Why not a fan-style covering for props?

SkyHog

Touchdown! Greaser!
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Everything Offends Me
People die from being chewed up in a propeller.

Why can't we put a gate or something around the propeller that will allow taxi/ground runs, and possibly be retracted for flight (or not retracted at all?)

It'd still hurt to be hit by it, but it wouldn't kill ya.
 
Interesting thought Nick, I guess its a cost benefit thing. How many folks get whacked by a prop per year vs. the cost plus what Kent said.

I would think a visual warning would be more cost effective such as a paint scheme on the blade that made it visiable when spinning.
 
Interesting thought Nick, I guess its a cost benefit thing. How many folks get whacked by a prop per year vs. the cost plus what Kent said.

I would think a visual warning would be more cost effective such as a paint scheme on the blade that made it visiable when spinning.

which is why a lot of props have white/orange/yellow stripes painted on the tips.
 
People die from being chewed up in a propeller.

Why can't we put a gate or something around the propeller that will allow taxi/ground runs, and possibly be retracted for flight (or not retracted at all?)

It'd still hurt to be hit by it, but it wouldn't kill ya.

I'd like to see a line, icon, or arrows 6-18" from the props to remind us. Especially with how close we get trying to jump our planes.

Why not put them over Jet intakes too? Every field/hobby/occupation has some danger to it. We just have to mitigate the danger.
 
I'd like to see a line, icon, or arrows 6-18" from the props to remind us. Especially with how close we get trying to jump our planes.

Why not put them over Jet intakes too? Every field/hobby/occupation has some danger to it. We just have to mitigate the danger.


Military a/c have lines and warnings and cautions all over.

Kinda overhwelming and probably not even meaningful to the typical "walked into the prop" case, though.
 
Military a/c have lines and warnings and cautions all over.

Kinda overhwelming and probably not even meaningful to the typical "walked into the prop" case, though.

Exactly what I was thinking, but slightly subtle to not "clash" with individual paint jobs.

Also, our hobby/occupations isn't the only one with risk. Electricians carefully hand live wires all the time. Auto mechanics reach under the hood with radiator fans & belts going. Like them it's our duty to understand and mitigate the risk.
 
Interesting thought Nick, I guess its a cost benefit thing. How many folks get whacked by a prop per year vs. the cost plus what Kent said.

I would think a visual warning would be more cost effective such as a paint scheme on the blade that made it visiable when spinning.

I thought the nice loud noise they made was warning enough. Or the fact that you didn't see the blade sitting still.
 
I think something like this on the prop would let us display a warning:


... and totally impress the ladies.
-harry
 
I think something like this on the prop would let us display a warning:


... and totally impress the ladies.
-harry

Seriously - that would work. A simple "I'm spinning, Back off" would work.
 
People die from being chewed up in a propeller.

Why can't we put a gate or something around the propeller that will allow taxi/ground runs, and possibly be retracted for flight (or not retracted at all?)

It'd still hurt to be hit by it, but it wouldn't kill ya.

A lot of complication that can go wrong, a bunch of drag, a bunch of weight. Do we really need to lose another 100 lbs of our useful load? How many prop strikes against people are there? Some safety features just aren't worth it.

Just don't walk into the damn prop.
 
How about safety screens in front turbine intakes?

This guy got lucky, but a screen would have reduced his injuries.


Might have even stopped Sully from having to deal with a full on turbine failure.
 
How about safety screens in front turbine intakes?

This guy got lucky, but a screen would have reduced his injuries.


Might have even stopped Sully from having to deal with a full on turbine failure.

Too much drag and expense for too little return.
 
A lot of complication that can go wrong, a bunch of drag, a bunch of weight. Do we really need to lose another 100 lbs of our useful load? How many prop strikes against people are there? Some safety features just aren't worth it.

Just don't walk into the damn prop.

I agree 100%. But it would be nice to see avatars on the props so people could easily recognize others.:D

I guess if you see an airplane, hear the prop spin'n, you should assume that walk'n in front would be a bad idea. If not, well lets hope ya didn't reproduce.:rofl:
 
Should we have safety cages on jet's too? People don't walk into those, but get sucked in too.

Just don't walk into the damn prop.
Agreed, but that's not the way the world works IMO.

