Tech insight: The risks and rewards of low drag

With only the chicanes to punctuate the flat-out sections, and the two Lesmos and the Parabolica both long, challenging turns, Monza is Formula 1's fastest circuit.

For most teams, running the low-downforce, low-drag packages used at the Belgian Grand Prix two weeks ago has sufficed. All are running cut-down front wing flaps and flattened rear wings.

But Monza goes a step further in rewarding a low-drag package. With a large disparity between power outputs from the new engines, some are having try harder than others to trim off wing for better top speed.

The limiting factor is how stable the car is under braking. Red Bull team principal Christian Horner went as far as to suggest that his squad is about as low on rear wing as possible without removing the whole thing.

In the cooler conditions, this lack of downforce does mean there is a risk of not putting enough heat into the tyres, especially with the hard-compound Pirellis. So there's a real danger of the tyres dropping out of their working temperature window.

Poor qualifying because of the top speed loss could therefore be offset by better tyre usage in the race.

MERCEDES

Detail development is ongoing for Mercedes, on top of Monza-specific parts.

New for this weekend are the rear wing and the floor edges. Also, the arched trailing edge wing from Spa has been updated to an even lower-drag version.

The wing is shorter front to rear so that the wing-mounting pylons have to be swept back.

The three arches on the flap's trailing edge have been altered to make the edge straight near the wing tips, rather than arching down.

Looking at the floor, the Mercedes now has a Red Bull-style slot ahead of the rear tyres.

Previously, Mercedes ran one large wide slit machined into a metal insert that bolted to the floor around the tyre.

Now, the slot is now L-shaped, a design adopted by McLaren as well as Red Bull.

RED BULL

Again running the tiny rear wing seen at Spa, Red Bull is going with very low downforce.

Even its front wing has been trimmed of its cascade winglets in a bid to reduce drag, such is its lack of outright engine power compared to the Mercedes.

The team's experiments with this configuration in practice clearly proved successful as it kept the same configuration for qualifying.

FERRARI

Not as radical as either of its key rivals, Ferrari ran a simple rear wing and removed the cascade winglets from the front wing.

This loss in drag rewards gives the car with better performance on the straights, as the Ferrari engine is also believed to be down on peak power compared to the Mercedes power unit.

With far less airflow being turned upwards behind the car because off the smaller wings and different ride heights required for the track, Ferrari also made detail changes to the centre of its diffuser.

The middle section is not as steep and therefore lower at its trailing edge. The flaps and vanes also are subtly modified around this area.

McLAREN

Having suffered with a high-drag car that loses out on top speed despite using the Mercedes engine, McLaren was not expected to be on the pace at Monza.

But detail changes and a new Mobil fuel has allowed the car to be competitive so far.

On Friday morning, there was a rare appearance for the aero testing rake. Kevin Magnussen's car was fitted with an array of probes on a moving assembly bolted to the left-hand side of the car.

His first run in Friday morning practice was a single flying lap with a wing that was immediately removed and replaced by the normal front wing.

The Dane's weekend was also disturbed when the cockpit headrest padding came adrift in free practice.

This foam and carbon fibre surround is fitted into the regulatory-shaped cockpit opening.

This is typically secured by lugs in the rear of the headrest locating into matching recesses in the cockpit. It is then fastened to the front of the cockpit near the driver's hands.

In Magnussen's case, the padding must have slipped from its rear mounting and sucked up by the low pressure over the cockpit, necessitating a pit stop to re-secure it.

FORCE INDIA

Along with most teams, Force India brought a Spa-specification rear wing and also a Monza-specific wing.

In its case, the wings are a short chord (front to rear length) and the leading edge being a delta shape.

Being very shallow, the wing required slightly different endplates, without the usual drag reducing louvers in the top front edge of the endplate.

OTHER LOW-DRAG WINGS

For most teams, a rear wing design for Monza can be carried over from season to season.

Despite the aerodynamic regulations banning beam wings for 2014, both Williams and Sauber appeared to re-use old wings from last year, coupled to new endplates to suit the new car.

Marussia had a rare upgrade. Typically, the car is designed with wings that include a range to cover the aero load demands from Monaco to Monza.

But this year, Jules Bianchi ran a lower downforce wing unique to this track.
Caterham, still running its sleek new nose, mated a modified front flap to its front wings.

The adjustable section of flap is shorter to balance the reduced downforce at the back of the car.