Sunday, June 3, 2012

Knights of the Round Engine

Those rotary engines. . . the Le Rhones, the Monos, and the Clergets! They made a sort of crackling hiss, and always the same smell of castor oil spraying backwards The 0il in a fine mist over your leather helmet and your coat. They were delightful to fly, the controls so light, the engines so smooth running. Up among the sunlit cumulus under the blue sky I could loop and rolls and spin my Camel with the pressure of two fingers on the stick besides the button which I used as little as possible. Looping, turn off the petrol by the big plug cock upon the panel just before the bottom of the dive, ease the stick gently back and over you go. The engine dies at the top of the loop; ease the stick fully back and turn the petrol on again so that the engine comes to life five or six seconds later.
- Neville Shute

What always strikes me when I get together with a certain bunch of friends is as all the conversations going on all at once about such varied subjects - Heinlein, Cordwainer Smith, reloading, airplanes, caffeinated beverages, trains, planes and automobiles and scotch eggs.

One discussion was on starting steam engines on trains, and that launched a conversation on  starting round engines on airplanes as they are, shall we say, a bit temperamental.

You hardly see them any more, but those of us who flew them continue to share the wisdom.

The ancients wrote that the great things to be seen are sun, stars, water and clouds. I think they forgot the round engine.

I have a fair amount of experience flying jets and as much fun as I had, I do have to agree - there is absolutely no mystery to a jet engine.  The air travels through it in a straight line and doesn't pick up any of the pungent fragrance of engine oil, hydraulic fluid or pilot sweat.

The rules for the operation of a jet are basic.  When I first had some beginning airmen to teach there was this preprinted poster with the "four forces of flight". Lift. Weight. Thrust. Drag. Each were represented by a drawing of a man.  I, of course, drew a dress on Mr. Drag, which now would just get me sent to the corner for "sensitivity training".  But it wasn't all that much harder to teach airmen gas turbine engine technology.  The basics of how the jet engine works can be found in the story line of any X rated film.

Teaching someone to start one  is even easier.  Anyone can start a jet engine. You just need to move a switch from "OFF" to "START" and them remember to move it back to "ON" after a while. Sometimes you don't even have to remember to move it back to "On" as the switch is spring loaded. To start a jet engine you need a couple of fingers.  To start a round engine you need two hands that can move like a hummingbird on crack. The right hand for the primer, energize and engage switches, the left hand being busy with the throttle, magneto then back to the throttle to control the starting RPM and then for the mixture and. . .

Even being ambidextrous and nimble isn't enough start a round engine, you seduce it into motion, which requires skill, finesse, patience, a gentle touch and a fair bit if style. Failing that there is curse words. If that fails there is meditation and celibacy. If the mission is critical you don't let the new guy start the engine. On some planes the pilot isn't even allowed to do it.

Just as you don't want to start a conversation with your wife that starts with "what the hell!" or contains the words 'breast enlargement', 'Oprah',or 'your mother', you do NOT want to start the checklist with the preamble of "this baby always fires right up!".  You've jinxed yourself right there.

You've just got too much working against you.  For starters, there is no computer controlling the fuel/air mixture.  If the mixture is too rich you'll end up with parts of the engine that look like wet charcoal briquettes and then it's NEVER going to start.  If it's too lean it won't start.  The mixture is like being married, giving you new ways every day you can be wrong.

Jet engines start by whining for a while, then give a delicate girly little "poof"and start whining a wee bit louder. Round engines give a satisfying rattle-rattle, click-click, BANG, more rattles, another BANG, a big manly BELCH, followed by the  explosive resonance of of a mechanical FART, more clicks, a bunch of smoke and finally, the serious perfection of low pitched roar.  It's the sound that machines should make.

As many have said, starting a jet engine is about as 'exciting as turning on your ceiling fan'.  Click.  Done. The passengers look bored.  When you have started his round engine successfully your Crew Chief looks at you as if he'd like to marry you, or at least let you borrow his car. If it's a particular cantankerous bird sometimes the passengers applaud.  Successfully start your jet engine and your copilot yawns.

Jet engines don't break or catch fire often enough, which leads to complacency and inattention.  Think about it, the round engine could blow an oil seal ring, burst into flame or sputter like a Democrat at a debate, then suddenly quit, at any given moment. Even a perfectly operational round engine at speed looks as if it's going to blow any second now. This helps keeps the crew concentrated on the job at all times.  You never saw round engine pilots playing on their computer or falling asleep in the cockpit. No sir.

Jet engines don't' have enough control levers or gauges to keep a a pilot busy. There's nothing to fiddle with during really long flights other than the FMS or your lunch. 

Round engines smell like  your favorite shop, or being in your favorite shop after barbecuing pork.  Jet engines smell like a dirty flashlight. At the end of the day in a jet you smell pretty much like you did when you started. When you go home from flying a round engine, you smell like Kuwait.

But if you are so lucky to have flown one, you will never forget.  Those mornings getting to the flight line, the normal edge of nervousness that precedes any mission humming from within you.  The airplane looms into view, that big round engine looking bigger than when you left it, as if it grew in the night.

The cockpit is as dark as space, as if marooned somewhere in the cosmos, waiting to swallow me up if I screw this up. My uniform shirt is stiff, my hands are ready, time to show this airplane who the boss is, or remain forever still.  We wait for orders, we wait for light, a hesitation in cooling space across which blew the dense oily smell of a radial engine, laying like cold smoke against my tongue, so thick I can taste it.

