What was a guard channel?

[Sparrowhawk]

On November 21, 1967, we were in heavy combat on the ground, near Finger Lake, Arizona territory Btn the Via Gia and Song Thu Bon rivers, near football Island/Liberty Bridge.

During that time all we had was a prc-25 radio so we couldn't communicate with any bird dog or huey choppers, but we could with medevac choppers?

Trying to remember why.

We didn't have a AO with us, did he carry a different radio or was it just different frequencies?

Just trying to remember.:confused:

Thank for any response.

Cook Barela, 1st platoon, India Co. 3/7 RVN 67-68

[Allyn Hinton]

PRC 25 is a FM radio, and you should have been able to talk with any helo if they were on your frequency. Fixed wing aircraft had UHF radios, and AO teams should have had a ground UHF to call in air strikes.

I know in the UH-1E we had four radios:
FM radio for comm with ground units.
UHF radio for comm with other aircraft and air traffic control.
TACAN and ADF radio for navigation.

I know it was a common practice for us to tune to the command frequency of the ground unit in the area we were in at the time. The problem is the aircraft and ground unit have to be on same frequency, and the FM being a line of sight radio the range is limited.

[Jim Wilkening]

The aircraft emergency frequency (also known as the guard channel) is a frequency used on the aircraft radio band reserved for emergency communications for aircraft in distress. The frequencies are 121.5 MHz for civilian, also known as International Air Distress (IAD) and 243.0 MHz for military use, also known as Military Air Distress (MAD). Both are in use at the international level.