"right to use the pitlane every lap"

[GolddustMini]

if this has been covered before then please merge with the neccesary thread.

now its a well known right that the teams can use the pitlane every lap if they so wish and this was something pointed to in the fia statement.

now what im thinking is that, yes the pitlane is dangerous, people work mear inches away from cars passing at 50mph. people also cross the pitlane to get to the pitwall to pass messages etc. so is it really safe to have 14 cars going through the pits every lap nose to tail through the pits and then dragging out of the pits again, only to return to the pits, slam on the brakes for the limiter line and bounce of the limitter for a while and then out again. its bound to lead to an accident, especially as the driver behind would not know if the car infront was simply passing through or "in for business". too cars contact, debris everywhere, pit crew get squashed, i think you'll find that that isnt a safe situation.

anyone who has ever worked in a pitlane can justify that they are dangerous places to be in. and the less cars that pass through the better.

cars are dangerous things at any speed, thats why there are barriers on the curcuit and marshals are not allowed on the track when cars are passing...

just my 2 cents

[Don K]

Originally Posted by GolddustMini

if this has been covered before then please merge with the neccesary thread.

now its a well known right that the teams can use the pitlane every lap if they so wish and this was something pointed to in the fia statement.

now what im thinking is that, yes the pitlane is dangerous, people work mear inches away from cars passing at 50mph.

As far as I know, the pit lane at Indianapolis is *a lot* wider than that.

[Don K]

Originally Posted by GolddustMini

so is it really safe to have 14 cars going through the pits every lap nose to tail through the pits ...

Why on earth would they go nose-to-tail?

They are in a race.
They would only have a chance to go nose to tail, if each of those cars would make equal lap times.

[GolddustMini]

Originally Posted by Don K

Why on earth would they go nose-to-tail?

They are in a race.
They would only have a chance to go nose to tail, if each of those cars would make equal lap times.

because at slow speed cars close up, (just watch at a corner) add this to the fact that people would be using the pitlane speed limit line as a break test to gain valuable tenths. and as mentioned 2 abreast in the pitlane entry would be disasterous. its just a rediculous idea, similar to the entire USGP weekend really.

imagine the disaster if a car skidded into a refueling car, you've got fuel everywhere, you've got injured marshals, the pitlane (and refueling) is dangerous anyway, let alone with 14 cars using it as a start finish line every lap.

people seem to forget that whilst comparitavely to 230mph the pitlane speedlimit is low, however its still quicker than most roads....

[mac]

My only concern with that would be drivers possibly using the pit speed limit line as a braking point to try and pass at - the pit entry road is not really wide enough for that.

Other than that I don't have too many dramas with the notion.

[Marbot]

Using the pitlane as part of the racetrack is a really dangerous idea.The chance of a collision during refuelling would be greatly increased.

[BootsOntheSide]

Theoretically everyone would be at the same speed down the pitlane, but it's bad enough when a car tries to pull out of the pitlane just as another is passing through having already stopped. The situation of drivers leaving their braking as late as possible, and perhaps attempting to enter the main pitlane 2-abreast, would not be safe for the pitcrews (if Indy's pitlane is theoretically wide enough for this, the situation is paradoxically even worse). Not only that, but the situation of cars exiting the pitlane across another's path (as Michael did to Rubens in the race) would happen dozens of times. In my mind Michaelin were quite right to reject this impractical and dangerous solution.

[John Turner]

Originally Posted by BootsOntheSide

In my mind Michelin were quite right to reject this impractical and dangerous solution.

Quite right Boots! What's more, what sort of race or racing spectacle would that have provided. I can't believe anyone seriously considered this a sensible option.

[Don K]

Originally Posted by BootsOntheSide

Theoretically everyone would be at the same speed down the pitlane, but it's bad enough when a car tries to pull out of the pitlane just as another is passing through having already stopped. The situation of drivers leaving their braking as late as possible, and perhaps attempting to enter the main pitlane 2-abreast, would not be safe for the pitcrews (if Indy's pitlane is theoretically wide enough for this, the situation is paradoxically even worse). Not only that, but the situation of cars exiting the pitlane across another's path (as Michael did to Rubens in the race) would happen dozens of times. In my mind Michaelin were quite right to reject this impractical and dangerous solution.

Actually, according to traffic flow theory (D.L. Gerlough), a road is considered to be safe for pedestrians crossing the road, as soon as there is on average one possiblity per minute to cross the road safely.

For a road of 9 meters wide (or smaller), this means that it is safe for pedestrians as long as no more than 750 cars per hour pass.



In this case, I would expect the Michelin cars to need about 85 seconds for a lap (including the pit lane).
That would mean that each Michelin car would pass through the pit lane about 42 times per hour.
That would mean that 14 Michelin cars would pass through the pit lane about 14*42= 588 times per hour.
If the Bridgestone teams would make 2 pit stops per hour, that woule mean a total of 12 passes per hour of a Bridgestone car through the pit lane.

