The “landing strip” for a thrown jack

See other posts about boundaries and boundary lines.

Article 7 specifies a number of distance-related constraints on a thrown jack. One of them is that “the [thrown] jack must be a minimum of 1 meter from … the nearest boundary of an out-of-bounds area.”   This requirement (unless it is modified, see below) can be a problem on narrow lanes.

We are playing on a marked terrain that is 3 meters wide. Does the one-meter rule in Article 7 mean that the area where we can legally throw the jack— the “landing strip” as it were— is only one meter wide running down the middle of the terrain?

The answer to the question is “It depends…”

The landing strip

Suppose that we have a playing area that contains only one marked terrain (one lane, piste, cadre), so that the boundary lines of all four sides are dead-ball lines. The lane is 4m wide and 15m long. If we measure one meter in from each of the four boundaries, then we have a landing strip in the middle of the lane that is 2m wide and 13m long.

Things get more interesting when we create multiple lanes by dividing a large playing area into a grid of lanes. In this kind of arrangement, the boundary strings that consititute the exterior boundary of the grid, and also the strings across the short ends of the lanes, are dead-ball lines. The other strings, the strings that divide the playing area up into separate lanes, are “guide lines”— that is, they indicate the boundaries of the lanes, but they aren’t out-of-bounds lines (“dead-ball lines”). If we diagram the landing strip for such a grid of lanes, the result looks like this.

Look at lane A. On one side it has an exterior dead-ball line; on the other side is a neighboring lane (B). So the landing strip for lane A (as also lanes D, E, and H) is lop-sided. On one side, the landing strip stays one meter from the exterior dead-ball line around the playing area. On the other side is a neighboring lane— on that side the landing strip can go right up to the guide line. So if the lanes are 4m wide, then the landing strip for lane A is 3m wide, but the landing strip for lane B extends the full width of the lane and is 4m wide.

When the landing strip is too narrow

There are situations where circumstances can combine to make the landing strip too narrow— only one meter wide.

Under FIPJP rules, games below the national level may be played on a lane that is only 3m wide. And in time-limited games, all four boundaries of a lane are considered to be dead-ball lines. This means that in one common situation— during a round of time-limited games played on a grid of 3m-wide lanes— the landing strip for each lane would look like our first diagram (lane L) and be only one meter wide.

The same problem can occur even in non-time-limited games when the lanes are arranged in a long strip, as in the diagram at the right. This kind of arrangement is quite common for competitions that are played on long, narrow areas like the paths in a public park or along a waterfront.

In order to deal with the problems of a too-narrow landing strip, many national federations, clubs, and competitions change the one-meter rule for competitions played on lanes that are only 3m wide. They change the minimum distance from a dead-ball line from a whole meter to a half-meter— a thrown jack must be a minimum of half a meter from the nearest dead-ball line. So even on a lane that is only 3m wide, the landing strip will still be at least 2m wide.