drop to 700psi with one engine on speed while running just the flaps through is nothing to worry about and is quite common. Not everything is in a T.O. and sometimes it takes a little common sense and system know how to explain things. It's too bad that 99% of the people out there just go off of what a book says and never really looks into how something actually works and why it does what it does. I have yet to see a T.O. that tells you how to turn a screwdriver, yet people twist them instead of pushing on them. Using a little common sense goes a long way, although it may be hard to convince an engineer that the utility reservoir drops about 4" when the gear is retracted and it is perfectly normal. All that fluid fills up the nose landing gear actuator when the gear is retracted. There is no book that says that the fluid can drop. This is one of those cases where you have to be able to understand how stuff works. I have put in countless TO changes just to have them denied then stolen and submitted by dickbags that want credit for everything. Some quick and easy things that every hydro guy should know about the 130 as far as pressures - with both engines downsped pressure can drop as low as 2,550psi - If a suction boost pump fails you can continue to fly, hydraulic pressure can reach as low as 2500psi with a failed suction boost pump - A clogged vent filter can cause all kinds of weird pressure problems Quote Link to comment Share on other sites More sharing options...
bischoffm Posted October 5, 2011 Share Posted October 5, 2011 If your engine pump puts out 8.6gpm at 2525psi and you'r elevator bypasses at 3gpm when on the stops. That leaves you with 5.6gpm to play with. Guess what? You'r flaps have a 9.8gpm flow rate limit. That leaves you with -4.2gpm. Not every pump puts out 8.6gpm, the old stratopower pumps were only rated for 5.6gpm. Check SBSS when you get a chance or fedlog to get the characteristics for the different pumps, you will be surprised at how far off from the real limits they make pumps. I'm wanting to say that the Abex pump is rated for 9.2gpm but I am not at work to verify this. Look at the id tag on the pump if you want a quick reference. Anyhow, a drop to 700psi with one engine on speed while running just the flaps through is nothing to worry about and is quite common. Not everything is in a T.O. and sometimes it takes a little common sense and system know how to explain things. It's too bad that 99% of the people out there just go off of what a book says and never really looks into how something actually works and why it does what it does. I have yet to see a T.O. that tells you how to turn a screwdriver, yet people twist them instead of pushing on them. Using a little common sense goes a long way, although it may be hard to convince an engineer that the utility reservoir drops about 4" when the gear is retracted and it is perfectly normal. All that fluid fills up the nose landing gear actuator when the gear is retracted. There is no book that says that the fluid can drop. This is one of those cases where you have to be able to understand how stuff works. I have put in countless TO changes just to have them denied then stolen and submitted by dickbags that want credit for everything. Some quick and easy things that every hydro guy should know about the 130 as far as pressures - with both engines downsped pressure can drop as low as 2,550psi - If a suction boost pump fails you can continue to fly, hydraulic pressure can reach as low as 2500psi with a failed suction boost pump - A clogged vent filter can cause all kinds of weird pressure problems Not to be a smart ass, but the T.O. for the use of hand tools to to include screw drivers is AIR FORCE TO 32-1-101 section 22 You have got to remember the Air Force has practically everything! Quote Link to comment Share on other sites More sharing options...
Ben Legere Posted October 6, 2011 Share Posted October 6, 2011 Not to be a smart ass, but the T.O. for the use of hand tools to to include screw drivers is AIR FORCE TO 32-1-101 section 22 You have got to remember the Air Force has practically everything! It tells you how to make sure that it fits correctly and not to pry with it but I have not seen anything stating that you have to turn it to make it work other than the little note in there that says that you can use a wrench to turn it if needed. Nothing states that you have to twist the handle with your hands though. Quote Link to comment Share on other sites More sharing options...
bischoffm Posted October 6, 2011 Share Posted October 6, 2011 (edited) It tells you how to make sure that it fits correctly and not to pry with it but I have not seen anything stating that you have to turn it to make it work other than the little note in there that says that you can use a wrench to turn it if needed. Nothing states that you have to twist the handle with your hands though. Read paragraph 22.4.2.3 (Using a screwdriver) turn clockwise to screw in and counterclockwise to unscrew (that's rightie, tightie leftie loosy) Sorry about hijacking this post!!!!:cool: Edited October 6, 2011 by bischoffm Quote Link to comment Share on other sites More sharing options...
Ben Legere Posted October 7, 2011 Share Posted October 7, 2011 Dang... I read it... I could have sworn that it didn't say anything about turning a screwdriver, but I stand corrected... Quote Link to comment Share on other sites More sharing options...
bischoffm Posted October 7, 2011 Share Posted October 7, 2011 Dang... I read it... I could have sworn that it didn't say anything about turning a screwdriver, but I stand corrected... no worries!! I just wanted to correct that point the rest of you pump statement made sense, I've seen no one state that it was wrong, Finding TO's to help the troop is my job, that is why I had the answer to that, here to help. Quote Link to comment Share on other sites More sharing options...
SEFEGeorge Posted October 7, 2011 Share Posted October 7, 2011 Sometime in the early months of my Fe training my instructor said that the hydraulic pumps were called "California" pumps. Why I asked. Nine pistons, 3 sucking, 3 blowing, and 3 fking off. Quote Link to comment Share on other sites More sharing options...
bischoffm Posted October 8, 2011 Share Posted October 8, 2011 Sometime in the early months of my Fe training my instructor said that the hydraulic pumps were called "California" pumps. Why I asked. Nine pistons, 3 sucking, 3 blowing, and 3 fking off. :D Quote Link to comment Share on other sites More sharing options...
tusker Posted October 8, 2011 Share Posted October 8, 2011 OK Ben!!!.....now is the time!!....Where are you from and what do you do for leaving!!!....You look like a guy from New Brunswick...Canada.........Do you work on those magnificience machine....C-130 Hercules from Lockleed!!....or else!!!.. Loosen up!!! Do not be afraid!!!Be yourself!!!!!........................The Bad John!! Quote Link to comment Share on other sites More sharing options...
Ben Legere Posted October 9, 2011 Share Posted October 9, 2011 My name is Ben, I am not from Canada and I still can't figure out who thought that it would be a good idea to make the boost pack manifolds out of cast 2014 aluminum. Sometimes I wonder why a MLG strut only takes 30,000ft lbs of torque to shear off or why J models use less than adequate engine nacelles. I work on planes and am extremely bored with my job which puts running and looks ahead of knowledge based merit. Quote Link to comment Share on other sites More sharing options...
HercMaint Posted October 10, 2011 Share Posted October 10, 2011 why J models use less than adequate engine nacelles. They are actually old T56 nacelles that Lockheed were too cheap to re-design and Rolls Royce were the only ones who were willing to squeeze a new engine into the old nacelle. It still does the job though :) Quote Link to comment Share on other sites More sharing options...
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