Chapter 8

Driving with Slat Armor

Most Stryker variants share similar driving characteristics. These common characteristics change significantly when additional equipment and armor packages are added. This chapter deals with the most performance altering piece of equipment that is regularly added to the Stryker vehicle: the slat armor package.

SLAT Armor  

8-1.        The add-on system that will most affect the Stryker's driving characteristics is the slat armor package. As shown is the pictures below (Figures 8-1 and 8-2), slat armor consists of a series of steel cage-like panels that surround the vehicle. Each panel is mounted on the body of the Stryker using steel mounting hardware. This increases the length of the Stryker by 1 1/2 feet and the width by 1 1/2 feet. These panels each have different weights, but the entire slat system adds approximately 4,920 pounds to the weight of the vehicle.

 

Figure 8-1. Slat armor package.

Figure 8-2.  Slat armor package.

8-2.        The combination of weight and increased size of the vehicle, coupled with how the slat armor package is mounted, significantly changes Stryker vehicle driving characteristics. Affected areas include how it reacts to quick maneuvers, its ability to maneuver through confined areas, and rapid stopping ability.  Units should train slat armor driving in confined driving areas with experienced Stryker drivers assisting as a ground guides.

Slat Armor PMCS

 

Front of Vehicle

8-3.        Drivers visually check the vehicle front for damage and loose or missing hardware. They also inspect some mounting bolts for looseness. If bolts are loose, they tighten. Maintenance should tighten the mounting bolts to the proper torque value at the first opportunity.

Left Side of Vehicle

8-4.        Drivers visually check the left side of the vehicle for damage and loose or missing hardware. They also inspect some mounting bolts for looseness. If bolts are loose, they tighten. Maintenance should tighten the mounting bolts to the proper torque value at the first opportunity.

Rear of Vehicle

8-5.        Drivers visually check the rear of the vehicle for damage and loose or missing hardware. They also inspect some mounting bolts for looseness. If bolts are loose, they tighten. Maintenance should tighten the mounting bolts to the proper torque value at the first opportunity.

Right Side of Vehicle

8-6.        Drivers visually check the right side of the vehicle for damage and loose or missing hardware. They also inspect some mounting bolts for looseness. If bolts are loose, they tighten. Maintenance should tighten the mounting bolts to the proper torque value at the first opportunity.

Tire Pressure (psi) with Slat Armor Installed

8-7.        For highway (primary road) operations/marches, the Central Tire Inflation System (CTIS) must be turned "OFF". Tires must be inflated to 95 psi; vehicle speed must not exceed 45mph. This maximum speed is for ideal road conditions (straight sections with no visible obstructions). Drivers must use common sense and reduce speed when road conditions are not ideal. Weather conditions, an increase in traffic, reduced road width, turns/curves, hillcrests, and adverse terrain are all potentially dangerous conditions. For cross-country movement requiring greater traction (soft soil, mud, or snow) and slow speeds, switch the CTIS "ON" at 61 psi and select "HIGHWAY" setting (81psi) as required by METT-T. When the CTIS is "ON" at 81 psi, a dash up to 40 mph for 1-hour duration is acceptable. For terrain ranging from cross-country to secondary roads, the ICV may be driven with the CTIS "ON" at 81 psi. This CTIS setting should also be required by METT-T and the unit commander's judgment. With resumed extended secondary road movement as soon as the tactical situation permits, the CTIS should be switched "OFF" and the tires inflated to 95 psi.

Installation

8-8.        Slat armor is installed as a team effort of the vehicle crew and interim contract logistics support (ICLS).  The weight of slat armor (4,920Lbs) and height of the vehicle places tremendous strain on crews when installing the armor on more than one vehicle. Environment (hot or cold) can also slow down the process and cause injury due to fatigue from around-the-clock assembly. To assist in the safety and assembly of slat armor, include generators for night assembly and air compressors for impact wrenches.

Set up work details

8-9.        Handling and installing slat armor will wear down installers. Installers should therefore be rotated regularly to lesson safety hazards to personnel and equipment. A minimum of three personnel are required for installation due to the weight of panels and plates. Store Stryker components that cannot be reinstalled with slat armor installed.

Install slat armor in stages to save time

8-10.     A simple thumb-nail sketch of armor assembly follows:

    (1)     Prepare the vehicle.

    (2)     Mount plating.

    (3)     Install brackets.

    (4)     Install armor.

