ZSE Controller described an airspace incursion event into R6714 involving YKM military fighter departure aircraft assigned the Yakima 5 SID; suggesting the SID not be assigned to high performance aircraft.

Narrative

Yakima Approach called the D-Side and coordinated the departure of three Fighters off of KYKM with an unrestricted climb to FL230. The Yakima Firing Center; R6714; was in use at the time from FL290 and below with aircraft operations. The flight plan of the RIVER11 flight was YKM; J20; OCS then somewhere else. Approach assigned the flight the Yakima 5 departure off of Runway 9; which specifies a climbing left turn back to the YKM VOR and then outbound on the YKM 284 radial before preceding on course. The flight departed and checked on with me 'out of 16.5 for FL230.' Because of the excessive vertical rate; I did not see the Data Block tag up to the target (or even see a target for 10-15 seconds). The lead pilot stated that they were outbound on the 284 radial and looking for direct (direct GLEED; we realized after). He stated that a 090 heading would put him back direct to join J20. When I first saw the Beacon Code; the target was less than the minimum from R6714 (three miles due to the aircraft operating in there). I immediately asked the flight lead to verify his position; and he said he was on the YKM 284 radial. However; his Beacon Target was approximately on the YKM 030 radial and very close to R6714. I issued a turn to heading 180 to get him away from the restricted area; and he responded and was soon clear. I then issued resume on course. The main issue here; is that I don't feel that the Yakima 5 Departure accurately keeps aircraft away from R6714. We don't normally notice when approach assigns the departure since the altitude is in their airspace; but this situation was different since the flight had an unrestricted climb to FL230. The supervisor called approach to find out what happened. We weren't aware that the flight had been assigned the departure. For all we knew; they were climbing out on course. Approach said that they had gone over this before with their local FSDO who claimed that the departure procedure was correct and kept aircraft clear of the restricted area. Since we did not have RADAR on the flight when they checked on and the aircraft were already on the procedure; it was too late to do anything to correct them. Recommendation: don't use the SID; or alter it for military; especially the fighters.