I 1998, a handful of SK37s (the two seat trainer variant of the Viggen) were converted into electronic warfare aircraft and redesignated SK37E. One of them, serial number 37811, was also painted grey (all the others kept their woodland splinter camouflage). The red lightning bolt was added when the EW-Viggen (as it was often called internationally) first participated in the annual international EW exercise ELITE in 2003. At ELITE 03, the EW-Viggen gained a fearsom reputation, earning the nickname "the terrorists".
This skin is based upon 37811 when it was based at F21 wing in Luleå, with the callsign "Urban 73".