Once again, I think train vs. car collisions explains the issue. Trains are big, visible, travel predictable paths, and often makes lots of noise with the horn. Some of you may call those getting struck in those idiots.

The above wasn't enough so they put flashing lights at crossings. Then they designed arms (with flashing flights) to lower in front traffic. Still the trains rammed the cars that went around the gate. Now they've put an extra set of gates on the "wrong side" of the road to stop those cars plus cameras to issue tickets. Overkill for a simple problem with a simple solution, but it spills over into every part of life.
 
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How many people die from prop strikes each year? Not many I would wager.
 
How many people die from prop strikes each year? Not many I would wager.

And even cages cannot prevent problems.

http://footflyer.com/Safety/Incidents/2007-06-prop-strikes/prop-strikes.htm

One surprising incident happened to an experienced PPG3 pilot while forward launching in calm conditions on a rigid frame machine. According to USPPA's report, he "Began inflation, got pulled back, applied full power. Hands got pulled into reinforced rigid cage/netting, prop contacted left middle finger only." This is scary and gives a good reason to rethink our cage protection and prop clearance. In the meantime, rethink full power inflations although this one started out as a partial power inflation. Falling backwards on launch represents a risk because your instinct is to put your hands down and back—right into the prop. Very few cages have enough protection here. I know of two of these accidents and am told that one pilot still doesn't have use of the hand and that was 3 years ago.
 
Why can't we put a gate or something around the propeller that will allow taxi/ground runs, and possibly be retracted for flight (or not retracted at all?)
Aren't you one of the people who wants to make flying less expensive and more accessible to the common person? The cost/benefit ratio of whatever device you could come up with doesn't look too favorable to me, besides it seems like it would be an engineering nightmare. How would it be stowed in flight, and if you didn't stow it you would have a whole set of aerodynamic issues with prop since the tips create vortices too.
 
Proper aircraft operation helps. When dropping off or picking up passengers, SHUT IT DOWN, always.
 
Aren't you one of the people who wants to make flying less expensive and more accessible to the common person? The cost/benefit ratio of whatever device you could come up with doesn't look too favorable to me, besides it seems like it would be an engineering nightmare. How would it be stowed in flight, and if you didn't stow it you would have a whole set of aerodynamic issues with prop since the tips create vortices too.

I am. And I'm not proposing mandatory stuff.

Seems to me, a simple cage setup with slots cut into the cowling that the cage retracts into (simple pull of a cable) would do it.
 
I am. And I'm not proposing mandatory stuff.

Seems to me, a simple cage setup with slots cut into the cowling that the cage retracts into (simple pull of a cable) would do it.

Can you show me where there is room in the cowling of most airplanes for such things? How about the cooling issues created by shoving more stuff in there and interfeering with teh airflow?

It would take some serious modificatons to implement. After that you'll have to come up with STC's to implement this on airframes (good luck).

It just isn't realistic.
 
There isn't room for anything in my Tiger's cowling, nor a Mooney's nor an RV. Ain't gonna happen.
 
Isn't it mostly PILOTS who end up injured/killed in prop-strikes?
Exiting planes that they've left running?
Or, getting struck while hand-propping?

(I haven't done a review of incidents. Just seems like most that I've read about have pilots as "victims.")
 
I am. And I'm not proposing mandatory stuff.

Seems to me, a simple cage setup with slots cut into the cowling that the cage retracts into (simple pull of a cable) would do it.

That doesn't sound simple at all! How do you get the parts of the cage that are in front of the prop to retract all the way around the outside and then into the cowling? And if they're flexible enough to do so, they'd make a crappy cage anyway...
 
Isn't it mostly PILOTS who end up injured/killed in prop-strikes?
Good point. maybe we should ban pilots from being close to airplanes??!!!

Could work.

I heard once that most accidents occur in the home, so I moved and have not had an accident. Same theory for the prop thingy. ;)
 
I am. And I'm not proposing mandatory stuff.

Seems to me, a simple cage setup with slots cut into the cowling that the cage retracts into (simple pull of a cable) would do it.

