Driving on the ceiling

September 11, 2006 7:05 AM

It's often quoted that a Formula 1 race car creates enough aerodynamic downforce to let you drive it across the ceiling. Has anyone ever proved this? If not, why not?
posted by twine42 to Science & Nature (34 answers total)

Response by poster: By the way, I'm not suggesting that you could do this on your bedroom ceiling... I just can't believe taht no-one has built a 'barrelroll' type track to prove the point on. Yeah, it would be expensive, but in F1 budgetry terms, it's sod all.
posted by twine42 at 7:10 AM on September 11, 2006

because you'd have to get it up on the ceiling first, F1 cars have very little ground clearance, so any ramp would have to be really big. Also, if something goes wrong, that's a really expensive car to wreck.
posted by atrazine at 7:11 AM on September 11, 2006

From Wikipedia:

Such an extreme level of aerodynamic development means that an F1 car produces much more downforce than any other open-wheel formula; for example the Indycars produce downforce equal to their weight at 190 km/h, while an F1 car achieves the same downforce:weight ratio of 1:1 at 125km/h to 130km/h, and at 190km/h the ratio is roughly 2:1. Therefore, theoretically, F1 cars can drive upside down from 130km/h.

Whaddya mean why haven't they done this? Um...cost of building a road where one could gradually spiral into this position at over 130km/h, the possibility of something breaking and losing downforce etc.

This is one of those situations where the theory is enough.
posted by jimmythefish at 7:12 AM on September 11, 2006

Best answer: Oh, also, it may not actually be possible. An F1 car does create enough downforce to support its own weight, but only at high speed. I don't know if there is enough 'spare' downforce to maintain traction (and thus, speed) with the weight of the car pulling the wheels away from the surface.
posted by atrazine at 7:14 AM on September 11, 2006

Best answer: Easier than building a monster spiral road would be to put one in a wind tunnel strapped to a ceiling then as wind speed increases loosen the straps...
posted by zeoslap at 7:40 AM on September 11, 2006

Aside from the traction problem (great call, atrazine), some systems on Formula One cars are probably gravity fed.
posted by Chuckles at 8:01 AM on September 11, 2006

atrazine is onto something. The wiki article says the downforce generated at 130 km/h is 1:1 -- in other words, equal to the force of gravity (call it Fg) pulling the car downward. So the total downward force acting on the car is 2·Fg. Put the car on the ceiling, and the two equal forces are now acting in opposing directions and cancel each other out. The would be no force keeping the tires on the ceiling.

At 190km/h, it's a different story. Since the ratio of downforce to weight is 2:1 at that speed, turning the car upside down would result in an "upforce" equal to the weight of the car. It would be as if the car were driving right side up with no downforce. E.g. Theorerically, it would stay on the ceiling.

And zeoslap's test method is the way to go.
posted by pmbuko at 8:03 AM on September 11, 2006

Enough already, someone should contact asavage and have him and his fancy tv show prove this once and for all.
posted by SteveFlamingo at 10:04 AM on September 11, 2006

This would make for a sweet Mythbusters.
posted by dead_ at 10:22 AM on September 11, 2006

Dang. Beat me.
posted by dead_ at 10:23 AM on September 11, 2006

There's an easier way. Put the car into a wind tunnel on top of a large scale. Tare the scale, then fire up the turbines. When the scale reads the same as the weight of the car, you've reached the speed at which it could theoretically hang upside down.

No actual upside-downness required.
posted by chrisamiller at 10:38 AM on September 11, 2006

chrisamiller: But then you don't get to see the car hanging upside down from the ceiling...
posted by zeoslap at 11:02 AM on September 11, 2006

And yet, I don't think anyone here is looking for mere simple proof. I think we're looking for an actual upside-down-driving F1 car, am I right?
posted by Imperfect at 11:06 AM on September 11, 2006

Response by poster: I have to say, I do indeed want to see schumacker hanging from the ceiling, but hanging the car from the ceiling in a wind tunnel is a damned good idea too!

Lets be honest here... how many of us know important things but never really believed them til they saw them? I don't care how we do it, I just want my upside down F1 car, godamnit! :)
posted by twine42 at 11:12 AM on September 11, 2006

It's possible. I've had discussions about it, if you took the car hypothetically through a corkscrew or something, however there are many risks involved (traction, side force) that would put the driver in extreme peril if it were to fall (effectively killing he/she).

Why haven't they tested it? Why would they design a facility and test a $14 million car in order to prove a physical factoid?

btw, a lot of street cars can produce enough downforce at certain speeds to ascertain this as well...
posted by stratastar at 11:27 AM on September 11, 2006

let me rephrase one last point: getting the car in that position where it will drive upside down is the hard-part. Any externalized force could throw it out of wack and cause it to fall. How to minimalize those externalities en route to getting the car upside down? Very difficult...
posted by stratastar at 11:32 AM on September 11, 2006

It's not possible for the cars as they are currently design. There are many pants of the engine and gearbox that depend on gravity to function - the lubrication system, for example.
posted by milinar at 11:52 AM on September 11, 2006

unless they're actually racing upside down i can't see that it's very interesting.
posted by londongeezer at 1:07 PM on September 11, 2006

I could see a market for Inverted Drag Racing. They're equipped with parachutes, aren't they?
posted by yeti at 1:28 PM on September 11, 2006

Why would they design a facility and test a $14 million car in order to prove a physical factoid?

