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Everything posted by Lkuest

  1. I'm quite a bit rusty and I'm sure everyone has their own callouts, but I've never called "valve" during my engine starts, it was always "button out". My best guess is the "valve" callout would only apply to aircraft equipped with the start valve light. If the valve was still open (light on) in LSGI, the starter is likely still engaged by a stuck valve, which would make it an important thing to call out.
  2. If you are at power, actuate the switches, and the RPM does not increase at all and fuel flow does not decrease at all, the problem is in the synchrophasing system. This includes the switches, wiring, and valve housing electrical components. Without the electrical components being good, neither the pitchlock regulator nor the fuel control can cause the issue because they're not given the opportunity to do anything. This also assumes the low pitch stop is adjusted correctly.
  3. If RPM is staying at 100%, and the pitchlock check is the only check that is failing, the only thing that remains is a wiring issue or the switch is broken. I highly recommend you break out the wiring diagram and start checking for open circuits.
  4. NATOPS essentially already answered this question above. The analog indicator is allowed to be 2% low and still be considered safe for flight. There is a different RPM limitation for a digital indicator. If the RPM actually dropped below 94%, the bigger problem would be high TIT, low torque, and likely flameout. If you are reading 92.5 but the temperature and torque nearly match the other engines, the RPM is above the Speed Sensitive Valve transition of 94%.
  5. I seem to remember going over 100 deg C just resulted in pulling the mag plugs, and going over 150 is an oil change. Pulling the mag plugs is to check for damage, then put them back in. My guess is 100 deg C is the limit because that's the point when damage becomes much more likely. If I had to guess why this causes an engine shutdown event, I'd say only a malfunction could allow the oil temp to go above 100 while flying due to the robust amount of cooling air available. If the engine is shut down for oil temps, it is a good idea to get the engine restarted for landing for maximum controllability and go-around margin. As for a reference, my guess is whatever tech data the owner provides. For the US military, that would be the 1C-130H-2-70FI-00-1-2.
  6. Gimme the BPO work cards and 1 hour, and I'll throw down three "red-x's" and 20 "/'s"
  7. Only thing I would add to pjvr99's response is consider resealing the low pitch stop too. I'd almost bet money the squeal check would fail.
  8. Here's the source website for service news bulletins. https://www.lockheedmartin.com/en-us/who-we-are/business-areas/aeronautics/sustainment/customer-support-center/service-news-magazine-archive.html
  9. If the orifice cups are clogged, you will never be able to accurately check servicing, as the pressurized sump may always show good, but at the expense of the atmospheric sump. The atmospheric sump is allegedly the most accurate location, so if it's inaccurate, it will always lie to you. You should check your tech data for how to clean the orifice cups. The only other option is to replace the pitchlock regulator, preferably with one that was recently overhauled to guarantee the cups are clean. One indication the orifice cups are clogged is that, when you check the pressurized sump after 2 minutes, the fluid fills up and overflows. This is due to the pitchlock regulator keeping the fluid pressurized in the system instead of draining the fluid into the barrel like it's supposed to. Be careful of those who tell you only the pressurized sump is required for an accurate fluid check. This comes from the idea that the pressurized sump dipstick actually gives you a quantity, and the atmospheric sump is only a go/no-go. The only thing the pressurized sump dipstick tells you is how much fluid is in the pressurized sump, who's job is to force-feed the pumps sending the fluid out to the valvehousing. The atmospheric sump dipstick tells you how much is in the barrel AND atmospheric sump. If there's nothing on the atmospheric dipstick, you have no idea how much is in the barrel, and that can be dangerous.
  10. It is likely your orifice cups are clogged, preventing proper filling of the barrel assembly, and therefore your atmospheric sump
  11. This sounds strange. I'd almost suspect you had a bleed valve stuck open on one of the other engines, or there may be a wiring problem within the anti-ice system that is affecting indication. Does the engine pitch sound like it's roaring to life? Does the aircraft actually yaw a bit in the direction of the increased torque indication? I would also be interested to hear how all 4 engines behave together when all bleeds are open and the wing & empennage are actuated. Please, for clarity, when you say TIT remains the same, can you please specify whether the TIT momentarily moved up/down and corrected, or did the TIT simply not move? Can you verify the wing and empennage valves have proper function. Please clarify how much each indicator is moving when wing and empennage anti-icing is actuated Really, the only reason for torque to significantly increase with a steady TIT is the engine suddenly becomes more efficient by retaining more air within the engine, or the indication is lying.
