MS requires 155.34 in all medevac aircarft

https://www.healthyms.com/msdhsite/_static/resources/8155.pdf

SOURCE: Miss. Code Ann. §41-59-5 Rule 3.7.6 Communications Equipment:
on the aircraft and ambulance – All communications must be maintained
in full operating condition and in good repair. Radios on aircraft (as
range permits) must be capable of transmitting and receiving the
following: #21600 1. 2. 3. 4. Medical Control Communications: The
licensee shall have a means of providing communications between the
aircraft, the coordination point, medical control personnel and other
agencies by telephonic or radio as appropriate. This shall be
accomplished by local or regional EMS radio systems; and/or radio or
flight phone as available inboard the aircraft. All aircraft shall
have 155.340 statewide hospitals net available for air crew member(s)
in the patient area. Communications Center Air Traffic Control
Emergency Medical Services.

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