Nice tutorial. You hit all of the important points quite nicely. The manufacturer states exactly how much of a tip load is allowed and it is crazy easy to exceed those numbers. But I've also seen other departments use these sticks to perform pick and lift operations starting from a fully extended ladder at a negative incline. Thanks goodness it worked. Well done.
Cool vid, thanks for sharing. I’m assuming some of the “do’s and don’t” are manufacturer/ AHJ specific, as we utilize both a pierce heavy duty steel platform, and an ascendant aerial, and Pierce recommends doing a fixed pickoff as opposed to using it as a high directional, although we’ll train on both.
I would assume that your assumptions could be correct. I don't know if there are any manufacturers that will publish any tables or info on using these as high directionals because it's so variable & dynamic based on magnitude & direction of the resultant as a function of aerial angle & aerial extension. I think that training on both is a good thing because our environment is too dynamic & unpredictable to arbitrarily cross one option completely off the table & say "never". Different techniques are like having more tools in the toolbox... It's always better to have a multitude of options. But it's on us to select the best ones for the specific task & make informed decisions based on pros vs cons, & risk-reward analysis.
Does the OSHA regulation pertain to attempting to move the aerial when we have a long haul system rigged or would it technically apply to a short haul system as well? Using an aerial device as a high directional does not load it as intended where as a short haul loads the tip in a vertical orientation which is inline with the manufacturers tip load.@@Propeller_Head
The regulation pertains to the dangers of operating the hydraulic systems when live loads are suspended & does not address specific types of rope systems. So it doesn't matter what kind of haul or lowering system you have. I'm confused on your terminology of "short haul". Can you explain what you mean by that? Just like velocity has both a speed and a corresponding direction, a load, wether it is directly off the tip of an aerial or through a high directional, will create a force vector that has both magnitude and direction. If you suspend a load directly off the tip, there are two aspects of force to consider (and this is typically accounted for in the aerial tip load charts based on the angle of the stick and the extension, or length of the lever). The first is the net force of the load itself that points directly down. The second is the torque effect that the load imparts onto the fulcrum of the giant class 3 lever (that is the aerial ladder at its base where the hydraulic rams are). The longer the ladder (more extension) and shallower the angle, the less tip load capacity, regardless of if it's a directional or if a load is suspended directly underneath. However, the tip load charts do not account for the force amplification effects of a directional anchor. Interpreting these effects are the job of the rope rescue practitioner. Quick case analysis: If you extended the ladder out to full extension and the angle was flat to the horizon, then suspended a load vertically through a 90 degree directional, then there would be a net resultant force acting on the tip. This force value is 141% of the suspended load, but the direction of that force is 45 degrees closer to the structural frame of the ladder which helps reduce/mitigate the force amplification that is seen at the fulcrum. On the flipside, if the load were suspended directly from the tip, then the net force is less at 100%, but the resultant force direction is 90 degrees away from the structural frame of the ladder which increases the torque at the fulcrum. To further make things worse, when you apply practical rigging to this equation, there are three common options to either lower or haul a load that is suspended from the tip. The first is to have a rescuer at the tip operating a lowering device. This setup doubles the tip load because there's now two people @ the tip... so 200% force amplification in a straight downward direction which is not ideal. The other common setup is when you rig a 4:1 block & tackle system onto the tip & operate it from the ground. This creates a 125% amplification of the force in a straight downward direction, also not ideal. The third is to use the tip as a directional but the line routes a full 180 degree bend so that the source of the haul is straight down. This also creates 200% force amplification in a straight downward direction. Routing the line along the frame of the ladder and through a high directional, while you do amplify the force of the load, you also are moving the direction of the net resultant force closer to the frame which eases the torque forces at the base of the ladder. And this is the critical part of using the aerial. The weak point in this system is the invisible torque effect that can occur at the base of the aerial, not so much the load at the tip. So doing whatever you can to mitigate that weak link is paramount.
What is the tip load for your aerial? I noticed the bolt on was really small and that's where the common "tip load" is referred to so is where you're placing the webbing technically a higher load capacity?
There are max load placards located at each welded eyelet that is part or the aerial frame. Each eyelet on our aerial says “Max 250 lbs”. Yes, if you elect to rig webbing around the aerial rails then I would argue that your capacity “could” be more than if you were rigging to just the eyelets. Rigging anything to the aerial beyond those small bolts is a No-Go.