How well I remembers those moments, the small trickling of fear, not a fear that you can't conquer a simple engine, but the feeling we all have when entering a realm that man wasn't intended for.  I think about silent failures, of fire, of flame, the feeling of immortality that is the luxury of youth long having left as one takes on responsibilities not meant for children.

I'll lay my wits against a round engine's smoking passivity and if the stars align right we'll be on our way.  We'll be up where the air is fierce and cold, surrounded by all that is familiar, the dials, gauges, switches, each with a mark of human hands and sweat on them. Shadows bow before a waving sun, the chill in the air an intractable summons of fall, cast upon summer skies.  From up ahead, another plane in our group, the spurt of smoke from her, the only sign of movement.

Constantly keeping the instrument in my scan, we're moving forward only by blood and sweat, history and  instinct, compassing forever between safety and a horizon unknown. Clouds build in the distance, lightning flashes off to our right, the sky full of promise and danger, vast bodies of water into which we could disappear forever, tall mountains of ice and rock and fluid need. We are aware of little of it and all of it as we wonder just how many hours ahead it will be before gravity and sleep and a cold beer are in our view.

We must have patience, and we do, for we fly round engines.

 - Brigid


  1. Brigid,
    Thanks for the memory jolt. Took me back to Edwards AFB in the early 70's. Fresh off the farm, working on the mighty C-131E. Pulling the props thru on preflight; counting the rotations on start. Then the best sound in the world-ignition. You describe starting one the best I've heard. Burping, belching & farting. And that was on a good day!

  2. While I have a handful of hours flying round engines. I've spent more time riding them to altitude prior to jumping out. Beech 18s used to be a mainstay, along with a few DC-3s and Lodestars.

    I love the rumble of the seven and nine cylinder engines, but I also have a soft spot for the pocketa-pocketa of the five cylinder radials on some of the early small biplanes.

  3. A Wise Man once told me "Real airplanes have ROUND engines".
    He mentioned something about "And two wings", but the "round engines" part always sticks with me.

  4. Last Gary airshow I was at they had those yak 52's, I think they were, with that big radial 9. Those things were helicopters, I swear, they spent more time pointing straight up or down than anything else.

  5. I agree with Tom.
    Takes me back to Yuma 1974. Setting in the left seat of a DC-3. My dad in the right seat walking me through the start, taxi, take off, slow flight stalls, (we dont talk about the spin entry) and the landing. Later that day 10,500 west bound, now in the right seat, pop in the left,
    32 guys on board. I am the only one awake.
    Not bad for a 19 year kid.
    Can still hear the inverters and smell the soul of the plane.



  6. "this baby always fires right up!"


    When I was in SC last month, a small mono flew over the conference center during our lunch break. Those radials certainly do have a distinct sound.

  7. Hubby had the privilege of being behind Fifi on startup once when it visited. His clothes were covered in oil, but it is still way safer than being in front of all those flailing blades.

    It is amazing to watch the folks at Pioneer Airport hand prop some of the older airplanes. And yes, they do still have all their fingers. Since I'm not an A&P, they handed me the polish and told me to make an aluminum skinned airplane shine. I eventually found the little pond nearby with the hungry bluegills instead.

    Have you ever been to EAA? The summer fly-in has lots of airplanes with round engines. (shameless plug for local tourism there, sorry)

  8. Another wise man told me if a round engine ain't leaking its out of oil.

  9. I've always thought it odd, that on single engine IC planes, the exhaust is piped directly into the pilot's face.

    Or so it seems to me.

  10. I started flying late in a country airport out in the boonies. The airport housed a number of old aircraft owned by older pilots. Down the row of t-hangers resided a Waco and two Stearman biplanes. I learned early how to swing a prop and more importantly how to step away when I did.

    I don't remember hearing anyone call the starting sounds a "mechanical FART."

    It fits, though. Ah, good memories.

  11. Doing penance in a staff job back when there was still a requirement to fly monthly hours for pay, I was forced into flogging a T-29 (Convair 220/320/440 class).

    I learned that fighter pilots don't meld with "crew coordination" and that radial engines have more than a handful of operating limitations, unlike jets. After my first check ride, the flight mech told me never to again touch an engine control. Simply tell him what I wanted regarding power in simply fighter driver words like "more" or "less" or "go up now".

    I made myself very scarce when flight scheduling would call my office. Twenty months of my life in which I didn't want to fly.

  12. I SO want me something that has one (or more) of those. Sigh...

  13. Guy at the local muni has a Stearman. I like to walk around it in the hanger just inhaling deeply. Dope, fuel, oil, sweat, and old leather.
    Jets can't match that.

  14. ...and for crying out loud, don't forget to crank it through by hand a few times to clear the oil out of the bottom jugs (or else).

  15. My one and only experience actually flying a round engine was a nifty little Ryan PT-22 with a five cylinder radial. I wasn't allowed to start it or fly it alone, but it left an impression for sure. I have had the privilege of sitting in the cockpit of a P-47. What I wouldn't give to fly one of those.

  16. Don't forget the man on the ramp with the fire bottle.


I started this blog so the child I gave up for adoption could get to know me, and in turn, her children, as well as share stories for a family that lives too far away. So please keep it friendly and kid safe. Posts that are only a link or include an ad for an unknown business automatically to to SPAM..