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pjvr99

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Posts posted by pjvr99

  1. thank you Paolo, have you checked the oil tank for contamination

    or blockage? also check the oil supply hose (flexible) from tank for

    collapsing. If it only cuts out under load, you may have a fuel 

    starvation problem - take a look at the fuel filter on the fuel cluster

    and also the filter up in the wheel well

     

    just out of curiousity, is the APU part no 381116-1-() or 381116-3?

  2. As NATOPS1 asks, can the APU be restarted immediately or do you need to wait for a

    time? Likely causes can be oil pressure, load control/acceleration thermostat, faulty

    overspeed solenoid, or some electrical interruption. If you have an APU test stand

    available, I would recommend running the APU there and try to duplicate the 

    problem.

     

  3. assuming you have already swapped guages, so i would then shoot TIT from

    the firewall using TD tester, and bumping the TIT wires all the way to the

    cockpit. Next step would be to check power wires to the guage, and also 

    whether it is grounded properly. 

     

  4. 10 hours ago, Shola said:

    Model of the APU is GTCP80-180L. Part Number of the APU is 381116-1-7. Thanks a lot. 

    Ok was just curious. Gonna go out on a limb here because we had something similar 

    last year. Try replacing flexible oil hoses to and from the oil tank, and make sure the

    rigid lines and the tank are clean and free of contaminants

  5. Hey guys

     

    Wondering if anyone can help me with info on the N prefix on the blade

    serial numbers. We have just gotten a TCTO covering a number of

    blades. Some of the serials are N8xxxxx others are just 8xxxxx. What

    does the N refer to .....

     

    Tnx in advance

     

    PJ

  6. Cutback is a misleading term, as the TIT before correction may be lower than corrected TIT. For example, TIT before

    light out may be 790°C and 835°C after light out. There was an increase rather than a cutback. AGAIN, there is NO

    limit for TIT before light out, only 800 to 840 after light out.

    • Like 1
  7. For several weeks flight and ground crews have been pecking away at a problem where engine torque, fuel flow 

    and TIT increase when engine anti-icing is turned on. We're not talking 100"lbs of torque here, its over 4000"lb

    and/or 300 to 500 pph of fuel. Every conceivable component from FCU, speed valve, anti-icing side valves, and

    the whole TD system has been replaced at least once with no change.

     

    Last week the engine was finally removed and sent to test cell. Engine was started, runs great, makes good power,

    but when anti-icing is turned on there is a massive surge of torq and fuel which the TD barely contains. I had the 

    to see what happens in NULL - instant soil-the-underwear moment as torq jumps from 12500"lb to almost 18000"lb,

    fuel goes 1600pph to 2000pph, and TIT from 900°C to 1040° ......

     

    I have a small flapper installed over the inlet duct anti-icing vent so we can see when the anti-icing valve opens. This

    device was working as intended, meaning a/icing on flapper flaps, but ...... massive torq, TIT and FF increases.

     

    We eventually shut down the engine without any real idea of how to proceed with troubleshooting. Then I started

    thinking: what if, somehow, a/icing air is getting into the FCU CIT or CIP lines .... Some examination of diagrams

    led me to the CIP inlet in the compressor inlet housing. A/icing air is pumped into the same strut  as the CIP

    fitting. If the fitting is corrode, cracked or loose, you'd be dumping 100psi air onto the CIP bellows.

     

    Long story short, a really skinny guy was sent up the 'S'-duct and CIP fitting was replaced. VOILA! A/icing no

    longer causes massive increases in torq, ff, and TIT

    • Like 1
  8. 2 things will happen here:

    1- you will lose the commercial (civilian) certification for the D22

    2- you will have no fuel flow indication.

     

    The T56 engine uses a 28v DC power supply for the ff transmitter and indicators, while 

    the D22 uses a 115v 400hz power supply. The wiring and connectors are completely

    different.

     

    In my opinion this would be a completely wasted excercise, not to mention the expense

    of recertifying the D22 again

    • Like 1
  9. Probably want to keep APU shut down when taxing on dirt or unprepared strips. Having

    said that, the intake screen holes are big enough to let in small gravel and stones which

    can and will damage the compressor when it is started again ....

  10. OK. big scavenge problem. How is oil temperature?

     

    Pull off lower E-duct from 14th stage. check the #2 & #3 bearing lines visible for oil staining. After

    that check #2 & #3 bearing lines to the external scavenge pump that they are not blocked.

     

    Heve you changed main oil pump yet?

  11. What is the difference in indicated oil quantity with engine running at 100% rpm and indicated oil qty

    immediately when engine is shut down (no rotation)?

     

    During ascent/descent are the oil pressures steady, or is there a fluctuation? Is there any fluctuation

    on the ground?

     

    Did the engine go across test cell before going back to aircraft?

     

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