Attachment 2 - Encl 1 to PWS-Mission Profile Terrain Description.pdf

M67854-26-I-0202 Attachment 2

Marine Corps Mission Profile Terrain Description

Enclosure (1) to Performance Work Statement Page 1 of 3

1.0 Terrain

The Marine Corps mission profile operational terrain is classified into two overall categories: improved surfaces and unimproved surfaces. Improved surfaces are primary and secondary roadways with some type of all-weather surfaces, man-made improvements, and are subject to periodic maintenance. Improved surfaces range from paved, high-speed roads in excellent condition through rutted and potholed gravel roads. Unimproved surfaces are trails and cross-country “natural” surfaces with no manmade improvements, no maintenance, and subject to variances of weather. Unimproved terrains include, but are not limited to, deserts, grasslands, sand, swamps, forests, tropical jungles, mountains, shallow rivers, and saltwater beaches. The Marine Corps Ground Vehicle operational envelope requires the capability for extended, effective operation on all terrain surfaces, but particularly on unimproved surfaces, during all weather conditions both day and night with limited and poor visibility. Table 1, below, provides a numeric value for the roughness associated with the various terrain descriptions which comprise the Marine Corps Operational Mission Profile.

Marine Corps Operational Mission Profile Terrain Values

Terrain Description Average Speed

Wave Number Spectrum

RMS

Roughness

% of Mission Profile

Im pr ov ed

Su rf ac es

Pr im ar y

Su rf ac es

High Quality Paved Road 40 MPH Gxx(n)=1.4 X 10-8(n)-2.5 0.1 3%

Secondary Pavement 40 MPH Gxx(n)=1.9 X 10-7(n)-2.5 0.2 3%

Se co nd ar y Su rf ac es

Rough Pavement Degraded 40 MPH Gxx(n)=8.0 X 10-7(n)-2.5 0.3-0.5 2%

MOUT 25 MPH WNS Does Not Apply N/A 4%

Loose Surface 35 MPH Gxx(n)=3.0 X 10-5(n)-2.0 0.5-0.7 8%

Belgian Block 30 MPH Gxx(n)=4.0 X 10-6(n)-2.4 0.45-0.9 2%

Washboard and Potholes 30 MPH Gxx(n)=4.0 X 10-6(n)-2.4 0.35-1.2 8%

U n-

Im pr ov ed

Su rf ac e Trails 25 MPH Gxx(n)=4.6 X 10-4(n)-1.9 1.0-3.4 30%

Cross-Country 15 MPH Gxx(n)=9.2 X 10-4(n)-2.1 1.5-4.8 40%

Table 1: Terrain Roughness Profiles

Enclosure (1) to Performance Work Statement Page 2 of 3

2.0 Improved Surfaces

2.1 Primary Surfaces

Primary surfaces are high quality paved, and secondary pavement with Root Mean Square (RMS) values varying between 0.1 inches to 0.2 inches. They consist of two or more lanes, all weather, maintained hard surface (paved) roads with good driving visibility designed for heavy, high-density traffic. These roads have lanes with a minimum width of nine feet (2.75 meters), and road crown to 2 degrees.

Secondary pavement can include significantly degraded (potholes, alligator cracking, freeze/thaw breakup) concrete, macadam concrete or asphalt pavements.

Forces in third world countries will find there is no prevalence of paved surfaces and the paved surfaces that exist are of substandard quality. High quality pavements where Marine Corps Ground Vehicles can run safely at speed consisting of 3% of primary roads. Secondary pavement, which is more typical of third world pavements, makes up 3%.

2.2 Secondary Surfaces

Secondary surfaces are primary roads with rough pavement, loose surface, loose surface with washboard and potholes, and Belgian block surfaces with RMS values varying between 0.3 inches to 1.2 inches.

Third world countries will have large networks of neglected secondary pavement and roads using gravel or similar material as wear surfaces. Rough pavement is two lane roads with degraded shoulders, and marginal subgrades which produce long wavelength swells and additional degradation of the surface.

