The second week of HBA installation got off to a reasonable start. We managed to get one tile out first thing this morning, but then a thunderstorm rolled through and sent everyone scurrying for cover. But the storm did not last long and we were back out again in no time. From then on, we made solid progress.
This was partly due to the fact we had some additional staff on the site (2 extra compared to last week) and also as the entire team are now well versed with what needs doing. Also, some of the drilling work is now reaching an end (or is waiting on parts from the Netherlands), which has freed up some staff of concentrate on frameset and tile installation.
We discovered a problem with the centre block of tiles and so spent some time in the afternoon, double checking measurements and shifting some framesets and tiles by a couple of centimetres tangentially. The error was due to a chance misalignment of the end two pegs, which meant that the lead frame (H80) had a small rotational error. This became apparent as the frameset for H59 was installed, as over the larger baseline, the discrepancy becomes apparent. In any case, we have fixed the problem and work can proceed in that block.
We've also continued planning work for how to get the array level to extreme accuracy. A system of jacks and stays will be used to bring each tile up to a datum, at which point a series of holding posts will be affixed. This should allow not only for good accuracy now, but also the chance to realign the array level in years to come when the ground is affected by permafrost and surface thawing.
The next tile delivery is expected on Wednesday, with three lorries due to arrive. We should easily have cleared out the last couple of tiles in storage ready to accept the new kit. We also hope that some parts will be included so that we continue with some of the ancillary work.
So, we expect a day of getting organised on Tuesday, in order to deal with what will presumably be a very busy day on Wednesday.