engine parameters log difference
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engine parameters log difference
Hi
PW-207 all looks normal ? wondering why there is such a difference in CT CNC , IM CNT ? since new both engines always start and run normal
PW-207 all looks normal ? wondering why there is such a difference in CT CNC , IM CNT ? since new both engines always start and run normal
What do CT and PT stand for? I assume compressor turbine and power turbine. If so could. it have something to do with OEI training?
Every aircraft I flew with an OEI training switch had a big DO NOT USE sticker. Apparently there had been some “Red Face, expensive, incidents”.
Every aircraft I flew with an OEI training switch had a big DO NOT USE sticker. Apparently there had been some “Red Face, expensive, incidents”.
Doesn't look that unusual.
There can be issues with "rounding errors" in the way the airframe display looks at partial cycles which can accumulate versus the way the DCU counts.
The "algorithm" in the EEC does take into account the time between start and fly amongst other parameters. EMS "fast starts" will eat cycles more.
DCU record is written to the EEC on boot and at end of flight calculated and written back to the DCU. The "write" occurs at a particular N1 speed and on early 206's it was set too low for the folks that turn the battery off before the N1 had stopped and would corrupt the data. All fixed these days.
If you are really keen I think the algorithm might be in the EMM.
IM = Impeller
CT = Compressor Turbine
PT = Power Turbine
"Training Mode" - during the introduction of the EC135P2 with the PWC 207 (206B2) there was a period where the switch controls for "TRAINING MODE" were fitted but not the software or wiring. It was placarded as INOP or maybe not.
i.e. Factory training carried out with new customer and as the customer was unfamiliar and the training pilot was possibly too complacent TRAINING selected but not confirmed with Delta with "T" and TRAIN IDLE on the CPDS display and cross checking digital values remain similar. Training continues until after a few flights ENG EXCEED warning. Turns out they were using real OEI limits! Two new engines before handover to the customer.
This was also the period before the flight stops were fitted to the twist grips on the EC135 to keep them from being rotated out of the N detent. Last thing a lot of pilots from "old style" machines do is check the throttles are both OPEN. i.e. Bell 212/412. Result - both engines revert to MANUAL and do as requested. OVERSPEED.
Don't get in a position in TRAINiNG MODE where the OEI N1 tops out and Nr droops to where it initiates "recovery" back to normal as you will easily get a torque exceedance. Being above OEI training weight limits contributes.
There can be issues with "rounding errors" in the way the airframe display looks at partial cycles which can accumulate versus the way the DCU counts.
The "algorithm" in the EEC does take into account the time between start and fly amongst other parameters. EMS "fast starts" will eat cycles more.
DCU record is written to the EEC on boot and at end of flight calculated and written back to the DCU. The "write" occurs at a particular N1 speed and on early 206's it was set too low for the folks that turn the battery off before the N1 had stopped and would corrupt the data. All fixed these days.
If you are really keen I think the algorithm might be in the EMM.
IM = Impeller
CT = Compressor Turbine
PT = Power Turbine
"Training Mode" - during the introduction of the EC135P2 with the PWC 207 (206B2) there was a period where the switch controls for "TRAINING MODE" were fitted but not the software or wiring. It was placarded as INOP or maybe not.
i.e. Factory training carried out with new customer and as the customer was unfamiliar and the training pilot was possibly too complacent TRAINING selected but not confirmed with Delta with "T" and TRAIN IDLE on the CPDS display and cross checking digital values remain similar. Training continues until after a few flights ENG EXCEED warning. Turns out they were using real OEI limits! Two new engines before handover to the customer.
This was also the period before the flight stops were fitted to the twist grips on the EC135 to keep them from being rotated out of the N detent. Last thing a lot of pilots from "old style" machines do is check the throttles are both OPEN. i.e. Bell 212/412. Result - both engines revert to MANUAL and do as requested. OVERSPEED.
Don't get in a position in TRAINiNG MODE where the OEI N1 tops out and Nr droops to where it initiates "recovery" back to normal as you will easily get a torque exceedance. Being above OEI training weight limits contributes.
folks that turn the battery off before the N1 had stopped
TO ENSURE ENGINE CUTOFF, HOLD THROTTLE IN CLOSED POSITION UNTIL N1 DECELERATES TO 0 AND TOT IS STABILIZING. DO NOT TURN BAT SWITCH OFF UNTIL N1 IS 0 AND TOT STABILIZED
Prior to switching electrical power OFF ensure engine NG values are at 0%.
