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Old 9th Apr 2014, 21:40
  #174 (permalink)  
Creampuff
 
Join Date: Nov 2000
Location: Salt Lake City Utah
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Serious question: why doesn't whoever writes the POHs advocate LOP?

Second, if I attend the course and install engine monitors, do they come with an AFM supplement or similar that would make it legal to operate LOP in defiance of the stated procedures (CAR 138).

Cheers
Hi scavenger

Some POHs do include LOP power settings. But let’s assume none do and the effect of CAR 138 and all POHs is that LOP operations are illegal and your gonna’ go to gaol if you’re caught running LOP.

An engine monitor will tell you lots of useful information when the engine is running ROP. It will tell you what plug is fouled. It will tell you what injector is partially or completely blocked. It will tell you what exhaust valve is sticking. It will tell you whether all cylinders are at a comfortable margin below red line during the climb (rather than just the cylinder that happens to drive the single sensor that drives the steam driven CHT gauge). It will tell you if a cylinder is suffering pre-ignition and you may have sufficient time to take action to save your engine and your aircraft.

Most importantly for those who don’t want run at settings that dare not speak it’s name, you’ll know that all your cylinders are actually ROP, and far enough ROP that you are not beating your engine to death. (That’s what cracks me up about all the LOP disaster and illegal brigade. Many of them are probably already operating LOP, or at least with some of their cylinders operating LOP, while being blissfully ignorant of the fact. Most of the damage that yr right sees is due to not running the engine far enough ROP, or bad manufacture or bad fitment.)

In short: An engine monitor will assist you to operate safely ROP, and demonstrate to you, with actual real-life data why, for example, it’s really, really silly to run an engine at 25 degrees C ROP, and it’s really, really silly to set 25/25 in the climb on a standard CMI engine. It will also assist you to diagnose faults and save you lots of time and stress. Compare: “The lower plug on 3 is fouled”, with “The engine ran rough on left mag”.

And, if you have an engine monitor and a fuel/induction system that result in balanced F/A being delivered to each cylinder, one day, while you’re at 8,500’ and mum and CASA aren’t around, you can grab that red knob and pull it while ogling those EGT bars. (The APS guys will even teach you how to do it with your eyes closed!) And watch the CHTs go down on you ...
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