Yes, entirely possible in theory. The wings on an F1 car can generate something in the order of 5,000 kg of downforce, and the car itself weighs around 600kg.
I remember reading in a motorsport magazine that the approximate speed required to do this is 100 mph depending on wing setting.
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Whether it's possible depends on the size of the loop, as the force is equal to the rate of change of acceleration, and since you're going around a circle, you're constantly accelerating . Err - I think that's right, I haven't looked at this stuff for a year or more.
I'll work it out later today.
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Don't Alton Towers do it every few minutes?
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" IIRC, the autopilot on the Space Shuttle uses 8K (remember Ks?) of memory."
Why would they need more?. Its not like there is a whole lot up there for them to circumnavigate...or crash into.
I would bet money that the right car (probably one with no suspension and solid tyres) could do a full loop and that a loop capable of withstanding the forces could be built.
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If ,as you say a formula 1 car can in theory drive upside down, then surely to do a loop the loop in one would be a meer party trick, though if it pushes down with an equivalent weight of 5 tons the track would have to be very strong.
As an aside , working backwards ie knowing the computing power available at the time, would you be able to go to the moon with less computing power than a pocket calculator?.
I do and do not believe that it happend but the more you find out what technology was available you cannot wonder how on (and off) earth they did it,if they indeed did.
ps i would'nt ask Buzz Aldrin as he gets a bit upset when people do not believe it, didn't he lump a jounalist for asking.
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FWIW the expression in the aviation/aerobatics world is "do a loop".
The answer is yes, so long as the track and car (inc fuel system...)can handle about 3G, the vehicle has enough entry speed, and the power/traction is maintained until its done 270 of rotation.
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My parents just back from yet another SKI-ING holiday- yeah there will literally nothing left!! only joking, this time they went to China- visited one the many circuses, and there in a wall of death there were 8 motorbikes going around at various speeds, angles etc at the same time - yes they were impressed.
About 20 years ago, coming down the A3, towards the Cathedral from the Hogs back, opposite the Happy Eater, I noticed a car somehow coming over the central reservation towards me, fortunately missed, and all I saw was a car spinning behind me several times.
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The answer is yes, so long as the track and car (inc fuel system...)can handle about 3G, the vehicle has enough entry speed, and the power/traction is maintained until its done 270 of rotation.
Ah , but what i am saying is, if the downforce from the spoilers is so immense that upside down the force is upwards pushing the car down,up.
Erm ,yes that's right , so as long as you are moving forward with enough speed to push the vehicle down/up enough that it does not fall off/up then it will carry on , i think ?.
Will the force pushing the car down/up also stop the fuel/oil falling up ?.
Gosh i am going to have to lie down
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>>a formula 1 car can in theory drive upside down, then surely to do a loop the loop in one would be a meer party trick>>
Christian Fittipaldi managed a loop the loop in a Minardi F1 car at the chequrerd flag at the Italian Grand Prix, Monza in 1993.
He passed over the line whilst upside down and was classified 8th!!
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It's a very long time since my heavy maths days, but does this loop have to be so strong? If the car was travelling at just enough speed to complete the loop succesfully then at the top the forces would be balanced. Acceleration of g = to acceleration force keeping it there. Result: no load on top of loop at all. It's either that or the pre-dinner drink !
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"Will the force pushing the car down/up also stop the fuel/oil falling up ?."
No. The upward force would be generated by the movement of the car through air. All the oil and fuel would gather at the top (now the bottom) of their respective containers.
On a related point, this was a weak point in the Merlin engine. As the pilot pushed the stick forward, the fuel in the carburettors would suffer negative G and the engine would be starved of fuel, leading to misfiring. Bf109s, being fuel injected, didn't suffer the problem. Spitfires and Hurricanes had to roll into a dive to avoid the problem, which added enough time to the manoeuvre to leave them at a disadvantage.
Fatscinating stuff, inertia and gravity.
V
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''ps i would'nt ask Buzz Aldrin as he gets a bit upset when people do not believe it, didn't he lump a jounalist for asking.''
not motoring related, I know, but yes he did once deck a sceptic who collared him at some sort of convention. Can't say I blame him myself.
S6 1SW
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The incident is described in very funny detail in the excellent book Moondust.
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"As an aside , working backwards ie knowing the computing power available at the time, would you be able to go to the moon with less computing power than a pocket calculator?.
