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torque indicator cal problems


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WC-130h PRT AF 

Hi everyone pls help

As to start calibrating the torque indicator it indicates aprox. -800lbs. After reseting to the 29850lbs with cal A with -4000lbs and cal B with 25850lbs still with neg torque all checks done and recheck wiring , gapping and so on. To put positive torque cal A must have -2340lbs and cal B 27200, by the way it torquemeter has 27540lbs from back shop. Are these values normal for service?

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no minimum value stamped on tm. T.O. says unload engine by turning off bleed air, generator and hydraulic pump. Then move

throttle slightly forwards or backwards to obtain LOWEST torque indication. Adjust CAL-A/CAL-B -4000/25850. If the difference

between INDICATED torque and CALCULATED torque is more than 750"lb reject torquemeter and return it to overhaul.

 

 

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Hi

first I would like to thank you for answering my question!

This engine in question came from overhaul as well the torquemeter, the value from backshop is 29540, and they said to put on cal A -2340 and on cal B- 27200. As I started to calibrate the indicator with the standard value (29850), like you mentioned before, when reading the indicator it showed -800lbs torque, while trying to get positive torque reading the only values I could put on the indicator was -2600 and 27200. the indicator wouldn t go under the -2600. Changed three indicators and all showed the same. the reading was 500 lbs and could not go any higher(needed to be 700lbs).

The point here is, I think the negative value for the cal A is out of standard as well the torquemeter, did the NTS check on air and did not get negative torque readings or lights on. Being talking with fleet management, and they say, all is normal according to OGMA, SA which is the back shop company.

So what do you think about these values?

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OK I think you may have two different issues.

I would  start with the mechanical side and verify all blade angles (low pitch stop, ground idle, reverse, feather, flight idle) and NTS gaps (anti rotation (drive) bracket, gearbox to NTS bracket and NTS bracket to valve housing) change or disassemble and lubricate the NTS bracket. Make sure to rotate the valve housing assembly to check the drive bracket gap.

 

Question: the aircraft flew with out accurate torque indications and NTS was checked? I caution because there is a maximum negative tq limitation during the check which I'm sure you are aware of but just wanted to make sure... 

 

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On 11/17/2017 at 12:56 PM, ermitao said:

This engine in question came from overhaul as well the torquemeter, the value from backshop is 29540, and they said to put on cal A -2340 and on cal B- 27200. ...........

So what do you think about these values?

If torquemeter stamped number is 29540 then corrected cal-A of -4000 would give corrected cal-B of 25540. Assuming ISA conditions

and 72% rpm, you would be looking at 709"lb torque calculated. Setup indicator as per 1C-130H-2-77JG-00-1   77-10-04. A difference

of more the 50"lb will require corresponding adjustment of the guage. A difference of 750"lb requires tm remove from service. Try my

min torq calculator if I am not clear .....

Perf_PPC_v2.1.xlsx

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All blade angles were checked, everything is ok. On the first flight to check nts the engine it did not reached negative torque. There is a situation that while I was trying to calibrate the indicator to the values given (CAL A -2430 and CALB 27120), I could not put these values on the indicator because it reached the limit, I try with three indicators and none of them reached the value of -2430 and stopped on the -2600. The fleet manager brought me an indicator from the engine test bench of the same company mentioned above, to my surprise it worked. In my opinion this indicator was "worked " thats why it got to these values. COC´s were checked of the torquemeter and of the new indicator, they all say its within standard values. Another flight engineer did another flight and this one gave thumbs up to the plane, I `m not sure where this is going to but i dont have agood feeling about this. I was hoping that anyone would know for sure about these values of the torquemeter and of the indicator. Thanks for all the replies

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Hi , I know that the values are wrong, entering the standard values I cannot have positive torque it gives -800lbs  on the reading , I wanted to proof that this values are wrong  or that something is wrong with the torquemeter shaft. Fleet manager believes truly on what OGMA SA says and they say that this values are normal!

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On 23/11/2017 at 2:02 PM, oziejo said:

Hi , I know that the values are wrong, entering the standard values I cannot have positive torque it gives -800lbs  on the reading , I wanted to proof that this values are wrong  or that something is wrong with the torquemeter shaft. Fleet manager believes truly on what OGMA SA says and they say that this values are normal!

If he believes values are normal while you think they're wrong, he should sign the damn paper then (if any).

It's strange to have something fresh out of overhaul to have wrong values, however mistakes happen so if you're sure, try to see if anyone who's able to take such measures agrees with you, with someone else agreeing with you, maybe your fleet manager will try to start thinking about it.

Any updates about this by now ?

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I've been down this road before - the numbers his fleet manager is insisting they use are not correct. My test cell has

digital and analogue torque indication. The digital easily spans numbers like that, the analogue guages cannot. I was

proven right when my boss had one of the tm i failed sent to RollsRoyce for evauation. Report came back with 7 

defects including excessive twist (overtorque) of the torque shaft. The tm unit had been overhauled by another

facility

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  • 4 weeks later...
  • 1 month later...

Hi victorp1

yes, while we were trying to calibrate the indicators, we put it on engine #2 and did calibrate on the standard values only on this engine did not calibrate. Well it did calibrate but with the values non standard (CAL -2140; CAL B - 27350)

 

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