Grades can vary from 0% up through 6%. Generally, washboard occurs in drier operational areas, whereas pothole gravel roads occur in wet operational areas. These roads are one or more lanes, all weather, occasionally maintained with varying surfaces (e.g., large rock, crushed rock, or gravel) intended for medium-weight, low-density traffic. Bridges on secondary or unimproved roads are typically unreliable in terms of their load bearing capacity, meaning that military traffic must reinforce them, cross with caution, or use available alternative crossing methods, such as fording. Grades can vary from 0% up through 15%. Rough degraded pavement accounts for 2% of secondary roads. Loose surface roads account for 8% of the secondary roads. Wash boarded and potholed surfaces makes up 8% due to weather and traffic deteriorating loose surfaces. Belgian Block makes up 2% of secondary roads.

The Military Operations within Urban Terrains (MOUT) combines extensive manmade structures with characteristics of the terrain types described above, but essentially characterized as a mix of improved surfaces and a variety of discrete obstacles. However, as conflicts within built-up areas escalate, collapsed buildings and other damaged structures produce rubble that increases terrain roughness. Sight distance is severely limited and intersections require blind 90 degree turns to narrow streets. Buildings or walls lining streets create channelized pathways which make rubble piles, vehicle carcasses, bomb craters, or defender created obstructions effective barriers requiring a capability to go over rather than around them.

There is limited room for vehicle maneuvering to go around obstacles or avoid kill zones due to narrow streets and alleys. Damaged water systems can flood streets to create wet pavement, weaken pavement substructures, destroy substandard pavement, rut unpaved roads, and produce mud. Relatively good pavement will deteriorate as it is subjected to repeated military combat and tactical wheeled vehicle traffic. The discrete descriptions of the MOUT terrain are detailed in Table 2. MOUT terrain accounts for 4% of the total mission profile.

Enclosure (1) to Performance Work Statement Page 3 of 3

MOUT Terrain Discrete Event Description

Discrete Events Description Average Speed

Street Curbs and Obstacles Drive over 6-inch vertical curb 15 MPH City Debris Climb over 2 feet rubble piles 10 MPH City Obstacles Negotiate randomly spaced fix obstacles 10 MPH Wet Pavement Drive through 1/8-inch water covered surface 30 MPH Torsional Event Drive across 18-inch deep by 24-inch diameter mortar craters

10 MPH

Ditch Slope / Riverbank Maneuver a 40% 8-foot side slopes 5 MPH Climb Multiple Vertical Steps

Climb and decent 20-foot and 6-inch stairs 5 MPH

Table 2: MOUT Discrete Descriptions

3.0 Unimproved Surfaces

3.1 Trails

Trails are one lane, unimproved, seldom maintained loose surface roads intended for low density traffic with RMS values varying between 1.0 inches and 3.4 inches. Typically trails have no defined road width, large obstacles (rubble, boulder, logs, and stumps), cross ditches, washouts, steep slopes, and no bridging/culverts. Naturally occurring grades can vary from 0% up through 40%.

3.2 Cross Country

Cross country is terrain not subject to repeated traffic with RMS values varying between 1.5 inches and

4.8 inches. Cross-country terrain can consist of tank trails with crushed rock or having large, exposed obstacles (rocks, boulders, etc.), but there are no roads, routes, well-worn trails, or man-made improvements. This includes, but is not limited to, flat desert, marshes, vegetated plains, jungle, dense forest, mountains, and urban rubble. Naturally occurring grades can vary from 0% up through 60%.

4.0 Unique Environmental Requirements

The operating environment listed in Table 3 with their corresponding unique terrain conditions provide additional detail the Marine Corps Ground Vehicles will encounter during worldwide combat operations.

Operating Environments MOUT Littoral Landing Cold Climate Mountainous Terrain

Streets Curbs and Obstacles Fording Ice Cross Down Trees City Debris Live Sand Dunes Snow Wash Outs Wet Pavement Sand Wash Cross Ditches Torsional Event Sand Up to 60% Grades Climb Over Defensive Obstacles

Mud Climb Over Rocks Obstacles

Ditch Slope / Crater / Riverbank Rice Paddy Climb Multiple Vertical Steps

Table 3: Environmental / Terrain Breakdown