Wednesday, April 29, 2009

What you may notice during F1 practice


When you watch Formula One drivers practice, keep a couple of things in mind.
First, being fastest isn’t everything. Although practice times are issued after each session, these times aren’t necessarily a definitive indicator of what shape every car is in. All teams work through their programmes in different ways and with different aims in mind. It’s often not until the qualifying sessions or the race that you see the true picture unfold as everyone tries to put together their best combination of factors. Treat the practice times as only a very loose indicator of competitiveness.
Second, some people get extra sessions. If you get to the track very early on Friday morning – well before the first official practice session – you’ll see some teams lapping the track while others never venture out and you may wonder why everyone isn’t out trying to beat the band. As a way of helping smaller teams cut costs, the FIA, the Formula One governing body, introduced a policy at the beginning of 2003 stating that a team could opt for one of the following:
  • To have unlimited test days.
  • To test up to a maximum of 20 car days (10 days for two cars or 20 days for one car) and be allowed to test for two hours on the Friday morning of each Grand Prix meeting.
The latter option is the cheaper one, but it has other advantages as well. It gives the teams a head-start in choosing the ideal tyre, in establishing fuel consumption figures, and in coming up with a good set-up. In terms of the work dedicated to the race weekend, by the time practice begins, they’re already one step ahead of those teams who can’t do the Friday test because they’ve opted for an unlimited number of test days outside of the Grand Prix weekends. The benefit of unlimited testing is that the total number of hours available for testing new developments and innovations is far greater. This particularly benefits the bigger teams who have more of such things to test than their smaller rivals.

Finding optimum fuelling in Formula One practices


The practice sessions are also used to verify fuel consumption and the precise relationship between fuel loads and lap times. These vary from track to track. A circuit with lots of accelerating in the lower gears and lots of hard braking makes for far less fuel efficiency than a track that flows more. But the engineers need to know precise figures so that no more fuel – and therefore weight – need be put in the cars than is absolutely necessary. The car tends to get quicker as its fuel load drops, but again, the engineers need to know by exactly how much in order to determine whether the extra performance brought by a low fuel load buys enough time to make an extra pit stop.
Often, the performance of the tyres degrades as the performance of the car improves because of its lower fuel load. At some crossover point, however, the car begins to lose more lap time from degrading tyres than it can find from lower weight. Practice gives the engineers and drivers a chance to establish where this point is. Again, this knowledge has a significant impact on the race strategy the team chooses.

Choosing tyres in Formula One Practices


The practice sessions also give the teams valuable information on the respective behaviour of the two different compounds of tyres that they have to choose from before Saturday qualifying. The sessions give them information on the differing wear rates of each tyre and also the difference in their performance pattern.
Practice sessions allow teams to see how the performance of each type of tyre changes over a number of laps. A softer compound is usually quicker initially, and invariably quicker from new on a qualifying lap. But it also tends to wear out more quickly than a harder tyre. Softer compound tyres also have a greater tendency to grain, a phenomenon where small tears appear on the edges of the shoulder, spreading across the whole width of the tyre, giving less grip until they stabilise. With less grip, the cars can’t go as fast as they would otherwise. Graining can last for up to 10 laps and, although the softer tyres may then be quicker than the hard tyres, after that the speed difference may not be enough to overcome the time lost because of the graining. Practice gives the engineers and drivers a feel for how this behaviour is panning out. Even though the data may tell a clear story on tyre choice, a driver may still be influenced by how each compound “feels”. A softer compound gives more grip and, therefore (in theory at least) offers a better lap time, but it also tends to feel less stable because its tread moves around more under cornering load. Occasionally a driver may find he is actually quicker on the harder compound despite its lower grip levels simply because it instils him with the confidence to push harder than when he’s using the soft compound. Practice gives the driver the chance to get used to the more squirmish behaviour of the softer tyre, or it enables him to quickly discard it and concentrate on setting the car up around the harder tyre.

Monday, March 30, 2009

Establishing F1 practice set-up


The main purpose of practice sessions is to enable the teams and drivers to find the optimum set-ups (suspension and aerodynamic settings) for their cars. These set-ups vary according to whether the team is preparing for the optimum one-lap of Friday qualifying or the one-lap-plus-a-race of Saturday and Sunday. They also vary according to the type of tyre the driver and his engineers choose.
Most of the time in Friday practice is spent pin-pointing the ideal balance for one-lap qualifying on Friday afternoon. With very little fuel on board and the need only to do one flying lap, the set up will be very different from that needed for Saturday qualifying and the race – when the cars will run with enough fuel for the race’s first stint. During Friday practice the driver looks for a set-up that gives him instant response into the corners for ultimate onelap speed. During the Saturday practice the goal is more about finding a good level of handling consistency from lap to lap. A car racing on Sunday with a Friday set up would quickly become undriveable.

