The current process for tasking MCA helo's, is the ARCC contact the MRCC responsible for the helo, and then the MRCC scramble that helo. The ARCC's role is to allocate the closet unit.
At the moment having no HF in the back of the CHC cabs, works just fine. There has never been a great need for it. Should the winchman require a link call with a doctor then this is possible through the use of the satphone.
In fact i think most current CHC sar flights would prefer not to speak to the ARCC direct.