Thanks. Unfortunately we didn’t have enough rope length to put a block in…. We had to park the ambo that close just to be able to anchor the MPDs & give us just enough throw to start a haul
I have been watching many of your videos and have enjoyed the straight forward, direct approach. Very good info presented. Being on the East Coast I like the West Coast and RTR influence. You don't get a lot of that over here. As a far as this video goes; it's my opinion that this topic is very polarizing and often misunderstood and misapplied. This definitely can go beyond the basic understanding of many rank and file FFs, myself included at times. Are you familiar with the testing that Kelly Burne out of DC did for the ITRS on this? Also the CMC guys (also Kelly) did a podcast on the subject. They had some interesting results. I would welcome your thoughts specifically on the idea that the aerial device should be though of as a truss and not a column, therefore the idea of pulling in line may not be the best. Thanks again.
Thanks! Truss vs. a Compression Member? I’m at a loss. My gut feeling is that you can’t have your cake & eat it too, & there’s always going to be some kind of tradeoff or compromise when trying to rig aerials safely, or with some sort of confidence in your perceived ability to know what you’re doing & why…. & where the weak links exist. So I don’t have any solid opinion on it as of yet. Most of the issues that were brought up in that CMC podcast resonate with me & for the most part I agree with what was discussed. I’m personally leaning towards AHD as opposed to using a B&T system at the tip, but thats because the lens I’m looking through favors crane rigging theory. While a B&T does minimize the tip load, I just think it’s less practical than the AHD route.
Your 1st evolution. Try lowering your patient as a skateblock system and ditch the tag line. It works really good. Get some load cells. I'd be interested in your readings. Something else you can try is get truck scales like PD used to weigh trucks. Put them under the outriggers. Get baseline reading with no load at all extension and rotation. Then do readings while FFers are climbing and doing normal firefighting tasks like roof vent etc. after all that then do rope work and see what you came up with. I've done a little backyard testing doing these things and have a few numbers. Your doing cool stuff keep it up.
I think there will be a lot of variance in field testing with load cells. For example, an inconsistent or jerky haul input will tend to spike the forces. Also, the characteristics of the high directional pulley & interface with the rope will play a factor as well. Can’t forget about stick oscillations due to wind either. But in theory using ballpark math if I have a 225 lb load on a line going through a steep angle high point then the load cell would read 450 lbf in a static state. Without any oscillations & a smooth & consistent hauling input through a 90% efficient pulley, then I would expect an additional 10% (or 22.5 lbf) at the load cell in order to overcome friction. So best case I’m seeing 472.5 lbf at the tip for a 225 lb load. What numbers are you getting & with what type of pulley? Also what are the characteristics of the hauling input? Or are you talking about the force seen at the outriggers? In which case I believe you when you say that the forces there are so great, due to the torque effect.
you should really think about attaching yourself somewhere else safer. your side loading that carabiner and your also clipped in on the gate side which is a huge mistake. there is hardware out there you can get to simplify that mess of knots and carabiners. I would suggest looking into a rigging plate which would be safer and quicker.
I appreciate your feedback and insight, & I went back through this video in an attempt to identify the issues & mistakes you pointed out but I’m just not seeing what you’re seeing. Could you provide me a timeframe (minutes & seconds) where you saw these errors so I can look further? As far as the rigging plate goes… opinions vary & I fully understand that many practitioners out there like using rigging plates. I also like using them, but I prefer to reserve them for places at the anchors. When rigging the rescue package end of rope systems, I tend to default to a “low-profile” philosophy & try to reduce the profile of the master attachment point, thus the bowline knot to act as the “yoke” or “MAP”. “Quicker” & “Safer” are subjective & relative terms to be left for interpretation by the individuals & teams that choose to employ certain rigging methods over others. For me & my team, we would argue that it is quicker & safer to use the double long tail bowline rather than incorporating a rigging plate. For us, a rigging plate is just an extra piece of gear that we don’t need & just eats up additional real-estate in terms of height clearances. To quote a mentor of mine, “simplicity & complexity are not technique issues, rather they are training issues. What can be seemingly complex for some teams may be relatively simple for others.”
This channel is incredibly underrated. As a brazilian firefighter, It's really hard to find content with that much knowledge. Keep up the good work!
Thanks, much appreciated!
Nice tutorial. You hit all of the important points quite nicely. The manufacturer states exactly how much of a tip load is allowed and it is crazy easy to exceed those numbers. But I've also seen other departments use these sticks to perform pick and lift operations starting from a fully extended ladder at a negative incline. Thanks goodness it worked.
