The Dangers of Props (Could not think of a better Subject title)

[Mike Griffin]

On March 20th of this year, I had a pretty bad heart attack.  Actually, all heart attacks are bad.  As a result, I was put on several medications one of which is called Brilinta which is a powerful and very expensive blood thinner.

Because of this, I bleed profusely from even a minor cut or scrape and I will not even get into how badly your bruise from just bumping in to something.

Over on facebook in one of the Control line forums, somebody started a thread about using your finger to hand start and engine versus using an electric starter. There were some pretty silly statements made such as implying your were “not a man” if you used alternative methods to start and engine.  If found that statement to be particularly laughable. 
One person made a statement that he thought most injuries to the fingers or hand were caused by trying to take the glow starter off or by trying to adjust the front needle valve, which I think has a lot of validity as well.  That is how I seriously injured myself several years ago.

So the debate continued and as with any so called discussion, there were valid points made as well as some pretty dumb ones.
This got me to thinking about something and thought I would throw it out for discussion keeping mind that I have stated the dangers of bad cuts due to blood thinners.

I have used in the past either a heavy leather glove or a chicken stick to flip a prop.  I have also used an electric starter, which may possibly do some damage to a glow engine if you use it improperly.  A remote or back mounted needle valve makes sense to lessen the chance of getting your hand in the prop but not all glow engines have this feature.

Now for my question, after all of that:  Has anyone ever thought of or come up with some kind of instrument that you could adjust the front mounted needle valve that would not require you to get your hand so close to the prop? I kind of envision a tool that would clamp on the wheel at the end of the needle that would have some sort of release mechanism once you have the engine running where you want it.  I realize that all needles are not shaped the same so the tool would have to be universal.  Maybe someone else has come up with a solution that I am unaware of and please share if you have.

Mike

[Gerald Arana]

Mike,

I use a piece of thick (3/16" or so) wall hose about 3-4" long over my finger when propping an engine.

And YES! it has several cuts in it that my finger didn't get! 

Good luck, Jerry

PS: I put my hand under the engine to remove the glo starter and remover what looked like hamburger........DUH!

[Dan McEntee]

   You can install a rear mounted needle valve on just about any model engine that does not have it already. I installed them on all of the engines Sean used when he was younger just to help him feel more confident about adjusting a needle and got more experience.  Starting procedure and the tank location and position when it gets to the point where it runs out of fuel takes a little practice and set up. Combat guys have been doing this for years. Speed and some racing guys do this also. I have seen the late, great Glenn Lee use a long, tube type "wrench" to adjust the needle on some of his bigger speed models. This is nothing new. OS and McCoy have the twanger spring type needles on their engines so you could pull it back at angle. Wen-Mac engines had this feature also, and so did many spark ignition engines. For some R/C engines, there are remote needle valves control by the transmitter that fine tune the setting once under way. People have been hand propping engines on full size aircraft since the Wrights quit the bicycle business. You just have to know what you are doing, have a set procedure in mind, do all adjustments from behind the prop. do things the same way EVERY TIME, and make sure that anyone helping you knows what to do and most importantly, what NOT to do.  It's all up to the operator. You either know what you are doing and do it correctly, or simply do NOT do it. We are talking about a running engine here, where the risk is higher. If you stick your hand into a running prop, that is all 100% on YOU! That is 100% preventable. You have to respect the prop, or at least be very afraid of it!!  Starting is easy. Use your fingers or a starter, but a starter can do a lot of damage to an engine. I have seen it as long as I have been doing this stuff. If the engine doesn't start within 1 second of applying the starter button, something is not right. Follow the same procedure you would for hand starting and it most likely will. Guys get lazy once they get used to the idea of a starter. Again, this is noit anything new!
  Type at you later,
  Dan McEntee

[Brett Buck]

Now for my question, after all of that:  Has anyone ever thought of or come up with some kind of instrument that you could adjust the front mounted needle valve that would not require you to get your hand so close to the prop? I kind of envision a tool that would clamp on the wheel at the end of the needle that would have some sort of release mechanism once you have the engine running where you want it.  I realize that all needles are not shaped the same so the tool would have to be universal.  Maybe someone else has come up with a solution that I am unaware of and please share if you have.

Mike

   OS has been putting remote/rear-mount needles on engines for 20+ years. Too bad the first thing everyone seems to do it take them off, throw them away, and put the needle back next to the prop! I have used them, they work fine in most respects. The supposed "lag" in the needle response from the extra 2" of fuel line is about 3 microseconds (how long it takes a pressure wave to get from the valve seat to the nozzle at 5000ish feet/second). The one issue I have had with it is on profiles, putting the fuel across the top of the engine allows the fuel from your choking to run back into the tank between "pulls" so you can get it to pop but not keep running. That is solved by not waiting, pull it through and flip immediately.

    Otherwise, I would agree that most of the really bad incidents of recent years have not been at the point of starting it, but other things. Starting modern engines using the back-bump method is so darned easy that no one has their finger anywhere near the prop when it starts. Reaching across the prop to remove the battery, and, strangely, dragging various bits of your hand and arm moving your tools seems to be the trouble spot.

   Part of the problem of changing procedures is that once you have a procedure and have done it 10,000 times, you create extreme risk just from changing it. Almost all of the really bad recent accidents were the result of having to do something unexpected or out-of-order. If I tried to use an electric starter, for instance, I go from a very successful and practiced routine that has been 100% success rate over about 50 years, to grappling with a whole bunch of stuff I have never done, with new risks. Give than your finger is nowhere near the prop when the engine starts, I choose to continue as I have. Same with adjusting the engine while standing behind it - it's a new, awkward angle that creates new risks.