What the drivers get out of practice


There’s an hour of practice on Friday before the first qualifying session and another one and a half hours on Saturday, before the second qualifying session. The drivers can take to the track whenever they want within these practice sessions and do as many or as few laps as they choose.
You may think – as the word practice implies – that the idea is for the drivers to learn how to drive the track but in truth, all drivers are able to do that pretty much immediately. Or you may think that the idea is just for the cars to go round and round for the benefit of the crowd as a build-up to the big race – and you wouldn’t be entirely wrong. But it’s way more complex than that. Qualifying and race strategies are very much based on the information established during the practice sessions. Although general testing can give a team some of this information, such testing is permitted only at certain tracks. Furthermore, the weather conditions on the day have a serious impact on tyre performance and the general behaviour of the car. From the practice sessions, drivers and their teams get the information they need to set up the cars, choose the tyres they’ll use, and decide on a fuelling strategy.

What the rookie needs to know


The information required by the rookie as he makes his track walk or ride is rather more basic than the info that experienced drivers seek. Obviously, a rookie needs to know where the track goes, and he also needs to get a feel for which lines to take for a corner or sequence of bends. The fastest line through a corner is essentially the shortest distance between the points of entry and apex. Getting a sight line when stationary at the beginning corner is often a good way of establishing where the cornering line is if the corner is at all complex. Picking out visual markers – a trackside advertising banner, for example –that equate to the turn-in point can be very useful. The perspective a driver gets from inside the cockpit, just a few centimetres above the ground is often inadequate for picking out fine detail. Similarly, details of the track’s surface or its camber – or the parts of the track across which streams run when it’s wet – cannot really be gleaned when travelling at high speed in the car. But a driver who already knows what he’s looking for because he’s walked the track has a big advantage that he couldn’t have obtained otherwise.
Telemetry can be a great aid for a driver learning a circuit – but obviously only after he’s driven the track. He can then look at his own data-logging traces of steering and brake and throttle input and compare them to his team mate’s. He can try a variety of approaches on a corner he’s not sure of and then compare telemetry with lap times to see which approach works best. He can then apply the lessons learned next time he takes to the track. These are Formula One drivers. Learning a track is not, in the general scheme of things, all that difficult for them. Juan Pablo Montoya, who on his Formula One rookie year of 2001 scored three pole positions and one Grand Prix win, reckoned he would know 90 per cent of what he would ever know about a new track after his first three laps of it. Drivers that only get themselves on the pace after much practice and long and detailed study probably haven’t got what it takes to be top Formula One contenders.

Saturday, February 28, 2009

Sussing out the details


When an experienced and successful driver, such as Michael Schumacher, travels around a track – even one he’s driven many times before – he isn’t looking at how best to drive the track, he’s investigating any small changes that may have been made since last time he was here. He wants to know stuff like
  • Where the protective barriers are placed
  • How many layers of tyres are protecting key spots
  • Whether the track surface has changed anywhere, and if it has, how the grip levels now compare to the grip levels before
  • How deep the gravel traps are (some gravel traps literally beach the car if you go off into them, others can be driven gingerly across)
  • Where the access roads for the rescue vehicles are. (These roads can double up as a useful route back onto the track if you go off.)
  • Where the marshal posts are. (At each marshal post, a circuit worker is available on a motorcycle to give a driver a lift back to the pits should he need it.)
By observing key details of the track, experienced drivers gain important information that they can use to their advantage during the race. Take Michael Schumacher, for example. Few drivers equal his skill and knowledge of the various tracks, yet he doesn’t rest on his laurels. He susses out the details of each track he races on and uses these little details to hone his approach to the track. You’ll often see Schumacher in the practices pushing like crazy through specific corners, establishing where the absolute limit is. He can do this safe in the knowledge that he’s checked out the gravel trap and knows that, if he goes off, he’s not going to lose the rest of the session because his car got stuck there. He only pushes in this way on those corners where he knows he can rejoin the track.