Overview: Aston Martin Rapide

Aston Martin’s five-door Rapide first appeared in 2006 as a concept car at the Detroit Auto Show. Response to the show car was such that it was almost immediately approved for development; something over two years and 50 prototypes later, the Rapide was ready for production. The new car was developed using Aston Martin’s ‘V/H Architecture’ platform, which already forms the basis of the Company’s DBS, DB9 and Vantage.

Aston Martin Rapide.

The production Rapide made its first appearance at the Frankfurt show last autumn. It’s built in a new 23,000m² manufacturing facility at Graz in Austria, and it is the Company’s first car with four passenger doors; each rear door, like the front ones, leads to a properly shaped individual seat.

The tailgate is large — daringly so, considering the effect that a big hole has on the torsional rigidity of a bodyshell. Open that big rear hatch and you have access to enough space to house four people’s overnight bags or — at a pinch — golf clubs. Beware, though: there’s no load cover, and the rear seats don’t meet in the middle. A divider can be raised or lowered to create a separate area accessible from the back seats, but it’s not intended to halt large, heavy objects during hard braking.

The rear seat-backs fold down at the touch of a button, but the surface they present is rather too expensive, and rather too irregular, for any sort of hard load. Needless to say, the front seats don’t meet in the middle either.

The passenger doors open on an axis inclined 12 degrees to the vertical in an effort to avoid embarrassing incidents with curbstones. Aston Martin calls them ‘swan wing’. Side glass is frameless and laminated. At speed, the side windows are automatically powered further into their upper seals to minimise wind noise.

Aston Martin has set out to improve rear passengers’ view of the road ahead by profiling of the B-pillars, but it’s a token effort: the rear seats are mounted low, and the tombstone front seat-backs will always define the view ahead.

All is not lost, though: you can specify a rear entertainment system as an optional extra. Two LCD screens are integrated into the backs of the front seat head-restraints, and a six-DVD multi-changer is mounted in the boot. Sound is delivered by way of wireless headphones or through the standard Bang & Olufsen Beosound Rapide audio system. The two screens can be operated together or independently. Bizarrely, an infra-red remote control is supplied.

The Beosound Rapide system has an output of 1000W. One kilowatt. That’s enough for a Pink Floyd concert. There are 15 speakers.

Luggage space is adquate for four people’s squashy bags. Rear seat trim is expensive and unprotected. Beware of big gap between rear seats.

The Danish audio company’s ‘Tonmeisters’ worked with Aston Martin’s acoustic engineers during the entire development of the Rapide to create a ‘soundstage’ — a soundscape whose source cannot easily be traced to an individual speaker or speakers.

Powering up the B&O system, there’s sense of hi-tech theatre as two acoustic lenses rise silently out of the dashboard. Acoustic lens technology enables a 180-degree horizontal dispersion of high frequencies, minimising the loss of — for example — sibilants, and gives listeners an improved sense of space. Acoustic lenses also allow sound to be focused within the car according to how many occupants are aboard and where they’re seated. In ‘Auto’ mode, the system uses sensors on the seatbelts to adjust the soundstage for the benefit of all occupants equally. There are also manual override options, which focus the sound for the driver, the two front occupants, the two rear passengers, or all four occupants.

A microphone behind the rear-view mirror continually monitors background noise, and the sound system’s volume is automatically adjusted to compensate.

Folding rear seat-backs would be more useful if they had tougher trim.

Rear passengers have their own individual heating and air conditioning system, independent of that used by the front occupants, controlled by a rotary dial with a digital temperature display. There are air vents at face-level and in the footwells. The rear climate control system can also be operated from the front.

Aston Martin is the latest of many manufacturers to abandon the lever-operated hand-brake in favour of an electric device, allowing a large centre console. In the case of the Rapide, the console extends between the rear seats and includes lidded storage cubbies.

Rear seats are snug. Centre console provides cup-holders, storage and air-vents with temperature control.

Eight airbags are fitted in the cabin. Restraint sensors around the car determine which bags to deploy, and to what extent, in the event of an accident.

Drivetrain & architecture

Motive power is supplied by Aston Martin’s 6.0-litre V12, built by hand at Köln in Germany. Outputs are 477PS and 600Nm; the unit drives through a six-speed epicyclic automatic transmission, with magnesium paddles mounted on the steering column for manual gear-changing. The transaxle is the same unit that’s used on the DB9, but remapped to take account of the Rapide’s extra weight.

