Good Aviation Ideas
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Good Aviation Ideas
I got an inspiration for this topic from a post in the Rumors and News forum.
I read a good article the other day about ground personnel accidents that happen when ground personnel back into or walk into rotating propellers, nearly always resulting in deaths. It's believed that most of these accidents occur because the ground personnel momentarily forget the danger of the propellers, or while distracted (with ear protectors on), fail to see the propellers because it's hard to see them when they're spinning, especially at night.
The author liked the old military idea of painting a vertical line on the side of the fuselage adjacent to the propeller, so that ground personnel would be visually reminded of the propeller arc by seeing the bold vertical line. I think this is good, but might not be as effective at night where a lot of the accidents occur.
My idea is to use a powerful strobe light aimed directly at the propeller. Many aircraft now have lights embedded in the side of the fuselage that point toward and illuminate the leading of the wing. I think this idea can be taken a step further with embedded strobe lights aimed at the propellers.
You know how strobes have the ability to visually "freeze" the motion of a moving object especially a spinning one, and each flash "freeze" shows the object in a different position from the last flash "freeze". This property of strobe lights has the ability to "show" the spinning propeller when otherwise it's hard to see.
Powerful strobes could work in both daylight and darkness (especially in darkness), and the strobes could be on only when the aircraft is on the ground in a terminal area with the engines running (where ground personnel are). I think this would help ground personnel "see" the propeller much better, and the flashing strobes would always be a reminder of the danger of the propellers.
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Safe flying to you...
I read a good article the other day about ground personnel accidents that happen when ground personnel back into or walk into rotating propellers, nearly always resulting in deaths. It's believed that most of these accidents occur because the ground personnel momentarily forget the danger of the propellers, or while distracted (with ear protectors on), fail to see the propellers because it's hard to see them when they're spinning, especially at night.
The author liked the old military idea of painting a vertical line on the side of the fuselage adjacent to the propeller, so that ground personnel would be visually reminded of the propeller arc by seeing the bold vertical line. I think this is good, but might not be as effective at night where a lot of the accidents occur.
My idea is to use a powerful strobe light aimed directly at the propeller. Many aircraft now have lights embedded in the side of the fuselage that point toward and illuminate the leading of the wing. I think this idea can be taken a step further with embedded strobe lights aimed at the propellers.
You know how strobes have the ability to visually "freeze" the motion of a moving object especially a spinning one, and each flash "freeze" shows the object in a different position from the last flash "freeze". This property of strobe lights has the ability to "show" the spinning propeller when otherwise it's hard to see.
Powerful strobes could work in both daylight and darkness (especially in darkness), and the strobes could be on only when the aircraft is on the ground in a terminal area with the engines running (where ground personnel are). I think this would help ground personnel "see" the propeller much better, and the flashing strobes would always be a reminder of the danger of the propellers.
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Safe flying to you...
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FS,
I feel that stobes would be more of a safety hazard than help.
In industry stobes are used to test the frequency of rotating objects, motors etc. When the two are in sync the motor appears stationary etc, this is where the eye takes over and leaves the mind behind (similar to spatial disorientation etc.) we believe what our eyes see, despite our better judgement. In industry all to many fitters / engineers and countless more apprentices have fallen foul of this. It is what has given rise to the use of task lighting, as the flicker of flourescant tubes has tricked operatives into beliving rotating equipment is stationary.
I do take the point that the prop spinning and flashing strobe will give rise to several stationary shots of the prop, however when the two are in sync the prop will appear completly still and as in industry can have horrendous implications.
VF
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GAA, I thought of that, and thought that maybe ground personnel would have to be asked if they had any medical limitations when hired that would prevent them from performing their duties, including flash induced epilepsy.
VF, your point I hadn't thought of. If the strobe frequency were slow enough (like 2 times per second) would this prevent the propeller from appearing to be stationary, even if the prop and strobes were in sync? Suppose that operational procedures were established that required that the strobes be turned on only while the props were turning, would this be sufficient to establish a clear unmistakable association between the flashing strobes and propeller danger? Would this association be strong enough that it would not be forgotten by ground personnel, even if a slow frequency flash were used, and the prop and flash were in sync?
What effect would a combination of standard light illumination and a slow frequency strobe illumination of the propeller have?
GTE, I believe the author of the article referenced that report. He felt that while those paint schemes helped, they still didn't prevent all of the accidents.
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Safe flying to you...
[This message has been edited by Flight Safety (edited 05 April 2001).]
VF, your point I hadn't thought of. If the strobe frequency were slow enough (like 2 times per second) would this prevent the propeller from appearing to be stationary, even if the prop and strobes were in sync? Suppose that operational procedures were established that required that the strobes be turned on only while the props were turning, would this be sufficient to establish a clear unmistakable association between the flashing strobes and propeller danger? Would this association be strong enough that it would not be forgotten by ground personnel, even if a slow frequency flash were used, and the prop and flash were in sync?
What effect would a combination of standard light illumination and a slow frequency strobe illumination of the propeller have?
GTE, I believe the author of the article referenced that report. He felt that while those paint schemes helped, they still didn't prevent all of the accidents.
