12 August 2002
2-3.2.2 A standard FFM weighs about 1360 kilograms (3,000 pounds) and consists of
nine fiberglass panels, each 1.83 meters wide by 9.14 meters long by 12.7 millimeters
thick (6 feet wide by 30 feet long by 0.5 inch thick). Elastomer hinges 76.2 millimeters
(3 inches) wide connect the panels. When folded, these mats are 1.83 meters wide by
9.14 meters long and 203 to 254 millimeters thick (6 feet wide by 30 feet long and 8 to
10 inches thick).
2-3.2.3 This repair system also includes joining panels and two support mat kits. The
joining panels come in 7.32-meter and 9.14-meter (24-foot and 30-foot) lengths. One of
each size is needed to connect two 9.14-meter by 16.46-meter (30-foot by 54-foot)
mats. The resulting 16.46-meter by 18.29-meter (54-foot by 60-foot) mat is the normal
size suitable for most crater repairs. If larger FOD covers are required, additional mats
may be spliced together.
2-3.2.4 There are two types of support mat kits for the FFM. Mat Kit A contains all
the necessary tools and hardware required to assemble, install, and maintain the
system. Mat Kit B contains the anchor bolts required to attach the mat to the pavement
2-3.2.5 The mat assembly area can be any area near the crater repair. This area
must be cleared of all debris and swept. It must be large enough to accommodate the
unfolding of both mats, allow equipment operations around the mat, and not interfere
with crater preparations. This area should be approximately 30.4 meters by 30.4
meters (100 feet by 100 feet) square, and located a minimum of 30.4 meters (100 feet)
from the crater and off the MAOS.
2-3.2.6 Mats are placed end-to-end about 1.2 meters (4 feet) apart, with the first
panel up and positioned such that both mats unfold in the same direction.
2-3.2.7 Unfold the mats in preparation for being joined together. The top panel of the
mat is attached to a tow vehicle with a nylon strap. A crew of four people, or a forklift
positioned on the opposite side of the mat, lifting each successive panel as the mat is
being pulled open, speeds the unfolding process.
2-3.2.8 Resin flaking at the mat hinge can occur and create a FOD problem with mats
that were procured from the initial manufacturing programs. To eliminate this problem,
make one pass with a vibratory roller down each hinge, followed with a sweeper. This
operation normally loosens and removes the flaking material from the hinges.
2-3.2.9 Join the mats together so they are aligned, the 9.14-meter (30-foot) edges are
even, and the 16.46-meter (54-foot) edges are roughly parallel with each other.
2-3.2.10 Lift one end of the 16.46-meter (54-foot) edge and slip either the 7.32-meter
(24-foot) or the 9.14-meter (30-foot) section of joining panel underneath the raised
edge. Align the holes in the mat with the joining panel bushing holes and lower the mat.
2-3.2.11 Install the top joining bushings and tighten by hand. This process is repeated