This week, across the road from the factory at Silverstone Circuit, Midland F1 has been undertaking an exclusive test in private. Part of this week's test programme involved the team undertaking straight line test runs, in addition to "running in circles" around the Northamptonshire circuit. Ever wondered why teams do this kind of testing? Technical Director James Key was kind enough to provide the answers.

Generally why do teams elect to run exclusive straight line tests as opposed to using the full circuit?
James Key: Full circuit testing tends to be for quantifying performance levels and developments, as well as producing a realistic environment for reliability running. If a particular system is required to be measured or studied in detail, the number of variables during normal track running often do make it possible to make clear conclusions from the data acquired. Straight line running is a very controlled form of track testing which allows repeatable measurements to be taken from one outing, minimising the effects of other variables. A typical example is full scale aero testing on track, which requires consistent weather conditions, constant sensor monitoring and a lot of data processing.

What were Midland F1's aims at the test this week?
JK: There were a number of aims for this week's testing. The first day of testing was normal track running, during which we were evaluating some new mechanical components, a number of aero updates for San Marino and tyre testing with Bridgestone. On the second day, we will undertake dedicated control system testing.

How much of this test was just the progression of the teams development programme, and how much of it was specific to the next race at San Marino?
JK: Much of this test is a progression, some of which has come off the back of the three fly-away races we have just covered. However, all the parts that are being tested are intended to run from San Marino onwards.

Are there any differences between the way the team prepares and sets up for this kind of test session?
JK: For the dedicated straight line testing, there are a number of differences. Typically, these tests are for data acquisition, so additional sensors and data processing is required. Setup is maintained at a "nominal" level mechanically, while any test parts or methods/system to be run would be cycled through and compared to baseline runs, which are regularly undertaken through the day.

How is data collected from straight line tests?
JK: As mentioned, straight line running is primarily about data acquisition and less about driver feedback, although this always remains useful. Depending on the nature of the test and what we are attempting to prove at the time, data will be collected in many different ways. It is important to understand all the factors which could affect the test results, and therefore additional sensors (in some cases specialised sensors or equipment which would only run for specific test requirements) and data processing methods will always be required.

The majority of data acquisition will be car based. However, in some cases, measurements of ambient conditions, wind direction, etc. will be monitored closely for each outing to ensure that any outside factors which will affect the data can be compensated for. A significant amount of data processing tends to take place after the event is complete. A straight line or similarly-controlled test will normally allow the team to learn a great deal about one particular aspect of the car's behaviour, far more than can be gained from normal track running. The knowledge gained is then fed into further car development.

Do the drivers have to change their preparation and driving style in order to gain the benefits of straight line tests?

JK: Yes. To be honest, straight line testing can be fairly boring for the drivers, as they are less involved with the work being carried out and running is very repetitive. Having said that, much depends on the type of testing being carried out. For aero testing, there is little that a driver can feedback or influence. During control systems testing, however, the driver is more involved. In all cases, the driver will have to be very consistent, so there is a fair amount of importance to the "driving style" employed. Similarly, there may be some driver "training" required during such tests for new control system developments, or modifying the way a certain manoeuvre is carried out. In this respect, the tests can be useful to the driver, in that he may be able to carry over some of what is covered to normal track running.