Engine failure

OkieAviator said:
Should also note this 172 doesn't have an avionics switch
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That is a pet peeve of mine, the checklists that are illogically written and not relevant to the airplane you are flying. Someone mentioned in another thread that they write their own logical checklist.. I agree with that and it's a good practice. The owner of the plane I rent has his own checklists and they're pragmatically designed and flow well

OkieAviator said:
Which is another example of why you can't blindly follow a checklist
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I tend to agree with this, you need to think about why the checklist is asking you to do the things you do... but I do think it's bazaar that it doesn't say something like "return to idle" or "return to 1,000 rpm" - simply because it tells you a few steps above to advance to 1,700, but then never tells you to go back to the earlier state, the logical progression is that you leave it at 1,700 RPM. For example the after landing checklist specifically says "retract flaps" so I think the omission is strange
 
caramon13 said:
Every checklist I have used has a check idle step as part of the last steps in run up.
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WannFly said:
The mixture cut off and idle check is a part of the checklist, at least in the cessna checklist at my school
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Very interesting. We have never had an Idle Check as a part of any checklist (e.g. Normal Procedures) for any of our Club aircraft (C152s, PA28s, C172s, M20Js) in the 22 years I have been flying with our Club. Now, I am curious, and will ask our (long time) CFI and our A&P if there is a reason for that.

Now, our checklists do include returning the throttle to 1000 rpm after initial start-up, after run-ups, after landing and clearing the active runway but before taxiing, before shutdown, etc. IOW, 1000 rpm (not idle) is the default throttle setting unless power is being applied. But, that is really quite a different situation from what happened to the OP, where the throttle was pulled back to Idle, and the engine quit. While it sounds reasonable to consider including an Idle check, it is not clear from the OP's description that doing an Idle check on the ground before take-off would have accomplished anything, because it is not clear when the idle set screw 'fell' out.

I am also curious about the experience of those who do include an Idle check - have any of you ever experienced what the OP encountered? Have you ever run an Idle check, and had the engine cut off and refuse to restart?
 
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Another thing to consider: When you pull the throttle back to idle on an NA engine, carb-heat is on. So, if you really want to do an idle check, you need to check it with carb heat on, that's not in the checklist either.

Here's how I was taught:

1 Engine: 1700 RPM
2 Mag check: Left-both-right-both (check for....)
3 Carb heat: on (check for...)
4. Throttle: idle (check for smooth idle with carb heat on)
5. Carb heat: off (engine rpm slight increase, smooth idle)
6. Throttle: 1000 RPM....

Colliam7 said:
....I am also curious about the experience of those who do include an Idle check - have any of you ever experienced what the OP encountered? Have you ever run an Idle check, and had the engine cut off and refuse to restart?
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Yes! I had a flight review from an independant CFI with a Super Decathlon who's throttle was not rigged properly. I pulled the throttle to idle and rounded out on the very first landing and the engine died. He said something to the effect that it was no problem, he'd just learned how to live with it. I told him his throttle needed to be rerigged (it was stiff as hell in addition to not idling). He said, "nah, they're all like that."
 
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I think the reason most of the checklists don't have an idle check is because if you're about to launch into IMC, you're going to lose vacuum while you do it, and perhaps spin down a crappy DG and make it precess. Not that I believe a few seconds of idle will spin it down much (or else it's useless and will precess like crap anyway), but I could see someone trying that argument.
 
OkieAviator said:
Which is another example of why you can't blindly follow a checklist. Should also note this 172 doesn't have an avionics switch so for some that might confuse them when they can't find it.
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It did when it came from the factory.

Why would someone remove that? Granted, it's not THAT much effort to turn off everything, but it seems pointless to remove.
 
MAKG1 said:
It did when it came from the factory.

Why would someone remove that? Granted, it's not THAT much effort to turn off everything, but it seems pointless to remove.
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I don't thing the Cessna 172N (1977-1981) came with OEM avionics master switches. I seem to remember installing them for our flying club. Big debate at the time on using a cheap switch and a relay vs. using a properly rated DC switch.
 
MAKG1 said:
It did when it came from the factory.

