RHS Barrier Theory

[el cid again]

WITP barriers were invented (as far as I know) by Andrew Brown. When he introduced Andrew Brown's Extended Map system, he introduced mini-maps for Aden and Panama - shipping tracks to reach them - and barriers to isolate them from the main map area. It appears the barriers were set wide enough that most tactical aircraft would not cross them to operate in the wrong map area.

RHS Level 5 is identical to Andrew Brown's Extended Map System - is compatable with it - and players may elect to use RHS map art and/or pwhex files for Level 5 in CHS - or vice versa Andrew's map or pwhex file may be used with any RHS Level 5 scenario. This means that things like interior river systems, ferry systems, exterior river systems, a functional Panama Canal (etc) - the differences between CHS and RHS - are available to players of either system according to their preference. This is not an accident - but deliberate and coordinated. RHS was and remains a daughter of CHS, and Andrew and I always believed in offering players alternative options. In RHS Level 5 the concepts of barriers and mini-maps is unaltered from CHS - except that Cobra and I always believed that it was "fair" for the Axis to attack Aden - and originally I believed Andrew gave it victory points for that reason. Turns out in CHS you are not supposed to attack Aden.
On the other side of the map, both CHS and RHS always said attacks on Panama were fair - and the reason not to denude the place of defensive units.

RHS Level 6 introduces map edge movement tracks so ships can move "around the backside of the world" and go from the East Map edge to the West Map edge as they choose. It was a vehicle to proove the concept - which Andrew confirmed would work before the fact in theory. It did not change either mini-map or the approaches to them - nor the theory of how they should be used. But it DID introduce the idea that the map edge movement track was "off the map" - literally on the other side of the world - and that planes should not operate IN that track nor should planes on the main map be set to enter that track. [An air group can be range limited and should never be set to operate at a distance permitting it to enter the bottom edge ship track]

RHS Level 7 significantly alters much of this. It is new and just now entering the end of development. How it might work has not been entirely clear. But salient differences include:

The Aden Mini Map is gone - and Aden itself is split into two locations - Muscat on the map edge (a fully functional base able to be attacked as such) and off map Aden - approachable only by special shipping tracks. Aden is denuded of defenses (except to the extent they are needed to support ships and aircraft) - and it is NOT like RHS Levels 5 and 6 insofar as it is "off limits" to Axis attack (similar to CHS). It is a "meta-base" - as are all the bases on the southern map tracks (which now are multiplied to three). To reflect this there are NO victory points associated with Aden - or the other meta bases.

A new Panama Mini Map is introduced - at the same distances Andrew used - with Panama oriented more correctly -
but with part of the Caribbean Sea added to the mini map area. As in all forms of CHS and RHS Panama may be attacked - but the Axis may not enter the Caribbean Sea - which has many bases not represented in the game. Because operations against Panama require entering the ship tracks - the Axis are permitted to do so from the North or West - any ship track North of the Central Pacific Entry point is fair game - and any size naval unit may enter it.

A new Madagascar Mini Map is introduced. It is similar to the Panama mini map but has a more elaborate approach network. The Axis may approach it from the North or East - but not by the Southern Map Edge movement track.
The two Westernmost bases on that track - Durban and Capetown - are now real bases - and MAY be attacked by air strikes - but are off limits to Axis land and ground units. Similarly, Durban and Capetown may be used as air bases to attack targets on the Madagascar Mini Map or associated barriers.

The basic Level 7 rule re barriers is that aircraft based on land OUTSIDE the barriers may be range set to permit operations in the same map the base is in PLUS the width of the barrier - but not the map on the other side of the barrier (whatever that means - count the hexes to the other side of the barrier - and that is the limit).

This now is modified for shipborne aircraft, which divide into categories.

1) Shipborne seaplanes NOT associated with fast carrier groups should be range limited to one hex. All barriers are now set to one hex wide between tracks - so that means you only search and attack in the hex you are in - OR in the adjacent hex in the same track - but not distant hexes in other tracks/parts of the same track.

2) Shipborne aircraft (including seaplanes) PART OF a fast carrier group INSIDE A BARRIER (that is, on a CV or CVL, or CVS) should be range set so that the aircraft do not operate OUTSIDE the barrier. This is typically a setting of around 3 hexes. This represents the unpredictability and flexability of fast carrier groups to change locations rapidly but does not permit a carrier group far from the main map or mini-map to strike into it.

3) Shipborne aircraft (including seaplanes) PART OF a fast carrier group (that is, on a CV, CVL or CVS) NOT INSIDE A BARRIER should be range limited in a way similar to case (1) above - so they cannot enter a different map - but they MAY enter the barrier. Care must be taken to insure unexpected reaction does not cause this rule to be limited.

4) The new cases of Amsterdam Island (and St Paul island if you have a submarine or seaplane tender able to stop there) are unique. These may be range set to 3 hexes (that is, inside the barrier). This represents the great operational significance of these islands for patrol operations in the area - but does not permit them to influence things on either the main map or the mini map - which is appropriate. [From the next release Amsterdam is a wholly undeveloped base - 0 - 0 - which nevertheless generates supplies (food) - and which can be developed into a base at great cost. In addition to use as a base, submarines with aircraft, and AV, may operate from any coastal hex, as an RHS convention, provided they are not moving.]

NOTE: Axis CV and CVL (and BB and BC) are NOT permitted on the Madagascar Mini Map nor appraoaches to it. But ALLIED ships suffer from no such restrictions. Axis CVS are an undefined case - left to player discretion - and an Allied CVS begins at Durban.

NOTE: Remember the RHS Prime Directive: If you don't think real world commanders would/could do it - don't do it yourself. Thus, Madagascar should not be evacuated of its units before an Allied invasion occurs - because the Vichy government would not do that. RHS does not attempt to list all such restrictions - trusting players to have enough wisdom to grasp the concept. However, if you don't explicitly address every case in house rules, don't be too upset if a different person differs from you on this or that minor case. RHS also promotes uncertainty as a factor in strategic and operational thinking.