   There are other dangers that no one seems to want to talk about with modern engines. They start so easily, they can start with no battery on them, at the instant you attach the battery, or a number of unexpected points. So you want to be sure to have the airplane under control and anticipate that it can start any time there is fuel around it. Most people know to deal with it after a few "surprises". The most risky thing I see people routinely do is to choke the airplane, think it is ready to go, then reach through the prop to attach the battery. While you are doing that, for certain, *hold the prop with your other hand* near BDC, because the instant you touch the battery to it is far and away the most likely point for it to start unexpectedly.

    There's a lot to this, and if you are using vintage engines, you are in more risk because you frequently do have to flip them forward through compression. That's something you more-or-less never do with modern engines at least with the battery on.

      Brett

[John Rist]

I know this comment makes me smart %$%$ but to cure the problem I have gone all electric.         

[Dave Rigotti]

Problem solved. NO needle valve at all! If you can push a button you're motor will run. To adjust the RPM do it on the ground with a programmer that has no danger of slicing your finger(s).  Did I mention repeatable too?  Oh well.....

I know this comment makes me smart %$%$ but to cure the problem I have gone all electric.         

[Brett Buck]

Problem solved. NO needle valve at all! If you can push a button you're motor will run. To adjust the RPM do it on the ground with a programmer that has no danger of slicing your finger(s).  Did I mention repeatable too?  Oh well.....

  I just skipped the obvious!  I knew you guys had my back on this.

   I will make sure Larry is aware of this so you can be considered for the list. Credible first effort, keep up the good work.

     Brett

[john e. holliday]

Electrics to me are the most dangerous if you forget your routine.  Electric keeps on trying to run even when your gets in the prop.  I have one plane that I will not reach for the needle as there is no room when engine is running.  I stop it and set the needle either leaner or richer and then start again.  On my twin I start each engine and set it using the tach.  Once each engine has been started, set and shut down I top off the fuel tanks.  Then with glo clip comng over the top of the wing to the engine(inboard engine first) I start it  and then move to outboard.  But, I use electric starter even though engines will usually start first flip.  It takes practice, patience(which I lack at times) and staying alert.  I still have scar from the time I was going to put up maiden flight on the B-25.  Sure glad I had Dave Trible and some quad fliyers there that day.

[Mike Griffin]

I realize the differences of using electric systems vs glow.  This seems to always come up when a discussion on glow engines and safety comes up and the debate starts. I was hoping it would not go this way but it always does.  My question was to safety using glow engines, not electric systems. There are advantages and disadvantages to both.  I have 3 electrics that I fly as well and one is an Igor Burger design. Thanks for the help guys. 

Mike

[Colin McRae]

I have seen people cut fingers on electric CL. But as others have said mainly due to pilot error and being complacent.

I always use a leather glove to start my glow engines.

Concerning remote NVA's, I also do run a few OS LA (and FP) engines with remote NVA's on profile models. The engines run great, but I have switched a couple to front NVA primarily for one reason. The engine runs rock solid until just at the end of the fuel run, tank almost empty. Since the remote NVA tubing goes up and down into the spray bar, the engine sputters for maybe 2-3 laps due to bubbles in the lines until all the fuel is gone. Just not what I prefer. This does not happen with the front NVA. When the fuel is done, the engine just quits. (Just my personal preference.)

[Motorman]

I've been hand propping rat race/combat engines for decades and I'm very good at it even bare handed but I'm never putting my hand on a prop again. I can tell you with all certainty anything you wear on your hand for protection is a false sense of security. Leather gloves, rubber hose ect. will get chopped in half just like butter if you stick it in a running prop. After years of wearing out the right hand fingers on many leather gloves I've gone to the chicken stick and I'm never going back. You can get just as adept at using the stick as you can with your hand. No need to put your fingers in the salad shooter. Wish I had one when I was young.

MM

[Dave Hull]

Maybe to expand on what Dan was perhaps alluding to...?

"OS and McCoy have the twanger spring type needles on their engines so you could pull it back at angle."

The ones I recall from long ago were aftermarket universal needles by (Austin-craft???) The were long and had a tightly wound spring soldered in the middle. You put a brass strap clamp under the forward engine mounting bolt to hold the clamp. Then the needle with knob was pointing pretty much straight back. Fine for any profile. Your fingers were out of the way of the prop and they turned easy enough for the whole deal to work properly.

Dave

[Jim Kraft]

   Blood thinners are bad news. I had a stint put in my aorta a couple of years ago, and they put me on Brilinta. After a year they switched me to Xarelto.

I began feeling bad but could not figure out what was wrong. It showed up in the bathroom shortly there after. My hemoglobin was down from 15 to 7. A 90 mile trip by ambulance to a hospital that would take me. The doctor scoped my digestive tract and cauterized my bleeding ulcer. That was last February. They gave me two units of blood to get me started back to recovery. It took about 60 days to get back to 14. No more blood thinners for me except for 81 mlg asprin a day. So far so good. I had to have another scope done to make sure I was healed after 90 days. All healed up.

Many of the old ignition engines had long needles with springs to be mounted way back from the prop. You could still get pretty close because the timer arm was also close to the prop. But at least the needle was out of the way.

By the way, I never had much trouble with Brilinta. It was the Xarelto that did me in. Bad stuff. Even on a low dose. At least for me.