The system also includes a ‘Sport’ mode, activated by a button on the centre console. This can be called up whether the gearbox is being controlled manually or automatically. A more sporting gear-change map is used, and gear-changes feel sharper. The matching of engine speed on down-changes is also more aggressive. In full automatic mode, upshifts occur at higher speeds.

The transmission works in the same way as it does on the DB9. The drive mode — Park, Reverse, Neutral and Drive — is selected by way of controls on the facia. In Drive mode, pulling either of the magnesium alloy paddles mounted on the steering column will activate Touchtronic (manual) mode, allowing the driver to change gear using the paddles. Drive (automatic) mode can be selected at any time by pressing the ‘D’ control on the centre console.

During the Rapide’s two-year gestation, the drivetrain’s performance and reliability in hot weather were tested in Death Valley and Kuwait, with prototypes exposed to temperatures of 50°C and above. Low temperature tests were carried out in Sweden and in a cold testing chamber, with temperatures around -40°C being the norm.

High speed testing was conducted at the Nardo proving ground in Italy, while handling dynamics were honed at the Nürburgring, with prototypes run for 8000km on the Nordschleife.

Although the new Aston has four passenger doors, the Company has tried hard to keep its dynamics up to the standard of its two-door siblings. There are potentially two significant problems: the torsional rigidity of the bodyshell, and the height.

The build had to be kept low to control the centre of gravity. But four people must fit inside, and this demands a more upright seating position: the Rapide is 90mm taller than the DB9. Extra width (and a wider track) mitigate the higher stance.

The Rapide is a long car, too, at over five metres. Compared with a DB9, the wheelbase has grown by 244mm, overall length by 309mm. This stretch in length means a stretch in the polar moment: good for straight line stability on long journeys, but not for cross-country agility. That’s not to say the Rapide is a bus, of course: the engine is mounted in a front-mid position, largely behind the front axle line, and it drives through a rear-mounted transaxle. Engine and transmission are connected by an alloy torque tube with a carbon-fibre prop-shaft running inside it.

The Rapide is a large car with four passenger doors and a large rear hatch aperture. Good structural rigidity is hard to achieve with a big five-door bodyshell, but is essential for good handling. The result of Aston Martin’s efforts is a torsional rigidity value of 28,000Nm/degree for the ‘V/H tub’, which is the structural core of the bodyshell. This is actually better than the DB9’s 27,500Nm/degree.

Aston Martin’s ‘Vertical / Horizontal’ or ‘V/H’ architecture is the basis for the Company’s current cars. It’s a platform technology derived from aerospace practice, using aluminium elements which are bonded together rather than being welded. The result is a good ratio of torsional rigidity to weight. Jaguar used a similar construction technique to good effect with its new XJ bodyshell.

All of the Rapide’s body panels are new. The front wings are formed from composite materials, while the doors and roof are pressed aluminium. The rear quarter panels are steel.

With a front-mid engine and a rear transaxle, the Rapide’s weight distribution is perfect — 49:51, or pretty much 50:50 with a driver aboard. So the car starts well balanced. Its 20" wheels are shod with Bridgestone Potenza S001 tyres; the Rapide’s Potenzas have slightly taller sidewalls than standard to improve refinement.

For the first time on an Aston Martin, the new car features dual-cast brake discs. The discs are made from two materials — cast iron and aluminium. This is a relatively new technique, providing a lower unsprung mass: each disc is 15-20 per cent. lighter than a standard cast iron disc. Using both cast iron and aluminium takes advantage of the heat resistance provided by cast iron and the lighter weight of aluminium. They also promise superior braking performance, reduced corrosion and less wear.

The Rapide’s braking system features a new control unit that delivers more discreet interventions and provides improved functionality for existing features. It also incorporates a new Hydraulic Brake Assist (HBA) system: this identifies — from the speed at which the brake pedal is pressed — when the driver wants maximum braking performance, and automatically boosts the brake pressure up to the ABS control threshold for as long as the driver keeps the brake pedal pressed down.

On top of the brake assist system, there are all the usual electronic driving aids.

Aston Martin’s Adaptive Damping System (ADS) makes an appearance. First seen on the DBS, it uses two valves to set the dampers to any of five different settings according to driving conditions, providing ‘live’ adjustment of the car’s ride and handling. The driver can manually select a ‘Sport’ mode, which sets the dampers to their firmest setting.