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Safe flying to you...
[This message has been edited by Flight Safety (edited 05 April 2001).]
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FS,
1 )If the strobe frequency were slow enough...
Yes, if it were slow enough and the rotation speed was fixed the strobe would work, i.e several positions per second giving the apearance of a slower rotation. However for manouvering the prop will be advanced thus increasing the rotations and back to square one... a variable resistor tied into the throttle control or rev counter might solve that one.
2)Would this association be strong enough that it would not be forgotten by ground personnel....
Proceedures would have to be very clear and strictly abided by, but I would add that on an airfield there are strobes every where wing tips etc, Would ground crew consider another flashing strobe as a passing AC ?
I would love to hear a ground ops take on this?
Where would you mount the strobes?
1 )If the strobe frequency were slow enough...
Yes, if it were slow enough and the rotation speed was fixed the strobe would work, i.e several positions per second giving the apearance of a slower rotation. However for manouvering the prop will be advanced thus increasing the rotations and back to square one... a variable resistor tied into the throttle control or rev counter might solve that one.
2)Would this association be strong enough that it would not be forgotten by ground personnel....
Proceedures would have to be very clear and strictly abided by, but I would add that on an airfield there are strobes every where wing tips etc, Would ground crew consider another flashing strobe as a passing AC ?
I would love to hear a ground ops take on this?
Where would you mount the strobes?
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VF, I walked around 2 Lear Jets (models 45 and 60) the other day, and one of them had lights embedded (beneath the surface) in the side of the fuselage ahead of the wing leading edge, aimed back at roughly 45 degrees through a small flush mounted window, at the leading edge of the wing. The purpose was to illuminate the wing leading edge (to check for ice accumulation?). Anyway, the installation was flush against the side of the fuselage, and was therefore aerodynamically clean.
This same type of installation would work for this application, with the strobe installed ahead of the wing (embedded in the side of the fuselage in the exact same manner as I observed on the Learjet) aimed back at the prop disk.
I agree that a very simple electronic device could also be included that regulates a slow flash frequency in relation to prop speed, so flash syncing does not occur.
I would also love to hear from ground ops personnel on this.
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Safe flying to you...
[This message has been edited by Flight Safety (edited 05 April 2001).]
This same type of installation would work for this application, with the strobe installed ahead of the wing (embedded in the side of the fuselage in the exact same manner as I observed on the Learjet) aimed back at the prop disk.
I agree that a very simple electronic device could also be included that regulates a slow flash frequency in relation to prop speed, so flash syncing does not occur.
I would also love to hear from ground ops personnel on this.
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Safe flying to you...
[This message has been edited by Flight Safety (edited 05 April 2001).]
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I think it would be quite easy to synchronize a strobe light such that the propeller appeared to be spinning at, say, 100 to 150 RPM, so still visible but much too fast to be comfortable near. The strobes themselves could be ducted such that they were not directly visible (unless looking into the duct!) so reducing the possiblity of strobe-induced epilepsy.
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Technically there is no end to the number of solutions for this problem, including aformentioned rpm input to the strobe light.
But I belive that most accidents involving propellers araise from a number of factors, but most often fattigue and stress(incl. noise). This is not ment in any way to be pilot bashing, but pilots have working time regulations that not only limits the amount of hours in a day, but also over a given period. A similar solution for ALL ground personell would most likely erradicate most of these incidents and accidents, the only problem being, who would pay for it. But then again, nobody put a price on safety, do they.
Brgds
Doc
But I belive that most accidents involving propellers araise from a number of factors, but most often fattigue and stress(incl. noise). This is not ment in any way to be pilot bashing, but pilots have working time regulations that not only limits the amount of hours in a day, but also over a given period. A similar solution for ALL ground personell would most likely erradicate most of these incidents and accidents, the only problem being, who would pay for it. But then again, nobody put a price on safety, do they.
Brgds
Doc
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I have worked as a handler and the one thing we need to avoid such accidents is - time. Normal procedures are to go nowhere near the plane before all propellers are stopped and no strobes are flashing. Actually we were not even allowed to go through the propeller arc when the engines were stopped.
However, it is a rather rushed environment and when you have an arrival and then another plane to attend to twenty minutes later, well... the temptation to get those stairs in place and the GPU connected before the propeller has stopped is there.
Also, some captains have this habit of leaving (forgetting?) the strobes on for a long time and then complaining that we don't get them on the blocks fast enough - since we are waiting for them to turn off the strobes. My company was very understanding about this but I can imagine that handlers elsewhere are less fortunate in this respect. Also, again there's often the problem that another arrival or departure is scheduled just after you have taken care of the current one so you don't want to be standing around doing nothing.
I would have hated to have strobes running in the vicinity while at work. It is rather stressful. There are enough flashing lights on the ramp already. Besides, I think the ground controllers and the tower would have a thing or two to say about having aircraft all over their ramps strobe illuminated.
All in all, thanks for your concern for our safety but, as with many human factors issues, technical solutions will do nowhere near as much good as a more relaxed work situation.
Cheers,
/ft
However, it is a rather rushed environment and when you have an arrival and then another plane to attend to twenty minutes later, well... the temptation to get those stairs in place and the GPU connected before the propeller has stopped is there.
