Tis true!
Had to come out eventually
The C130J is getting through turbines somewhat quicker than it should
Basically they are being run too hot. We cruise at a detented power setting of MCP (max continuous power) but it would seem that this is a bit too warm for a healthy turbine life.
Apparently they need to run about 30degC cooler to preserve their life. Cruise EGT is about 740degC so it would appear that a new cruise power setting needs to be found. Unfortunately all we have in the ODMs are High Speed Cruise and the mind-numbing Long Range Cruise.
Until data figures can be produced for an "MCP - 30" Speed Cruise setting the Release to Service has been amended such that Long Range Cruise is the power setting to be used. This can add over an hour to a flight back from Cyprus....
As an aside, if Long Range Cruise is flown properly then the aircraft should always be at it's cruise ceiling. This leads to a situation whereby, in the high 20s/low 30s FLs the power setting required is MCP, as near as dammit. Couple this with the lower airspeeds associated with LRC one can end up spending longer at MCP than if one was High Speed Cruising at a lower altitude. Ho hum.
I imagine it'll take about eight thousand years for Qinetiq etc to produce new ODM data (and then stress test the pages to 90G and -243F) and so hopefully an interim solution may be found. Cruising at MCP - 30 deg doesn't have a major impact on flight times; back from Cyprus it would add about 10 minutes over a HSC plan. Whilst there is no data for MCP - 30 fuel flows etc one can just run a LRC fuel plan and use that as a Red Line. Once at cruising level actual IAS and Fuel flow can be stuck in the CNI to give accurate ETAs and fuels. If you hit the red line, go LRC, just as per the SOP for HSC.
Not that I'm suggesting you do that of course. R to S is the law
and the PMA sees all
Coincidentally, the K had a similar problem when it came into service. Cruise power was originally, I believe, 1010deg. This was knackering engines so was reduced to 932deg (?). I think ultimately the additional costs of fuel, extra flight time, long crew duty etc etc outweighed the costs of engines so it was upped to the happy medium of 985deg.
At least that's what bloke down the pub said.
I shall now prepare myself for a weekend standing in front of one telling the punters 'ow bleedin' marvellous the J is
Cos it is
