 Poster: A snowHead
|
What skis are you guy on that are claiming 60/70mph? You are going to find it pretty hard to get to that kind of speed without being on something pretty stiff and long.
I clock over 60mph in a few SG races it never felt that fast, no were near my max but that was because I was on a pair of 208 SG boards and I was in a Catsuit.
|
|
|
|
|
|
Obviously A snowHead isn't a real person
Obviously A snowHead isn't a real person
|
My new male ego massager phone app measured mine at 18 inches ... oh, is that the wrong measurement ... sorry wrong thread ... or is it the right one! 
|
|
|
|
|
|
Well, the person's real but it's just a made up name, see?
Well, the person's real but it's just a made up name, see?
|
| Quote: |
That just sounds irresponsible to me but perhaps I am just more/over protective of my children. I would not encourage them to ski at speed; technique and elegance are far more admirable goals.
|
Actually it is fairly easy to do that speed if you are a little boy. I wouldn't say though that speed, technique and elegance are mutally exclusive.
My son skis with a gps as he skis in a club and we like to know where he has gone and he can talk us through the day. He skied in a slalom race on saturday and got a speed at about 55 km/hr. This is somewhat slower than his free skiing speeds, and it looked farily slow as a spectator.
There is a big difference between sustained speed and spiking a bit of speed.
|
|
|
|
|
|
You need to Login to know who's really who.
You need to Login to know who's really who.
|
|
89 kmh in les arcs - from a couple of seasons ago, measured on a garmin foretrex. Wasn't a piste I knew that well, so I backed off a bit towards then end, would quite fancy another go on something like Bellette...
|
|
|
|
|
|
Anyway, snowHeads is much more fun if you do.
Anyway, snowHeads is much more fun if you do.
|
| Dec wrote: |
What skis are you guy on that are claiming 60/70mph? You are going to find it pretty hard to get to that kind of speed without being on something pretty stiff and long.
I clock over 60mph in a few SG races it never felt that fast, no were near my max but that was because I was on a pair of 208 SG boards and I was in a Catsuit. |
Mine might have been a typo, it was either 57 or 67 but i can't remember which now. And as said, was on a mates phone so not entirely convinced by its accuracy. Did it on 185cm Nordica Supercharger Enforcers. The name sounds fast at least.
Edit: checked it with my friend, apparently it was indeed 67. Whether true or not, I'm quite happy to beleive I can go nearly 70mph on a blue run.
|
|
|
|
|
|
You'll need to Register first of course.
You'll need to Register first of course.
|
briand6868,
You beat me by 0.1 kph.
At 6 stone he must have had fast skis...........i'll get you next time.............!
Going fast and staight down is pure fun !!! 
|
|
|
|
|
|
|
|
|
el nombre, I've got those skis.. Love 'em to bits.
|
|
|
|
|
|
|
|
| rob@rar wrote: |
| I like turning. Going fast in a straight line seems to be a waste of a good slope. |
+1, nothing better than carving a turn at speed and feeling the ski push back against your foot.
|
|
|
|
|
|
You'll get to see more forums and be part of the best ski club on the net.
You'll get to see more forums and be part of the best ski club on the net.
|
| Quote: |
My new male ego massager phone app measured mine at 18 inches ... oh, is that the wrong measurement ... sorry wrong thread ... or is it the right one!
|
roga, The best post in this thread, 
|
|
|
|
|
|
|
|
freeheelskier, 
|
|
|
|
|
|
snowHeads are a friendly bunch.
snowHeads are a friendly bunch.
|
Hi All,
I ran one of those free apps on my iPhone last year and it clocked me doing 140mph. Now I don’t know about you but I wouldn’t travel that fast if I fell off a cliff !!. In Super Chatel last year I clocked 72kph (45mph) through the speed gun and thought it was nearer 90!!. In our group three of us were carrying GTrek GPS data loggers and decided to ski down to Linger (not sure if that’s spelt right) I clocked 64mph and I was the slowest. Our chalet host came past me like I was standing still and he clocked 71mph.
|
|
|
|
|
|
And love to help out and answer questions and of course, read each other's snow reports.
