100 MPH (160 km/hr) on 1-hp/746 Watts

[aerohead]

Originally Posted by niky

I'd like to see them actually hit 100 mph at sea level.

But that's insane... does the man have Martian lungs?

They're essentially 'Olympians',one and all. Physically and kinematically best-suited to the task.
Or having so much fun doing it that you'd never keep them away!

[redpoint5]

It should be a simple matter to calculate the HP required to achieve 100mph once you know the weight, CD, and frontal area. Are these figures published somewhere?

...and there is no way that the added oxygen at sea level would more than offset the increased atmospheric drag. As pointed out, these sprints are an anaerobic exercise. The best speed could be achieved by riding a standard road bike in a vacuum while the rider holds his breath.

[aerohead]

Originally Posted by redpoint5

It should be a simple matter to calculate the HP required to achieve 100mph once you know the weight, CD, and frontal area. Are these figures published somewhere?

...and there is no way that the added oxygen at sea level would more than offset the increased atmospheric drag. As pointed out, these sprints are an anaerobic exercise. The best speed could be achieved by riding a standard road bike in a vacuum while the rider holds his breath.

I did see a paper online the other day but did not snag it.I caught a glimpse of a CdA in a table.Something like 0.063 meters squared.It was at an extremely small image scale.
The bike should be below Cd 0.11 and frontal area should be around 4-sq-ft.Weight should be in neighborhood of 200-lbs with rider.Just SWAG.

[arcosine]

The bikes go faster at altitude, not slower, thats why they run up in the high desert at BM. You won't see a 100 mph run this decade.

[sheepdog 44]

Well this was supposed to be capable of 100mph. But he only got it to 56mph average. A little disappointing. Maybe a tandem could break 100mph? If they allowed this stuff on the tour de France could you imagine the contraptions they would make?

Flying Scotsman's "Beastie" to be first human-powered vehicle to achieve 100 mph on the flat?

Breathing: The Graeme Obree way on Vimeo

[kennybobby]

The air density at sea level is ~20% greater than that at 4500 ft, so the 200 lbs, .0005 crr, .11 cd, 4 sf vehicle at sea level requires 800 watts to go 71 mph. In the thinner air it goes 15% faster (82 mph) for the same power.

It looks like they had a clever 'starter' motor--a big-legged sprinter pushing a thin inline skater pushing the vehicle. i reckon they might get him up to nearly 40 mph before he had to start putting his legs into it.

An awesome achievement for sure...

[jamesqf]

Originally Posted by RedDevil

The reason they went there is the lower resistance at altitude.

Not really, because it's only at 4500 ft, which is not particularly high altitude. There are mines around here that don't get down to that level :-) The reason they have the races there (AFAIK, anyway) is that there's a nice stretch of straight, flat highway with next to no traffic that the NHP will let them use.

Of course the rider has less oxygen too and cannot get as much oxygen an will produce slightly less power...

Not exactly true. The limiting factor (up to altitudes quite a bit higher than that) is the oxygen-carrying capacity of the blood. If you train at those altitudes for a week or two (or live there), the body responds by producing more red blood cells, so as to have the same oxygen-transporting capacity. That's why it's not uncommon for Olympic athletes to train in Colorado or other such higher-elevation places. Unfortunately, though, the body reverses the adaption fairly quickly when you return to lower elevations. See e.g. Altitude training - Wikipedia, the free encyclopedia

[Otto]

Since aerodynamic drag goes up exponentially, going 100 mph is a huge extra burden beyond 82 mph, so we won't likely see 100 mph anytime soon.

That said, I wonder if the HPV crowd has studied Hoerner or Carmichael as much as they might, or should.

[RedDevil]

Originally Posted by jamesqf

Not really, because it's only at 4500 ft, which is not particularly high altitude. There are mines around here that don't get down to that level :-) The reason they have the races there (AFAIK, anyway) is that there's a nice stretch of straight, flat highway with next to no traffic that the NHP will let them use.

Not exactly true. The limiting factor (up to altitudes quite a bit higher than that) is the oxygen-carrying capacity of the blood. If you train at those altitudes for a week or two (or live there), the body responds by producing more red blood cells, so as to have the same oxygen-transporting capacity. That's why it's not uncommon for Olympic athletes to train in Colorado or other such higher-elevation places. Unfortunately, though, the body reverses the adaption fairly quickly when you return to lower elevations. See e.g. Altitude training - Wikipedia, the free encyclopedia

Hey, I did not make that up myself.
Please check the facts at Human Power Team Delft & Amsterdam. There is a wealth of information about the whole event there.

[jjackstone]

"It looks like they had a clever 'starter' motor--a big-legged sprinter pushing a thin inline skater pushing the vehicle. i reckon they might get him up to nearly 40 mph before he had to start putting his legs into it."

Closer to 15 or 20mph. The pusher is only allowed for 15 meters and the skater is not allowed to input power.

Note that the low altitude record is "only" about 62 mph.

IHPVA - International Human Powered Vehicle Association

The reasons for choosing this site are a combination of the reasons previously stated. Long run up to the 200 meter timing traps(5 miles), relatively flat(.66% slope), smooth road at a relatively high altitude for less air resistance.

If the new speed record were equivalent to 100mph at sea level, I'm fairly certain that Delft or Sam would have found a suitable place to race so that they would be able to say they were the first human powered vehicle to reach 100mph.

JJ