Interest in driver comfort spreads to P&D vehicles.

No two drivers are precisely the same size. Yet many millions of them spend their careers driving in standard size seats that don't provide the most comfortable working environments. After all, they can't just get up and stretch their legs for relief. Which raises an important question: How are seat makers refining the driver's seat so it can be a tool that fleets can depend on to help prevent drivers from getting up and walking to a competitor that offers better working conditions?

In theory, the ideal seat should free the driver from the strain of having to stay seated while the vehicle is shifting about during the course of normal operation, allowing full concentration on the serious business of driving. Seats should not move from side to side, and the driver should not have to cling to the wheel to maintain his balance. However, the kind of seat that makes the driver so relaxed that he gets drowsy is also not desirable. The ideal seat promotes relaxation and concentration simultaneously.

The kind of R&D work that has created advanced seating for the racing and passenger car industries has led to spin-off applications for the trucking sector.

Recaro seats, German-engineered for Porsche, are now assembled in the U.S. Standard features of Recaro's AM 31 commercial seating system include an electronically activated air suspension system, which automatically adjusts to the weight of the driver, and a totally independent height adjustment system.

By separating these functions, the driver can position himself at the correct height without compromising the effect of the suspension. This overcomes a problem some air suspension systems encounter at either end of the scale: They top out or bottom out, losing their bounce.

Isringhausen's U.S. division is introducing a new seat that uses advanced suspension technology. The 6800 offers a unique air height adjust combined with automatic self-leveling air suspension. This combination automatically puts the seat in the mid-ride position, regardless of the operator's weight. The mid-ride position is optimal because it assures adequate suspension travel distance for the seat in up or down direction.

Knoedler Manufacturers will launch the new 9800 Air Chief series this summer, incorporating various design features of its 9200 Air Chief and premium 9400 Air Lumbar products into a "scissor-type" suspension system. By using a bolt-on riser, the 9800 can fit virtually any application, including those with restricted headroom.

Bostrom Seating has launched its Talladega 900 Series. The Talladega comes in five designs, with different models for medium-duty/city trucks and cabover/conventional use. Models Air-910 and Air-905 SC/LSC feature self-contained 12-volt air compressors to provide the comfort of air suspension for medium-duty trucks and other vehicles without engine-driven compressors or air brakes.

Also part of the Talladega series is the Baja, an economy seat designed specifically for vehicles making short runs on quick deliveries. Available in two models -- a low-profile 4-in. rise zone and a high-profile 6-in. rise zone -- Baja seats are equipped with Bostrom scissor-type suspensions and come with a 3-yr./300,000-mi. warranty.

National Seating is continuing to improve its Cush-N-Aire II . The standard Cush-N-Aire model includes contoured cushions; 7-in. fore and aft slide; front-cushion adjustment; recline positions ranging from 6 to 23 deg.; power air lumbar; rear-cushion adjustment; and chugger snubber. Custom and premium models are also available.

Designed by Sears Manufacturing Co., the new Voyager Series (formerly made under the name Dura-Form) offers longhaul drivers wider, deeper backrests for full shoulder support and softer, thicker seat cushions for added comfort. Rocker switches, which are conveniently located below the edge of the seat cushion, provide easy adjustment of the seat's suspension and air lumbar support system.

Seats Inc. has introduced a Summit air suspension seat that features ergonomically clustered air, electric, and manual controls, as well as a swing link fore and aft called a Glider-a-lator. In addition, the seat has a 21-in. seat cushion with flexible comfort zone for maximum tailbone support, and a 4-way adjustable cushion angle and height adjustment for upper thigh and pelvis support.

Comfort Ride has extended the availability of its LP line, until now only available on Class 7 and 8 vehicles, to Class 6 trucks. A three-point pneumatic strut suspension system creates "a floating experience," according to the manufacturer. Other features include maintenance-free technology utilizing hardened crown roller bearing for the smoothest snubber in the industry. Air-assisted infinitely adjustable isolator gives 17/8 in. of free travel with forward or rearward locking.