The three-stage Dynamic Stability Control (DSC) system allows the driver to tailor the level of electronic intervention according to the circumstances. In its default mode, the system is set to limit tyre slip in difficult conditions and provide the maximum amount of security possible without being intrusive. Holding the DSC button for five seconds engages Track Mode, which delays the electronic intervention, allowing the driver to feel a little of the car’s limits. Holding the button for a further five seconds will disengage the system completely.

Miscellaneous specifications

Body

  • Extruded bonded aluminium
  • Aluminium, magnesium alloy and composite body
  • Extruded aluminium side impact beams in doors
  • Single bi-xenon headlamps with integrated LED side-lights and direction indicators
  • LED rear lamps and side repeaters

Suspension

  • Front: Independent, double wishbones incorporating anti-dive geometry, coil springs, anti-roll bar and monotube adaptive dampers
  • Rear: Independent, double wishbones with anti-squat and anti-lift geometry, coil springs, anti-roll bar and monotube adaptive dampers
  • Adaptive Damping System (ADS)

Brakes

  • Front: Dual-cast brake discs, 390mm diameter with six-piston calipers
  • Rear: Dual-cast brake discs, 360mm diameter with four-piston calipers
  • Dynamic Stability Control (DSC)
  • Anti-lock braking system (ABS)
  • Electronic Brakeforce Distribution (EBD)
  • Emergency Brake Assist (EBA)
  • Traction Control
  • Hydraulic Brake Assist (HBA)
  • Positive Torque Control (PTC)
  • Electronic Park Brake (EPB)
Aston Martin
Rapide
Aston Martin
DB9
Porsche
Panamera S
Body type 4-door coupé 2-door coupé 4-door coupé
Cylinders 12V 12V 8V
Valves 4 4 4
Bore/stroke 89.0/79.5 89.0/79.5 96.0/83.0
Swept volume 5935cc 5935cc 4806cc
Compression
ratio
10.9:1 10.9:1 12.5:1
PS/rpm 477/6000 477/6000 400/6500
Nm/rpm 600/5000 600/5000 500/3500
Maximum speed 188 190 175
0-100km/h 5.3s 4.6s 5.4s
Urban MPG (l/100km) 12.5
(22.6)
11.7
(24.1)
17.6
(16.0)
Combined MPG
(l/100km)
19.0
(14.9)
18.2
(15.6)
26.1
(10.8)
CO2 g/km 355 345 253
Transmission A6 A6 (M6) A7 (M6)
Driven wheels Rear Rear Rear
Fuel tank 90.5l 80l 80l
Length 5019 4710 4970
Width 1929 1875 1931
Height 1360 1270 1418
Wheelbase 2989 2745 2920
Kerb mass 1990 1800 † 1800
Wheels: front
Wheels: rear
20"
20"
8.5Jx19"
9.5Jx19"
8.0Jx18"
9.0Jx18"
Tyres 245/40
295/35
235/40
275/35
245/50
275/45
† 1760kg with manual transmission.

Aston Martin engine plant, Cologne

Aston Martin officially opened its dedicated engine plant at Cologne, Germany, on 28 October, 2004. It was the Company’s first (and remains its only) purpose-built engine production facility. All engines for the Aston Martin range — DBS, DB9, V8 Vantage and V12 Vantage — are produced at the Cologne facility.

The opening of the new plant underlined Aston Martin’s serious intentions for growth at a time when the British marque was under Ford ownership. (Although now independent of Ford, the Company’s ambitions are clearly undiminished.) The Aston Martin engine facility is a part of Ford’s Niehl engine plant, but has always been equipped to work solely on Aston Martin engines. The building carries the Aston Martin corporate identity.

The Aston Martin engine plant has a 12,500m³ production hall, which has sufficient capacity to support Aston Martin’s current and expected future needs. The facility broadly comprises four distinct areas: one to machine engine cylinder blocks, one to machine cylinder heads, one to assemble all engine components, and an area for goods received and engine shipment. All engine testing is completed during the assembly process.

The facility is capable of machining and assembling V8 and V12 engines simultaneously. Each technician will build a complete engine from start to finish; at full production, more than 30 technicians will be building engines.

Run in compliance with ISO 14001 environmental regulations, the facility also benefits from state-of-the-art features including an adaptive lighting system that automatically adjusts according to the level of available daylight. Additionally, all of the equipment used within the facility has been specified not to exceed a noise level of 77db(A).

Aston Martin engine under construction at dedicated facility in Cologne, Germany.
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