New Vehicle Seats Improve Troop Survivability in Blast Events
These advanced survivability seats use a stroking mechanism built into the seat’s design to direct energy in upward “lift-off” movements and downward “slam-down” events. A self-reset feature within the stroking mechanism assists with energy-absorption. Combined, these elements provide protection for occupants from potential neck, spinal and other injuries commonly associated with roadside bomb explosions.
Military vehicle seats that enhance survivability are quickly becoming a more prominent option for vehicles that don’t have add-on armor or up-armored protection. As budget constraints continue, customers are now turning their attention to implementing survivability upgrades as a less costly way to provide an added layer of occupant protection.
Some of the most advanced seats are found in the Army’s Bradley fighting vehicle and the Caiman mine-resistant ambush protected (MRAP) truck.
“Survivability seats provide an additional layer of occupant protection that a military ground vehicle can’t accomplish,” said Curt Parsons, chief engineer and engineering fellow at BAE Systems Protection Systems. “Ground vehicles, like the Bradley and MRAP, provide occupants with significant protection, but survivability seats take that protection one step further, aiding in the protection of an occupant’s spine and neck, among other injuries during crashes and explosions.”
While survivability is the number-one concern in seating systems, there are several other features accounted for during seat design. Interior fit, ingress and egress, functionality, and comfort all play critical roles throughout the entire design process.
Next to survivability, interior fit is the most important element. Interior areas of a vehicle’s cab are often confined, making space utilization essential.
Consequently, the height of the cab must be factored into the seat’s design to properly accommodate the stroking mechanism. Too short of a cab leaves little room for the seat to stroke, reset and absorb energy, potentially leading to harsher slam down events.
During emergency situations, ingress and egress are also accounted for as occupants need to evacuate the vehicle as quickly as possible. Often times, ingress is more cumbersome than egress as there isn’t one simple button to push as one has with restraints upon egress.
Comfort is equally important given that occupants can spend up to 12 to 14 hours per day in their vehicle. For this reason, ergonomics and other human factors are included in the design.
“We recognize the value of comfort to the occupant. However, as a seat manufacturer, we have to find the right balance between survivability and comfort as it is sometimes viewed as a trade-off,” added Parsons. “We often take our seats to user communities to help us improve cushions, lumbar support and bolstering, for example.”
Just as with ground vehicles themselves, survivability seats must go through stringent government testing prior to being used in any type of vehicle platform. Federal motor and vehicle safety standards static and dynamic tests, vertical impact tests and live fire blast tests are among some of the tests administered.
“BAE Systems has … an in-house test lab to assist us in building better equipment,” said Parsons.
Drop towers and sled tests help ensure the company is prepared to meet the harshest challenges occupants are encountering in theater. Additionally, high-speed video cameras provide opportunities to assess and simulate dimensions, weight proportions and articulation of movement of crash test dummies, which is extremely useful in designing better equipment, he added.
Moving forward, drivers and passengers can expect to see more seat survivability upgrades in future ground combat vehicles. While a number of ground vehicles are still used today without advanced survivability seats, newer vehicle platforms across a number of service branches are incorporating seat upgrades into their proposal requests.
Mike McDermott is program director at BAE Systems Protection Systems.