Kites….which one can break the world record?
Carlos Fandango – So the Peter Lynn Vapor at the moment seems to be the fastest race kite, and because of this the Vapor was also used to achieve the fastest kite buggy speed at over 84mph, but is this the fastest kite for a speed record…..In my opinion, there are many styles of kite that could possible hold the record. If you were to advise a team going for the speed record. Which kite would you tell the team to use, and instead of just saying a kite brand or name, give your reasons behind that kite choice
Ian Nudge Pearse – From what I was hearing the Elf could kick its arse
Andrew AutoBuddy Jones – I don’t think its just the kite tho isit… It’s being able to have the space to go downwind if needed to and not hit sand dunes etc.
Robin Cook – Am I right in thinking the vapour that took the speed record differed from the stock vapours? Ie tweaked and tuned.
- Ian Nudge Pearse – think its also right place right time as well.
Carlos Fandango – The space is unlimited….what kite will pull the buggy faster than any other kite?
I think RedSkyHorizon has the right idea….I quote “Thomas Mulligan – If it’s just one kite then I’ll take high wind sessions over low wind ones The 7m Genetrix Hydra has a wind range of 22mph-63mph on the water. On land and in a heavy bug this can be extended further still. I’ve already had 64.5mph from it just 2 weeks ago in 40-45mph winds with the depower trim at only half way. This kite currently holds the world speed sailing record. Bring on the truly nuclear winds”!
Robin Cook – Been tempted to follow Toms lead and acquire a small LEI for this winter.
- Carlos Fandango – I dont believe race kites are the answer to a speed record, they are designed to go around a course and travel up wind as fast as possible…that does not necessarily mean they are the fastest in a straight drag run.
- Alan Vidow – Personally, the 2/2.5/3m RM & the small combats. Has the record holder been trying to beat the record again & has he been trying other kites?
Bobby Muse – Robin, the Vapor that beat the current speed record was my kite that I purchased new from Coastal Wind Sports. No custom or tweaked anything. It was the same Orange/Blue that my other 2 Vapors are. Brian Holgate has that kite now and I’ve received a new one to replace it. Same Orange/Blue color as well.
Robin Cook – Cheers Bobby. Can’t remember who told me that.
Buggy Paul – only my opinion but I would pit my 10 year old Cquads in a straight line race against anything current.
- Mike Kenley – Consider all the factors, space, wind speed/direction, other weather conditions, surface (floor), buggy and how it is tuned, kite, pilot and a serious amount of brass if you know what I mean. I too think there are a number of kites that are capable of setting a new record however I personally think we are approaching the ceiling, physics and mortality will only allow so much. So I think it comes down to more preference than anything. My preference would be PKD
John Trainor – I think the Elf would take some beating on snow they got it winning most things and in the buggy it left the whole fleet in a race in France im told.
Maarten de Graauw – I hope there will be a Mumba and custom buggy at NABX2013……;)
- Laurent Calatayud – Pkd combat 2,4 or razor.2,5!
- Jerry Routh – I think a kite will need to be specifically designed for the task, something more rigid than a foil but more efficient than an lei.
Laurent Calatayud – you have to be at the right place, at the right moment, i think it is 70 per cent of lucky thing, don’t have to be a world champion to be fast on a straight line, only have bulls bollocks, and huge wind
Carlos Fandango – Brian Holgate is living proof of that one, freestyler with ulta confidence in his equipment….boom world record, and lets be honest here, he was only testing his set up…the next season should become very interesting
Matt Cook – I would choose a high aspect ratio kite. The drag (the force pulling backwards on the kite and slowing it down as it goes through the air) of the kite is made up of two components: one related to the physical size, shape and speed the kite is travelling through the air and the other is related to the fact that a wing doesn’t work as well towards the edges as the air spills over the end of the wing (due to the fact that the air above the wing is at lower pressure than that below the wing and the higher pressure wants to move towards the lower pressure). This effect can sometimes be seen on humid days when aircraft come into land and you get vorticies (swirling air vapour) forming just behind the wingtips. So, the total drag seen on the wing is:
Cd = Cds + Cdi
Cds – coefficient of drag due to wing properties
Cdi – coefficient of drag induced
The drag coefficient from the size and shape of the wing is incredibly like the lift coefficient (discussed here).