[Dan McEntee]

Problem solved. NO needle valve at all! If you can push a button you're motor will run. To adjust the RPM do it on the ground with a programmer that has no danger of slicing your finger(s).  Did I mention repeatable too?  Oh well.....

   I think that if you would search the forum a bit, and certainly the internet, you will find instances of electric models getting away from guys on the work bench while testing the systems with the prop on the motor! You think things are safe, then push the button, and the first thing you instinctively do is put your hands out toe stop the electric monster! U know it's happened before, even going back to my electric sailplane days. Those things had no throttle or soft start. If it came alive, it was at full tilt boogie right away! I know it happened to sailplane guys. The early F3E models were down right scary. Models powerful enough to climb out of sight in less than a minute, but you had to demonstrate motor on and motor off to the timers. When they did that the holder usually had a hold of the fuselage with both hands, and a stable, legs wide apart stance to withstand the blast. Today's electric models aren't like the Stanzel Electromic toys!!
   Type at you later,
  Dan McEntee

[M Spencer]

Huming and Hawing .
as to wether to contribute .
As a DANG DOG next door needs ufanasing,  I JUST TROD on the Soldering Iron . As its bl**dy barking had me TURN & move my foot without LOOKING .

Which is HOW most Prop Strikes Ive Observed ( and Suffered ) HAVE OCCURED . A &^#@ cetra  UNHEEDING that props can be a bit annoying , attempts to Catch Your Attention .

OR there MOVEMENT close at hand , Has you swing . Often on your knees , as theyre to your Left . You right arm is out for balance as you swing to see wot the F%@* is THERE .

Bother Ouch Mutter  etc .

Not a problem usually at comp.s bar maybe a over keen photographer or Video Director . They usually use a fancy lens and get well back .
But at the sports field , or even  at home . WHAT , you start your Engines at HOME .  Some turkey ' outvibeing you , like silly mongrels tend to ,
being cunning sods and neurotic . They probably PLAN it . Or their general befuddled mind ANTICIPATES ' trouble . Opening the door to it .
OBSERVE most turkeys get hysterical & blather CO DRIVING creating mayhem .


So If there one around , carry a few rocks in your pocket . If they come closer than 50 yards , LETTUM HAVIT . 

[M Spencer]

Same Phycology . OH he loves his motorcycle more than poor little helpless distraught me ,  Sub Concious ? maybe I should leave a spelling tape on while I sleep . If the F ng dog hasnt got the boiler at full steam till sunrise . AS USUAL .

[Ara Dedekian]

      I'm lucky enough to be able to make my own venturies but the Bic pen is my go-to system for keeping my fingers intact. It works really well.


      Ara

[John Park]

The British firm FROG used a simple answer to the needle-valve problem on their FROG 500 glow motor back in the 1950s.  Google in 'FROG 500 engine' and you'll see that they just extended the flexible part of the needle with a piece of piano wire and added a clip to hold it back, well clear of the prop.  It shouldn't be too difficult to extend a modern flexible needle in the same way.  On our small British diesels, whose needles are plain stiff piano wire bent to an L-shape at the end, we sometimes used (and still use) a simple tool consisting of a piece of dowel long enough to clear the prop. arc, with a slot to engage with the L-shape.  Something similar, more robust and fitted with a T-bar to turn it, is a good idea for adjusting the compression screw of a diesel.  I must make one for myself - only last week, I got a lacerated knuckle while adjusting a little Mills .75 in a C/L trainer I'd made for a friend - good job it wasn't one of my big PAWs!

John

[John Park]

I've just realised - K&B used the same NV arrangement on the Torpedo as early as 1947.  The FROG 500 was an almost exact copy of the Torp!

[Steve Dwyer]

Mike,

It certainly would be an improvement in safety development if someone came up with a way to adjust a front mounted NVA without the risk of nearing the prop. Admittedly, I personally prefer the front mounted valve arrangement to the OS LA back plate configuration primarily because of the control lag, added tubing and especially the plastic backplate but more so because it's the old standard of the 50s we grew up with.

Unfortunately we cannot get away from the buzz saw but we can maintain more respect and less complacency when starting a gas engine. I recently learned I must be more careful. Fortunately I do not have blood thinning issue you have, if I did a recent (embarrassing) experience would probably been a more serious. In early May, fresh out in the season and alone at the field I was careless in connecting the stooge. I had gotten use to connecting the tail skid from the front of the plane. The short of it was I discovered what an APC 11x4 on a 40 size engine can do to soft tissue. 19 stitches later I realized I have to be more careful. It took two weeks to fully heal and before I returned to the field.

Now the tail skid is connected by looking from the rear of the plane giving it a tug to be sure it's attached. Once the engine is started I will no longer have my face directly over the circumference of the prop while reaching behind to adjust the valve. I will only make any adjustments from the rear of the prop by walking behind the plane. My fingers are still close to the buzz saw but I feel I have a much better vantage point to safely make adjustments. Stay safe!

Steve

[Mike Griffin]

      I'm lucky enough to be able to make my own venturies but the Bic pen is my go-to system for keeping my fingers intact. It works really well.


      Ara

Ara,

The BIC pen tool is really creative and I am going to give that a try.  Thanks so much for posting that picture.  I will also utilize the dowel pin with the slot in it as well since I do have some needles shaped like that as well.  I appreciate the reply John.

