Michael wrote:
IMHO shock cooling is largely over-hyped and no where near a problem as some seem to think.
Shock cooling I do not believe in. I was referring to cabin pressurization. If you pull the throttle back at FL250 in your Mablibu, your lips are going to turn blue…
Martin wrote:
@achimha I would be interested in the leaning technique and temperatures (especially CHTs).
A P210/Malibu is generally flown with a lot of power (70-75%) and the CHTs are high because the cooling air mass is very limited in the FL200-250 range. Nothing you can do really. In this scenario, a big bore turbocharged Conti will eat through cylinders, that’s a known fact in the industry. You don’t fly those airplanes at 55% BHP wearing a fur coat and an oxygen mask in your pressurized cabin.
Cylinders of big bore turbocharged aircraft engines are consumables. If I had such an airplane I’d have a couple of ready cylinders in the hangar …
Cylinders of big bore turbocharged aircraft engines are consumables. If I had such an airplane I’d have a couple of ready cylinders in the hangar
I have had this old debate, of whether replacing a cracked cylinder means the engine did not make TBO, with loads of people.
Predictably I don’t end up in the same camp as those who think it’s fine to discover, usually at the Annual i.e. once a year, that one or more of their cylinders might have come right off when above the Alps, etc.
For me, flying already has enough excitement to keep me on my toes 
It reminds me of some spy novel in which a cold-war-USSR finance minister always flew Swissair, never Aeroflot, saying he does not believe in betting against known odds. I did 189hrs in 2014; much of it in places where you want to really believe in the lump up front.
Regarding cylinders as “consumables” is an often quoted phrase, especially within the turbocharged community, but to me it represents a totally unacceptable attitude to risk.
I don’t see why a given IO-550 engine type should have a higher catastrophic failure rate in an SR22 than in something else. I would expect a higher rate of component wear due to the single lever bodge which – at Eurocontrol levels i.e. wide open throttle – forces a higher RPM than a 3-lever pilot would sensibly fly with (e.g. 2400 v 2700). But any supporting data will be hard to come by because it takes so many years to reach TBO that it almost never happens within the ownership of one person, and that makes it impossible to make allowances for differences in engine management.
FWIW Mike Busch has said in one of his articles that there is no catastrophic failure rate difference between C and L. Both have issues but different ones. L has the crankshaft vulnerability to corrosion in low usage, for example.
That’s not the way the single lever works. You can influence both the MP and the RPM. When you pull back from full throttle you first reduce RPM ONLY and then behind a certain position MP is reduced. Of course you can fly 2400 rpm with the highest possible MP.
There is NO higher wear becasue of the single lever system.
I wasn’t aware of that. However I recall flying with two pilots in an SR22 (non T) who were not aware of this, and I recall discussions both here on EuroGA (e.g. here) and in the non-private section of COPA regarding that single lever STC where the ability to cruise at a lower RPM and get better MPG was discussed extensively, and this was never previously raised.
That’s definitely true … unfortunately there’s a percentage of Cirrus pilots who never understood the system.
So… that STC is completely fake and nobody noticed?
This is the Power lever assembly (photo at Cirrus Factory, 1998). This is the SR20 version, the SR22 one looks a bit different. The upper control is for the RPM the lower controls the MP
achimha wrote:
A P210/Malibu is generally flown with a lot of power (70-75%) and the CHTs are high because the cooling air mass is very limited in the FL200-250 range. Nothing you can do really.
That power sounds right. One thing you can do is not to fly that high when not necessary. There is a small modification for Malibu/ Mirage that improves cooling. Improved reliability is worth to me some operational limitations. And leaning can help with the temperatures.
Peter wrote:
I wasn’t aware of that.
Flyer59 is right. It’s no secret. However, that modification should give you more control.