And love to help out and answer questions and of course, read each other's snow reports.
|
|
My Garmin GPS said I did 420kph while hiking once. I think it lost signal then assumed I travelled instantly between the point where I lost it and the point I regained it or something. Since then I haven't really trusted the GPS speed measurements...
|
|
|
|
|
|
|
|
|
101 kph don't know if correct but I did 80 kph in a pretty short speed trap at Lech so I suspect it is. Didn't feel ludicrously fast and it was on pocket rockets.
|
|
|
|
|
|
You know it makes sense.
|
|
I use a GTrek when I'm skiing and last year I also used an iPhone App as a comparison, it clocked me doing 148mph which is something I would not be capable off even if I fell off a cliff. My fastest speed recorded is 64mph a colleague who also had a GTrek came passed me and clocked 68mph. Life is so unfair.
|
|
|
|
|
|
Otherwise you'll just go on seeing the one name:
Otherwise you'll just go on seeing the one name:
|
| nutwood wrote: |
Hi All,
I ran one of those free apps on my iPhone last year and it clocked me doing 140mph. Now I don’t know about you but I wouldn’t travel that fast if I fell off a cliff !!. In Super Chatel last year I clocked 72kph (45mph) through the speed gun and thought it was nearer 90!!. In our group three of us were carrying GTrek GPS data loggers and decided to ski down to Linger (not sure if that’s spelt right) I clocked 64mph and I was the slowest. Our chalet host came past me like I was standing still and he clocked 71mph. |
| Quote: |
I use a GTrek when I'm skiing and last year I also used an iPhone App as a comparison, it clocked me doing 148mph which is something I would not be capable off even if I fell off a cliff. My fastest speed recorded is 64mph a colleague who also had a GTrek came passed me and clocked 68mph. Life is so unfair. |
If you are going to post spam, please try to be consistent.
|
|
|
|
|
|
Poster: A snowHead
|
The whole top speed thing is a bit weird, if you're carving nice tracks down a piste and clock some fast speeds then great but hurling yourself down a run in a straight line whilst tucking, in my opinion, isn't skiing. That's just falling quickly, no skill involved only stupidity.
I do use skitracks app to track my days, the features and analysis are interesting, as is the top speed but it's not the be all and end all.
|
|
|
|
|
|
Obviously A snowHead isn't a real person
Obviously A snowHead isn't a real person
|
|
Anything over 50MPH after tucking for less than 500 mtrs should be viewed with a pinch of salt, and if you could pull up at that speed without a huge scrub off or rapid changes of direction or crashing speak for itself.
|
|
|
|
|
|
Well, the person's real but it's just a made up name, see?
Well, the person's real but it's just a made up name, see?
|
| Cynic wrote: |
| Anything over 50MPH after tucking for less than 500 mtrs should be viewed with a pinch of salt, and if you could pull up at that speed without a huge scrub off or rapid changes of direction or crashing speak for itself. |
Really? How can you possibly say that without knowing every single bit of Piste out there? I hit 56mhp in the 3V a few weeks ago, and it felt very fast, i didnt tuck for 500m, i hardly even tucked at all if im honest.
|
|
|
|
|
|
You need to Login to know who's really who.
You need to Login to know who's really who.
|
My mates did 105kmh on Trolles down into Tignes Le Lac.
I wasn't so brave.
|
|
|
|
|
|
Anyway, snowHeads is much more fun if you do.
Anyway, snowHeads is much more fun if you do.
|
Last week the local ski school got their speed trap out (optical system with print out so no GPS silliness) and let people run through it for a nominal fee. Green slope, about 1 inch of powder, standing start from c100m up hill so not somewhere to expect mega speeds.
My 9 year old son's best pass was 34mph. The kids in race school went through at 45mph. The best adult was about the same speed.
It didn't actually look that fast from where I was standing and my son said we go much faster on the run outs from most red pistes. I could easily imagine 45+mph without trying too hard. Much more might be a little dangerous though given the stopping distance required!
|
|
|
|
|
|
You'll need to Register first of course.
You'll need to Register first of course.
|
I don't believe these GPS apps or gizmos are accurate for measuring skiing speeds.