  12. does this happen with only that single engine bleed air valve open, or are all 4 engine bleed air valves open? Do you have dummy bleed air valves, or bleed air regulator valves?
  13. I recommend checking the NTS gaps, Low Pitch Stop blade angles, and Torque Retaining Lugs for all 4 propellers, as well as note the results of the in-flight NTS checks.
  14. I agree with NATOPS, once the engine shuts down, any fluid pressure from the still-spinning pumps will go directly to the increase-pitch side of the dome via the feather valve and feather actuating valve until the pumps can no longer supply 100 PSI. Then the blades stop changing pitch. Since the internal seals for each propeller are worn differently, it's difficult to nail down a specific degree when you transition through that pressure. Also, as you are flying, airflow is still trying to spin the propeller beyond what it would be during a ground run. I doubt you will get all the way to feather, but you should get far enough to make sure propeller drag isn't dangerous. Think of the propeller as an air brake which either absorbs or transmits airflow energy. If the airflow is inadequate to continue spinning the propeller, then the propeller resistance to airflow is naturally going to be low. I am unfamiliar with the flight manuals, so purely from a maintenance standpoint I also want to emphasize that you will still have 28vdc attempting to actuate the propeller feather solenoid, so once the blades stop changing pitch, the propeller feathering circuit may still be energized, both overheating the circuit as well as sucking DC voltage if that bus is powered. Check your flight manual to see if you need to manually pull the feather override button up if the propeller blades stop changing pitch, but are not all the way in feather.
  15. I recommend your military request technical data upgrades. I've never even seen a 1C-130B-2-4, so I have no idea what information I could add to help you troubleshoot your problem. With updated technical data, you might be able to do this on your own. As with most fluctuations, it is much easier to recommend a maintenance action if I was able to see all the engine instruments. Just about anything can cause a torque flux, and "all wiring" is a pretty broad statement.
  16. I would be interested to know what kind of troubleshooting manuals you have available to you.
  17. I agree with pjvr. What you are describing is a throttle misalignment below crossover, for which there is no limit. If everything else is within limits, there isn't a problem. If you are still really concerned about this, you could check for air leaks, but you should also have lower torque and slower starts. You could also adjust the TD Valve and/or Fuel Control, but ONLY if the rich/lean check shows rich AND you have warm start temperatures and well within normal start times. Otherwise, it sounds like the TD system is doing its job well, and stops controlling when it's supposed to stop controlling.
  18. If TIT, Fuel Flow, and Torque are all low together with no change in RPM, whatever is causing the problem is definitely fuel related. Have you run an electrical check on all wiring? Some of the electricity goes through the LH engine wiring harness, and there is a J3 lead that can cause problems. You might also hook up the TD Amp test set and shake the wiring around to try to duplicate. You should also pull the lid off the junction box next to the TD Amp and see if anything looks out of place.
  19. Was RPM doing anything, and if so, which direction in relation to TIT? Also, were torque and TIT low together, or opposite each other?
  20. As a maintainer, I've seen this a few times, both with engine running and during static pitch changes. Also, with the throttle in any position, as well as reversing with the condition lever in feather. I've never had an aircraft from my unit reverse in flight during the 200,000+ flight hours worth of malfunctions I've either worked or got turnover for, but I do believe this eventuality is covered in simulator training.
