Gap Filler Detail

1960 – National Archives of Canada

SECRET

APPENDIX "A"

S10-136-80/5 TDO329(ATSC)
7 Dec 60

CONCEPT OF OPERATIONS

8 July 60

The concept of low level operations follows the recent CINC requested change in mission/concept viz "To defend the most vital areas of the US and Canada". There are two such defined areas:- the Northeast and the West Coast.

In analyzing the defense of the Northeast vital area "Island", it becomes apparent that the need to defend against low level attack from the West becomes much more important in the Reduced Air Defense Program. The reduction of defense capability across the central Canada-US border area increases the possibility of mass penetration at high altitude through this thin line (using a radar-busting corridor tactic). Once through this line, the raid could turn East to the vital area and be relatively free from concentrated attack until they come within the range and control capability of the Northeast defenses. Since the raid would not need to drop down to low level until late in their flight, their penetration range will be considerably increased. Moreover, since the raid drops below 2000 feet in the flat plains area, it would not be tracked until reaching 500 feet coverage area.

Accordingly, the extension of the southern and western portion of 500 feet coverage in the Northeast area must be designed to give all the low level weapons sufficient time to react and to intercept prior to bomb release line. In this direction of attack, coverage "forward" of the weapons base is coverage to the West.

In an attack on this vital area from the North, the concept of defense in depth is valid at all levels of attack. Hence, the ability to bring ever-increasing pressure of weapons as the raid penetrates deeper into the area at low level, depends directly on the continuity of low level radar coverage. The problem of timely re-identification at low level makes solid coverage throughout the vital area critically important.

Low level coverage in this vital area must also be related to weapon density and deployment. Fighter interceptors with low level capability will be deployed in strength throughout the area with the provision and the strength of fighters at Canadian bases is not certain. BOMARC B weapons are planned for deployment along the North perimeter and East Coast of this area. The final decision on BOMARC B has not been made; however, fighters with low level capability are assumed to be at Northern US bases whether BOMARC is provided or not, and are assumed to be deployed elsewhere to cover the same area as BOMARC B in the event the missiles are not provided. Accordingly, the same concept of low level operations and the same criteria of low level coverage remains valid whether BOMARC B is provided or not. Additional low level capability is provided by NIKE HERCULES weapons deployed around specific targets throughout this vital area.

In relating low level coverage and weapons, it must be recognized that the coverage and siting of low level radars must be decided now and could be a limiting factor in the next few years (61-65). On the other hand, improvement in low level weapon capability can and must be expected during this time to match the low level threat. Re-siting radars at a later date to match an improved low level weapon capability is a greater problem than the deployment or re-deployment of improved weapons.

In the criteria outlined hereunder, the forward coverage to the North has been reduced from 230 NM to approximately 180 NM in cognizance of the following:-

Reduction in the number of missiles at Northern bases (with only 28 missiles, the last missile intercept is still made well forward of the base).
Overall budget limitations dictate that serious holes would exist in the center and western part of the vital area unless some reduction is made in the extent of the northern coverage.
Coupled with (b), the nature and accessibility of land north of the 180 NM line will make installation and maintenance cost run very high.

In summary, on a cost/effectiveness basis, central and western coverage of this area is more important than additional northern coverage (past 180 NM).

The north limit of coverage is defined along a latitude rather than a scalloped perimeter associate with specific weapon bases, thus maintaining a nearly constant latitude of first intercept.

West Coast Coverage - The concept here is conditioned by the geography of the area. With the major targets on or very near the coast line, a band of land based coverage, contiguous with airborne off-shore coverage will provide for the optimum defense along the most probable attack routes, with the weapons that will be available.

GAP FILLER CRITERIA

Criteria for the Gap Filler Deployment Plan associated with the implementation of "Plan X" are prescribed herein.

The quality of coverage should be the same high quality (FPS-63 type) throughout the areas described herein:-

Priority I - Northeast Area. Coverage down to 500 feet over flyable terrain (2000 feet over mountainous terrain)) within the following area:

49-30N, 95-00W to 49-30N,64-00W to 44-30N, 64-00W down the east coast (and contiguous with ALRI coverage) to 37-00N, 76-00W (Langley) to 39-00N, 90-00W (St Louis) to 46-00N, 97-00W to 49-30N, 95-00W. Gaps in horizontal coverage patterns are permitted provided they do not exceed 25 NM in any dimensions.
Priority II - West Coast Area. Coverage down to 500 feet above flyable terrain (2000 feet over mountainous terrain) for a band 150 NM in depth from coast line radar coverage and extending from Vancouver, BC to the Mexican border. West coast land based radar coverage to be contiguous with AEW coverage.
Priority III - Central Canada-US Border. Coverage down to 500 feet above flyable terrain (2000 feet over mountainous terrain) in a perimeter band 100 NM wide extending from the West Coast coverage to the Northeast area coverage. The band will be located to take maximum advantage of existing radar but will be approximately along the Canada-US border.
Priority IV - Coverage down to 500 feet above flyable terrain (2000 feet above mountainous terrain) in a perimeter band 50 NM wide extending from the Northeast Area coverage, south along the east coast to Patrick, Florida and west across the southern border to join the West Coast coverage. This band will be located to make the maximum use of existing radars.
Coverage down to the 2000 feet is required in the zone bounded by the area of 500 foot coverage and a line running from 31 deg 30 min N 108 deg 00 min W to 37 deg 00 min N 180 deg 00 min W to 37 deg 55 min N 114 deg 00 min W to 45 deg 20 min N 114 deg 00 min W to 45 deg 20 min N 107 deg 45 min W to 43 deg 50 min N 107 deg 45 min W to 43 deg 30 min N 100 deg 30 min W to 43 deg 30 min N, 94 deg 30 min W to 38 deg 30 min N 93 deg 30 min W to 37 deg 40 min N, 89 deg 40 min W to 38 deg 30 min N, 87 deg 30 min W to 37 deg 45 min N to 80 deg 45 min W to 36 deg 00 min N, 82 deg 00 min W to 34 deg 00 min N, 91 deg 20 min W.
Where coverage requirements contained in Priority II, III and IV areas and that area described in (e) above, cannot be fully met through the use of existing and firmly funded radars, the coverage afforded by those radars will be acceptable.

In the event that the coverage requirements for the vital Northeast Area cannot be fully met, the southern and western boundary of this area will be modified to the following:

37-00N, 76-00W (Langley) to 40-40N, 89-30W, (-P-95) to 46-50N, 92-00W (Duluth) to 46-50N, 95-00W to 49-30N 95-00W.

The degree of coverage in the Priority III and IV areas will be that afforded by existing and firmly funded radars.

Mountainous terrain will be that described as mountainous in USAF/USN Radio Facility Charts, except for that portion of indicated mountainous terrain in the Eastern US and Canada north of 40-30N which will be considered as non-mountainous.