Which would mean a total of 588+12= 600 cars per hour.
Well below the maximum of 750 cars per hour.


In other words, as long as the 'fast lane' of the pit lane has a width of 9 meters or less, traffic flow theory dictates that it is a safe situation.

(If we would extrapolate the same formula for lanes that are slightly wider than 9 meters, the situation would remain safe until a width of 10.47 meters).

[GolddustMini]

Originally Posted by Don K

Actually, according to traffic flow theory (D.L. Gerlough), a road is considered to be safe for pedestrians crossing the road, as soon as there is on average one possiblity per minute to cross the road safely.

For a road of 9 meters wide (or smaller), this means that it is safe for pedestrians as long as no more than 750 cars per hour pass.



In this case, I would expect the Michelin cars to need about 85 seconds for a lap (including the pit lane).
That would mean that each Michelin car would pass through the pit lane about 42 times per hour.
That would mean that 14 Michelin cars would pass through the pit lane about 14*42= 588 times per hour.
If the Bridgestone teams would make 2 pit stops per hour, that woule mean a total of 12 passes per hour of a Bridgestone car through the pit lane.

Which would mean a total of 588+12= 600 cars per hour.
Well below the maximum of 750 cars per hour.


In other words, as long as the 'fast lane' of the pit lane has a width of 9 meters or less, traffic flow theory dictates that it is a safe situation.

(If we would extrapolate the same formula for lanes that are slightly wider than 9 meters, the situation would remain safe until a width of 10.47 meters).

and then you realise that this is racing and these are racing drivers your talking about and predicatabilty goes out of the window

[Don K]

Originally Posted by GolddustMini

and then you realise that this is racing and these are racing drivers your talking about and predicatabilty goes out of the window

I would say that predictability goes up, rather than down.

We could certainly expect *all* of those cars to have the same speed.
Which we could *not* expect at a normal road.

[Don K]

Originally Posted by GolddustMini

and then you realise that this is racing and these are racing drivers your talking about and predicatabilty goes out of the window

In case you are talking about my expectation that the cars would lap in 85 seconds:

If some of the cars would be lapping slower, there would be even *less than* 600 cars passing through the pit lane -- making it even more safe ...

[Don K]

Originally Posted by GolddustMini

and then you realise that this is racing and these are racing drivers your talking about and predicatabilty goes out of the window

In case you are talking about expected number of gaps big enough for walking across the pit lane:
That's probably just a simple Poisson distribution.

So with racing drivers, it would work out exactly the same as with any other kind of driver.

[Testure]

Originally Posted by Don K

Actually, according to traffic flow theory (D.L. Gerlough), a road is considered to be safe for pedestrians crossing the road, as soon as there is on average one possiblity per minute to cross the road safely.

For a road of 9 meters wide (or smaller), this means that it is safe for pedestrians as long as no more than 750 cars per hour pass.



In this case, I would expect the Michelin cars to need about 85 seconds for a lap (including the pit lane).
That would mean that each Michelin car would pass through the pit lane about 42 times per hour.
That would mean that 14 Michelin cars would pass through the pit lane about 14*42= 588 times per hour.
If the Bridgestone teams would make 2 pit stops per hour, that woule mean a total of 12 passes per hour of a Bridgestone car through the pit lane.

Which would mean a total of 588+12= 600 cars per hour.
Well below the maximum of 750 cars per hour.


In other words, as long as the 'fast lane' of the pit lane has a width of 9 meters or less, traffic flow theory dictates that it is a safe situation.

(If we would extrapolate the same formula for lanes that are slightly wider than 9 meters, the situation would remain safe until a width of 10.47 meters).

Don, I think your statistics are too simplistic to be of much use. You're trying to view the group of cars too much as a group of equals; I think we would need to consider it at a level "above" that... A few points of data occur:

Even with the cars travelling through the pit lane every lap, and thus travelling at equal speed for that portion of the lap, the variance in complete lap time of each car in the field of 20 would be much the same as always. Certainly, it would follow the same basic pattern as at any other race.

Lap times change considerably over the course of fuel "stints". Further, different cars show different variances in that variance, even the same makes of cars. Car setup and driving style affect this.

Every car chooses it's own race strategy and, thus, the length of the stints into which it divides it's race. So, every car will potentially need to pit for fuel at a different lap to every other car. Once back into the race, the car will be operating at a different sequence to its peers. Perhaps you could have each car divide the race into the same number of stints, but the first two points negate any benefit to that (in my opinion).

Using the pitlane changes the rate of fuel consumption and, presumably, would affect the decision on how many fuel stops would be required. There's too many small details like this to think of the problem "statically", it's much more dynamic.