Mike

Mike

[Mike Griffin]

Mike,

It certainly would be an improvement in safety development if someone came up with a way to adjust a front mounted NVA without the risk of nearing the prop. Admittedly, I personally prefer the front mounted valve arrangement to the OS LA back plate configuration primarily because of the control lag, added tubing and especially the plastic backplate but more so because it's the old standard of the 50s we grew up with.

Unfortunately we cannot get away from the buzz saw but we can maintain more respect and less complacency when starting a gas engine. I recently learned I must be more careful. Fortunately I do not have blood thinning issue you have, if I did a recent (embarrassing) experience would probably been a more serious. In early May, fresh out in the season and alone at the field I was careless in connecting the stooge. I had gotten use to connecting the tail skid from the front of the plane. The short of it was I discovered what an APC 11x4 on a 40 size engine can do to soft tissue. 19 stitches later I realized I have to be more careful. It took two weeks to fully heal and before I returned to the field.

Now the tail skid is connected by looking from the rear of the plane giving it a tug to be sure it's attached. Once the engine is started I will no longer have my face directly over the circumference of the prop while reaching behind to adjust the valve. I will only make any adjustments from the rear of the prop by walking behind the plane. My fingers are still close to the buzz saw but I feel I have a much better vantage point to safely make adjustments. Stay safe!

Steve

A

Sorry this happened to you Steve.  Over the years, I have had two incidents of prop injuries and one nearly took my thumb off and it actually fractured the bone.  An APC prop spinning about 10,000 RPM is like a razor blade spinning at that speed.  At 75 years of age and not as coordinated as I use to be along with blood thinners, you can get in serious trouble quickly.  Thank you for your reply.

Mike

[Mike Griffin]

Huming and Hawing .
as to wether to contribute .
As a DANG DOG next door needs ufanasing,  I JUST TROD on the Soldering Iron . As its bl**dy barking had me TURN & move my foot without LOOKING .

Which is HOW most Prop Strikes Ive Observed ( and Suffered ) HAVE OCCURED . A &^#@ cetra  UNHEEDING that props can be a bit annoying , attempts to Catch Your Attention .

OR there MOVEMENT close at hand , Has you swing . Often on your knees , as theyre to your Left . You right arm is out for balance as you swing to see wot the F%@* is THERE .

Bother Ouch Mutter  etc .

Not a problem usually at comp.s bar maybe a over keen photographer or Video Director . They usually use a fancy lens and get well back .
But at the sports field , or even  at home . WHAT , you start your Engines at HOME .  Some turkey ' outvibeing you , like silly mongrels tend to ,
being cunning sods and neurotic . They probably PLAN it . Or their general befuddled mind ANTICIPATES ' trouble . Opening the door to it .
OBSERVE most turkeys get hysterical & blather CO DRIVING creating mayhem .


So If there one around , carry a few rocks in your pocket . If they come closer than 50 yards , LETTUM HAVIT . 

Mr. Air Ministry,

I always enjoy reading your posts, but I do not understand a darn thing you say.  I am sure it is helpful, but I need a translator.

Mike

[Mike Griffin]

   Blood thinners are bad news. I had a stint put in my aorta a couple of years ago, and they put me on Brilinta. After a year they switched me to Xarelto.

I began feeling bad but could not figure out what was wrong. It showed up in the bathroom shortly there after. My hemoglobin was down from 15 to 7. A 90 mile trip by ambulance to a hospital that would take me. The doctor scoped my digestive tract and cauterized my bleeding ulcer. That was last February. They gave me two units of blood to get me started back to recovery. It took about 60 days to get back to 14. No more blood thinners for me except for 81 mlg asprin a day. So far so good. I had to have another scope done to make sure I was healed after 90 days. All healed up.

Many of the old ignition engines had long needles with springs to be mounted way back from the prop. You could still get pretty close because the timer arm was also close to the prop. But at least the needle was out of the way.

By the way, I never had much trouble with Brilinta. It was the Xarelto that did me in. Bad stuff. Even on a low dose. At least for me.

Jim,

Thanks for this reply.  Folks who are not on a blood thinner do not realize that your life and the way you do things has to be altered and anything you do that may pose a threat to a serious cut, can be very dangerous.  Every time I pick up an Exacto, I have to concentrate hard on what I am about to do.  I had two stents put in and the "widow maker" artery was 99% blocked and the other one was 90% blocked.  Even the minor cuts like shaving with a blade become a real pain in the butt.  A deep cut can become very serious quickly.  I went in the donut hole with my insurance and the prescription is now $500.00 for a 90 day supply.  On a fixed income, this becomes a serious problem and that is not the only one that is expensive.  I am also on Entresto and it is almost as expensive. 

Screw the golden years.  LOL... thanks again Jim.

Mike

[Mike Griffin]

Mike,

I use a piece of thick (3/16" or so) wall hose about 3-4" long over my finger when propping an engine.

And YES! it has several cuts in it that my finger didn't get! 

Good luck, Jerry

PS: I put my hand under the engine to remove the glo starter and remover what looked like hamburger........DUH!

That would work.  I think I am going to just use a chicken stick from now on but the tubing over the fingers sounds like it would work as well.  Thanks for the reply.

Mike

[Mike Griffin]

Several comments on this have made reference to getting complacent and having accidents because of not paying attention and one reference was made about doing the routine for years and not having an incident.

I would like to cite and example of this that a CFI told me when I was taking flying lessons in a Cessna.  He had a friend who owned a twin engine plane and had thousands of hours in the cockpit and a sterling safety record.  One day he was coming in for a landing and when he heard the prop tips hitting the runway, he knew he had forgotten something.  He forgot to lower the gear and he belly landed the plane.

