Roger Roger
Bottom of the list
Just start with some steep turns.
[Question] Hand on the throttle at ALL TIMES?
- Thread starter kingck
- Start date
n57flyguy
Well-Known Member
Aerobatics scare me
TwoTwoLeft
o- - - - - - -l
I find rolling turns work the best. Gets everything done at once and eliminates that whole high/low wing issue...
Roger Roger
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Airplanes scare me.
Roger Roger
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The airplane doesn't know the difference. It's all in your head.
🦈💜
Well-Known Member
Yes, but that is where my navigational instruments are located!
Sometimes they're rendered inop by said water, and I, for one, will turn around. Often first.
"Wimp of Alaska"
-Fox
n57flyguy
Well-Known Member
I was actually reading an article about "shock cooling" and the effects rain has on cooling the engine and heat dissipation as a result.
Yes I said shock cooling on purpose.
Roger Roger
Bottom of the list
I've watched the instruments then entering or exiting rain for changes in CHT (piston) or EGT (turbine). So far nothing noticeable.
n57flyguy
Well-Known Member
I didn't think it was of huge difference. I have just got into the world of HP airplanes and I keep hearing "don't shock cool it" and can't really find a good case for what shock cooling is. I keep hearing that cylinders will crack, but I would be more worried about sucking a valve personally.
USMCmech
Well-Known Member
Lycoming considers CHTs dropping 50c in under a minute "shock cooling", and so would I.
Having said that, do you know what you have to do to get CHTs to drop almost a degree per second? It's simply not a concern for any conventional point A to point B flying.
The biggest variable in engine cooling is airflow through the cowling, not engine power. Therefore, your airspeed and cowl flaps have the most control over engine cooling. I'm currently flying 6 different HP airplanes and I have the same descent profile for all of them. Dial in a -500 FPM descent with the autopilot and bring back the throttle as far as necessary to maintain the cruise airspeed.
n57flyguy
Well-Known Member
Shutting it down is probably as close as you'll get to shock cooling!
Does that descent profile coincide with 1" per 1,000 ft.?
USMCmech
Well-Known Member
Nope, I don't even bother.
If I'm at 8,000 above my destination, I wait till the GPS says I'm 16 minutes out and dial in -500 FPM. Pull the power back to whatever MAP keeps me from gaining extra speed in the descent. In the Matrix, CHTs are typically around 350c in cruise, and they are in the 320s by the time I am in the pattern.
In just about any airplane, that procedure will work fine.
Roger Roger
Bottom of the list
I have fully programmable VNAV. The shiznit.
n57flyguy
Well-Known Member
I like it, and I will have to try it. In the Matrix for example, are you going the same speed downhill as in cruise?
USMCmech
Well-Known Member
Yes I stay at the same airspeed (and therefore cooling airflow) during descent. I've watched CHTs carefully and there is only a modest cooldown despite pulling about 7" MAP at the top of descent. Again, I've carefully watched the CHTs when doing this, and there is only a modest drop over 3-5 minutes.
I'm not saying aluminium cylinder heads can't crack from rapid cooling, but it's not anywhere near the bogeyman that it's made out to be.
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Henry Coanda
New Member
Yep, during cruise it's pointless unless something's wrong with the aircraft.