Why would someone remove that? Granted, it's not THAT much effort to turn off everything, but it seems pointless to remove.
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I thought the point of an avionics master was to prevent damage to the avionics during engine start.
 
MassPilot said:
prevent damage to the avionics during engine start.
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I've been told the same, to prevent power surges, etc., but I think the idea with the lack of a switch was just to shut the radios, etc., off individually
 
wilkersk said:
I don't thing the Cessna 172N (1977-1981) came with OEM avionics master switches. I seem to remember installing them for our flying club. Big debate at the time on using a cheap switch and a relay vs. using a properly rated DC switch.
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that would have been my vote all that way. KISS
 
jsstevens said:
Since I just switched clubs and instructors...

In the old club where the main training plane (C-172C) was owned by the instructor, we ran the plane at 1000RPM on the ground, leaned. He was adamant about keeping the RPM up, and it taxied rather briskly. He was also adamant about using the brakes sparingly. Run up check was pretty much what the manual said, no specific idle check (and in fact, I just went back to 1000 RPM after the checks).

New club, new instructor (who doesn't own the planes) and a C-172P. He had me do an idle check post run-up. And kept telling me to slow down on taxi. I mentioned "I hate riding the brakes." He said you just have to. (He's not buying the brakes.)

Upon reflection, I think the idle test is a good idea and I'm adding it into my mental checklist...

John
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Why do u have to ride the brakes during taxi? U can keep it around 800-900 rpm and won't even have to touch the brakes. I even pull the throttle to idle when I approach a turn so that I don't have to ride the brakes

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The checklist at my school is from checkmate for what it's worth. It also have a GUMPS check, however I don't check for undercarriage , it's already wielded. Or may be they mean check if the tires are there...dunno

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WannFly said:
The checklist at my school is from checkmate for what it's worth. It also have a GUMPS check, however I don't check for undercarriage , it's already wielded. Or may be they mean check if the tires are there...dunno

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Yeah, GUMPS is kinda silly on a 172. It's also missing the carb heat, which you really want on a carbureted 172 at low power, even on a nice day.

Let's see. "G" is "gas." What exactly are you looking for and how is it actionable? Some airplanes have a tank you can switch, but not 172s. Like, 206s or most low wings. Some also have a boost pump that may be needed for a go-around. I suppose if you've had the selector on "left" you should switch it to "both" (but you really should have done that prior to decent). "U" is undercarriage. Real important if you have retractible gear. Stupid if you don't. "M" is "mixture. Yes, you need this, usually. "P" is "prop." Fixed pitch? I suppose you can check it's still there... CS needs to go forward. Safety belt/switches? OK.
 
MAKG1 said:
Yeah, GUMPS is kinda silly on a 172. It's also missing the carb heat, which you really want on a carbureted 172 at low power, even on a nice day.

Let's see. "G" is "gas." What exactly are you looking for and how is it actionable? Some airplanes have a tank you can switch, but not 172s. Like, 206s or most low wings. Some also have a boost pump that may be needed for a go-around. I suppose if you've had the selector on "left" you should switch it to "both" (but you really should have done that prior to decent). "U" is undercarriage. Real important if you have retractible gear. Stupid if you don't. "M" is "mixture. Yes, you need this, usually. "P" is "prop." Fixed pitch? I suppose you can check it's still there... CS needs to go forward. Safety belt/switches? OK.
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Yeah P doesn't make sense either, though there may be a 172 with CS. I fly the SP model, so no carb heat for me. I think every checklist should be custom made for that plane instead of generic ones.

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WannFly said:
Yeah P doesn't make sense either, though there may be a 172 with CS. I fly the SP model, so no carb heat for me. I think every checklist should be custom made for that plane instead of generic ones.

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There are a few 172s that have CS props. Most of them don't.
 
On a BFR some years ago an instructor told me to pull the throttle all the way to idle after checking mags and carb heat. When I went to first push the CH in he said 'no leave it - I want to see it won't quit'. I do it every time now and ensure that the motor doesn't die and when CH is removed, that power is smoothly restored.

I've also added items my own items to my checklist like "Tow Bar - Stowed" and "Fuel caps - On & Tight".
 
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