Eagle (F-15)
Air Traffic Control Developmental
Situational Awareness; Workload
ATC Issue All Types
General None Reported / Taken
Procedure
I was working [two] combined sectors. ZZZ Tower called me and asked if our RADAR was going out. The F-15s' flight plans were non-RADAR routing. I told Tower at the time; no it was not going out; the F-15s could fly the departure procedure. I was then told by the CIC that the RADAR was going out. I had one flight in the air and the second flight was departing. Having the RADAR taken away without notice increased my workload immensely. I had the first flight not in RADAR when my D-side released the F-15 flight; to the same altitude; we were able to stop the second F-15 flight from climbing to the same altitude as the first F-15 flight. I believe my D-side; who is still in training; was confused as to what to do; so he/she just said released. Controllers need more than a 5 minutes notice when taking the RADAR. I believe this incident wouldn't have happened if they gave us more time.  Give controllers more than a 5 minutes noticed when taking a RADAR site.
Enroute Controller described an unsafe condition when the RADAR equipment was released to maintenance with only a few minutes notice.