Man this 172 is going to require some careful planning in IFR. And remember leaning with the EGT gauge? 50F rich of peak lean…hopefully holds up for the 172…
That MEA on V120 is no joke…
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Whew…finally level 11,000’ and receiving Pangborn VOR…only 40 miles to go…this C172 the TOC (Top of Climb) = TOD (Top of Descent)…
OK - Bush 172 is back in KEAT and available…! (I guess you have to remember to BOOK IN at the end of each flight if you are leaving the plane?)
Old school stuff I guess? Good friend of mine flies 73’s for a “major US carrier”; I told him about my granddad one time, that he flew “BJ - Before Jets”. His comment was, to paraphrase, “Yeah, back when you had to fly the airplane”. I want to do it for learning’s sake, but glad they don’t do it that way anymore.
That went right over my head.
Hmmm. I’ve not tried that yet but I’m sure it is easily missed.
So there is an EGT (Exhaust Gas Temp) gauge on some piston aircraft. As you lean the engine as you climb (lessening the fuel because there is less oxygen concentration) the fuel mixture becomes more lean…burning hotter and ostensibly, cleaner. A typical technique (but always follow the POH!) is to lean until the EGT peaks, mark that, then enrich by 50F and that is where you want to operate the engine. So 50F rich of peak lean.
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Man running peak of lean is huge on the fuel savings. Can easily chomp down double at max fuel flow haha.
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Ah. I may have been doing this, or nearly so, just by intuition; I’ll increase mixture (more rich) till I see the RPM ‘sag’, then lean until it maxes out again, then lean it again, slightly, til it just starts to drop. Watching the fuel flow and temps.
So by, 50F you mean the temperature as your guide. Cool.
I’m learning something all the time with this stuff. One reason I really enjoy it.
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I’ve never leaned a real aircraft engine in my life so take the below with that in mind…
So there’s “rich of peak” and “lean of peak”. Peak is where the EGT is the hottest (and hence cleanest) for the conditions.
The rule of thumb for a typical GA plane is to go 50f rich from peak, as the additional fuel in the mixture will help cool temperatures and running rich of peak doesn’t easily damage anything.
The leaning process would start from full rich (assuming taking off near sea level): as you climb / reach cruise, you set up the engine for the desired cruise (RPM and manifold pressure), then start leaning the mixture from rich to lean, watching the EGT gauge.
The needle goes higher as you lean, then starts going lower again as you keep leaning. The highest point is the “peak“, or “peak lean“. Once you’ve found the peak, to go “rich of peak”, you go back towards rich (where you started from) by 50f on the gauge.
So I guess what you’ve been doing is leaning “lean of peak”, if I’ve understood correctly.
Lean of peak also achieves lower temperatures through more air and reduction in engine power.
Lean of peak can work really well for endurance, however not all engines can handle running lean of peak and you can break expensive things if you do it wrong. The engine has to be injected, not carb, and generally has to have temperature (CHT/EGT) probes for every cylinder so you don’t accidentally run one cylinder at peak without knowing it.
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Thanks for that, really appreciated. There’s a few things I wonder about all the time. This is one. And temperature (EGT) is what I’ve been keeping an eye on when I “play with the knobs & levers” 
But it’s just a WAG on my part. The above makes sense.
EDIT: The only thing I knew about the rich & lean was from my days of bike riding; When I toyed with taking one out for track days, well, one thing led to another…then I’m playing with the jets, etc, to compensate for the altitude (lived at a mile high). So I understood that part of it. But not so much how it influenced temperatures. Just seems much more dramatic in aero-planes.
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Use caution when loading material at KEAT since we have several outbound jobs sitting idle. Would hate for anyone to fly 500 miles with DVDs instead of Shrimp… I guess you can untick VA if you are working your own company…
This is the reason I love flying the A2A aircraft in p3d, you have to fly them right and when you do the rewards are great.
What happens if you transfer a job to the VA and it doesn’t get done?
I don’t want to accept the job if it isn’t going to be completed. I don’t want a rep hit, and I don’t want MAD to take one either.
Yup. Yesterday there were two Narcotics jobs. I needed to make sure that I delivered the correct box
Probably a rep hit for the VA. I am only transferring the job before I run it.
Not a huge fan of this system. Would much rather it generated jobs for the VA on its own that we could accept or not
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I does both, right? I mean, if no one transferred jobs from their company to the VA, the VA would still have a list of potentials to choose from. Transferring is optional just to bring a little more cash over to the VA.
No I don’t think so. I think it’s only jobs we transfer.
Yeah, I don’t understand why the VA isn’t generating jobs for the Cessna 172…
I was really hoping it would generate VA specific jobs in the VA cargo job list. But, I have noticed that jobs from KEAT have started to appear in my available cargo jobs!
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