How F1 Works: Drag Reduction System (DRS)

TRP

We hope that all of you guys have had a good break from Formula 1 and are keen for some action this weekend. For those who do have a liking for sporting events outside of F1, there wouldn’t have been a dry spell so to speak. Anyways, we’re still a few days from actual on-track action and have just enough time to throw in some technical tit-bits, just so that it whets your appetite for this weekend. This little piece covers a technical aspect of Formula 1 racing that has taken centre stage in the course of this season along with the nasty Pirellis- Drag Reduction System (DRS). It has had its fair share of limelight in the 2012 season making an impact with the opening race itself at Melbourne.

This is the first article in the series of many more which will be published every now and then under the title – “How F1 Works” and will give little insights into the technical aspects of the sport. As for this one, we have made an effort to keep it simple and give you just the essence of what it amounts to on the track. The mind-wrenching intricacies are better left to the manufacturers and we want this article to just make for an enjoyable read. Now, let’s get down to business.

The DRS is essentially a movable aerodynamic component on an F1 racing car which, as the name suggests, reduces drag and facilitates overtaking. It was introduced in the 2011 season by the FIA as Driver adjustable bodywork wherein the incidence of the ‘rearmost and uppermost’ closed section of the bodywork behind the rear-wheel centerline can be varied while the car is in motion. To put it in a form which is more palatable, it is an adjustable flap on the rear wing of the car that responds to driver’s commands. Now, like all movable components of an F1 machinery, the system relies on hydraulic lines and actuators to control the flap. The current bunch of cars uses the E024 servo valves manufactured by Moog that are driven by electronic units that receive signals from the cockpit. We’ll leave the installation part there and refrain from going into further details that are the headache of the teams.

How it Functions

When the driver deploys the moveable rear wing, the adjustable flap is lifted about 50mm clear of the fixed plane of the wing so that it lies flatter to the air. The altered wing profile reduces the drag on the wing by about 5% and also results in lesser downforce. Now it’s easy to conjecture that in sections of the track with very low lateral forces such as the straights (where grip is not an issue), lower downforce coupled with the reduction in drag enables faster acceleration and a higher top speed. The flap is lifted about the trailing edge so that it falls into a default position (original high downforce one) in case of failure.

The setup, as intended by FIA, enables a pursuing car to boost its speed relative to the car in front and hence make an overtaking maneuver. Now if the entire field was to use DRS on their cars together there won’t be any (overtaking)! Also, in a certain case with a faster car following a slower one around a corner, the leader would be able to deploy the DRS, fractions of a second early and run away with an advantage even as the car behind corners without the DRS in the want of grip. This is where the FIA came in with its share of control over the matter- it defined a concept of a car being ‘close enough’ to the car in front.

Two lines, namely the Detection Line and the Activation Line are clearly marked on the track just ahead of a corner leading into a straight. When a car pursuing another is detected within a second of the car it is following (measured using the timing loops on track’s surface), it gets a signal flashing on the steering reading “DRS Active” as it hits the activation point. After using all the grip to get around the corner, the driver can use his active rear wing to sprint down the straight, dive alongside the car in front and finally make the move just ahead of the next corner when he is effectively 10-12 kmph faster. The car remains armed until the flap is released or brakes are used.

As we have already mentioned, the effectiveness lies in the way the technology has been deftly handled by FIA. But there are certain aspects that may need tweaks for an even enhanced performance. For instance, the current clearance of about 50mm is fixed in the regulations irrespective of the track. In circuits like Monza where the original setup is that of medium to low downforce, or in contrast, circuits like Monaco where straights are far and few, the advantage may be negligible and in cases such as these it would not be a bad ploy to allow more pronounced flap movement say up to 10 degrees as opposed to the 4 degrees fixed currently. We believe the governing body must be keenly observing the way DRS performs on various tracks and the issues mentioned above might just be addressed some time in the future. All said and done, it has given the sport and its viewers more overtaking moves and, along with the Pirellis, has been the major proponent in making this season a gem.