Section 4. IR Route Definition

  1. ROUTE WIDTH

Widths of route segments are determined by the military. The route width will be sufficient to contain all planned activities.

  1. ROUTE ALIGNMENT

Route alignment criteria must be as follows:

  1. All IRs to be flown at or below 1,500 feet AGL should be designed to permit aircraft flying the route to avoid charted, uncontrolled airports by 3 NM or 1,500 feet. Where it is impractical to comply with this criteria, procedures must be established by the scheduling/originating activity to minimize conflict with airport traffic; i.e., identify volume and type traffic, highlight need for increased vigilance commensurate with situation, maintain liaison with airport owner/operator, include appropriate cautionary note in route description: “Avoid flight within 1,500 feet or 3 NM of airport when practicable,” etc.
  2. Subsequent charting of airports within 3 NM of an MTR may require route realignment to conform to the criteria established in subparagraph a.
  3. Routes should be aligned to avoid Class B, C, and D airspace.
  4. During development of routes, consideration should be given to potential conflict with published and unpublished instrument procedures/routes.
  5. Routes should be aligned so that disturbance to persons or property on the ground is minimized.
  1. ALTITUDES
  1. Altitudes must be established for each route segment. Routes must contain the minimum number of altitudes commensurate with mission requirements and may be specified singly, in blocks, or a range from which ATC assignment may be made. Minimum altitudes for each route segment must be established by the military. Altitude information must be reflected on FAA Form 7110-4 as follows:
  1. IRs should depict the highest altitude in MSL terms. The lowest altitude may be depicted in either MSL or AGL terms.
  2. An altitude block must be depicted as the lowest altitude followed by a “B” followed by the highest altitude.

EXAMPLE-

5 AGL B 20 MSL
40 MSL B 60 MSL
SFC B 50 MSL

  1. A range of altitudes from which ATC may assign a single altitude must be depicted as the lowest altitude, in MSL terms, followed by a “-” followed by the highest altitude in MSL terms (when acceptable to the mission).

EXAMPLE-

20 MSL-50 MSL

  1. Unless the route segment is clearly annotated, “for use in VMC conditions only,” each route segment must contain an altitude that is suitable for flight in IMC and can be used in the event of an aircraft systems failure. This altitude must be referred to as the IFR altitude and may be contrary to 14 CFR section 91.177 (Minimum Altitude for IFR Operations) when specifically authorized by appropriate military authority. The IFR altitude must always be depicted in MSL terms. In no case will flight operations be conducted at altitudes less than those specified in 14 CFR section 91.119 (Minimum Safe Altitude, General). In the absence of an established IFR altitude, the IFR altitude is the highest altitude designated for the route segment as depicted in the route description.
  2. All altitudes must be established by the military. The military may use other than FAA standards for establishing IFR altitudes for route segments.
  3. When practical, the designated exit fix altitude must be within an area of ATC radio coverage. When it is determined that ATC impact or other constraints preclude the exit fix altitude from being established within radio coverage, an altitude below radio coverage may be utilized provided procedures for routinely exiting the route (i.e., pre-coordinated clearances, stereo routes, and actions to be taken by the pilot in the event twoway communications are lost) are covered in a letter of agreement.
  1. RE-ENTRY SEGMENTS

Consistent with ATC capabilities, routes may have re-entry segments. To the extent practicable, re-entry segments should avoid ARTCC/CERAP/HCF boundaries.

  1. ALTERNATE ENTRY, EXIT, AND END POINTS
  1. Any point on the route may be identified as an alternate entry/exit/end point. Entry points must precede exit points on the routes/alternate routes with which they are associated.
  2. Whenever a route is modified by designating alternate entry/exit/end points, the route segments associated with the alternate points must be considered modifications to the basic/principal route and may be described and designated as alternate routes.
  3. Any alternate route segments must meet all of the requirements pertinent to the establishment of new routes.
  1. ROUTE REPORTING POINTS
  1. Unless otherwise specified in the letter of agreement, the National Flight Data Digest (NFDD), and the DoD FLIP AP/1B route description, exit points must be mandatory reporting points.
  2. Other mandatory reporting points may be established for ATC purposes. These must be kept to those absolutely essential in providing approved separation between the route user and other IFR traffic. These points must be specified in the letter of agreement, as appropriate, and the route description.
  1. SPECIAL OPERATING PROCEDURES

Special operating procedures may be imposed, but must be held to the minimum required. These procedures may be applied on a route segment basis and need not apply to the entire route. Such restrictions must be a part of the narrative route description as published in the NFDD and DoD FLIP AP/1B (or AP/3). If ATC procedures are involved, they must be included in the letter of agreement governing the use of the route.

  1. LOW ALTITUDE AIR-TO-AIR TRAINING (LOWAT)
  1. LOWAT must be accomplished only on IRs specifically designated for this purpose.
  2. The provisions for an equivalent level of safety for LOWAT training must be contained in a letter of agreement between the ARTCC/CERAP/HCF and the military unit.
  3. LOWAT maneuvers are not “classical intercepts,” but allow for observation and analysis of an aerial attack, initiation of the appropriate defensive response, and continuation of the primary mission with minimal interruption. LOWAT training maneuvers conducted on IRs must be limited to:
  1. No more than a 90-degree turn will be performed on the IR.
  2. LOWAT maneuvers will be terminated as soon as visual and/or radio contact is made by the defending aircraft.
  3. Weather minimums on IRs at maneuvering altitudes must be 1,500 feet from clouds and 3 miles flight visibility.
  1. LOWAT training must be limited to those aircraft with sophisticated operating airborne radar systems.
  2. IRs designated for LOWAT will be coordinated on an individual basis, approved at FAA Washington Headquarters, published in DoD FLIP, and clearly identified as a designated LOWAT route.