In the 3 Valleys recently, I had the 3 Vallées iPhone app logging my top speed, as well as a GTrek II GPS Trip Recorder, configured for skiing and set to log once per second (but which probably should have been set to 5hz instead). I was skiing as I normally ski and not trying to deliberately go as fast as possible; at no point was I in a tuck or skiing in a straight line.
The 3 Vallées iPhone app recorded a top speed of 85.3 km/h (53 mph).
The GTrek II recorded a top speed of 89.3 km/h (55.5 mph) with the PC software's Filtered Data function switched on and 102.8 km/h (63.9 mph) with it switched off. I don't know what the Filtered Data function actually does but the help file says, "it is used to filter out positional noise on the recorded data" for the altitude and speed displays.
The man who markets and sells the GTrek II told me that occasionally there are spurious speed spikes, usually caused by signal reflections off mountainsides. He asked to see a copy of my data file and after kindly examining it, he wrote back to say that I skied above 50 mph on many occasions during the week.
During the women's downhill race in Sochi, shown on Ski Sunday on 19 February, Lindsay Vonn was measured at 112 km/h (70 mph) and 80.8 km/h (50 mph), on >210 cm skis, wearing a race suit.
So are GPS gizmos useless for measuring skiing velocity accurately, or were the temperatures that week too low for the technology to function properly? It was down to -20 °C sometimes, well below the minimum operating temperature for an iPhone, which is 0 °C. The GTrek II has a minimum operating temperature of -10 °C.
I don't think it is possible to go over 50 mph on my new 163 cm HEAD i.Supershape Speed skis, even in short bursts on completely empty pistes. I think a lot of people are deluding themselves if they think they are skiing at downhill course racing speeds on recreational skis, wearing recreational ski clothing. Am I wrong?
|
|
|
|
|
|
|
|
|
Easily over 1000mph (prolly closer to mach 2.0 tbh). Both on skis, and on MTB (uphill).
|
|
|
|
|
|
|
|
| Quote: |
The GTrek II recorded a top speed of 89.3 km/h (55.5 mph) with the PC software's Filtered Data function switched on and 102.8 km/h (63.9 mph) with it switched off. I don't know what the Filtered Data function actually does but the help file says, "it is used to filter out positional noise on the recorded data" for the altitude and speed displays.
|
Walter-Spitty, basically the GPS is continuously recording positions regularly and uses that to calculate your speed as velocity is merely the rate of change of position. The filtering smooths out erroneous recorded positions in the data. Imagine skiing down the hill and the GPS is polling it's location every second. Every second you are travelling 10m so your speed is 10 m/s. An error causes the device to record you position for one poll as being 20m different from the previous position, suddenly for that one instant it thinks you are travelling at 20 m/s. A naive GPS or user might think they did hit 20 m/s but in actuality they never exceeded 10 m/s. To correct for these errors you need to do some smoothing or apply some filtering criteria. If you're measuring top speed by the max speed the GPS gives you and you or the device aren't doing that then you are likely to have an overly high estimate due to these spikes. Errors can be introduced by losing signal momentarily or by things like signal reflection from mountains or nearby buildings.
|
|
|
|
|
|
You'll get to see more forums and be part of the best ski club on the net.
You'll get to see more forums and be part of the best ski club on the net.
|
Just to add that polling rates are generally higher and errors generally smaller so the above numbers were plucked from thin air in order to be simple.
If you think about the accuracy of GPS it has quite a high margin for error in measuring skiing velocities even without imprecision caused by signal errors.
|
|
|
|
|
|
|
|
meh, thanks, I guessed that was what the software filtering was doing. Good to see it being explained clearly though.
| meh wrote: |
| If you think about the accuracy of GPS it has quite a high margin for error in measuring skiing velocities even without imprecision caused by signal errors. |
From the GTrek II specifications: 66 channels for tracking, positional accuracy of 2.5 to 3.0 m (2D-RMS), velocity accuracy of 0.1 m/s to 0.05 m/s (DGPS). Isn't that quite accurate? I don't know and I'm certainly no mathematician.
|
|
|
|
|
|
snowHeads are a friendly bunch.
snowHeads are a friendly bunch.
|
119 kph (74mph) on a smooth icy empty black with a long run-off in Bankso, Bulgaria a few years ago.