Nick, I gave this a few moments of serious thought and concluded that there's just no way you could make anything which would "retract into the cowl" and be strong enough to do any good (has to withstand the force of a body walking into it aided by the airflow from the prop) without making the cowling at least twice as big as it is and adding at least a hundred pounds or two. Just moving something from the front of the prop to behind it without risking contact with the prop (and associated costly damage) would require something pretty fancy. And given the market for such a device, you'd probably be talking of around $200,000 installed.

I think that nuclear powered Ion propulsion for GA is likely to become available first.
 
Nick, I gave this a few moments of serious thought and concluded that there's just no way you could make anything which would "retract into the cowl" and be strong enough to do any good (has to withstand the force of a body walking into it aided by the airflow from the prop) without making the cowling at least twice as big as it is and adding at least a hundred pounds or two. Just moving something from the front of the prop to behind it without risking contact with the prop (and associated costly damage) would require something pretty fancy. And given the market for such a device, you'd probably be talking of around $200,000 installed.

There's much talk about how to make flying cheaper. Suggesting cages for props takes things the other way, big time. If the government decided to mandate cages, we might as well give up flying. The weight, complexity and resultant cost would ruin the airplane and it would never sell. And its prop would therefore never kill anyone, either. Mission accomplished.

Jets don't use screens because of the drag and the problem of ice accumulation. The ice would either choke off the airflow, or break off and go into the engine and bust things. Heating that screen would cost a huge part of the engine's power. It already costs plenty to heat the inlet lip and fan hub.

Small ducted fans, of the size we'd use with piston engines, have seldom worked well at all. Too much drag, and losses associated with small diameters and high RPMs. On turbofans they are large, and the duct is to slow the incoming air to increase its pressure. That isn't necessary on a small piston-powered fan.

It comes down to one thing: Don't Be Stupid. Don't let the uninformed near running airplanes. Don't let dogs or kids run loose around airplanes. Never board or deplane people with the engine running. Don't hand-prop unless you know the hazards and have some training.

What's next? Cages under the lawnmower blade to keep guys from running over their feet or sticking their hands underneath to clear the clogged grass? Electronic finger detectors and superfast brakes for skilsaws? A cancer vaccine added to every cigarette?

Dan
 
It comes down to one thing: Don't Be Stupid. Don't let the uninformed near running airplanes. Don't let dogs or kids run loose around airplanes. Never board or deplane people with the engine running. Don't hand-prop unless you know the hazards and have some training.

Don't name the airport dog "Clear!" :no:

What's next? Cages under the lawnmower blade to keep guys from running over their feet or sticking their hands underneath to clear the clogged grass?

The Wisconsin Supreme Court had a case today involving a father who had backed over his son with the John Deere and cut the poor kid's feet off, and then sued John Deere for not automatically shutting down the mower deck when the tractor was put in reverse.

The case was thrown out. Finally, some common sense in the courts! :yes:
 
Proper aircraft operation helps. When dropping off or picking up passengers, SHUT IT DOWN, always.

+1

Always!

We had a flying farmer have his son get out of the plane to open a gate. The kid ran right though the prop. We are just so used to working around planes with the engine off and walking through the ark that when it is turning some people forget for a split second what they are doing... and die.
 
Getting shwacked by a spinning prop is Darwinian elimination...too stupid to survive. The world is overpopulated because we protect the weak and stupid, therefor the weak and stupid repopulate some more. We're running out of fresh water, time to start the culling, not add more protection.
 
Getting shwacked by a spinning prop is Darwinian elimination...too stupid to survive. The world is overpopulated because we protect the weak and stupid, therefor the weak and stupid repopulate some more. We're running out of fresh water, time to start the culling, not add more protection.

Humans have had how many millenia to improve?

Darwin doesn't account for the human ability to invent new ways to die.
 
Humans have had how many millenia to improve?

Darwin doesn't account for the human ability to invent new ways to die.

As a species we peaked around 50 years ago. Darwin of course accounts for our own invented ways to die. If the "strong" of the species (strength can be mental rather than physical) create things and the "weak" can't figure out how to keep from getting killed by it, the genetic sequence that makes them stupid gets to die with them, hopefully before they get a chance to breed, unless of course we convert to a Soilent economy, then the stupid will be like Doritios, "Crunch all you want, we'll make more..."
 
+1 to what Jesse said, 100%.
 
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