The point he was making was, it can happen to anyone no matter how long you have been doing something.

I was reminded of that story several years ago when I almost lost my thumb to an APC prop.

Mike

[Steve Helmick]

Jeez, the horror stories y'all tell! I haven't had any stents, but my older brother has two. I'm not sure if he takes any asprin or blood thinners, but I take 3 or 4  81mg asprin a day. I will bleed a bit more than I would like, but don't have the bad bruising problems that prescription blood thinners seem to give. I used to take one 325mg asprin a day, but that bothered my stomach, resulting in the change.

I like the idea of the BIC pen NV adjusting tool, but will have to ponder how to adapt it for use on a Randy Aero NV. Perhaps a plug in the end with a slot across? Probably would want a screwdriver type handle. Maybe would just start with a length of Delrin rod?

I don't think a metal tool is a good idea, but if one can arrange a socket head or hex head on the end of the NV, then a ball driver or nut driver could work. I'd be very nervous about putting something metal near the propeller, though. In the long run, it appears to me that maybe that'd be creating a bigger safety problem. Having fumbled a glow ignitor into an APC prop only once, I was impressed with result, and changed my starting proceedure immediately. Have a plan, and do it the same way every time.    Steve

[M Spencer]

Its poceedures .

With a motorcycle , before they did their thinking for you ,

It was necesay to follow a drill . to even start the thing .
Storys of Velo's breaking ankles . I aways thought exaggerated - But they have a nast short kick start , so who knows .

A bit like the getting the ' bump ' from the engine , you know its ready to start . THEN , I will look up and around , to see we are ' clear ' .

You dont want someone sneaking up on you and going ' BOO ' I got you ' . Just as your reaching for the needle - as it were ( metaphorical ) .
IF theres NO ONE but your pit man within 50 yards , your unlikely to be distracted .

2 . On Your Knees . When Frozen or roasted , or when I havnt done my 12 kilometer jog that morning  let me see , was it 1981 , was it 2  miles .

Starting the plane on the ground , IF your Kneeling - your not at your most stable . As regards verticality . Standing straight up AT the planes not a good idea . Specially FACING it .
IF you slip , wobble , or the knee or ankle bitches - your pitched forward . And put a hand forward to stop you falling . So Swinging about , as the first move  , you can push youself clear .
Rather'n fall in / on / thru it .

SANDING the infernal contraption , on the ground ! , a ankle did the ' go to sleep ' trick , from sitting on it , as I rose agony death and suchlike . Wobble Step ( Numb Foot Ouch wobble No feeling .
So there - sanding On the Deck , Standing up to step forward over the plane , is a ' High Risk ' move .  Swing Stepp Clear , Go Around . WHICH is the best proceedure with NEEDLE valves .

SOME of the problem is if your not got your feet firmly under you . As it were . Firmly planted and ship shape . Aten - Shun .  ( is it ? )
When we were kids - everybody was used to discipline . and Jump when I say JUMP . Whereas all the degenerate youth slouch and mooch about . where were we . 

PROCEEDURE . Discipline .  With a REGULAR pit man - your familiar with each others moves . Like Football teams , Fitters mates , or a B 17 crew . So you can / do ANTICIPATE - understand
whats up . With a untried crew , half the time / attention , is seeing and checking  ' the moves ' . Untill you become familiar & know the knacks and ways of shuffling about . No Problems .

But if someone NEARBY ( checked it wasnt knear bee , probly is in some places ! SEE ! ) They can say JUMP , and you might bl**dy Do It . Right into the prop . So dont HAVE nearbys nearby .
If sombody waves a ubrella at you five foot off , youd think He's gunna clobber you with it , and Dodge . As it were . Metaphor .

DISTRACTIONS theyre called   =  Make sure theyve been got clear , or WAIT .

Essentially , your opperating an AEROPLANE . Even if its a little one . If you have a ' drill ' say . WWII Battle of Britain , The Fitter & Rigger were ' On Hand ' , So CALLS were for Prop Clear - Chocks etc .
There were Three Pairs of eyes . The ground crew were the Pilots Eyes , ' in the pit ' ( Rivetment And Getting Clear .

One is ' doing a job of work ' . Like on a Motorcycle - Clear the Mind ( & mouth ) of other intreasts . Primary attention on task at hand , SECONDARY attention ( the Darting Eyes ) checking periodically for intrushions ,
Intruders .
Who Dosnt cast their eyes about the circle , at the Handle , before signalling Release . Unfortunately , flying , casting your eyes about for intruders distracts enormously from the flight precision and timing .

When we were kids , there were Two , you knew , who were observant and intecepted hair brained pedestrians , like a shepherd with his crook . The others just Lounged About basically . The wernt observant of the field outside the circle particularly . Particly as it was the path to & from the beach , in summer . Naw , pram pushers mostly . Strangely the neigbourhood louts were tame in the vicinity , a polite mild intrest . Mannerly even.
Most Peculiar . Maybe they thought we'd gettem . with the prop . Or was it just weight of numbers .

So ,  Get Clear , get up , get around the Outside , Get Behind It . FOOTWEAR even , Flying Shoes ? loose ones let the knee wobble get underway . instability . A ' standard ' set of ' Flying shoes ' is one less variable .

But if your with someone unfamiliar - run through the steps , get him familiar with the HOLD of the plane & CHECK its firm . New Guys tend to look around as you move - see . as most people DONT usually have people MOVING AROUND close to them . IF you do - you tend to swing around to get a better view , automatically . If your not planted four square - you put a arm or elbow out for balance . If its not your day , the propellors
beaten you to it . You put your hand in its spot . F#*^ S@(#  .

