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Lifeguard trebuchet

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  (+19, -2)(+19, -2)
(+19, -2)
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As usual, the lifeguard sits in one of those tall chair things, with binoculars.

On spying a swimmer in difficulties, they record the range and bearing infomation on a keypad, then descend from their perch using a fireman's pole.

At ground level, they jump into the trebuchet sling, attach the equipment bag clip to their belt, and press the "launch" button.

The trebuchet automatically swivels onto the correct bearing, and propells the lifeguard, pus a package of equipment on a line, on a ballistic trajectory toward the swimmer, said trajectory being adjusted so that neither the lifeguard, nor any of the equipment, actually lands on top of the swimmer (it is assumed that such an even would only make things worse).

While in the air, the lifeguard assumes a graceful diving position, closes their eyes, and waits.

On surfacing after imapct, they swim to the rescuee and duly rescue them.

8th of 7, Jan 25 2011

Projectile Motion 2.02 http://phet.colorad...tile-motion_en.html
In case anyone needs a calculator... Be sure to set the projectile to 'adult human.' [Alx_xlA, Jan 27 2011]

[link]






       Hmm. Just have the lifeguard sit in the sling, already elevated to the correct height. Sure you'll lose a little bit of throw starting from a couple meters up, but that can be compensated with arm length and aditional counterweight.
MechE, Jan 25 2011
  

       Two words.   

       Barnes.   

       Wallace.
MaxwellBuchanan, Jan 25 2011
  

       Wallis. (If you’re referring to he of the Vickers Wellington geodesic airframe, that is).
Ian Tindale, Jan 25 2011
  

       I was actually referring to the famous Isle of Wight lifeguarding twin brothers, Barnes and Wallace Speng, who first developed this system in the 1950s. The Needles can be terribly unforgiving at those sorts of velocities.
MaxwellBuchanan, Jan 25 2011
  

       Meh, the bouncing bomb depends on a fairly flat trajectory. Trebuchet's can be designed to launch in a high arc instead.
MechE, Jan 25 2011
  

       [MB] if you know of a lifeguard who's prepared to be spun up to 500 RPM and then be dropped from a Lancaster at 232 knots and 60 feet altitude, please let us know.
8th of 7, Jan 25 2011
  

       Hey, I'd go.
MaxwellBuchanan, Jan 25 2011
  

       Trebuchet is actually an attractive choice for launching lifesaving equipment, as its simplicity should make it reliable with little maintenance.   

       There would be a minimum depth of water at which this could be used safely. That could be reduced by the use of either drogue parachutes or (more reliable I think) a rapidly- deploying balloon-float. For the latter, a modified automobile airbag should do the trick. It will need some sort of quick-release, lest the lifeguard be trapped underneath -- but the balloon could then serve as a flotation device to assist with the rescue.   

       The airbag/balloon would also offer protection in the event the trebuchet dropped the lifeguard directly onto the victim. (//such an even would only make things worse// On the plus side, it would greatly enhance the whole affair from the spectators' point of view.)
mouseposture, Jan 25 2011
  

       Love it. Bungie launch would be good too.   

       Heh, skipping stone lifeguard, if the launch angle was shallow.
Ling, Jan 26 2011
  

       Wow [+] this is an absolute necessity!!!
xandram, Jan 26 2011
  

       Splendid idea.

I would also like to champion the concept of the lifeguards' hut being converted into some sort of Baba Yaga arrangement, with huge telescopic legs, so that the whole building can go wading out to the rescue. Although not as simple to maintain as a trebuchet, this has the additional benefit of being able to transport medical equipment to the scene rather than having to drag some bedraggled swimmer back to the beach before they can recieve treatment.
DrBob, Jan 26 2011
  

       Great idea, but the Baba Yaga version of Pamela Anderson would have to waste time running up and down the beach trying to catch the hut before they could even start thinking about rescuing the incompetent tourist.
pocmloc, Jan 26 2011
  

       Why not launch them along with their jet ski (with wings) for faster retrieval.   

       plus I think you would have to do the math of ballistic trajectories, I don't think most life guards are trained to survive 30m falls.
metarinka, Jan 27 2011
  

       // life guards are trained to survive 30m falls //   

       Well, that wasn't in the specification. If you wanted the lifeguard to actually survive the journey, that will take more work.   

       Calcualting a trajectory based on a known mass and wind speed is pretty straightforward, even for something as unaerodynamic as a lifeguard.
8th of 7, Jan 27 2011
  

       It would require more infrastructure, but you'd probably get a more enthusiastic response with a zip line system.
normzone, Jan 27 2011
  

       Would you care to elaborate ?   

       Are you suggesting pehaps an unfeasably long, thin, completely rigid rod (of necessity made from Unobtanium alloy) with a roller running down it, and a float to support the far end, or do you suggest launching a full-size powerboat traling a cable and then using the boat to maitain the tension in the cable (to a very tall tower) while the lifeguard slides down it ?   

       Having considered this, [mouseposture]'s idea of launching the lifeguard along with a single-use inflatable dinghy, filled by a pyrotechnic gas generator, that inflates in the air to slow the lifeguard's descent, and acts as a rescue platform upon landing, is really good.
8th of 7, Jan 27 2011
  

       //Calcualting a trajectory [...] is pretty straightforward, even for [...] a lifeguard//   

       But if you don't bind and gag him first, his struggling will be a distraction.
lurch, Jan 27 2011
  

       Oh, definitely a series of bouys with an ever-fluctuating set of flexible steel cables would not scare off potential lifeguards as much as the projectile approach.   

       Let's take it further. Equip great white sharks with "no-bite" devices, and periodically shoot large quantities of chum from a cannon into the offshore swim zone.   

       When a struggling swimmer waves for help (this is why you don't wave at people while you're in the water) the guard simply fires a cannon of chum, the shark shows up and attempts to eat the swimmer.   

       The breakaway Swimmer-Saver part of the no-bite device inflates and saves the swimmer that the shark attempted to feed on, and the lifeguard fires the following side of beef as a reward.   

       Okay, maybe I need a vacation. At the beach.
normzone, Jan 27 2011
  

       [+], however safety would be increased if the lifeguard were to scream loudly and wave his/her arms and legs while airborne, to ensure that the people below were aware that he/she was flying through the air above them and could land anywhere.
AntiQuark, Jan 27 2011
  

       I'm guessing that a dead person has some buoyancy, until their lungs fill with water, so even if the lifeguard does not survive the experience, they will have done something to help.
not_morrison_rm, Jan 29 2011
  

       Apparently it's the thought that counts ...
8th of 7, Jan 29 2011
  

       This made me laugh. +
blissmiss, Jan 29 2011
  

       I was thinking, as an additional measure, all the swimmers get a 1m piece of string. Everyone on the beach gets something like a paintball gun, but it fires different coloured polystyrene spheres, with a hole through them.   

       Then, at the cry for help, the beach people fire the spheres towards the drownee, who can then collect the spheres, thread them on the piece of string and make themselves a life belt, until the lifeguard gets there. Prizes could be given for closest shot to the drownee, and for the drownee, points for arranging the spheres in colour combinations pleasing to the eye.   

       All in all, turning what could be a most stressful event into something more lighthearted..
not_morrison_rm, Jan 29 2011
  

       As demonstrated by Ms. Anderson, some calculation for differences in frontal areas must be taken into account, as some lifeguards are more aerodynamic than others. Mr. Hasselhoff's hair, for instance, makes an excellent leading edge.
RayfordSteele, Jan 30 2011
  
      
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