Down Time

The down time statistics are based on individual fault reports. In Table 1 I give the general down time statistics for period 49.

A total of 68 fault reports were submitted, with an average time lost of 4 min per fault, for a total down time of 0.3% (0.2% on scheduled observing nights). Of these, 49 reported no time lost, 19 reported $<$ 2 hrs lost, and none reported 2 or more hrs lost.

This compares to a down time of 0.4% over all nights (0.4% on scheduled observing nights) in period 48, and 1.0% over all nights (1.0% on scheduled observing nights) in period 47. Of the 65 fault report in period 48, 40 reported no time lost, 25 reported $<$ 2 hrs lost, and none reported 2 or more hrs lost. Of the 69 fault report in period 47, 48 reported no time lost, 22 reported $<$ 2 hrs lost, and one reported 2 or more hrs lost.

Table 1: Technical down time statistic period 49: 2014-04-01 to 2014-10-01

Night included	Time lost	Nights	Percentage$^a$	Last semester	Last Summer
All nights	265 min	183	0.3%	0.4%	1.0%
Scheduled observing nights$^b$	165 min	160	0.2%	0.4%	1.0%
Technical nights	5 min	23	0.0%	0.3%	0.4%
Service nights	95 min	34.5	0.5%	0.4%	3.2%
Visitor instruments	0 min	0	0.0%	0.0%	0.5%
$^a$ Taking the average length of time within nautical twilight. Exact numbers for each night
are used when looking at ``All nights''
$^b$ Excluding technical nights and visitor instruments

Both the downtime and the number of fault reports were very low this semester again, the former being at an all time low. The last 12 months had also the lowest downtime (0.3%) ever recorded over a full year.