131 Bty Reports, Survey Section
September 1968

15. Initially we intended to place FSPB LONGREACH on theatre grid but a control point originally fixed by Topo Svy some 3000 metres from the FSPB could not be located despite considerable assistance from the local villagers. The disappearance of the control points is a common occurrence and we hope to form some system of regular checks on known existing points.

Op Diamantina
16. The FSPB was eventually fixed by a traverse from a map spotted road junction. Heavy rain fell continually and orientation was by theodolite compass. When the weather cleared the following day a simultaneous sun shot from a BP 8000 metres away was carried out and checked the bearing to within 2 mils.
17. In preparation for survey to FSPB DAGGER (YS 437715) 4km due north Nui Dat, we were permitted to do a thorough reconnaissance prior to the move and were able to partially complete the scheme before occupation. The result was that the FSPB was on theatre grid within an hour of the occupation. The method used was a long range traverse from Nui Dat and in addition points were established on the way in case of future use as a base for aerial survey. It should be noted that a recce of the FSPB, especially a thorough recce, is rarely acceptable in this theatre and the scheme was timely as LZ preparations is normally required ASP.
18. FSPB GABO (YS4682) was placed on theatre grid by a long range traverse from a control point located at the Xa Bang ARVN fort. For FSPB LONGREACH on second occupation, our previous BP was still present and this task required minimum assistance.
19. The subsequent move to FSPB COOLAH (YS 397864), WATTLE (YS 3591) and DAMPIER (YS 365864) had minimum survey assistance. COOLAH had previously been fixed whilst WATTLE and DAMPIER were screened with heavy tall growth and no control points were located within surveying distance. The only possible answer would have been aerial survey but to establish suitable bases would have required an operation in itself, hence these bases were map spotted. In all moves each gun battery was accompanied by a survey party to check orientation.
20. Four members of the detachment did Trade Testing during (unreadable) and qualified for their grouping.
21. Some of the Sound Ranging equipment has arrived, but work cannot commence until the final shipment arrives which contains microphones, plotting boards and scale arm.

UNIT WORKS
17.The huts being built for accommodation of the Sound Ranging members giving them ready access to the Sound Ranging CP are near completion and will be occupied when sandbagging is completed.

MANNING
29. This month the Svy Officer was employed full time shift work in the Arty Tac plus detached as a liaison officer to US Base Bearcat for Op WINDSOR.

Capt PM Perrin, OC 131 Div Loc Bty