I, for one, would actually watch an F1 race if it included an upside-down portion of track. I would pay, dearly, to see it live with a bigass beer in my hand, right where they go upside-down and where the highest risk of a crash was. Why, dear stratastar, because it would be freaking awesome.
posted by jmgorman at 1:45 PM on September 11, 2006

chrisamiller: But then you don't get to see the car hanging upside down from the ceiling...

That's why you turn the camera upside down. Eh? EH? *tapping nose*

*conspiratorial look*
posted by scrump at 2:54 PM on September 11, 2006

I think we're looking for an actual upside-down-driving F1 car, am I right?

Well, I wasn't, at least until you typed this. Now, I find myself bereft at the thought of a world that lacks one.
posted by scrump at 2:58 PM on September 11, 2006

Response by poster: It's not possible for the cars as they are currently design. There are many pants of the engine and gearbox that depend on gravity to function - the lubrication system, for example.

Erm... that point is irrelevant... when the car is upside down at 2g then (from the car's perspective) gravity is pointing up, towards the underside of the car, exactly as is expected.
posted by twine42 at 3:52 PM on September 11, 2006

twine42.. I don't know how to put this gently.. And I guess you could be joking or intentionally twisting language, or something, but..

I mean, we aren't talking about centrifical force as you go around a loop here.. We are talking about the aerodynamic down force. How exactly is air flow supposed to hold the gas in the fuel tank, or the oil in the oil pan, or the tiny little chunks of metal in the oil pan, up?
posted by Chuckles at 4:02 PM on September 11, 2006

Exactly, Chuckles. It's the same type of force as an airplane's wings. In order to complete an entire race upside-down, you'd have to have some serious re-engineering of the cars.
posted by chrisamiller at 4:56 PM on September 11, 2006

It's not possible for the cars as they are currently design. There are many pants of the engine and gearbox that depend on gravity to function - the lubrication system, for example.

I highly doubt this. Depending on the course being driven, F1 cars can accelerate at 1.5g, decelerate at up to 5.0g and corner at up to 5.0g. Under such extreme conditions, it would be impossible for gravity-fed lubrication or fuel systems to function reliably. They must certainly rely on pressurized fluid reservoirs that would keep the car running while driven upside down.
posted by randomstriker at 5:11 PM on September 11, 2006

God. Now I don't know if I can live another day without someone starting the FLICR (Freestyle League for Indycar Ceiling Races)

Seriously. This would make those X-gamers look like a bunch of Nancys.
posted by rileyray3000 at 6:58 PM on September 11, 2006

At 130 km/h thereare 2Fg's on the ground. This presummably improves traction to more easily obtain the 190 km/h neccessary for 3Fg's. If you subtract natural gravity, 1Fg, and count it it against it as it would racing on the ceiling, [another 1 Fg] you'd have a net 1Fg towards the ceiling. But how much more work would the car need to perform to reach 190 km/h with only 1 Fg instead of the 3Fg's is has to it's advantage on the ground.

Ceiling cat is watching you race.
posted by yeti at 7:36 PM on September 11, 2006

Well duh, mount the engine upside down.

Also: There is ALWAYS 1g pulling down. Lift can counteract it, but people on airplanes don't stick to the ceiling, however cool that might be.

Also #2: Upside-down race tracks suspended from zepplins, 1 mile up. There's your freakin' NASCAR of the future.
posted by blue_beetle at 8:44 PM on September 11, 2006

They must certainly rely on pressurized fluid reservoirs that would keep the car running while driven upside down.

I'm quite certain they'd run out of gas.

The gas tank works like this... there are multiple gas tanks (with one way doors) inside the fuel bladder. Inside the "main" tank (the lowest one), there is a cylinder. Small pumps at each corner of the main tank fill that cylinder. A pump inside that cylinder is used to actually fuel the engine.

Turned upside down, this would all fail quite horribly.

I'm not sure how oil is procured, but it seems likely that the dry sump system could fail as well, if it also starts with an assumption that gravity pulls things down.
posted by Tacos Are Pretty Great at 9:30 PM on September 11, 2006

Oh, and the other problem. If an engine or tire went ka-blammo while it was upside down, you'd have a truly hellish safety issue.
posted by Tacos Are Pretty Great at 9:31 PM on September 11, 2006

Response by poster: twine42.. I don't know how to put this gently..

Bwuahaha - good point. This is why I should keep away from the net at midnight... I'd just finished having a conversation about perfect +1g barrel rolls in commuter jets...
posted by twine42 at 8:40 AM on September 12, 2006

I don't think reengineering the car to work upside down would be that hard. Certanly less of a challange then building an upside down track.
posted by delmoi at 10:08 AM on September 16, 2006

delmoi: it has to work right side up *and* upside down, though.

If it *just* had to work upside down, no prob. But engineering everything to work with gravity being in a purely random direction... that seems like a hell of a lot of work for something that would just be a one-off gimmick with no practical value.
posted by Tacos Are Pretty Great at 11:03 PM on September 20, 2006