1999 BMW 3 Series Sedans: Leading the Way in Safety Engineering
16 November 1998
1999 BMW 3 Series Sedans: Leading the Way in Safety Engineering WOODCLIFF LAKE, N.J., Nov. 13 /PRNewsire/ -- The 1999 BMW 3 Series sedans,
winners of POPULAR SCIENCE Magazine's 1998 "Best of What's New" Award, are
designed not only for optimal performance, design and value, but optimal
safety.
When their ancestor, the BMW 1600-2 sports sedan, was introduced in 1966,
BMW was already engineering its automobiles for safety. Rollcage construction
and energy-absorbing crush zones were engineered right from the start. Padded
dashboards were standard in 1968 and 3-point front safety belts were added in
1969. Today, however, design for safety is fundamental and all encompassing,
and it is a given that a new vehicle generation will offer advances in safety
over its predecessor, no matter how good the predecessor.
So it is with these new 1999 models, successors to the 1998 318i and 328i
sedans. Their predecessors already incorporated many safety features,
including but not limited to:
-- Antilock braking system
-- Full-capability traction control system
-- Automatic front safety-belt tensioners and force limiters
-- Dual front- and side-impact airbag Supplementary Restraint System
-- Dual-threshold deployment system for airbags and front safety belts.
The 1999 3 Series sedans set a new standard for this class, introducing
significant new active safety technology, while putting these smaller models
essentially on the same level as the larger BMW models with regard to passive
safety.
Active-Saftey Technology and Features
BMW's All Season Traction is a full-capability, all-speed traction control
system. On slippery roads, for example, AST helps facilitate stable
acceleration by modulating engine power and wheel brakes to best utilize
available road traction. It even helps on deceleration: If the driver lifts
off the throttle and the drive wheels thus begin to break loose on ice or
snow, it adjusts engine speed to help avoid a skid. AST was standard on all
1998 BMW models, and continues on the new 1999 3 Series sedans.
In addition to standard antilock braking system (ABS) with upgraded
4-wheel ventilated disc brakes, the '99 323i and 328i sedans have a further
stability-enhancing system, which is a BMW exclusive; Cornering Brake Control
(CBC). Experience has taught that in a hard turn, applying the brakes can
upset a vehicle's stability. A light brake application tends to make the
car's nose tuck in (less understeer/more oversteer); a harder application may
nudge the vehicle off-course toward the outside of the curve (more
understeer). CBC counteracts these tendencies by modulating brake action at
individual wheels in a precise way; for instance, it can cause brake pressure
at the outside front wheel to build up more rapidly than at the other wheels.
CBC first appeared in the 1997 BMW 528i.
Xenon headlights, first introduced on the top-of-the-line BMW 750iL, will
be optionally available on these new 3 Series models, offering a standard of
night visibility previously unavailable in this class and making these new
BMWs the lowest-priced cars to offer this technology.
NEW ON THE PASSIVE-SAFETY FRONT
Front-seat side-impact airbags became standard in the 3 Series in 1998; in
the 1999 3 Series sedans, rear-seat side-impact airbags also become available,
as a moderately priced option. But side airbags are only part of the new
sedans' side-impact protection, for both models also incorporate as standard
BMW's Head Protection System.
Currently offered only by BMW, the HPS anchors an inflatable tubular
restraint inside the interior trim of the windshield pillar and above the
front door on each side of the car. In a severe side impact, a deployment
system inflates the tube; it pops out of the trim to form a straight tube 5.1
inches in diameter and stretched in a line from windshield pillar to roof.
This is where the head of an occupant -- of large or small stature -- could
strike the side of the car. Presently, only BMW is offering HPS; it is also
standard in the 5 and 7 Series.
Adopting another feature from the larger BMW models, the new sedans
incorporate the conceptually simple, yet supremely logical interlocking door
anchoring system. In each door is a diagonal aluminum reinforcing beam, at
whose ends are "hooks" that grab into the fixed side structure in case of
severe deformation. This arrangement helps tie the doors and main structure
together to offer a high degree of structural resistance to side impacts.
Another exclusive BMW safety feature, introduced for 1998 on the 5 and 7
Series and now part of these new 3 Series sedans as well, is the innovative
Battery Safety Terminal. In a severe accident impact, a tiny pyrotechnic
charge breaks the connection between the battery and starter cable. This
high-voltage connection is thus removed as a possible cause of a post-crash
fire, yet lower-voltage circuits remain intact; In every current BMW model,
for instance, after a major impact the doors unlock electrically and the 4-way
hazard flashers and the interior lights are automatically switched on.
Furthermore, all current BMW models, including these new sedans,
incorporate the Dual-Threshold Deployment System, which deploys the airbags
and safety-belt tensioners according to impact severity, whether or not the
occupant is belted, and whether or not the front passenger seat is occupied.
Thus, for example, in a relatively mild frontal impact, a belted occupant's
safety belt could be tensioned but the front-impact airbag not deployed,
whereas if the occupant were not belted the airbag would deploy.
As part of the new models' overall system for occupant protection in
frontal impacts, their steering column is newly conceived and engineered.
Aluminum and magnesium are employed to achieve optimum energy management
characteristics without undue weight, and the upper and lower portions are
designed for better "decoupling" of their movements in a crash.
The new models -- 328i sedan and 323i sedan, both powered by new
6-cylinder engines -- will be the first models of this new generation,
arriving in showrooms of BMW Centers across the U.S. late this summer. Other
current models of the 3 Series -- coupe and convertible for example -- will
continue to be produced alongside the new sedans until their successors are
ready to be rolled-out in the future.