Also, I would suspect that the particular dynamics of a racing pitlane would conflict with the set of assumptions made in the study you quote. For example - it's been noted that the Indy pitlane is particularly wide. Your profile says that you can program - it would be a straightforward exercise to code up a little simulation of all this.


And now that I've surely sent the population of this board into a deep coma I'd just like to say: "boink" and pull a silly face. Thanks

[Don K]

Originally Posted by Testure

Don, I think your statistics are too simplistic to be of much use. You're trying to view the group of cars too much as a group of equals; I think we would need to consider it at a level "above" that... A few points of data occur:

Even with the cars travelling through the pit lane every lap, and thus travelling at equal speed for that portion of the lap, the variance in complete lap time of each car in the field of 20 would be much the same as always. Certainly, it would follow the same basic pattern as at any other race.

Lap times change considerably over the course of fuel "stints". Further, different cars show different variances in that variance, even the same makes of cars. Car setup and driving style affect this.

Every car chooses it's own race strategy and, thus, the length of the stints into which it divides it's race. So, every car will potentially need to pit for fuel at a different lap to every other car. Once back into the race, the car will be operating at a different sequence to its peers. Perhaps you could have each car divide the race into the same number of stints, but the first two points negate any benefit to that (in my opinion).

Using the pitlane changes the rate of fuel consumption and, presumably, would affect the decision on how many fuel stops would be required. There's too many small details like this to think of the problem "statically", it's much more dynamic.

Also, I would suspect that the particular dynamics of a racing pitlane would conflict with the set of assumptions made in the study you quote. For example - it's been noted that the Indy pitlane is particularly wide. Your profile says that you can program - it would be a straightforward exercise to code up a little simulation of all this.


And now that I've surely sent the population of this board into a deep coma I'd just like to say: "boink" and pull a silly face. Thanks

It's not a statical calculation at all.

It is a simple calculation which shows there can be no more than 600 cars passing through the pitlane per hour.
If you add more pit stops, or if you include that not every car will be able to keep up with those 85 second laps, it just decreases the total number of cars driving through the pitlane per hour, making the situation even more safe.

And a simple observation that 600 cars per hour passing through a pit lane leads to a situation in which it is safe to cross the pit lane.

[Testure]

Originally Posted by Don K

And a simple observation that 600 cars per hour passing through a pit lane leads to a situation in which it is safe to cross the pit lane.

... given the constraints/assumptions/lemmas made in 1) your post and 2) the study in question.

[Gt_R]

The pitlane idea is as wise as a chicane. Which is, not at all.

[John Turner]

Originally Posted by Gt_R

The pitlane idea is as wise as a chicane. Which is, not at all.

No, it's much worse than the chicane option!

[steve_r]

Yes - IMO using the pit lane would have been a dangerous and ridiculous "solution". I still can't quite believe that the FIA suggested this as a serious answer.

[Sodemo]

Particuarly as the Indy pitlane has a very fast and dangerous entry, similar to Barcelona.

[Knowlesy]

The pitlane idea was a ludicrous suggestion. You can't have loads of cars continuosly streaming down the pitlane. yes, there is a limit, but in real terms that is still some speed to be mowing into mechanics. Also, what happens when the Bridgestone cars come in? There could be an accident there as well.

The other idea was to run on the banking at the speed limit. Oh yeah, that's real safe!

Anyone with half a brain cell could see the chicane was the best option. It wasn't necessarily ideal, or fantastic. But it would have been a good compromise.

[Kicking-back]

Originally Posted by knowlesy

Anyone with half a brain cell could see the chicane was the best option.

No - what actually happened was the best solution, given the circumstances.

[Marbot]

And where would they have taken the flag!

Let's imagine that the race had started with the cars using the pitlane.Let's also imagine that MS took out RB at the fuelstop (both are out),both Jordans retired,both Minardis withdrawn.That leaves 14 Michelin runners queuing up each and every lap for the pitlane.Now imagine the last lap when they have to take the flag in the pitlane.....Like pouring treacle into a funnel.

[Don K]

Originally Posted by martyn bott

Let's imagine that the race had started with the cars using the pitlane.

Why on earth would they start using the pit lane?

The start is "beyond" turn 13.
So it would be perfectly safe to start on the grid, and enter the pit lane at the end of lap 1. By that time the 14 cars would be about as wide apart (in time difference) as after a normal lap.

At that moment we would have 14 cars driving through the pit lane.
Which is a lot safer than 14 cars entering the pit lane, making a pit stop and leaving the pit lane -- which is a situation we often have during a race.

After the second lap, the gaps will be approximately twice as big as after the first lap.
So at that time there probably wouldn't be a problem at all.

[Marbot]

Originally Posted by Don K

Why on earth would they start using the pit lane?

I just meant the pit lane option.

What if they'd gone around the track the other way.....Except for the Bridgestone runners....Exciting or what!