NATC Test Course Descriptions
The Churchill Course is a local gravel road located on a
lower terrace. It is level to undulating with slopes up to 3 percent. The
surface contains some washboard effect with varying degrees of depth and
spacing. The alignment is mild, containing only a few curves requiring a
decrease in speed to negotiate them safely.
This course is located on bottomland flat and lower terrace terrain with slopes up to
3 percent. The course is a 3 mile gravel and clay road consisting of man-formed
and natural terrain. The surface roughness is moderate, with limited washboard,
potholes, water erosion, and rock outcrop features. Periodically this road is
graded. The course alignment is mild, although it contains several sharp curves.
Perryman I is an old railroad bed located on a level, lower
terrace and bottomland flat. The bed was constructed from in-situ materials
consisting of fine-grained soils with some rock. The course is rough due to old
ruts and potholes. Portions of the course are flooded when required for testing
purposes. The alignment is reasonably straight, but does contain some mild
This course is located in a bottomland flat with slopes up to
about 3 percent. The in-situ material is a mixture of fine and coarse-grained
soils with some gravel. The surface is moderately rough with ruts and potholes
0.5 to 5 inches in depth. The course alignment consists of straight and mild
This course is located on a bottomland flat and a lower,
level terrace. The soil is indigenous and it is made up of fine-grained
material. The surface profile is similar to Perryman IV except that the
amplitude of undulation is less severe.
Perryman IV is located in a bottomland meadow. The course was
constructed of in-situ fine-grained soil materials which simulate marshland.
Random man-made conditions with varying frequency and amplitude magnitudes has
produced an irregular surface. Vehicle break-over angles are critical to
negotiating this course.
This course is located on an upland slope and plateau. It is
hilly with slopes up to 30 percent along the course. The material is natural,
consisting primarily of boulders mixed with gravel, sands and some fine sands.
The surface roughness is moderate to severe. The alignment of the hilly portion
of the course is a combination of switch backs, and on the upland plateau, the
course is moderately to severely undulating.
This course is 1,970 feet in length. The course was built
based on DFMV measured profiles of the Aberdeen Test Center Belgian Block
course. It is made up of naturally undulating terrain covered with basaltic
rock. Additional “Belgian Block” courses used to simulate the various
cobblestone roads found around the world are also available. The concrete block
course provides a random combination of pitch and roll, as well as high
frequency, low amplitude vibration. The course is exactly one-half the length of
the standard APG Belgian Block course. The course provides high energy inputs to
wheeled vehicles and is utilized in certification to MIL-STD-810.
This course is formed by a mixture of clay and cementable
materials. The course is 411 feet long (one-half the length of the APG 2"
washboard course) with an amplitude of 2 inches and a 2 foot peak-to-peak
spacing. The course form is sinusoidal and is utilized to evaluate wheeled
vehicle suspensions. This course is certified to the requirements of
The radial washboard course is 243 feet long and is formed
from clay and cementable materials in a packed clay base. This course is
sinusoidal with a varying amplitude from 2 inches to 4 inches and a wavelength
of 2 feet to 5 feet. This course is the same length as the APG radial washboard
course and is certified to the requirements of MIL-STD-810.
This course is 798 feet long. It is a continuous sinusoidal
wave form with an amplitude of 6 inches and a wavelength of 6 feet. The course
is constructed of a mixture of clay and cementable materials. The course is
certified to the requirements of MIL-STD-810.
3" Spaced Bump
This course is 764 feet long and is constructed of spaced
timbers set in a concrete base. The timbers are angled and rounded to provide a
3 inch high obstacle. These bumps are irregularly spaced and are angled to the
vehicle path to provide random shocks to the vehicle system. The obstacles are
spaced to allow the vehicle suspension to "settle down" between impacts. This
course is certified to the requirements of MIL-STD-810.
Standard Slag Road
This paved test area is 11.0 miles in length; 4.5 miles of
the course is straight and level. The remainder of the course contains curves
and slight grades. This asphalt road was built for axle loads to 80 tons and
gross vehicle weights to 160 tons. This road is utilized for high speed,
dynamometer, braking, cooling, and handling tests.