I do and do not believe that it happend but the more you find out what technology was available you cannot wonder how on (and off) earth they did it,if they indeed did."
How difficult can it be? Huge rocket, aim at moon, light blue touch paper and stand back. If you gave me a couple of hundred billion dollars, I'd land you on the moon. Physics is a simple science. Biology is where you have to put your thinking cap on.
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You can certainly loop the loop in a car. The problem is to find the loop of road to do it on. When looping the loop all fuel, driver and fluids would be kept in their usual positions by centrifugal force. The problems experienced by carburetted Merlin engined fighters when attempting an 'outside loop' or simply going into a steep dive without rolling would not be present.
I wouldn't be at all surprised if the bit of road didn't exist somewhere. US? Japan?
It would have to be somewhere with more money than sense though, because it wd cost quite a bit and would be more or less pointless.
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"The problems experienced by carburetted Merlin engined fighters when attempting an 'outside loop' or simply going into a steep dive without rolling would not be present. "
Except that if you read the original post to which I was responding, you'll note that it was referring (or appeared to be referring) to F1 cars being able to drive on the roof, in which case, it would only be aerodynamic forces holding them up, so the oil and petrol would indeed slosh the wrong way.
V
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I did notice that Vin, I didn't think you didn't know that, was just pointing it out in case anyone thought that only an F1 car doing 150mph could loop the loop. Depending on the size of the loop, 40 or 50 ought to do the trick... wouldn't feel very nice though.
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Oil and petrol does not slosh in F1 cars. Sloshing fluids would severelyupset the balance and handling. F1 cars tend not spill petrol anywhere when they are smashed to bits either. all fluids in F1 cars are contained by baffles
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TourVanMan TM < Ex RF >
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On an episode of Jackass, the guys built a plywood loop and after a few attempts managed to loop it on a skateboard and a BMX bike. It had a long ramp to enable them to build up speed.
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This is from New Scientist in 1999, answering precisely this question:
Transport 08 05 1999 Cars go loopy Can a car loop the loop?
I have just seen a TV advert in which a car travels along a straight track which then veers upwards to loop the loop before returning to ground level. The car follows the road without falling off, even when it is upside down at the top of the loop. Special effects aside, can a car loop the loop, and, if so, how fast would it have to travel?
Scott Croston Manchester
SURPRISINGLY , the minimum speed a car must be travelling at to loop the loop depends only on the force of gravity and radius of the loop. The speed required does not vary with the mass of the car. This is because to loop the loop the force flinging the car outwards (centrifugal force) must equal the weight of the car at the top of the loop. The equation for both forces is the same (mass x acceleration), so the mass can be cancelled from the calculation.
Many a schoolchild is puzzled by the difference between weight and mass and this problem highlights the difference. The car's weight is the force pulling it down and is given by mass multiplied by acceleration due to the gravitational attraction of the Earth. For a car of mass M kilograms this is M x 9.81 newtons.
To counter this the car must be travelling fast enough for the centrifugal force to equal this at the top of the loop. If the radius of the loop is r metres and the velocity of the car is v metres per second, the formula for this is M x v2/r. Equating these two opposing forces and cancelling M gives 9.81 = v2/r, remembering that velocity is in metres per second and radius in metres.
So for a 10-metre radius the car must be travelling at the square root of 98.1 metres per second, or about 10 metres per second. That's 36 kilometres per hour.
This is surprisingly low, but remember it's the speed required at the top of the loop after climbing, so a higher speed would be required at the bottom. An obvious question leading on from this is from what height would a car have to freewheel to loop the loop?
This time the answer does not even depend on gravity. The above equations give v2 = r x 9.81 for the minimum speed at the top of the loop. Equating potential energy gained by falling from height h metres with kinetic energy gained at velocity v gives 0.5 M x v2 = M x 9.81 x h or v2 = 2 x 9.81 x h. Combining the two equations gives r x 9.81 = 2 x 9.81 x h or h = r/2
In other words, dropping from half a radius higher than the top of the loop is sufficient (though friction losses would in practice necessitate a greater height). This seems remarkably small and I did not believe it, until trying it with a marble and flexible curtain track made it seem plausible.
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Superb CP. End of thread!
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Time to start a thread 'How do I build a 10m radius loop for my car?'
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