201er Posted October 1, 2018 Report Share Posted October 1, 2018 (edited) Biggest take away from the Mooney Summit, a bruised leg! We stayed the rest of Sunday and went to Gulf World and my wife got to ride a dolphin. Departed early this morning for one of the smoothest and most uneventful cross countries ever, except...!!! Doing my routine preflight I usually spin the prop through one or two turns. I always treat it like hand propping and push and get out of the way. Well, being Florida, there was a lot of rain and a deep puddle right in front of my plane. Trying not to get my light sneakers wet before the flight I huddled in close to the plane. As I flicked the prop down, it swung around and clubbed me right in the left knee! Ouch. There wasn’t any fuel or spark in the system so luckily it couldn’t have fired. But man that hurt. Narrowly missed smashing the phone in my pocket as well. Went back in the FBO and got some ice. Not to punish the prop but for the bruise. Still hurts tonight. Learned not to try to shortcut things like this. Either stand in the normal position even if it means being in a puddle or maybe move the plane some. But don’t try leaning closer to the prop because after it goes down, then it flings over! And it’s bigger and harder than it seems. After icing it, laughed it off and took a couple re-enactment photos. Edited October 1, 2018 by 201er Quote Link to comment Share on other sites More sharing options...
DualRatedFlyer Posted October 1, 2018 Report Share Posted October 1, 2018 Why do you rotate the prop through before flight? 3 1 Quote Link to comment Share on other sites More sharing options...
201er Posted October 1, 2018 Author Report Share Posted October 1, 2018 1 minute ago, DualRatedFlyer said: Why do you rotate the prop through before flight? Check that it feels right, impulse coupling working, and I think it eases things up for the starter because it has been pulled through a little and the initial turn will go a little easier. Especially in winter. Quote Link to comment Share on other sites More sharing options...
Hank Posted October 1, 2018 Report Share Posted October 1, 2018 3 minutes ago, 201er said: Check that it feels right, impulse coupling working, and I think it eases things up for the starter because it has been pulled through a little and the initial turn will go a little easier. Especially in winter. I do this in the winter, after unplugging the engine heat and pulling out of the hangar. Generally two revolutions. During warm weather, I just get in and start the checklists. Quote Link to comment Share on other sites More sharing options...
1964-M20E Posted October 1, 2018 Report Share Posted October 1, 2018 Glad it was just a bruised knee. As to why pull the prop through I was told a similar tale that it loosened things up for the starter. Maybe an OWT. I still do it make sure the engine will turn over if not then I'm not going l flying that day and no use in finishing the pre flight and dragging the plane outside. Quote Link to comment Share on other sites More sharing options...
DualRatedFlyer Posted October 1, 2018 Report Share Posted October 1, 2018 Interesting. I always heard that it removes the film of oil on the cylinders and cam followers and that it can cause excessive wear when starting. Could of swore I read that in a Lycoming SB once upon a time. I'm no expert though. 1 Quote Link to comment Share on other sites More sharing options...
tony Posted October 1, 2018 Report Share Posted October 1, 2018 48 minutes ago, 201er said: Check that it feels right, impulse coupling working, and I think it eases things up for the starter because it has been pulled through a little and the initial turn will go a little easier. Especially in winter. Do that with a broken P lead and it might just be the last time. I would like you to reconsider doing this in the future. I really don't think its buying you any increased safety. 10 Quote Link to comment Share on other sites More sharing options...
MB65E Posted October 1, 2018 Report Share Posted October 1, 2018 I’ve only had one kick on me. It’s the real deal. I’ve never seen 3 blades on a T182 spin so fast! “clear of the propeller airscrew arc!” Ouch! -Matt 1 Quote Link to comment Share on other sites More sharing options...
aviatoreb Posted October 1, 2018 Report Share Posted October 1, 2018 This seems like an OWT is encouraging what may well be a (slightly but unnecessary) dangerous practice. 5 1 Quote Link to comment Share on other sites More sharing options...
LANCECASPER Posted October 1, 2018 Report Share Posted October 1, 2018 In 33 years of flying I’ve done this exactly zero times. 8 1 1 Quote Link to comment Share on other sites More sharing options...
RLCarter Posted October 1, 2018 Report Share Posted October 1, 2018 Never been smacked (knock on wood) by one, but I have raised up into a few hard enough to rotate the engine 15 to 20 degrees. I agree with others, turning the prop by hand should only be done when absolutely necessary. As far as wiping the oil off things, it wont wipe anymore than actually starting the engine. Radial guys pull their motors through to ensure the bottom cylinder(s) haven't filled with oil and hydro-locked the motor...should have a nice bruise by morning if not already 1 Quote Link to comment Share on other sites More sharing options...
ilovecornfields Posted October 2, 2018 Report Share Posted October 2, 2018 So, no clear benefit but it might maim or kill me? I guess I’m still undecided on this one... Seriously, I have seen someone get critically injured turning the prop over and in my mind it’s not worth it. 2 Quote Link to comment Share on other sites More sharing options...
