A18.104.22.168. Landing Direction Indicator (Landing "T" or Tetrahedron) (Non-Frangible). A
landing "T" or tetrahedron must be located at least 83.82 meters [275 feet] from the edge of a
runway to the centerline of the equipment.
A14.2.20. General Information for Operational and Maintenance Support Facilities. Detailed siting
information is furnished in this section, where appropriate. The list of facilities is divided into two
categories: one related to aircraft operations; and one related to aircraft and facility maintenance.
When the facility has dual use, it is grouped in the category of its predominant function.
A22.214.171.124. Operational Facilities:
A126.96.36.199.1. Aircraft Arresting Systems and Barriers (net engaging systems) (Non-
Frangible). A series of components used to engage an aircraft and absorb the forward
momentum of a routine or emergency landing (or aborted take-off). See AFI 32-1043 for
detailed siting criteria and other information and requirements.
A188.8.131.52.1.1. Current in use aircraft arresting systems installed under previous criteria
and standards may continue in service without waiver if they do not impair operational
safety. The Base Civil Engineer's representative should identify such systems to Flight
Safety and Operations through the Airfield Manager for a determination of whether these
systems may continue in service, or should be programmed for replacement. This should
be done annually in conjunction with the annual waiver review. Such systems are; BAK-12
with Deck Sheave-type runway edge sheaves; BAK-12 systems with two-roller fairlead
beam runway edge sheaves, BAK-9 systems with Deck-Sheave runway edge sheaves; and
A184.108.40.206.1.2. BAK-12 energy absorbers may not be sited less than 83.82 meters (275
feet) from runway centerline. Slopes over tape tubes must comply with criteria for shoulder
grading provided in Chapter 3. Fairlead foundations must be constructed in accordance
with USAF Typical Installation Drawing 67F2011, sheets six and seven, applicable to
three-roller fairlead beams. Protective shelters constructed for on-grade installations must
be constructed from lightweight framing materials and sheathing using connections that
will allow the structure to break away and collapse if struck by an aircraft wing.
A220.127.116.11.1.3. BAK-15 barrier masts and hydraulic system components may be sited
within 10 feet of the overrun edge. This is necessary to minimize the mast height needed to
maintain the centerline height of the net. Foundations must be constructed flush with grade
or grading surrounding the foundations shall be shaped to comply with the grading
allowances provided for shoulders in Chapter 3, Table 3.4.
A18.104.22.168.1.4. Textile Brake aircraft arresting systems may be sited on the runway or
overrun shoulders. Cable pretensioning devices should be sited as far from the overrun or
runway edge as possible. All foundations shall be flush with grade except the leading edge
of the module foundations which have a 76.2 mm (3-inch) or less vertical drop to provide
jet blast protection for the modules. Unidirectional models of this system, such as the MB
60.9.9 are not sited between the thresholds.
A22.214.171.124.1.5. When aircraft arresting systems are decommissioned and removed from
the airfield environment with no intent of replacement in the existing location, all related
structures and foundations must be demolished and removed from the airfield. Grades in
the area must be restored to comply with criteria provided in this manual, as appropriate.