    (5)     Replace components that were taken off.

    (6)     Configure load plan.

    (7)     Pick up Soldiers and move out.

Maneuverability

8-11.     When equipped with slat armor, Stryker off-road vehicle operation increases tire/ suspension system wear and fuel usage. The increased vehicle size produced by slat armor also affects Stryker maneuverability when traveling on roadways and crossing bridges. Following are driving instructions for slat-armor equipped Stryker off-road operations:

l        For highway (primary road) operations/marches, the Central Tire Inflation System (CTIS) must be turned "OFF".  Tires must be inflated to 95 psi and vehicle speed must not exceed 45 mph. Maximum speed is for ideal road conditions (straight sections, no visible obstructions).

l        For cross-country movement requiring greater traction (soft soil, mud, or snow) and slow speeds, switch the CTIS "ON" and select "HIGHWAY" setting (81 psi) as required by METT-T factors.  With the CTIS "ON" at 81 psi, a dash up to 40 mph for a 1-hour duration is acceptable.

l        For terrain ranging from cross-country to secondary roads, the ICV may be driven with the CTIS "ON" at 81 psi.  Again, this is directed by METT-T and the unit commander's judgment.  With resumed extended secondary road movement and as soon as the tactical situation permits, the CTIS should be switched "OFF" and the tires inflated to 95 psi.

Off-road operation

8-12.     When moving off-road, slat-armored Stryker weight effects cant. Drivers should move slow over rolling terrain and remain situation-aware of ground to be covered.

l        Reconnoiter through the use of maps and dismounted elements will provide situational understanding on routes to be taken.

l        Avoid road shoulders.

l        Move up or down the forward slope of hills, never along the side of hills.

l        Search out hardpan surfaces.

l        If forced to travel over soft ground, one steady speed should maintained to avoid bogging down. Move slower on rough terrain.

l        Hills and gullies should be avoided to lessen strain on the Stryker power pack and suspension system.

Crossing obstacles

8-13.      Obstacles should be moved around to save the time it would take to prepare obstacles for crossing. Additional weight can force units to travel only hard surface roads to slowdown additional tire wear and strain on the power pack and suspension system.

l        Movement should be slower on rough terrain.

l        Hills and gullies should be avoided to lessen strain on the power pack and suspension system.

l        Set up petroleum, oil, and lubricant (POL) convoys and re-supply points.

Require bridge support

8-14.     Some brides have single lanes. Most have two. Very few have more than two.  In most cases, Strykers with slat armor will be either too heavy or wide to cross.

l        Infantry will have to dismount and provide security to the entrance and exit points of bridges.

l        The vehicle commander may have to walk the vehicle across, especially during hours of limited visibility when driver vision is impaired by slat armor placement.

l        Operational time and distance must be considered when slat armor is installed. Reduction in speed will lesson damage to the suspension system and fuel consumption.

slat armor-equipped stryker Recovery Operations

8-15.     Recovery operations are limited due to close proximity of two Stryker vehicles when slat armor is installed (on the front and rear ramp of towing and towed vehicles). Drivers must be trained on towing procedures to keep from damaging the towing bar, breaking towing pintles, and damaging or dislodging slat armor boxes. Training should include:

l        Turning around.

l        Performance of an 8-point turn-around.

l        Backing up and crossing rolling terrain.

Two-Piece Tow Bar

8-16.     Towing Strykers with slat armor requires the use of the new two-piece tow bar. The standard tow bar issued for normal Stryker use can cause damage due to turning capability and added space when armor is added.

Slat Armor-Equipped Stryker Vehicle Operation

Height management system with slat armor installed

8-17.     To keep wheels from rubbing the hull, drivers must make adjustments to the height management system when moving from hard service roads to off road surfaces.

Operation of hatches and ramp with slat armor installed

8-18.     Hatches should be held when opening and closing to eliminate undue stress on hatch springs, latches, and hinge supports. Care should be taken while opening and closing vehicle hatches when the vehicle is parked on a slope. Gravity and the weight of the hatch can pull personnel out and can crush them against the side of the hull.

Operation of ramp with slat Armor installed

8-19.      When the slat-armor equipped Stryker vehicle ramp is being lowered it should not be exited until completely open. Personnel should also stand away during the lowering process.

DVE operation

8-20.      Finally, drivers and vehicle commanders should be familiar on DVE placement changes when operating the vehicle with or without slat armor.