Generally hard to clock above 100kph in normal conditions. Fast carving turns will give you 35mph, a schuss around 50mph. You know when you hit 60 as the skis start to lift. Past 70mph and you're just praying for no bumps or compressions.
|
|
|
|
|
|
And love to help out and answer questions and of course, read each other's snow reports.
And love to help out and answer questions and of course, read each other's snow reports.
|
| volfy wrote: |
| You know when you hit 60 as the skis start to lift. Past 70mph and you're just praying for no bumps or compressions. |
Agreed! got up to 106 km/h over in courcheval through the week and it's pretty hair raising. Shame it was too slushy on friday to make an attempt at beating it.
|
|
|
|
|
|
|
|
|
My mates lad regularly was clocking a shade over 60mph straightlining an empty red last week. I was doing the same and the speed felt about right. Was getting a bit to fast to attempt anything more than a very gentle turn though. We have been faster on a long steep black with a big run out years ago but to be honest that was damn scary, skis were starting to bang about.
|
|
|
|
|
|
You know it makes sense.
|
|
|
|
Otherwise you'll just go on seeing the one name:
Otherwise you'll just go on seeing the one name:
|
Well, rule number one of the internet is to provide pics so here you go:-
Clocked 99kmph on the second section of the womans olympic downhill in Sansicario, right hand side of the piste on a steep bit. I wasnt even trying hard and there were no other skiers around, excpet my family behind me.
100% in control all the time and at no point a danger to anyone (except maybe myself)
|
|
|
|
|
|
Poster: A snowHead
|
| homers double wrote: |
Well, rule number one of the internet is to provide pics so here you go:-
...image...
Clocked 99kmph on the second section of the womans olympic downhill in Sansicario, right hand side of the piste on a steep bit. I wasnt even trying hard and there were no other skiers around, excpet my family behind me.
100% in control all the time and at no point a danger to anyone (except maybe myself) |
I think these apps are almost totally useless. homers double wasn't even trying hard and yet the app thinks he's done 99 km/h (61.5 mph). Unless he was on 216 cm downhill racing skis and wearing a racing suit, how is it possible to be travelling at that kind of speed?
The co-ordinates shown in the screen shot are 44°59'56.98" N and 6°52'04.33" E. In Google Earth it shows the elevation at that position as 2308 metres. In other words, the elevation on the app's screenshot differs by 203 metres. That is how 'accurate' these apps are. In my opinion they are nothing more than toys that have probably been developed using copious amounts of low quality, borrowed code that would not stand up to any proper testing scrutiny.
|
|
|
|
|
|
Obviously A snowHead isn't a real person
Obviously A snowHead isn't a real person
|
Walter-Spitty, indeed. I can't beat your forensic analysis, but I can tell you my top speed on one run increased by 10kph between the app on the phone and the google maps overlay after I'd exported.
I've done 3 official speed traps (Verbier, Courchevel & Schladming), the fasted of which was 80kph. That was on freshly waxed 178cm Missions and I was out of control, only stopping safely because they were specially separated from the regular piste with massive run-offs.
Like you, I simply do not believe that people are moving at the speeds reported without training, specialist kit and a race prepared piste.
|
|
|
|
|
|
Well, the person's real but it's just a made up name, see?
Well, the person's real but it's just a made up name, see?
|
GPS accuracy for civilian stuff ranges from about 15m to about 5m in optimal conditions with the newest kit. That's only horizontally, I believe things get worse vertically.
In the worst case then two position measurements would be 30m out from one another. Most consumer systems only update at 1Hz so your maximum possible error is going to be 30m/s in the worst case and 10m/s in the best case sans smoothing particularly for shitty devices like phones. For those that don't get metric that's approximately out by 22mph in the best conditions and as much as around 66mph in the very worst. That's without considering signal drop.
I'd put very little stock in the max speed reading from consumer devices like phones where the predominate use is one that's not expected to be high speed. Good enough for navigation not good enough for anything like accurate point speed measurement. 
|
|
|
|
|
|
You need to Login to know who's really who.