Well done.
Thanks!
Nicely done! The terrain and the churches in the background looks like Utah, am I right? Haha
It's actually Undefine Academy footage. They have a channel as well
Cool vid, thanks for sharing. I’m assuming some of the “do’s and don’t” are manufacturer/ AHJ specific, as we utilize both a pierce heavy duty steel platform, and an ascendant aerial, and Pierce recommends doing a fixed pickoff as opposed to using it as a high directional, although we’ll train on both.
I would assume that your assumptions could be correct. I don't know if there are any manufacturers that will publish any tables or info on using these as high directionals because it's so variable & dynamic based on magnitude & direction of the resultant as a function of aerial angle & aerial extension. I think that training on both is a good thing because our environment is too dynamic & unpredictable to arbitrarily cross one option completely off the table & say "never". Different techniques are like having more tools in the toolbox... It's always better to have a multitude of options. But it's on us to select the best ones for the specific task & make informed decisions based on pros vs cons, & risk-reward analysis.
What is the OSHA regulation that you are referring to?
29 CFR 1910.180 (Crawler Locomotive & Truck Cranes)... [h.3.iii.v]
Thanks!
Does the OSHA regulation pertain to attempting to move the aerial when we have a long haul system rigged or would it technically apply to a short haul system as well? Using an aerial device as a high directional does not load it as intended where as a short haul loads the tip in a vertical orientation which is inline with the manufacturers tip load.@@Propeller_Head
The regulation pertains to the dangers of operating the hydraulic systems when live loads are suspended & does not address specific types of rope systems. So it doesn't matter what kind of haul or lowering system you have. I'm confused on your terminology of "short haul". Can you explain what you mean by that?
Just like velocity has both a speed and a corresponding direction, a load, wether it is directly off the tip of an aerial or through a high directional, will create a force vector that has both magnitude and direction.
If you suspend a load directly off the tip, there are two aspects of force to consider (and this is typically accounted for in the aerial tip load charts based on the angle of the stick and the extension, or length of the lever). The first is the net force of the load itself that points directly down. The second is the torque effect that the load imparts onto the fulcrum of the giant class 3 lever (that is the aerial ladder at its base where the hydraulic rams are). The longer the ladder (more extension) and shallower the angle, the less tip load capacity, regardless of if it's a directional or if a load is suspended directly underneath. However, the tip load charts do not account for the force amplification effects of a directional anchor. Interpreting these effects are the job of the rope rescue practitioner.
Quick case analysis: If you extended the ladder out to full extension and the angle was flat to the horizon, then suspended a load vertically through a 90 degree directional, then there would be a net resultant force acting on the tip. This force value is 141% of the suspended load, but the direction of that force is 45 degrees closer to the structural frame of the ladder which helps reduce/mitigate the force amplification that is seen at the fulcrum. On the flipside, if the load were suspended directly from the tip, then the net force is less at 100%, but the resultant force direction is 90 degrees away from the structural frame of the ladder which increases the torque at the fulcrum. To further make things worse, when you apply practical rigging to this equation, there are three common options to either lower or haul a load that is suspended from the tip. The first is to have a rescuer at the tip operating a lowering device. This setup doubles the tip load because there's now two people @ the tip... so 200% force amplification in a straight downward direction which is not ideal. The other common setup is when you rig a 4:1 block & tackle system onto the tip & operate it from the ground. This creates a 125% amplification of the force in a straight downward direction, also not ideal. The third is to use the tip as a directional but the line routes a full 180 degree bend so that the source of the haul is straight down. This also creates 200% force amplification in a straight downward direction.
Routing the line along the frame of the ladder and through a high directional, while you do amplify the force of the load, you also are moving the direction of the net resultant force closer to the frame which eases the torque forces at the base of the ladder. And this is the critical part of using the aerial.
The weak point in this system is the invisible torque effect that can occur at the base of the aerial, not so much the load at the tip. So doing whatever you can to mitigate that weak link is paramount.
What is the tip load for your aerial? I noticed the bolt on was really small and that's where the common "tip load" is referred to so is where you're placing the webbing technically a higher load capacity?
There are max load placards located at each welded eyelet that is part or the aerial frame. Each eyelet on our aerial says “Max 250 lbs”. Yes, if you elect to rig webbing around the aerial rails then I would argue that your capacity “could” be more than if you were rigging to just the eyelets. Rigging anything to the aerial beyond those small bolts is a No-Go.
