You don't need to be an 'investor' to invest in Singletrack: 6 days left: 95% of target - Find out more
Right - I was thinking about this last night.
Picture A Hercules (or similar)...flying low and slow along the runway with the ramp down...like when they are dropping out pallets
...could I (well Danny Mackaskil more like) ride out down the ramp of the herc, drop onto the runway and ride away...all nice and smooth.
Is this the sort of super trick where you hit the runway facing backwards at 150mph? It's going to have to be nailed first time out.
If you can land a drop to flat at 100kts then hell yeah!
Is the fan running at the same speed as the treadmill?
Min Herc speed 110-120 but in practice can be dragged down to 70-80 depending on weight and getting into ground effect. So theoretically with a 30 headwind one would drop out at 40-50, and as above points out backwards. Motorcrosser could make it but doubt any bike would.
Bit like the Italian Job in reverse (swap Herc for bus, bike for mini)
so yes because they did it in the film.
A strong (30kt) headwind for the herc would translate to a strong tailwind for the rider though so probably harder to control...
what if the runway was a conveyor belt?
sorry
Don't know about the physics, but I'd pay good money to see it attempted.
Bonus points if the low flying Hercules is deploying chaff/ flares for the duration of the low pass.[img] 
[/img]
Needs MOAR gunz!
[img] 
[/img]
So could you do it on a motorbike - that probably could hit 50 mph before the exit of the plane ...?
If he lands ths without deploying then, YES.
Try a tank?
Theres an airshow display routine where a bunch of soldiers drive a landie of a slow moving herc thats done a steep descent onto the runway. They drive around the airfield shooting stuff up whilst the herc goes round again and then drive back onto it as its taxing down runway and the piolot takes off again. I'm pretty sure the herc is always on the ground during entry/exit though.
Try a tank?
I think that must be how Tredz delivered my Kinesis frame
boat into the back of a chinnock is close
Boat into chopper, a proper 'will it go?' stunt.
A strong (30kt) headwind for the herc would translate to a strong tailwind for the rider though so probably harder to control...
Shirley you would have to hop off backwards so that you were effectively traveling at the same speed as the plane, facing the right way.
If you rode down the plane and jumped off the back your ground speed would be the ground speed of the plane minus the speed you could accelerate up to over the length of the plane. Even on a crosser at best you would only get to a ground speed of close to zero. 😯
Something similar to this done on mythbusters.
Guy vector vengeance I think they called it.
I reckon if the herc was going as slow as possible, and Mr Macaskill was riding backwards towards to the ramp - i.e. facing the front of the plane, but travelling backwards - then he did one of those annoyingly-easy-looking-anti-gravity-hops off the end of the ramp, he'd effectively hit the ground the same as if he'd just done a small jump off a ramp at 50mph, or whatever the plane's equivalent ground speed was. Might be a bit hairy for second or two but I'm sure not that dramatic compared to some of the stuff he's done before.
Why do you want to kill Mr MacAskill???????
Why do you want to [b]s[/b]kill Mr MacAskill???????
If Danny was on rollers spinning at 50mph facing the front of the plane, then hopped backwards and out, surely he'd hardly notice it? Be like a high-speed bunny hop effectively.
Why do you think he has to match wheel speed? Bike wheels are only light, there'd be a little bit of skidding but they'd soon accelerate, cos bikes have a freewheel.
All he'd have to do would be ride off the ramp and do a perfect 180, simple 🙂
Having a freewheel would make it too easy, do it on a fixie.
I think we need more information on tyres?
FWIW I think it would be impossible on 26" wheels and hard on 29" ones. However, 650B would be spot on making it a lot easier.
So it looks like we're going with this proposition...
Min air speed
Moderate Headwind
Maximum acceleration off the rear-facing ramp
Perform 180 before landing
Simple. Anybody got Danny's number?
How did Knight Rider used to drive out of the back of the moving truck? Trying to find it on youtube. Got to be something similar...
What about if there is a jump at the end of the planes ramp the rider gets loads of air, the more air time the more he will slow down. So when he lands it might be close to 0 speed perhaps an STW aerodynamist could run the numbers?
What about if there is a jump at the end of the planes ramp the rider gets loads of air, the more air time the more he will slow down. So when he lands it might be close to 0 speed perhaps an STW aerodynamist could run the numbers?
I am not an aerodynamist but on the face of it this seems like a good way to die.
Drag varies with the square of air speed making the equation tricky (there is less drag as Danny's ground speed reduces) but by my reckoning it would take over 10s for a cyclist to be slowed from 50mph to zero purely by wind resistance, even with a 30 mph headwind.
So to be high enough off the ground to have enough time for this to happen as he falls Danny is going to have to have a max heigh of something around 500m (very approximately)
But anyway a human will hit terminal velocity in around 5s of freefall so basically whatever Danny does if he wants to have a ground speed of 0mph he is going to hit the tarmac at terminal velocity, which for a person is about 120mph. Best get some strong rims!
I'm sure he'd be OK with a ground speed of say 40mph, just so long as he gets the mid-air 180 right first 😉
[STW pedant] Aerodynamicist [/STW pedant]
On a flat, smooth runway the speed across the ground is pretty irrelevant. Assuming you don't fall off, then more speed=more death.
But a 3ft drop to flat at 50mph is the same (in theory, ignoring any speed wobble etc) as a 3ft drop to flat at 10 or 0mph.
By launching up into the air to lose horizontal speed you gain a load of vertical speed so you plough into the ground and your knees end up where your ankles used to be.
How did Knight Rider used to drive out of the back of the moving truck?
In neutral, I'd imagine.
OK, so landing backward no, but if he rode down the ramp backwards so landed in the right direction of travel yeah why not...
If there was a conveyor belt, going at the same speed as the aircraft but in the opposite direction, as in the classic scenario, then yes, you could just ride out of the plane and onto the conveyor belt (as far as I can tell)!
How you going to get off a conveyor belt doing 150mph though?
If there was a conveyor belt, going at the same speed as the aircraft but in the opposite direction, as in the classic scenario, then yes, you could just ride out of the plane and onto the conveyor belt (as far as I can tell)!
... no, that's not going to work is it?
…if the conveyor belt was going in the same direction as the aircraft (reversed from the original scenario), you could just plop out of the plane onto the belt.
You'd be pedalling forwards at your own speed, but going backwards at your speed minus 150mph ... ...you'd need to get your 180 in before you got spat off the end of the conveyor belt at 150mph ...
Is that right?