Cds = D * (A * .5 * r * V * V)
D – drag on the wing
A – Area of the wing
.5 – err… a half
r – air density
V – “apparent” speed the wing is travelling through the air.
D increases as the intrinsic lift of the wing goes up (as the wing is thicker – ever tried pushing a door open against the wind…). Whilst V increases as the wing goes faster.
The (even more boring) equation that determines the drag at the
wingtips (also known as induced drag) is:
Cdi = (Cl * Cl) / (pi * AR * e)
Cl – Coefficient of lift (different for different wings)
pi – 3.14159 – that number you did at skool
AR – Aspect ratio of the kite
e – a measure of the efficiency of the kite
So, the key to lowering this effect is getting the multiple AR * e as high as possible. e varies between 0 and 1 and is 1 for a perfect ellipse – so that’s why modern kites are shaped like they are. It also explains why the Spitfire (one of the most beautiful aircraft that ever flew) was so fast compared to the competitors at the time. So the only “real” variable you have to play with is the aspect ratio. Increasing it reduces the wingtip effect of drag.
Now, the interesting thing is that you can also reduce the drag by lowering the top of the equation (i.e. Cl * Cl) so there is a balance to play here. High aspect ratio kites that have a high amount of lift (err… anyone mention Blades…) will also have more induced drag from this equation. So you just can’t make the wing incredibly lifty otherwise the wingtip effect will slow the kite down reducing the lift (as the apparent lift you feel on the lines depends on how fast the kite is flying…)
So, race kite designers play with several variables. Getting a race kite to generate pull means getting it to move quickly as you can generate proportionately more power by moving quicker. BUT, drag is acting against you slowing you down so you want to minimise this by getting D low (make the wing thin) and reducing the effects at the end of the wing (by increasing aspect ratio).
KiteBuggy BagMan – An Rm in the right hands and Right Wind would retain record.
John Trainor – The fastest Kite I have ever used is the 2.4 combat but it may try to kill you like the old 1.8 century used to do
Matt Cook – pkd 3m brooza was producing lots of pull at 68mph i reckon its good for 90mph
Dirix Mano – I do not think it’s exact the kite. But more the right time in the right place. And the person who’s driving..
Brian Holgate – It all comes down to how fast the kite can go. You have to take into effect the aspect ratio as well as the bridles. For example the Vapor vs Reactor, the vapor wins due to its higher aspect. I think Gav Mulvay said the reactor starts to fall out of the window around 60mph. The Vapor continues to thrust towards the edge of the window allowing you to continue speeding up. That being said, the 3.2m vapor will not move as fast as the 2.7m and the 2.3m will move faster than the 2.3m, so you also have to take size into account. However you will always be effected by the bridles creating more drag. The question is will the drag on a 2.3m vapor be the same as a 7m LEI or a 9m twinskin? We will find out in March. At the end of the day its just a theory until its tested. What are your thoughts Gav Mulvay
Carlos Fandango – Then the earlier comment about Cquads comes into force, virtually no bridles = less drag
John Trainor – They don’t cut it any longer against a modern race kite. I only have the 1.4 & 2.2 now but they don’t compare with my current set of Century’s
- Carlos Fandango – Out of interest, do the latest race kites have wind speed ranges like RSH’s 7m Genetrix Hydra (wind range of 22mph-63mph)…like Tom mentioned that was on water, so in the buggy this figure will rise, and I assume will be much safer than a fixed bridle kite in winds over 50-60mph, but is it possible a kite like this can cut through the wind at 90mph
Robin Cook – Surely that figure would fall Carl.
Kite surfing requires more power than land so the wind ranges would drop??
For example 22mph would be the minimum wind to get up and planing on the water but rolling on a hard beach may find the kite working in 15mph of wind.
- Carlos Fandango – Well hopefully Thomas Mulligan will give us more info on this kite, I know he has done a lot of research before buying this kite
Phil Revill – Picking up on Jerry’s comments about a kite more rigid than a foil, but more efficient than an LEI, that points to closed cell? Two things, though, LEIs don’t need to be that efficient as you just fly a bigger size. A 5 or 6m LEI might do it, One of the small race LEIs perhaps. The UNO is hilariously fast. The other thing is the closed cell foil I’m thinking off has a massive amount of bridle, and therefore a lot of drag, and isn’t available in the smaller sizes you’d need. Thinking out side the box, maybe the kite youre looking for is a hybrid kite with a SLE but with the tube enclosed in a closed cell foil. Random.