Enjoy the videos very much. Having the ambulance so close you should have rigged the front with a block for the crew pulling
Thanks. Unfortunately we didn’t have enough rope length to put a block in…. We had to park the ambo that close just to be able to anchor the MPDs & give us just enough throw to start a haul
I have been watching many of your videos and have enjoyed the straight forward, direct approach. Very good info presented. Being on the East Coast I like the West Coast and RTR influence. You don't get a lot of that over here.
As a far as this video goes; it's my opinion that this topic is very polarizing and often misunderstood and misapplied. This definitely can go beyond the basic understanding of many rank and file FFs, myself included at times.
Are you familiar with the testing that Kelly Burne out of DC did for the ITRS on this? Also the CMC guys (also Kelly) did a podcast on the subject.
They had some interesting results. I would welcome your thoughts specifically on the idea that the aerial device should be though of as a truss and not a column, therefore the idea of pulling in line may not be the best.
Thanks again.
Thanks! Truss vs. a Compression Member? I’m at a loss. My gut feeling is that you can’t have your cake & eat it too, & there’s always going to be some kind of tradeoff or compromise when trying to rig aerials safely, or with some sort of confidence in your perceived ability to know what you’re doing & why…. & where the weak links exist. So I don’t have any solid opinion on it as of yet. Most of the issues that were brought up in that CMC podcast resonate with me & for the most part I agree with what was discussed. I’m personally leaning towards AHD as opposed to using a B&T system at the tip, but thats because the lens I’m looking through favors crane rigging theory. While a B&T does minimize the tip load, I just think it’s less practical than the AHD route.
Thanks for the response. We definitely have work to do on this topic.. @@Propeller_Head
Love it
I love that you love it
Your 1st evolution. Try lowering your patient as a skateblock system and ditch the tag line. It works really good. Get some load cells. I'd be interested in your readings. Something else you can try is get truck scales like PD used to weigh trucks. Put them under the outriggers. Get baseline reading with no load at all extension and rotation. Then do readings while FFers are climbing and doing normal firefighting tasks like roof vent etc. after all that then do rope work and see what you came up with. I've done a little backyard testing doing these things and have a few numbers. Your doing cool stuff keep it up.
Thanks!
@@Propeller_Head we have done this with load cells. It increases the load a lot more than you realize.
I think there will be a lot of variance in field testing with load cells. For example, an inconsistent or jerky haul input will tend to spike the forces. Also, the characteristics of the high directional pulley & interface with the rope will play a factor as well. Can’t forget about stick oscillations due to wind either. But in theory using ballpark math if I have a 225 lb load on a line going through a steep angle high point then the load cell would read 450 lbf in a static state. Without any oscillations & a smooth & consistent hauling input through a 90% efficient pulley, then I would expect an additional 10% (or 22.5 lbf) at the load cell in order to overcome friction. So best case I’m seeing 472.5 lbf at the tip for a 225 lb load. What numbers are you getting & with what type of pulley? Also what are the characteristics of the hauling input? Or are you talking about the force seen at the outriggers? In which case I believe you when you say that the forces there are so great, due to the torque effect.
you should really think about attaching yourself somewhere else safer. your side loading that carabiner and your also clipped in on the gate side which is a huge mistake. there is hardware out there you can get to simplify that mess of knots and carabiners. I would suggest looking into a rigging plate which would be safer and quicker.
I appreciate your feedback and insight, & I went back through this video in an attempt to identify the issues & mistakes you pointed out but I’m just not seeing what you’re seeing. Could you provide me a timeframe (minutes & seconds) where you saw these errors so I can look further?
As far as the rigging plate goes… opinions vary & I fully understand that many practitioners out there like using rigging plates. I also like using them, but I prefer to reserve them for places at the anchors. When rigging the rescue package end of rope systems, I tend to default to a “low-profile” philosophy & try to reduce the profile of the master attachment point, thus the bowline knot to act as the “yoke” or “MAP”. “Quicker” & “Safer” are subjective & relative terms to be left for interpretation by the individuals & teams that choose to employ certain rigging methods over others.
For me & my team, we would argue that it is quicker & safer to use the double long tail bowline rather than incorporating a rigging plate. For us, a rigging plate is just an extra piece of gear that we don’t need & just eats up additional real-estate in terms of height clearances. To quote a mentor of mine, “simplicity & complexity are not technique issues, rather they are training issues. What can be seemingly complex for some teams may be relatively simple for others.”