This data record is used when a stability report is requested from an Aqwa-Librium analysis. The report, written in AB*.LIS file, gives a list of positions of the structure and the corresponding forces at each position. The positions of the structure are calculated by the program at a number of rotations about one or more hinges defined by the user.

Stability reports are only available for Structure 1 and for hydrostatic forces only. The program will produce errors if any other forces are present. The LSTF option is not compatible with this facility.

      2   5  7   11    16    21        31        41        51        61        71
    - --- -- ---- ----- ----- --------- --------- --------- --------- --------- ---------
   |X|   |  |STRP|     |     |         |         |         |         |         |         |
    - --- -- ---- ----- ----- --------- --------- --------- --------- --------- ---------
       |  |   |     |     |       |                             |         |
       |  |   |     |     |       |                             |         |_(5) The Angular Increment
       |  |   |     |     |       |                             |               of the Hinge about
       |  |   |     |     |       |                             |               Global Z (default=1 deg)
       |  |   |     |     |       |                             |
       |  |   |     |     |       |                             |_(4)The Angular Increment about
       |  |   |     |     |       |                                  the Hinge (default=1 deg)
       |  |   |     |     |       |
       |  |   |     |     |       |_(3) The Definition of Hinge Axis Vector (3F10.0)
       |  |   |     |     |
       |  |   |     |     |_(2) Number of Rotations of the Hinge (default=1) (I5)
       |  |   |     |
       |  |   |     |_(1)Number of Rotations about the Hinge (default=30) (I5)
       |  |   |
       |  |   |_Compulsory Data Record Keyword (A4)
       |  |
       |  |_Optional User Identifier (A2)
       |
       |_Compulsory END on last data record in Data Category (A3)

(1) This is the number of angular positions (typically roll angles) for which the forces are calculated.

(2) It is possible to calculate stability about a number of axes. Typically rotation about the X-axis will give roll stability. The stability axis (the hinge) can itself be rotated about the global Z axis, so that pitch stability, or stability for any intermediate position, can be obtained. This parameter is the number of positions of the hinge. If only 1 hinge vector is required, the number of rotations of the hinge and angular increment of the hinge can be omitted.

(3) This is the initial direction of the hinge axis defined as a vector in the FRA. For example, for typical roll stability this would be (1, 0, 0).

(4) This is the increment between the angular positions defined in (1).

(5) This is the increment between the hinge positions defined in (2).