- Mark Stiles – Speaking of SLE, I fly a Revolution Powerblast 2>4, back when they first made them they had the same power as a 4m foil. Not quite the same today but they are incredibly efficient for their size and you have almost 100% depower – I’ve flown mine in 30mph winds but as its a carbon fibre frame they are quite fragile once you land them. I’m surprised there isn’t a carbon fibre equivalent to an LEI.
- Jerry Routh – Picking up on Phil’s comment I think was FONE tried this many years ago it did not last long.
- Cliff Baker – On the whole LEIs are designed as “all-round” kites just that some may be better for wave riding, freestyle, hangtime or whatever these boys do on the water. Now kitesurf circuit racing is becoming ever more popular specialised high aspect racing LEIs are finally being developed and taken seriously.
- Thomas Mulligan – If downwind space is unlimited then in my humble opinion, any half decent race kite is capable of obtaining a new world record. And after-all, edging ever further downwind is basically having a depowering effect on a kite, with increasingly less surface area exposed to the wind. But unless you live in Vegas, then riding on short skinny beaches is the reality for most of us. Without any real option to edge downwind when the kite reaches it’s maximum then the only real option for me is depower. The hydra has probably the flattest profile of all LEI’s and therefore huge amounts of depower, but whether it will be any more advantageous than a race kite at Ivanpah is uncertain. I guess there’s only one way to find out.
Brian Holgate – @ cliff PL makes a high aspect LEI called the Fury. That is going to be my go to kite! the 7m will be wicked fast I imagine. @ Thomas you can always come visit. We will welcome you with open arms and get you all set up. I suggest come ready to camp though. There is nothing like hanging out on the playa at night. And if that isn’t enough to satisfy you. We can buggy in the morning and drive 45 minutes to Mojave. Sorry for the tangent Carlos, it was necessary. 😉
- Thomas Mulligan – Thanks Brian. Just camping out under the stars at Ivanpah is enough to entice me over + a quick go in the PL speed. 🙂 Hope to see you at NABX 13.
Carlos Fandango – Thomas Mulligan do you agree with Robin Cooks theory that Hyda with added weight of a buggy ect the wind range would reduce….I do kind of understand his point
Andy Read – Great explanation Matt, and from an aeronautical POV I think it demonstrates that the current manufacturers of either FBs or LEIs are pretty close to an optimal shape in terms of speed ie. high AR, thin sections etc. So now we have to address efficiencies – what you might call ‘marginal gains’ – this might involve thinning down bridle set ups in some way or adding winglets to reduce induced drag.
However, I think the largest step forward in increasing the efficiency of a wing shape and profile would be to stiffen it somehow. A semi-rigid kite, as others have mentioned, would ensure it’s optimal shape is maintained throughout the stresses placed on a wing in a high speed run. So, to lay my cards on the table, I would love to be able to develop a rigid or semi-rigid composite wing with all the speed mods that are currently available in modern aircraft. Is this still a kite? If it’s still on lines, then I guess so. All we’re talking about is wind power, are we not? The increased rigidity would also enable us to reduce the bridling requirements and therefore reduce bridle drag.
I won’t have one ready for Camberstone this weekend(!) but I reckon there’s something in it….
Alan Vidow – Personally I’d like to see how Stephan van Bommel would get on with the speed buggy (could that be improved?) with the small race kites, as he isn’t far off the previous record but on a race spec buggy.
Carlos Fandango – Stephan would never fit in the speed buggy, I think he is too tall, could be wrong there…..there is also I believe a reason the speed buggy speed is so close to Arjens speed, and that is because, the speed buggy is no where near its full potential speed yet, where as a buggy pilot sat bolt upright is, in the shear physics of it, near its maximum speed…..Arjen, is still the record holder for the standard buggy configuration…..the speed buggy will in my opinion make the gap much wider than it is now, and then we will have to discuss buggy class categories
- Andy Read, I love how you are thinking, and it will be people like you who grab the bull by the horns and take some chances to discover new ways forward just as Craig Hanson, Peter Lynn and , Gav did with the speed buggy….go for it.