You need to Login to know who's really who.
|
Dr John, thanks for posting about the official speed traps and the type of skis you were on, as well as mentioning being out of control. That is a helpful reality check.
I'm trying to bear in mind that the title of the thread is "How fast has your gps clocked you at..." and not "What is your accurate top speed?" My motivation in questioning the quoted figures is to help people understand that free and cheap apps are free and cheap for a reason. There are very few industries in which software (and hardware) testing is carried out in a formal and systematic way, to a high level of quality. The average bit of software is rapidly cobbled together and then it is left up to the customers to report the faults, which may never be fixed.
Also, I don't want Snowheads to make themselves sound foolish when they talk about this kind of thing on ski lifts and in the bars, around racers and ex-racers. We don't always know who we might be sharing a lift with or talking to.
A good few years ago, my dad managed to embarrass himself while talking to a British skier about the Skier's Edge product that Martin Bell was selling. To cut a longer story short:
British skier: "Do you *know* Martin Bell?"
My dad: "Yes of course."
British skier: "I'm Martin Bell."
My dad: "...!?!..."
|
|
|
|
|
|
Anyway, snowHeads is much more fun if you do.
Anyway, snowHeads is much more fun if you do.
|
| Walter-Spitty wrote: |
| homers double wrote: |
Well, rule number one of the internet is to provide pics so here you go:-
...image...
Clocked 99kmph on the second section of the womans olympic downhill in Sansicario, right hand side of the piste on a steep bit. I wasnt even trying hard and there were no other skiers around, excpet my family behind me.
100% in control all the time and at no point a danger to anyone (except maybe myself) |
I think these apps are almost totally useless. homers double wasn't even trying hard and yet the app thinks he's done 99 km/h (61.5 mph). Unless he was on 216 cm downhill racing skis and wearing a racing suit, how is it possible to be travelling at that kind of speed?
The co-ordinates shown in the screen shot are 44°59'56.98" N and 6°52'04.33" E. In Google Earth it shows the elevation at that position as 2308 metres. In other words, the elevation on the app's screenshot differs by 203 metres. That is how 'accurate' these apps are. In my opinion they are nothing more than toys that have probably been developed using copious amounts of low quality, borrowed code that would not stand up to any proper testing scrutiny. |
Just a point, the screen shot of the iPhone I took wasn't at the point of maximum speed. That would be quite silly, taking a phone out whilst hurtling down a black...
Pick the sweetcorn out of that one!
|
|
|
|
|
|
You'll need to Register first of course.
You'll need to Register first of course.
|
| Quote: |
I'm trying to bear in mind that the title of the thread is "How fast has your gps clocked you at..." and not "What is your accurate top speed?"
|
Exactly why I posted my speed as mach 1 point something. I've only ever used it for walking, skiing and mountainbiking. Take yer pick which of those had me with supersonic shockwaves off my nose 
Might see if the device still shows that speed and stick up a photo. If not, can probably conjure up a GPX file, although there'll be some inevitable further filtering/processing.
|
|
|
|
|
|
|
|
Iv hit 95 kph down the speed test section in Davos and thats fast enough for me! That was tucking in a straight line on 180 GS skis (rented though).
The issue i found is that when I went back on the blue afterwards it felt really slow! I also wouldnt have fancied trying to stop myself but its designed with a nice uphill runoff so it was fine.
|
|
|
|
|
|
|
|
|
Tried 'skitracks' app on my snowboard yesterday. Clocked 58mph on a corduroy blue - I was trying a bit, not completely out of control, but defiantly letting her run. Sensation on the face didn't seem that different to that speed on a motorbike.
|
|
|
|
|
|
You'll get to see more forums and be part of the best ski club on the net.
You'll get to see more forums and be part of the best ski club on the net.
|
| homers double wrote: |
Just a point, the screen shot of the iPhone I took wasn't at the point of maximum speed. That would be quite silly, taking a phone out whilst hurtling down a black...
Pick the sweetcorn out of that one! |
In all seriousness, people don't really take their phones out and hold them, while skiing, in order to get a good GPS signal and speed reading?
|
|
|
|
|
|
|
|
|
|
|
|
|
FAQ
Otherwise, 61kph ... but only for a short distance 