Also, some captains have this habit of leaving (forgetting?) the strobes on for a long time and then complaining that we don't get them on the blocks fast enough - since we are waiting for them to turn off the strobes. My company was very understanding about this but I can imagine that handlers elsewhere are less fortunate in this respect. Also, again there's often the problem that another arrival or departure is scheduled just after you have taken care of the current one so you don't want to be standing around doing nothing.
I would have hated to have strobes running in the vicinity while at work. It is rather stressful. There are enough flashing lights on the ramp already. Besides, I think the ground controllers and the tower would have a thing or two to say about having aircraft all over their ramps strobe illuminated.
All in all, thanks for your concern for our safety but, as with many human factors issues, technical solutions will do nowhere near as much good as a more relaxed work situation.
Cheers,
/ft
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Interesting point along this thread is the use of ear defenders. After one particularly scary situation I was in I stopped wearing ear defenders on the ramp.
Engineers were ground running and did not have the strobe on. There were other aircraft running in the vicinity and I had on a pair of very good ear defenders. Cocooned in my deaf little world feeling safe and not very alert I only noticed the engines were running when the wind suddenly picked up to a frightening gale and became very warm. I had walked behind a running engine- god knows what would have happened if I had walked in front of it.
The moral of this story is I would much rather be deaf later on in life than chopped into tiny little pieces on an aircraft ramp!!
Needless to say I had a little chat with the safety man afterwards who had missed the whole entire event for some reason. He doesn't miss much now.
Engineers were ground running and did not have the strobe on. There were other aircraft running in the vicinity and I had on a pair of very good ear defenders. Cocooned in my deaf little world feeling safe and not very alert I only noticed the engines were running when the wind suddenly picked up to a frightening gale and became very warm. I had walked behind a running engine- god knows what would have happened if I had walked in front of it.
The moral of this story is I would much rather be deaf later on in life than chopped into tiny little pieces on an aircraft ramp!!
Needless to say I had a little chat with the safety man afterwards who had missed the whole entire event for some reason. He doesn't miss much now.
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SGB, I wonder if ear protectors could be designed so that you could still hear the engines running, but at much lower sound levels? I'd hate to see anyone lose their hearing over this.
I'm a sportsman and I shoot rifles on occasion, and the ear protectors used allow you to carry on a normal conversation, and also allow you to hear a rifle shot when it's fired. But the design of the protectors is such that the shot's noise is sufficiently suppressed to protect your ears, while still allowing you to hear the shot, and normal conversation. Clever design really.
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Safe flying to you...
[This message has been edited by Flight Safety (edited 09 April 2001).]
I'm a sportsman and I shoot rifles on occasion, and the ear protectors used allow you to carry on a normal conversation, and also allow you to hear a rifle shot when it's fired. But the design of the protectors is such that the shot's noise is sufficiently suppressed to protect your ears, while still allowing you to hear the shot, and normal conversation. Clever design really.
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Safe flying to you...
[This message has been edited by Flight Safety (edited 09 April 2001).]
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Coming in in the middle, but...
Why not use some kind of illumintation at the prop tip, so that at night the movement of the light traces an arc in the sky? This would show a large circle where the prop was spinning, as opposed to two/three/four points of light when the prop is stationary. Obviously this would only work at night, apart from really bright lights, and actually illuminating the tip could be difficult structurally (fibre optics?), but it could be a solution...
-tacc
[This message has been edited by Teenyweeny ATC Cdt Cpl (edited 09 April 2001).]
Why not use some kind of illumintation at the prop tip, so that at night the movement of the light traces an arc in the sky? This would show a large circle where the prop was spinning, as opposed to two/three/four points of light when the prop is stationary. Obviously this would only work at night, apart from really bright lights, and actually illuminating the tip could be difficult structurally (fibre optics?), but it could be a solution...
-tacc
[This message has been edited by Teenyweeny ATC Cdt Cpl (edited 09 April 2001).]
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That's what I was going to say Cadet Corporal! A little LED at the tip would be ideal, centrifugal force makes two electrical contacts inside the blade touch.
Battery powered or even better some conducting bushes at the hub to the aircraft's electrical system, positive and negative separated front and back.
I had another idea for the people at 3M. Could they invent a material suitable for use as a paint or a sticker that converts some kinetic energy (at the prop tip) to light energy? Or use the friction to warm something up and it glows, something like that?
My first thought was convert it to sound, but the only way I could think of was to put whistles on the tips and I know this slowed my frisbee down so much it didn't make it across the river one day. Plus it would be reaaaalllllyy noisy!
Battery powered or even better some conducting bushes at the hub to the aircraft's electrical system, positive and negative separated front and back.
I had another idea for the people at 3M. Could they invent a material suitable for use as a paint or a sticker that converts some kinetic energy (at the prop tip) to light energy? Or use the friction to warm something up and it glows, something like that?
My first thought was convert it to sound, but the only way I could think of was to put whistles on the tips and I know this slowed my frisbee down so much it didn't make it across the river one day. Plus it would be reaaaalllllyy noisy!