- Carlos Fandango – Could LEIs go that fast through the air……I think they possibly could
- Buggy Paul – No but put a spar in one and it would
- Thomas Mulligan – @Carlos Fandandgo, with regards to Robin’s theory that the Hydra with added weight of a buggy ect the wind range would reduce. I can understand his point of view too and yes I guess he is right, but flying on water and flying on land are completely different. You would quite happily static fly the Hydra in 60mph winds on the beach, fly it from one side of the window to the other and not even move from the spot or get dragged downwind.
- You couldn’t do that on water because if you were to stop you’d sink. Climb into a heavy bug and you can loop the kite in those winds.
- I’ve flown the 7m Crossbow in 58 gusting 72mph on-shore winds and the 7m Crossbow is supposed top out at a little over 40mph on the water. Just the mere fact of being on land increases the wind range, whether you’re in a flexi bug or whatever.
Ken Shaw – It’s been done the best way already, just not in a kite buggy. The fastest thing is going to be a symmetrical helicopter rotor foil profile in carbon with a control system that allows very fine pitch adjustment. It’s gonna be twitchy, it’s gonna be evil to fly and it’s gonna take miles to get it up to speed but, it’s gonna be very, very fast.
Bobby Muse – I like the idea of an SLE with a carbon spar instead of the larger diameter bladder. I also like the idea of the fixed wing like the newest high performance sailboats (and Greenbird) use.
- Mark Stiles – My Revolution Supersonic can rip through the air at 70mph, its just very small so there isn’t much pull unless you kite loop it constantly – now if you scaled that up a few meters 😉
Carlos Fandango – FYI, the fastest recorded speed of a kite is over 120 mph. (193 km/h).
Mark Stiles – Ah right interesting, will look that up be interesting to see what design it was.
Brian Holgate – It would be interesting to try this on a revoulution kite.
Ken Shaw – I’m afraid the Rev 3 wraps wouldn’t hold up. I’ve come very close to snapping my speed series Blast in half in 35mph winds. It would have to be beefy but I think you’ve got something there, Brian.
Andy Read – Hey Carlos Fandango, sorry I missed your post last week. Thanks for the encouragement. I’ve been drawing up ideas for a while now but it’s still very conceptual – which just means it’s still in my head! But, hey, it has to start somewhere. 😉
- Mark Stiles – Ken, I’ve flown my powerblast in 30mph winds without a problem – the main spars are much beefier than the speed series. My supersonic pulls well in higher winds only time I’ve broken a main spar was from contact with the ground – in high winds the ferrules will give way before the spars – they are the weakest part of the revs.
- Ronan Allain – LINK
French championship winner kite
100% french product, design and manufacture.
Same price as Vapor but made in Europe…
- Cresus Archipelago – tres expensive mon ami!
- Ronan Allain – Yes it is… Vapor is quite expensive too! However, mostly depends on the pilot.
- Arend Geerlings – Vapor?? What is that?? The dutch round one championchips…..first Z3, Second Z3, Third Spirit, Four Spirt…where is the Vapor?
- Bobby Muse – round 1 of 1 race? I think Pops is referring to results over the last 2-3 years at any event you want to look at.
- Alan Vidow – Pops is referring to the speed record.
- Arend Geerlings – More kites can do the job…..but can the Pilot? A F16 fighter plane can do more things than the pilot can handle. I think the limit is the pilot not the kite.
John Jones – I agree with Arend Geerlings, its all down to the pilot having the balls to hold a big kite in a higher wind and be able to push that bit harder, oh and its not me 😀
- Carlos Fandango – Yes but if we have a pilot with the hooojest balls, in the hooojest dry lake bed with with a constant wind of say 60mph…..what kite will sit far enough forward in the window to pull you faster than any other kite….thats what this question is about…..the fastest kite
- Matt Cook – you dont all ways need a race kite to go fast thoug
- Carlos Fandango – my sentiments exactly
- Monty Oriet – The kite. It has two have the ability to go through air. Less drag,That is way the PL Vaper at time works best. And pilot, Thare are two at that have done that.
- Carlos Fandango – yes but like previous comments….the bridling adds drag…so perhaps not the best option
- Ken Shaw – The Crossfire II gets further in front of the wind than anything I’ve seen but it’s not the right answer for high speed as high winds are always gusty and the Crossfire is VERY reactive to gusts, too reactive. Although, we’ve all seen Chris Krug cutting up wind on an ice covered lake with skis at an seemingly impossible angle… a properly tuned mattress in the right hands almost fits the model of a high aspect, neutral profile wing where AOA is the driving factor rather than profile.