 Get Clear . get around the Back .

NZ were R C nerds , with a strop over the rear fuse , pegged 6 inch into deep soil  . Not FIRM soil . Theyed STAND DIRECTLY IN FRONT , and do their Run Up / Full Throttle Checks . Were they aware they had no brains .
Had the all copied the president . Were R C Flyers crainially depletted internally , or was it a Cult . Mustve been some BL**DY reason . Or were they without reason . HABIT ??

So , be AWARE of what you ARE doing . But DRILL , and you follow a safe proceedure . It Not Normal the get chop chop . IF you are not analising what your doing , the MOVES . Maybe trying a few variations ,
you leave room for error ?
 Start Up is NOT a ' casual ' proceedure . M' Cycle theres Primary and ' other ' attention . Like relaxed . 6 tenths  of full alert . But the SECONDARY should be also allocated . OFF or  controlled . Otherwise secondary
considerations ( wots for tea , can take the front seat . And what your supposed to be looking at isnt immediate .

Drill . Discipline . Proceedure . 

TThen it wont backfire and break your ankle . Its not  mandatory for being a Velo Fellow .    As in - Put Aside , DELIBERATELY - Other Concerns . And See that NONE are about to intrude .
If its a casual pit man , be more attentive patient and check step each move . 1 clear 2 clear etc . To avoid ' surprises . Which we classify as distractions . Self evident . Want NONE . Mind on Job at Hand .

I guess old Diesel blokes being having NREEDED to ' BELT ' the Prop . Have gained the knack of fast finger . Agian . Practised - the belt it through & out , is ONE move . Or at least COMBINEd into one .
If Im on a OFF day , I cant start to get that for them , diesels . Race Ones . Nasty old ones . B*^ ETA's  light flywheel . Gotyta get it right to go . This Drivle is derived ,
The ' Bump Start ' Back flick  so it backfires forward and starts itself . Light Pre Determined - Fast . Prop Position - likely blade vertical when Fwd against compression .
Right Handed - The Swing - Down and OUT before its got to Ign.  The SHOULDER is Going Down , driving ! the Elbows Going Down , and Mainly Back At the same time , also - the Wrist is swinging right .
These combine for lightning speed as the forefinger  ( 2nd acly )  Swings across too . 
Youve gotta do all that , Reversed , with a %#* Racing Diesel .  PAW 19 , No Nitrate , piggy motor - chewed fingernails , blood blisters and cuts , Shredded from sliding - after a Combat Meet - in School days .
Im not entirely nostalic about MOST crappy diesels .
Its a knack ,
Also a skill .
Like a chuck glider launch - a TECHNIQUE . But it DOSNT STOP THERE . Ones Full / undistracted ATTENTION  . Start - Clear - remove yourself . Then ( With Jeff if inverted ) Step Around , Grasp Flying Machine -
Check CLEAR . Rote the B*$ Upright . Re Check - Eye Cotact, nod  ( seen adjacent area also . - He has it . NODS . - Release . Step Clear . Around the Back & Out .

Point Being . There IS a Lot Going On . One Step at a Time . * We ALL do it . But Not ALL the time . planes wobble  . Wrists pass prop tips reaching from forward . Bad Move . answers Obvious . But inherent laziness
means a stroll to round the backs ; a lot of trouble  ( subconcious ) Cop Out self Goes Direct . Maybe even shutting off visually AL but Needle . Oh Dear . like dreaming / cornering on a m Cycle  . First No No
A tightening bend . You HAVE to look WHERE you WANT to GO . Cause thats where your going . If you LOOK where you DONT want to go , The D#%^ motorcycle dosnt know that  , so itll go THERE . Every time a coconut .
Just imagine youve got the Squadron Leaders beady eye on you . Thatll do it .

You could say the prop strikes a secondary = result of Some Other incident.
Antique old shitters , got your full attention , to drive them . Modern lifes not the same ,
People are used to NOT being on edge & focused on physical exacting tasks .
When they refer to us as ' athelettes , I take it to be insincere flattery .
A Athelkette WILL have ' The Zone ' at his fingertips .
Getting all the garbage well out of the way , gets us a start at  ' focused ' . If were that & undistracted . WHY would you stuff up .  Physical or mental . BOTh need  appliction , to the ' task .
NOT someting otherwise at that time the alligators are most previlant ( metaphor agian  . Prop = alligator . Goodnight ! .

[GERALD WIMMER]

Hello

Some interesting comments and a good read here especially from Air Ministry (MS) .
A leather glove is so comfortable , flipping props, welding, using the chainsaw and gardening but my sons prefer a chicken stick (looks like a bicycle grip on a wooden dowel).
As the arthritis gets worse I grab the electric starter especially for those annoying Fora Diesel engines (no you don't bust them only a mid air would take them out, just back the compression right off and warm them up till they fire and often the warm running setting is very close).
Model airplane engines cause painful injuries but motorcycles and chainsaws are much worse and we tend to be more careful with those.

Regards Gerald

[Brett Buck]

I would strongly caution against any sort of long extension you hold to turn the needle. It might save you getting a cut (which is extremely rare with even minimal precaution) but creates a new failure, that is, your tool getting in the prop and breaking it, breaking the tool, and flinging shrapnel everywhere at high speeds. That is at least as dangerous, if not more so.

