Down Time

The down time statistics are based on individual fault reports. In Table 1 I give the general down time statistics for period 47.

A total of 69 fault reports were submitted, with an average time lost of 14 min per fault, for a total down time of 1.0% (1.0% on scheduled observing nights). Of these, 46 reported no time lost, 22 reported $<$ 2 hrs lost, and one 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 46, and 0.3% over all nights (0.3% on scheduled observing nights) in period 45. Of the 94 fault report in period 45, 68 reported no time lost, 26 reported $<$ 2 hrs lost, and none reported 2 or more hrs lost. Of the 86 fault reports reported in period 45, 69 reported no time lost, 17 reported $<$ 2 hrs lost, and none reported 2 or more hrs lost.

Table 1: Technical down time statistic period 47: 2013-04-01 to 2013-10-01

Night included	Time lost	Nights	Percentage$^a$	Last semester	Last Summer
All nights	947 min	183	1.0%	0.4%	0.3%
Scheduled observing nights$^b$	877 min	163.5	1.0%	0.4%	0.3%
Technical nights	40 min	19.5	0.4%	0.5%	0.4%
Service nights$^c$	652 min	38.5	3.2%	0.7%	0.7%
Visitor instruments	30 min	12	0.5%	0.0%	0.0%
$^a$ 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
$^c$ Excluding service nights with SOFIN

The downtime was relative high, but it was mostly caused by a single failure (see below) and is also not extremely high. When taken the total downtime of the last 2 semesters, the total is actually below the longer term yearly average. The total number of fault reports were at an all time low.