Guest Posted October 2, 2018 Report Share Posted October 2, 2018 In more than 30 years of maintenance I’ve hand swung more than a few airplanes to get them started with a dead battery. I’ve been hit in the arm by one propeller while doing a compression check, and worst of all I’ve had one start and run in the shop while checking a starter with the mixture in ICO. It ran for a few seconds but it seemed and eternity. We sometimes don’t give propellers the respect they deserve. Be careful. Clarence Quote Link to comment Share on other sites More sharing options...
TNIndy Posted October 2, 2018 Report Share Posted October 2, 2018 A pilot was killed in Cleveland TN doing this in July. It was a Cessna 182. Key was in his pocket 1 Quote Link to comment Share on other sites More sharing options...
nels Posted October 2, 2018 Report Share Posted October 2, 2018 (edited) Turning the engine over just one revolution would put the suspended oil from the bottom of the cam lobe to the top of the cam where it is free to run back over the cam lobes while the engine is cool. Edited October 2, 2018 by nels Quote Link to comment Share on other sites More sharing options...
Yetti Posted October 2, 2018 Report Share Posted October 2, 2018 (edited) so if it had started what would have happened? I generally ask this question before I do most silly things like running a chain saw or flying or rigging things for lifting. The OP said he was treating it like a hand prop. But the tail was not tied, the brakes were not set, the wheels were not chocked. there was not a pilot in the plane on the brakes. Lucky to get away with a bruised leg. My plane starts like crap if I pull it through. Edited October 3, 2018 by Yetti 1 Quote Link to comment Share on other sites More sharing options...
Tommy Posted October 2, 2018 Report Share Posted October 2, 2018 The risk to benefit ratio of this "checklist" item seems high. I hope you always do a mag cut off check before shut down. I had flown quite a few different planes now and AFAIK no manufacturers call for a "prop turning" check during the pre-flight. Sometimes, though rarely, adding personal checklist items can be as dangerous as omitting the official ones... 1 Quote Link to comment Share on other sites More sharing options...
Tommy Posted October 2, 2018 Report Share Posted October 2, 2018 40 minutes ago, Yetti said: so if it had started what would have happened? Empty cockpit, no wheel chocks, and assume the parking brake is off, from where he stood, he had no chance... Fundamental question is: is there any difference between propping with the intent to start the engine vs propping with the intent to "lube" the engine? I was taught, to give due respect to the prop, there are no differences between these two... Quote Link to comment Share on other sites More sharing options...
nels Posted October 2, 2018 Report Share Posted October 2, 2018 13 minutes ago, Yetti said: so if it had started what would have happened? It would get plenty of oil at start up. Rotating one revolution isn’t a bad idea if the plane is put up for some time. I agree, not sure if the benefit out weighs the possible live mag. I can also see how a mechanical problem might show its face while flipping the prop through. Quote Link to comment Share on other sites More sharing options...
Stephen Watkins Posted October 2, 2018 Report Share Posted October 2, 2018 Pulling a prop through before starting is an OWT carryover from the old "round engine" days. In radial engines, under certain conditions, oil can pool in the bottom cylinders. Oil is not compressable, so if the engine is cranked in that situation, major damage would/could occur. To check for this, before starting, the prop is pulled through. If there is oil in the cylinder, it will 'lock' and the prop cannot be pulled through. If that happens, they pull a spark plug, drain the oil, clean the plug, and then start. See the link below: https://aviation.stackexchange.com/questions/29561/why-do-ground-crews-rotate-a-radial-engines-propeller-before-a-motor-cartridge On modern 'boxster' engines, I would not recommend this. You want to minimize any movement of the internal components when oil pressure is at zero. 2 Quote Link to comment Share on other sites More sharing options...
Bartman Posted October 2, 2018 Report Share Posted October 2, 2018 One more example why the prop should be treated like a lethal weapon 1 Quote Link to comment Share on other sites More sharing options...
Bravoman Posted October 2, 2018 Report Share Posted October 2, 2018 To me a prop is like a loaded gun pointed in my direction. I try to monkey with it as little as possible. 1 Quote Link to comment Share on other sites More sharing options...
orionflt Posted October 2, 2018 Report Share Posted October 2, 2018 1 hour ago, nels said: Turning the engine over just one revolution would put the suspended oil from the bottom of the cam lobe to the top of the cam where it is free to run back over the cam lobes while the engine is cool. that's assuming the engine is run regularly 1 Quote Link to comment Share on other sites More sharing options...
aviatoreb Posted October 2, 2018 Report Share Posted October 2, 2018 It’s a shame these engines don’t have some simply oil spritzer device already built into it whereby a little bit of oil could be drawn up from the case and spritz over the top to drip back down slowlybon it’s own. Maybe by pressing a button (like the manual rubber prime button on my gas powered tug) or even electronically controlled so it can be done by timer so that it can be timed to keep the engine well oiled during bouts of inactivity. Quote Link to comment Share on other sites More sharing options...
Marauder Posted October 2, 2018 Report Share Posted October 2, 2018 One more example why the prop should be treated like a lethal weapon I'll tell you another lethal weapon. The nose wheel. Anyone ever tried pulling a Mooney out of a hangar with the tow bar and on a sheet of ice in front of the hangar? I could have sung the Nutcracker in alto. 3 4 Quote Link to comment Share on other sites More sharing options...
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