  21. This really needs more detail. Try to describe the malfunction in detail so we can get a mental picture of what's going on. Torque dropped for only 2 seconds. Which 2 seconds? At the beginning of the 5 seconds that RPM was low? At the end of it? If torque and RPM dropped together, it would indicate air as a likely cause. If Torque stayed high when RPM dropped, then that would indicate a propeller malfunction, and TIT happened to shoot up due to the SCV opening at 94%. If TIT shot up only after RPM dropped to 94%, that would further indicate the propeller as the cause. If TIT shot up before RPM dropped, then that would point to an air malfunction. How did the engine recover? Did you turn off bleed air, adjust the TD switch, or did it come back on it's own? Is there a history? How many hours are on the compressor? You're also missing fuel flow, which might help indicate a fuel or TD system malfunction. You might also include much TIT and Torque moved, as well as the pressure altitude and outside air temperature. A very slight TIT increase might indicate it was fuel related because once the SCV opens, the TIT should shoot up a lot. A large TIT increase should eliminate fuel system as the cause. A SCV malfunction is usually only good for about 5000 in-lbs of torque at power and around sea level, but I'm sure the power loss could get much more severe at high altitude or hot conditions and engine wear level. There's just too many variables for us to be truly helpful with the little information that was provided.
  22. I'm assuming a BARV is a Bleed Air Regulator Valve, and when you say "accompanied of TIT", you mean TIT dropped with torque, and not increased. The TD Amp's job is not to maintain power, but to maintain temperature based on the throttle setting. If the TIT is low while the TD Amp is in AUTO, then there is an error with a signal being supplied to the TD Amp, or there is an error with the Amp itself, a setting or malfunction, When you lose air, you lose power for two reasons. Jet engines love more air, both to increase power through expansion, and also to keep the combustion chamber cool. If you lose air, you lose power immediately since there is less air to expand, but also the loss of cooling air causes an increase in TIT, and results in the TD Amp to pull fuel back. This all produces a loss of torque and fuel flow while maintaining TIT. I cannot emphasize this enough, before doing anything, ensure your indications are accurate! TIT to within 6 degrees of actual as measured with a test set and all thermocouples verified good and connected properly. Torque indicator recalibrated and set to within 50 in-lbs of actual. Swap the Fuel Flow gauge with a known good one for good measure, then reverify the problem. Why the engine goes to normal when the Regulator Valve gets turned off is interesting. If the TIT was to remain normal, I would say the Regulator Valve was mis-tuned and the TD Amp was doing its job. Since the TIT is also low, we know the TD Amp is not doing its job (above crossover only). Even if the Regulator was malfunctioning, the TD Amp is definitely having an issue. The fact that the valve affects the TD System operation means they may be connected electrically in some way, like the power/signal wires may be chafing together. If the fuel control was perfectly tuned and we suspected the TD Amp was just inop, we would see high TIT with bleed air open, not low TIT. To check if it is an electrical problem, check power going to the TD Amp using a TD Amp Test Set, then cycle the bleed air valve and see if the power at the Amp changes. There are two types of power going to the Amp, so check them both. If I misunderstood you, and the TIT is high during the malfunction, and not low, then you have a TD Amp malfunction AND a bleed air regulating valve balance issue causing you to lose 2500 in-lbs.
  23. Is the engine operating within limits? If so, disregard the differences as there is no limit for symmetrical operation in HSGI. Otherwise, you might consider checking rigging with the valve housing, or swap it with a known good valve housing, as long as the Fuel Control has already been eliminated. I know the prop causing fuel flow problems sounds weird, but I've had it cause stranger problems in HSGI.
  24. I'm sure if the boss wants it to get done, it will get done one way or another. Seriously though, it depends. If you're looking for justification for an argument, the 61-series job guides are meant to be used by the specialists, so if that's the tech data being used, the engine folks are doing it. If the 12-series job guides are being used, then it's APG doing the check. By concept, APG is in charge of all routine maintenance. In practice though, if an engine troop doesn't have work, he's doing it. If engine troops are busy, it could go either way. Not sure if it really matters who does it, as long as they do it right. I've seen a few APG folks grab the wrong color can, so do what your comfort allows you to do.
  25. I agree, all you can really do is a check first stage rotor blades, balance, and a good signature check. If all those are good, you might just be having bad luck. We've gotten quite a few that crack again and again, mostly due to poor weld repairs on the replacement supports. If the signature run is good, you might try installing a known brand-new case and see if it still cracks. Of note, the rear bearing support case wasn't originally designed to mount a tailpipe, so the extra length acts as a cantilever to amplify vibrations through the weak points. The support case is Allison, and the tailpipe is Lockheed. That's why vibration is the top cause, but also explains why you might have nothing wrong with the rotating assembly and still get cracks.
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