- Al Noblet – There was an old sled kite called a wingine speed, built and works just like an arc but with a much thinner wing section, i think these kites have a place in speed attempts with a range of depower, zero or almost zero bridal and super stable …..its just that you dont get as much pull per square meter as a foil so need more rag in the sky, so their goes the advantage you had with no bridal…..i think the kits are gonna end up specilist bits of record braking kit instead of productionbsed planforms, everything to do with going fast ends up specialist, look at the boards for kitesurfing attempts…its a bit trikier with a kite, i think they wil start becoming more of a solid wing on strings than a fabric foil, the kina thing you have to start flying from the back of a truck just to get the apparent started!!!!
- Arend Geerlings – C-quad.
- Andy Read – If you just want to know the fastest production kite then you have to take the main variable out of the equation ie. the pilot.
So then you get one pilot to fly a variety of race kites in the same conditions over the same course and get an average of runs to see which is the fastest.
However, don’t forget the origin of this post which is about ‘advising a team for a speed record’. Even the best race kites are a compromise of cutting upwind, reaching and handling. An out and out speed machine will be different again and will be one developed specifically for the job.
I agree with Al Noblet that it may well need to be of a more solid construction and which would be a b!tch to get going and stop – I like the idea of a tow start, though :-]
Marc ten Brink – Vapor is simply the fastest
- Mike Caelers – Rhombus Firebee 😛
Chip Brown – I think a Rev design with the right setup would be the best possible kite out of all the “proven” kite designs. (meaning kite styles that exist today and are known to work.) The reason is wind resistance which has been discussed and controllability which no one has mentioned yet. The correct Rev does not currently exist however.
To qualify my statement; Some of you may know me from NABX as the crazy guy in the leather buggy who flys nothing but Rev’s, so yes I’m biased, but I’ve put a lot of miles on a Rev the last few years. I have a full set of foils, but I rarely fly them, I enjoy the challange of flying a rev, you feel far more connected to the kite than any other kite I’ve ever flown. Part of this is the nature of how you control a Rev, by adjusting the independent angle of attack for each half of the wing surface by rotating your wrist.
A Rev has a true 4 points of control, full power on all four lines at all times. Apart from making it harder to fly, it allows micro adjustment of the wing at full speed. Tiny adjustments of wrist angle speed and slow the kite in a way not possible with a foil. When trying to get the most out of a rev, you can balance the forward speed by flattening the kite (fast but less pull) or increase the amount of lift by lowering the trailing edge (pulls a lot but slows the kite), all without sacrificing the aerodynamics of the kite. And you can do this independent for both halfs of the kite.
One major limitation for Revs however is the ability to harness them. Without a harness you cannot hold enough power with your bare hands. The Revs controllability is its weakness here, unlike a foil there is no fixed point to anchor the harness strop. I solved this problem with a new harness design that worked beautifully last year at NABX.
I flew my Power Blast 2-4 in 40+ mph winds and really pushed the kite. I also flew the 4-8 and 2-4 back to back in 30 mph winds. The 2-4 was faster because of the higher profile, but it’s a bit to small at only 2 meters to get the job done. But on a unstable buggy with 12mm bearings that wouldn’t stop seising I was able to get 56mph with a 2 meter kite in 30-40 mph winds.
To go really fast I’d need a larger higher profile Rev, and a better buggy.
The ridged spars are a week point, but the carbon fiber wrapped graphite of the rev spars are increadably strong. And they can make them stronger by adding more wraps of carbon fiber, at the cost of weight.
As Mark mentioned, the plastic furrels are the weakest link. I pushed my Revs hard last year, and I broke spares, but only the small uprights, and every single one happened after breaking a furrel. When a furrel breaks the compression on the rod is released suddenly and violently, and about 1/3 of the time the spar would shatter. I broke about 9 furrels last year, and about 3 rods.
The leading edge spar is incredibly strong, as long as you don’t bash it into the ground, or after breaking a furrel on the far end of the lake bed have a rogue gust catch the kite and wrap it around your head. 😉
For next year at NABX I’m working on machining aluminum furrels to hopefully solve that issue at least. And dreaming of a larger Rev