Fort Churchill Road - West End
This course is 10.6 miles of graded gravel surface. Fill
material includes both barrow pit and 3/4" minus processed river gravel. The
sub-surface is compacted clay and sand. This area has straight and level
sections for 2 miles with intermittent left and right curves. The road width is
30 to 40 feet.
Hooten Wells Road
This test area is 11.1 miles of maintained sand and gravel
road on a natural base with intermittent curves and straight level sections.
Road width is 25 to 30 feet.
Other Gravel Roads
There are numerous gravel roads in the test area with some
gravel roads more than 50 miles in length. A variety of aggregate overlay and
base are available.
Asphalt/Paved Roads - Public
Within a 60-mile radius are five major federal highways including Interstate 80 as the
primary east-west test route. Linking these major highways are ten connecting
state routes. On these roads, conditions vary from 50-mile straight and level
stretches in the valley floor to curved or straight grades up to 8 percent
traversing the mountain ranges. Low traffic density allows for optimum
Prepared and natural side slopes up to 40 percent are
available on the facility. Base materials include compacted clay/loam and/or
crushed basaltic rock. Prepared slopes include 10, 20, 30, 35 and 40 percent
with lengths up to 500 feet.
Prepared slopes include 5, 10, 20, 30, 35, 40, 50 and 60
percent on sand, sandy/clay/loam or basaltic rock base. Natural grades are
available up to 70 percent. Length of grades vary from 200 to 750 feet. There
are also asphalt slopes and concrete ramps built to support gradability and
parking brake tests.
Simulated Loading Ramp
A 35-foot concrete ramp is available. This ramp has a 30
Bridging and Ditch Profile
Ditches from 3 x 4 feet to 6 x 12 feet are used in tests to
examine mobility characteristics. Ditch areas are simply modified to provide the
necessary basis for evaluation.
A unique area of similar design to the wave course, this
course combines the evaluation of the angle of approach and vehicle flexibility.
Frame twist excursions have been established and utilized in previous durability
Turning Circle Test Area
There are two turning circle measurement areas. One is an
asphalt section of 10,000 square feet. The other is a level, hard-packed clay
area which can accommodate any vehicle size.
Single Event Impact Course
The test course is approximately one mile long and has a
random assortment of naturally occurring chuck holes. Approximately 30 chuck
holes are found in the hard-packed clay/basalt road bed. Although this is a
natural phenomenon, the ground is sufficiently packed so that the chuck holes
have relatively constant depth throughout the test. Average depth is 4 inches
with a slope of 40 to 75 degrees. Additional chuck holes can be dug to meet test
This area not only provides fill material, but is utilized in
tests on all types of loader construction equipment. Three different surfaces
within the pit (sandy/loam/clay, 3/4" to 2" basaltic rock in sandy clay; and 2"
to 3" sharp basaltic rock embedded in sandy clay) provide useful tire durability
Coral Spike Test Area
Approximately 30 square miles of sharp volcanic spikes was
classified by the U.S. Transportation Corps in l960 as the only simulated
Pacific Coral test area in the United States.
Abrasive Mud Traction
This is a test area with controllable moisture content
designed to accommodate any vehicle size. The course length is variable,
depending on requirements. Course material is sandy/clay/loam with a hardpan
clay base. Mud depth and cone index readings are available to suit specific test
This course is similar to the abrasive mud traction area
except for the soil condition. The soil is composed of a fine-grained clay
material with a hardpan base.
Four Mile Flat
This test area consists of 32 square miles of inorganic
fine-grain clay utilized for both traction and "go, no-go" mobility
determinations. Specific test areas, ranging in cone index from 75 down to 5,
This course consists of 100 acres of fresh-water-fed test
areas with elevation changes up to 100 feet. The soil base is sandy/clay/loam.
Downed timber, grasses, standing water, and heavy plant growth are prevalent.
