1 - WHT OPERATIONS DURING 2014B ------------------------------- 1.1% of the observing time was lost to technical problems. This is well below the target level of 5%. The numbers of nights allocated to each common-user instrument in 2014B were approximately: ISIS 48.5; LIRIS 21.5; ACAM 28.5; AF2 25; prime-focus imaging 0; OASIS 6; INGRID 0. (Where an observer requested two instruments, e.g. LIRIS + ACAM, the credit has been split between the two.) ISIS remains our most-popular common-user instrument, and ISIS+LIRIS have a 44% share of all nights, and 54% of nights allocated to common-user instruments. These fractions are similar to the average during the last 3 years. The WHT hosted 4 visiting instruments this semester: EXPO, GHAFAS, PNS, and ULTRACAM, in addition to the CANARY experiment in GHRIL. 39 user feedbacks were received for runs during 2014B. All rated the run 'good' or 'excellent'. 2 - TIME-LOSS STATISTICS FOR 2014B ---------------------------------- 36 technical faults, 29 hours lost, mean 0.8 hours per fault. The faults arise in a broad range of sub-systems. Two faults caused more than 3 hours to be lost: 8 hours were lost in August 2014 after a trip of the main-drive encoder breaker prevented movement of the telescope. This trip had gone unnoticed, hence was not addressed during the night. ING is adding an alarm to warn the telescope operator when such a trip occurs. 6 hours were lost in September 2014 due to failure to zeroset the encoder of the prime-focus rotator during an AF2 run (human error). NB these statistics (as in previous reports) refer to *all* nights, including S/D/commissioning, and nights when visitor instruments were used. 3 - ACTUAL USE OF S/D/STANDDOWN IN 2014B ---------------------------------------- Service Observed 11.2 Bad weather 4.0 Technical problems 0.6 D/comm Tel. quality control 0.7 Instr. quality control 3.5 Commissioning 4.5 (CANARY) Aluminising 0.0 Bad weather 3.1 Technical problems 0.4 ---- 28.0 Total S = 15.8 = 11.2 + 4.6 associated bad weather + technical problems. Total D = 12.2 = 8.7 + 3.5 associated bad weather + technical problems. 4 - WEATHER AND TECHNICAL DOWNTIME IN 2014B ------------------------------------------- The last three columns below give for each month the numbers of observing hours lost to bad weather and to technical problems, and the number of nights considered when compiling these statisics (= all those which were not S/D/commissioning or own-instrument). Mon Yr weath tech nights hrs hrs 8 14 12 3 21 9 14 20 2 20 10 14 64 2 23 11 14 129 0 16 12 14 45 4 25 1 15 26 2 18 Chris Benn 14 May 2015