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Hand Prop Start When I started crop dusting in 1975, the guy that I first went to work for had 4 open- cockpit Stearman 450 HP (R-985) planes to use. When we showed up at 4:30 am, the first thing the chemical loader and I had to do was start 2 of those junk airplanes. Since I was new (an apprentice duster pilot) and an Air Force trained pilot, not a start-out-from-the- ground-up pilot, I had to do the grunt work and the loader would operated the throttle. Those worn out 985's would let the prop make 2 or 3 revolutions or more on each throw. The secret was to move the prop until you imagined that you felt some compression then yell at the loader to turn the mags on (if he bothered to turn them off in the first place). With a little practice and a lot of fear it was easy to cock your right leg, swing it back and around to get your momentum going out of the way of the prop and the plane if it jumped and at the same time throw the prop thru the mag impulse. That got the oil to splash on the various things that needed oil and get a little sweat moving under the hat. That was the first of about 10 minutes of work before you would hear the first soft fart of a cylinder firing. At that point conversation was limited to four letter words. Believe me nothing would make you madder than to finally get the engine to fire and start a slow chug as the prop made a couple revolutions on its own power then have the loader screw things up by not making the proper adjustments on the throttle and watch the fires go out and the prop stop. And that was the first airplane, one more to go. I was the happiest of duster pilots when he finally bought an Ag-Cat (that used a start cart), then sold that and bought a couple Cessna Ag-Trucks. Propping a round engine isn't bad since the props on those engines have a lot of weight and momentum when they swing. 3 bladed props on a -520 or -540 opposed engine are tough to get your hands on (angle is awkward, blades are relatively sharp) and move thru only the first or second cylinder when you throw the prop. If the engine is warm, or you get it to start then let it die, getting the engine to fire can take a long time and a lot of work. Thank god for turbines. From one who has done it many, many times. Gene Hamner Barely a teenager, I first soloed a J-3 Cub, upon which I learned to hand prop in relative safety. I took my private pilot's checkride in a Piper Colt with a mighty 108 hp engine and a starter, along with a radio. Now there is progress! In college, one of my part-time jobs was working as a line boy at the Ohio Sate U. airport. I propped Stearmans, Twin Beeches, Cessna 195s as well as all the smaller types. Those mentioned present a particularly tricky situation, as their props are huge, turn hard, and the bottom of the prop arc comes to within inches of your legs because they are taidraggers, tail low/nose high. You can't stay at arm's length when you prop one of those suckers. Of course, one secret of long life in that business was to cozy right up to the prop rather than stand back, so that if you lost your footing or balance, you would tend to fall away from the prop rather than back into it. But with the big-propped taildraggers you were still bent forward in order to keep your legs connected to your knees, so it was awkward and difficult. My dumbest stunt of the times was doing all this on ice one cold, dark winter night. Now there is dedication to the job, way beyond the call of duty! Or just simply stupid. I was still bulletproof then. Which attitude served me well a few years hence in a far away tropical paradise. Fortunately, I didn't have to prop any planes there. Brakes, Contact, ------------------------------------------------------------- We still have all the A&P students hand prop the A-65 Continentals (1st engine they tear down reassemble and run) in Powerplant. They also do an IO-540 or O-540, and an R-755 Jacobs in the 1st semester. Kevin Kammer (the instructor) believes firmly in discovery and reinforcing lessons learned from not reading all the job sheets (within safety limits). This leads to great amusement (and reinforced experience based learning) when they get to prime the oil systems on the IO-540. If, as many do, they fail to prime the oil galleries, they often spend considerable effort hand propping the engine to get the oil pressure up. The ones that still don't read the job sheet after we have them squirt oil into the pump and galleries, then spend considerable effort to finally get an indication on the oil pressure gauge. The few that finally give up and ask how we would do it are referred back to the job sheet in the hopes that they will finally notice that it says to use the starter once the pump and galleries are primed. Nobody makes the same mistake on the Jacobs. In the General course, they get to hand prop the Aeronca 7AC, with a reminder of the guy that failed to catch his as it took off without anyone aboard. We now use the starter on the Cherokee and Twin Bonanza, Since Al White's demo of hand propping the Cherokee turned into a lucky (therefore funny) adventure in outrunning the airplane. He couldn't stop it, though, before it hit a chain link fence and turned the spinner into a corkscrew. (He'll probably never forget to check the tie down rope condition again.) The one that takes the cake, though was a fellow down in Australia, that let his plane get away after hand propping and slicing and dicing something like five of a flight school's aircraft. He's apparently not claiming to be an "Ace" so maybe it was less than 5. Will see if I can scare up some of the pictures. Jim Young
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