The marsh and swamp mobility evaluation area is located at
the east edge of Lake Lahontan Reservoir. The soil base is clay with a variable
cone index. Vegetation of heavy to tropical density is found on this course.
Certain portions of this test area are accessible to high mobility vehicles
Five primary fording areas have been established in the
Carson River. Although each has a different depth, all have solid packed rock,
gravel and sand bases and can be excavated to provide required depths. A variety
of natural and prepared ingress and egress courses with slopes up to 70 percent
can be found in the fording areas. River bank materials include fine-clay soil,
river rock and sand. Vegetation and natural obstacles are available along the
7.5 miles of deeded river area. Course lengths vary from 100 feet to one mile.
Static Water Fording and Leakage Evaluation
Two primary test areas have been established. The first is the NATC salt
water fording trough, which is 14 foot wide by x 100 foot long, concrete base
trough with 10% ingress and egress slopes. The fording trough can be filled with
various controlled salt solutions to seawater conditions and the height of the
trough is sufficient to allow water depths up to 60 inches.
The second area comprises natural narrow bays at Lahontan Reservoir and
provides shallow and deep water fording. Coarse sand is primarily lake bottom
material. Ingress and egress slopes up to 60 percent are available.
Stone Peck Abrasion
This course provides 3/4 minus gravel typical of American Association of
State Highway and Transportation Officials (AASHTO) low volume road surfaces.
This gravel is selected for its sharp faceted surfaces and is monitored
regularly. The gravel is typically thrown up by the tires and can initiate pits
in the painted surface, producing sites where corrosion can initiate on the
vehicle’s base metal.
This event introduces small particles that can enter various crevices and
exposed components within the test vehicle. These particles trap moisture and
corrosive materials increasing time of wetness underneath the accumulated grit
and keeping contaminants against the surface of the vehicle. Further, the grit
trough produces abrasion to various exposed underbody surfaces and coatings. The
grit trough incorporates clay and sand particles, as well as sodium chloride and
calcium chloride. The base of the grit trough is concrete so that the vehicle
can travel through the trough at various speeds and splash the grit material
onto the underneath and sides of the vehicle. The course is approximately 200
feet in length with sloping entrance and exits on each end. Grit depth is
maintained at 8 inches and 4 inch height alternating bumps are present in the
trough to induce body flexing and twisting in the test vehicle.
Salt Splash Trough
This event is designed to simulate the typical splash and spray which occurs
when vehicles are operated on winter roads that have been salted as part of road
maintenance. The trough consists of a concrete bottom with the ability to adjust
the depth of the salt-water solution. The vehicle speed can be adjusted to
simulate the appropriate spray. This is a low to moderate speed event with the
salt bath having a controlled solution prepared in accordance with customer
specifications and a maintained depth of 8 inches.
Halo Spray Trough
The spray bar and reflect curtains of this event ensure that the sides, roof,
undercarriage and hood of the test vehicle are exposed to rain and spray
conditions typical of operation during storage/transport and
embarkation/disembarkation from military landing craft, as well as
parking/storage near shore areas. The trough consists of a concrete bottom with
the ability to adjust the depth of the salt-water solution. This is a slow speed
event. The controlled solution is prepared in accordance with customer
specifications and the spray bar is height adjustable to account for different
Underwater fording tests can be accomplished in the same
areas as those described above.
Several concrete and asphalt ramp areas are available at
Lahontan Reservoir. These ramps are not necessarily required for vehicle entry
to the lake.
Shallow and Deep Water Swimming Areas
Lahontan Reservoir, which has 155,000 acre-feet and a depth
from as little as 5 feet to more than 50 feet, provides a significant swimming
capability evaluation test area. Both calm and wave (1-2 feet) conditions are
These test areas are on or within a 60-mile radius of the
main NATC facility. In more than 36 years of vehicle operation, NATC has yet to
be unable to meet a client's test area requirements. If an area does not exist
in natural conditions, it can be constructed or simulated.