A few weeks ago Jeff Elkins of Flyboardpcb.com sent me an idea for an article asking the question ‘How high is too high?’
Looking at the evolution of the technology associated with Flyboarding, dual impellers, powerful pwc’s, longer hoses the question has become a legit one… Flyboard Heights – how high is too high? 75ft, 90ft, 100ft?
I reached out to a number of my Flyboard industry contacts and requested their thoughts on this subject. It was very interesting to see how each response touched on a different aspect of this question. The responses below are exactly as I received them… if you agree, disagree or have something to add please do so in the comments.
Up first Bobby Vance of Aquafly
It’s not so much a question of how high should you go, it’s more a question of how high can you go?
So when considering Flyboard Heights – ‘How High is Too High’ or how long should a hose be, we are completely limited by the power of the PWC that we are using. Remember, a PWC is designed to scoot across the top of the water, not pump water up a hose. What it truly comes down to is the pure physics of the matter; the weight of the water inside the hose and the friction loss associated with moving that water through the hose.
First lets look at the weight of the water. In order to accurately calculate the volume of water in the hose, the following formula will be used:
R=Radius of the hose in inches which is 2.125”
H=Height (or length) of the hose in inches which is 720” (60’)
V=3.1416 x 4.515625 x 720 = 10,214.127 cubic inches
Water weighs .036127 pounds per cubic inch
10,214.127 x .036127 = 369 pounds
So the standard 60’ hose weighs 369 pounds when full, add a 200 pound rider, an additional 70 pounds for the weight of the hose and Flyboard® and you’ve got a total weight of about 639 pounds. Then calculate the pressure loss due to friction as the water moves through the hose and you can see how the PWC’s ability to lift is going to be limited. Now add another 20 feet of hose and your weight increases by another 123 pounds. This would now be the equivalent of flying a 325 pound person.
With this said, I don’t think it is possible to exceed 50 ft or so even with a longer hose and the most powerful stock PWC with a double impeller. And if it could be exceeded, I would not want to elevate more than 50 ft nor would I want to fly someone higher than that if I was on the PWC.
Now let’s assume the technology can take us to these extreme heights… what if we fall?
Pro Flyboarder Trey Andrews, finished 10th in the 2013 Flyboard World Cup, looked at the physics of a fall from these new heights. Here’s what Trey had to say:
Great question and I believe this is something we should all think about. While some will disagree with me the current height is plenty, but my reasoning is simple. If something catastrophic happens (engine blows, pumps seize, adapter plate breaks), and it will at some point, you want to be able to survive the fall. With the current out of water hose length that puts you just under a 50ft (16 m) fall, it’s very survivable but there could be injuries. Say you step that up to 75ft (25 m) or 100ft (33 m) and you will have broken bones and internal injuries.
To me what makes the Flyboard fun is the speed of acceleration and not just the height. The double impeller helps tremendously with that.
Just to make this a little more understandable let’s do some quick math about how fast you will be falling.
I used a constant weight (mass) @ 75kg (165lbs) and looked at the mph at impact at different heights
50ft (16 m)- 39mph (63kph)
75ft (25 m)- 49mph (80kph)
100ft (33 m)- 56mph (91kph)
There calculations are NOT 100% accurate as there are a bunch of other factors that come into play but this I think gives the best reason why we should keep the height where it is!
Heck looking at that now I’m not sure how I did not get hurt when my pump seized at full throttle!
If these new heights became achievable how would that relate to water depth?
I used this at a recent meeting with maritime in one of our banned states for operation. We have also decided against selling the dual impeller system at this stage due to liability concerns. Below is an article on Wikipedia outlining the issues with tower diving and heights. It has been the best information I have found to date which clearly outlines the risks involved. Taking the Flyboard to these new extreme heights is safe when used by a safe and experienced operator; but what if the ski has an issue and suddenly no power? A ski operator is thrown from the ski? The ski operator releases the throttle? Or a rope gets caught on the impeller shaft? Whilst I will continue to use this new equipment to attain more power and new heights, I am always wondering what if?
Points on pool depths as it relates to safety (TOWER DIVING):
- most competition pools are 5m deep for 10 m platform and 4m deep for 5m platform or 3m springboard. These are currently the FINA recommended minimum depths. Some are deeper, e.g. 6m for the diving pit at Sheffield, England.
- diving from 10 m platform and maintaining a downward streamlined position results in gliding to a stop at about 4.5 – 5m.
- high standard competition divers rarely go more than about 2.5m below the surface, as they roll in the direction of the dive’s rotation. This is a technique to produce a clean entry.
- attempting to scoop the trajectory underwater against the rotation is extremely inadvisable as it can cause serious back injuries.
- hitting the water flat from 10 m brings the diver to rest in about 1 ft. The extreme deceleration causes severe bruising both internal and external, strains to connective tissue securing the organs and possible minor hemorrhaging of lungs and other tissue. This is very painful and distressing, but not life-threatening.
Flyboarding, recreational activity and professional sport…
Chris De Santo of Flyboard Cairns clearly differentiated how this question relates to the public and the pros.
Safety is always a big concern for us at Flyboard Cairns. We have some strict limits for the people we fly generally limiting them to 2m, 4m and 6ms based on their experience and past history with us (repeat customers and annual pass holders). I think it’s very important for us as operators and as the stewards of flyboarding to carefully watch and maintain limits on new flyers (those without a large amount of experience with the sport). Without carefully controlling them within the boundaries of safe operation we could put ourselves at risk to serious injuries like JetLev has and continues to experience.
Having said that, with pro riders I think the future is definitely bright! Our sport is extremely visual and being able to push limits and boundaries (heights) adds to the wow factor that surrounds the sport. I would be pretty stoked to get up to 30 meters (90 feet) but I think I would definitely be stopping there! The risk reward factor will sort itself out correctly, but I fear the higher we push into the sky the more depth and radius we will need in our flight areas. This will most likely sort itself out via safety legislation. We should be looking to create these standards ourselves though so that it’s a regulation we agree with and not something handed down to us.
BIG THANKS to Bobby, Trey, Peter and Chris for sharing their initial thoughts on this important subject.
As our sport evolves this question will continue to get asked and debated. Sports that are mature have all gone through this balancing act of safety versus innovation (add a dash of reckless stupidity) and you realize it never fully resolves itself. The technology will continue to evolve. Right now we use a PWC to propel the water up the hose, which as Bobby pointed out these machines were not built with this purpose in mind, but what if a purpose built machine replaces PWC’s specifically for flyboarding and they have the incredible power needed to manage the increasing weight? If it’s possible to fly 100ft in the air someone is going to do it… should they… well that’s the debate.
The Flyboard community knows that safety is and must continue to be the most important aspect of our industry. Every attempt is made to make Flyboarding a fun, safe experience for everyone. Authorized dealers and certified instructors ensure that the public pass the necessary safety courses prior to owning the equipment and deliver safe experiences during lessons. This attention to safety runs parallel with the Professional Flyboarders around the world taking their expertise to new heights and demanding more from the technology associated with the sport. Greater risks will be taken, tragedies may occur but I honestly don’t know how a sport finds its ‘edge’ without flying into uncharted territory. Cars crash… they continue to race faster. Cliff Divers plunge from heights once unthinkable and now Flyboaders… well they’ve just begun working to maximize the current technology but some are already dreaming of where they might eventually take their sport.
We value your opinion… so please take the time and contribute in the comments.