      Brett

[John Park]

I would strongly caution against any sort of long extension you hold to turn the needle. It might save you getting a cut (which is extremely rare with even minimal precaution) but creates a new failure, that is, your tool getting in the prop and breaking it, breaking the tool, and flinging shrapnel everywhere at high speeds. That is at least as dangerous, if not more so.

      Brett

In my 65-plus years of messing around with model aero engines, and associating with other like-minded people, I have never seen or heard tell of any 'failure' of the kind envisaged by Brett.  I have, however, seen and heard of. and sustained, plenty of cuts to the hand (not just the fingers) inflicted by a spinning prop.  I know it's not "the done thing" to disagree with Brett, but in this case I fear I must.

[M Spencer]

The ' popular ' Supre Tigre N V A . GLAND NUT .
Adjusting , You ' nip ' it down so the needles not hard to turn ,
Once your happy with the setting , you bring it down more .
Likely not so its unturnable - but a lot clser . alledgedly to
stop the needle end vibrateing ! As some people say of them ,

A Trick , if on muffler pressure , Blocking the muffler exit / exits
if its giotta warm up - Block on & on . Blip Blip . Soon as theres
HEAT in the Engine , it usually becomes unesesary . So As To
AVOID having to Fiddle with the little tight needle up forward ,
Sometimes at the muffler side . Which isnt the best  as the
natural reaction to heat is to gettem ( fingers ) away from it .
As theyre boxed in by the muffler and prop , it can be awkward .

WITH the plane firmly secured by a able pitman N N pliers ,
but as with the gadets , if its vibrateing about , its near impossable .

The Slotted thing inside the tube , trick is less awkward , but a bar
out the side at the hand end , gets a good visual referance .

n.b. some people are observed to use saftey glasses & ear muffs .
As long as theyre not fall offable creating their own hazard .

Father had a tube for round the back of the head taped to the arms .
At the bench , glasses up on forehead . Reach Turn . Wheres my B glasses .
Um , on your head .
Oh .
Notta bad idea tho - a few inches slack & you can have them on your chest ,
or wearem up on your forhead where you cant see them , when not in use .

A 3/8 dowel with a slot in the end & a bit of tube ( Alumn. / Plastic tube& soft
say white pine , the prop should win , if it were to go in it ) Needs a indicator line
at least , for referance . Red Line at the needle end ? Obviously the bit at the end
diameter to go over the adjuster , if the NVA is the wire - bent end . Whod of thought.
Everone actually / Much Better to have the adjustment OUTBOARD for accessability ..

[Douglas Bykoff]

Wouldn't it be simpler and safer to ask a friend for help?

Recently 2 of our people had heart surgery in less than 2 months.

Fortunately, everything went well and they are now back on with the assistance of their son and friends.

[Mike Griffin]

This thread has been very informative and although the opinions vary, the input from everyone has been interesting and civil.  One thing that I might add is that as you age, I will be 76 in December, your coordination and stability have a tendency to deteriorate. My hand/eye coordination is not what it used to be and I have fallen a few times just from stubbing my toe or stumbling.  Add to this medication that thins your blood and even a superficial cut will bleed profusely, plus the arthritis in your fingers and you can have the perfect storm. 

I want to thank everyone for the ideas they have presented so far and I will do what I feel is necessary to protect myself and apply risk management.

Mike

[Dave_Trible]

Another thing to watch for is struggling to get the battery off the engine once in a while and becoming preoccupied with that and getting careless around the prop-or having the battery bounce INTO the prop. I cringe when I see guys reach over the prop to do this.    I find I'm saying to myself "go slow and THINK about what you are doing" more often as I fire up for a flight.  Might start painting the word "THINK" on the nose behind the spinner.  When I believe I'm getting to a (more) dangerous age to deal with  props I'll charge up the electric starter.

Dave

[Brett Buck]

In my 65-plus years of messing around with model aero engines, and associating with other like-minded people, I have never seen or heard tell of any 'failure' of the kind envisaged by Brett.  I have, however, seen and heard of. and sustained, plenty of cuts to the hand (not just the fingers) inflicted by a spinning prop.  I know it's not "the done thing" to disagree with Brett, but in this case I fear I must.

     You don't see it because no one does it, for the reason I have suggested. The reason we do what we do is not carelessness, it is that after millions and millions of flights from people of all skill levels, it is probably the best way to do it.

    The best way to avoid this problem is to use modern engines or at least those that are easily started by back-bumping. This nearly eliminates the possibility of getting cut flipping the prop. Otherwise, use a very strict and practiced procedure that you don't deviate from for removing the battery, adjusting the needle, and removing the equipment from the area. The latter is where most of the recent really bad accidents have happened.

    And, for the record, I have seen people trying to be safe and putting things into the prop, trying to be "safe". It is usually OK, because the angle of the prop pushes it back rather than suck it in. And a fair number of people having prop blades knocked off and destroying the airplane and flinging parts around.

     As always, it is just advice, but after many thousands of flights and watching many more thousands, including some accidents, that's my best advice and waving sticks and spin-tites around fractions of an inch from a prop sinning at 10000 rpm makes me very nervous.

        Brett

[Arlan McKee]

Most people can't keep a flathead screwdriver in the slot.

