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Now, that's a nice cold start

Posted: Sun Dec 29, 2019 4:40 am
by Colonel
W100 is my winter-weight oil, laced with Camguard.  I'm after the kid to keep the RPM
low after start - he's not a four bar, for God's sake, trying to wreck a pair of C421 engines:

[img width=500 height=82][/img]

Nice!  That's not easy, with a composite-blade prop - no flywheel effect. 

I really, really hate it when people hit a cold engine with RPM, and it's not just about circulating oil.

Re: Now, that's a nice cold start

Posted: Sun Dec 29, 2019 1:52 pm
by Liquid Charlie
I am horrified when I see the way most pilots handle engines. I live on the lake and it's like scratching a blackboard. Ramming power on so fast the prop governor can't keep up. I guess it's a throwback from my round engine days but cold starts and ticking over at 4 to 5 hundred rpm until things smooth out and then a slow increase to 1000 rpm in increments. I had an old bush pilot explain to me once saying it's not how much power you use at takeoff but how you apply it. The shock cooling and props driving engines are the worst and will cause all sorts of failures. I got a direct entry left seat on a cv44 because that company pilot pool of flat engine drivers were destroying the R2800's and they wanted pilots with large round engine background,

RPM loss of control on start is also very bad, especially in lycomings with damage to crankshaft thrust bearing. Just go to your local flight school and that is the way they are taught. It is the standard sound of pulling throttle back after start because the rpm just shot up to 1500 plus -- damn - engines will start with throttle closed,

Re: Now, that's a nice cold start

Posted: Sun Dec 29, 2019 4:36 pm
by Colonel
Round engines MUST run at minimum RPM, barely ticking over, for at least a few minutes after start.

I know a guy, used to start up a T-28 like a car and drive off with RPM.  Sure enough, the engine
made metal and was destroyed.  He didn't care, because he had enough money that his time was
worth destroying engines regularly.

It's not just the oil circulation.  The engine is constructed with different metals, and as a result the
clearances change with temperature.

Just because an engine will take the throttle, doesn't mean it's ready to go.  All that means is that
the fuel is atomizing.  Doesn't say anything about the engine internals.  Hell, you can start an engine
with ether at -20C, with zero - or negative! - internal clearances.  Don't ask.

One trick is to run it for a minute then shut it down, and let it sit for a couple minutes, and let the
heat from the cylinder heads conduct to the bottom end.

Another trick of mine is on final, don't advance the props until they're at the fine pitch stops.  I hate
it when you hear that ZIIIIIIINNNGNGNG!!!!! on final as the pilot frantically jams the prop controls
forward for landing and they over-rev.  Can you say, "De-tune the counterweights", boys and girls?

https://www.faa.gov/documentLibrary/med ... 20-103.pdf

Commercial pilots in Canada require EIGHTY FUCKING HOURS of ground school, and they spend
most of it on completely useless crap.  Too bad that in EIGHTY FUCKING HOURS they don't have
time to read the three and a half pages in that FAA AC.

Re: Now, that's a nice cold start

Posted: Sun Dec 29, 2019 6:09 pm
by Nark1
I see it all too often here in Wisconsin.

Engine start, 1500+RPM taxi.  Takeoff right away. 
The neighbor in his RV will surely scratch his head why his O-360 isn’t coming close to TBO (don’t get me started with that cockamamie idea).

Whereas I’m the guy sitting for 20+ minutes waiting to do a runup.  My oil analysis is spectacular after 1100 SMOH of which I have 300 of it. 


Re: Now, that's a nice cold start

Posted: Sun Dec 29, 2019 7:02 pm
by Colonel
Making metal in your engine is generally not a good idea.  This is not my engine:

[img][/img]

[quote]Engine start, 1500+RPM taxi.  Takeoff right away.[/quote]

[img]http://culturecrossfire.com/wp-content/ ... 8/Augh.jpg[/img]

Putting my money where my mouth is, here is my last start:

[img width=500 height=244][/img]

Not as good as the kid's, but ok.

Re: Now, that's a nice cold start

Posted: Sun Dec 29, 2019 10:06 pm
by Nark1
I’m trying to download the data from my EDM 830, but I can’t figure out how to pull it from the unit, to the USB.

I’m in search for the big manual, not just the quick reference one. 

Re: Now, that's a nice cold start

Posted: Sun Dec 29, 2019 10:13 pm
by Colonel
Once you get it on the USB stick, you need some software to import the CSV file and create charts.

Also, you can just upload the CSV to Mike Busch's website.

PS  Google says to do this:

[quote]1) Plug in your USB Download Box to your cigarette lighter, and the EDM downloading port.

2) Set the EDM to ‘Dump New’ or ‘Dump All’.

3) Tap the ‘Step’ button on the EDM to start downloading.[/quote]

Re: Now, that's a nice cold start

Posted: Sun Dec 29, 2019 11:11 pm
by Nark1
My issue was being a bitch. 
I wasn’t seating the thumb drive enough. A little jiggle and the prompt to download came up.

Imagine that. 

Re: Now, that's a nice cold start

Posted: Mon Dec 30, 2019 2:09 am
by Nark1
I'm nerding out on this pretty good.


Re: Now, that's a nice cold start

Posted: Mon Dec 30, 2019 2:38 am
by Eric Janson
This applies to jet engines as well.

We can't control the idle RPM but the manuals say 3 minutes MINIMUM at idle power before advancing thrust to allow thermal stabilisation of the engine.

3 minutes idle MINIMUM after landing for the same reason.

There is even a procedure for a 10 minute idle time to reduce peak EGT on take-off.

This works very nicely - no exceedances on my flights this Summer taking off at +46C. All 4 engines were boroscoped recently with no findings.

CFM56 is probably the most reliable jet engine ever built.