The UKIRT Board has set the following constraints on WFCAM scheduling.

Overall

WFCAM will be installed on the telescope for 75% of the year on average (the WFCAM year is therefore about 274 nights in length). Approximately 10 nights within this will be topsliced for engineering, leaving the WFCAM year at approximately 264 nights in length.

University of Hawaii

15% of UKIRT time goes to University of Hawaii observing programmes; UH WFCAM time is nominally pro-rated according to the WFCAM fraction (75% as above). Therefore the UH WFCAM allocation in a given year will not exceed approximately 40 nights. To ensure PATT access and the uniform completion of UKIDSS survey fields, this time will be approximately balanced within each WFCAM block rather than over a complete year.  A recent renegotiation of UH the UH mode pro-rating means that UH may now typically exchange up to a week of their Cassegrain mode time for WFCAM time (done by monir adjustment of the imstrument mode block lengths).

Japanese time

The Japanese community have access to UKIRT time at the level of up to ten nights per 6-month semester; we assume an average allocation of 12 WFCAM nights per year. Note that this agreement is still the subject of negotiation for Semester 05B onward.

PATT TAG time

Of the remaining 212 nights, 15% or 32 nights will be devoted to PATT observing.

UKIDSS Sky Survey & other Campaign Programmes

The remaining WFCAM time (approximately 180 nights) will be devoted to UKIRT Deep Infrared Sky Survey (UKIDSS) operations. 

The initial two-year plan for UKIDSS Observations originally required a minimum of 290 nights to be put into UKIDSS survey observing over the two-year period.