[Steve Helmick]

Gerald Wimmer, would you PLEASE translate the quote below from Air Miniseries' (sic) last post? You seem to have a better chance than most! I'm wondering if he's suggesting actually blocking off the muffler exhaust outlet, or pinching off the pressure line. I've never thought of blocking off the muffler exhaust outlet as a way to heat up the engine quicker, but it is my #1 choice for shutting down an engine in a hurry if something goes wrong. Such as, shaft run, broken prop blades, starting during my usual choke-flip-flip-flip prior to signalling the judges...without the glow ignitor installed. Had that happen a couple of times. I always, always, always pinch off the pressure line while watching the tachometer. When it peaks at the same rpm twice, it's reached operating temperature, and it's then time to set the NV.  Steve

"A Trick , if on muffler pressure , Blocking the muffler exit / exits
if its giotta warm up - Block on & on . Blip Blip . Soon as theres
HEAT in the Engine , it usually becomes unesesary . So As To
AVOID having to Fiddle with the little tight needle up forward ,
Sometimes at the muffler side . Which isnt the best  as the
natural reaction to heat is to gettem ( fingers ) away from it .
As theyre boxed in by the muffler and prop , it can be awkward ."

[M Spencer]

Imagine it as a flute !

To Prime the motor - on muffler pressure - if you block the outlet - Bingo - Presurisd tank feeds intake .
Right. Flick it over & it pushes the  fuel UP to the Intake . as your swinging it over , itll pull it IN . ( Crankcase depression , you know . ) Suction some people call it . DONT take your finger OFF ,
doing this , as youll spoil the effect . TBlock , two or three swings ( of the prop ) to get a bit of pressure up . NO shilly Shallying !  then 2 to 5 swings more , on the prop , or the more cautious might use less .
IF its one of those planes where everythings innacessable   - your doing it to PRIME the fuel line  , so its not DRY and stalls . If you wish to Enrichen the intake , More is Required . YOU want MORE ( Oliver Twist ! )
Some engines ( not only engines !  ) are crankey . They want the needle OPENED to get more FUEL , untill theyve got Temperature ( 5 or ten seconds ) .

PRIMED , theyll start , then sag . MORE FUEL . Obviously it will stop if you dont exdigitate ,  In never said HOLD it there . Try morse code .  Tap tap tap ,
Or a Tune , if your musically inclined . The more dextorus will get two taps ( like a tap dancer - Not a Stomp dancer .  ) Castenettes Mate . Rattle rattle rattle )
Per SECOND - ish  .
Now , the correct - is two taps of the fingertip .- pause - two taps . Cripes thats three seconds - Its likely CLEARED by Now , and ready to chew your fingers -
If iit sags , a couple more - etc . 5 to 10 seconds . As I Said - And It should be all cossey!

It is to marginally richen it , if its cold blooded , in lieu of ALTERING the Needle , then realtering it .
Some people have been known to blow through a half metre of Neoprene tube - In FAI competion .
I kid you not.
In Team Race .
World Champions , Even .
I believe , the Metkemeyers . Obviously theres a technique involved . You dont just BLOW , an Art , even .
As they DONT want to loose their hard earned race setting . So Enrichen by pressuriseation .puff puff puff , with pauses . As Required  . Rim rim SNARLL . ( Diesels Snarl , you Know . High RPM ones ) *
We can emulate them , and have .
* RVD 's however , Go - Flick CLUNK , Flick CLUNK Flick , Yang Yang Yang  ( Warming up Yang Snarl Howl Whine . And they arnt even English ! . 
Very Appropriate to the topic . the Blood goes squirt squit squirt from the Chops on the back of the fingers .  Washing Machine Hose , the ribbed stuff , was the trick .
Actually - The Better Houses ( suppliers of T/R & combat gear , supply custom Finger Stalls . Better ones having a intregal strap - so It dost fly off in the excitement  ( The Combatt flyers tend to be exciteable )
 Just the Thing were LOOKING FOR , If your a Finger Man . I think most of the European Comp. Equip outfits carry them .      ( one thing leads to another , apparently    )
But the lazier or less well equipped , can achieve The Same RESULT  , By using the muffler outlet as a Flute . Like Man . 
Try it , Youll like it . You could even get a 4 - 2 switch , just sitting there . If Its Windy , you woulnt even need to fly . You could do a simulated engine run , on the Deck .*
DONT TELL ME , Youve NEVER seen anyone give it a tap or two , getting it underway ?  . Terrible . The young people these days . Why ? Whats the world coming to .        
  *  Might pay to wear a glove , if you want to do that , as it gets hot pretty smartly . Blokes whove done a lot of outside work have tougher hands than the indoorers .  Fingers too . 

[M Spencer]

Block on & on .

The More perceptive amougst us , might see , if you want to get it on , youve got to get it OFF , before you can get it on again .

If you can get this down , by heart , youll be right to go , first time. Straight Off . Without having to practise it first .


 
THIS is more in the Carp line than propellor . Flying ones Ive seen ( pictures of ) are one piece moulded neoprene or sumsuch , Bright DayGlo yellow/Green .- with a thong runnig aft from finger to wrist . So more asceticly pleasing, lighter, and comfortable . 



Whats really needed, is a Two Finger One . From a Brick Layer .



A Pessimist Sees the Difficulty in Every Opportunity; an Optimist Sees the Opportunity in Every Difficulty . W. S. Churchill .

[GERALD WIMMER]

Gerald Wimmer, would you PLEASE translate ....

Hello Yes the picture seems to be clear now , engines running muffler pressure can prime by blocking the exhaust momentarily.

I have to say running a bladder on a combat model makes fuel priming very simple but introduces a new hazard of spraying fuel and need for safety glasses I hate getting fuel in my eyes but cuts are worse... 

Regards Gerald