NEWS | June 4, 2020

SINCGARS: Keep it Cool

Dear Half-Mast,

The unit I’m with keeps our SINCGARS stored in our vehicles (HMMWVs, Bradleys, M1 tanks, etc). The temperatures here routinely hit triple digits and can easily go a hundred degrees or higher inside the vehicles. And the radios often stay there for days or weeks at a time between operations.

Is there something official we can use to require removing the receiver-transmitters from the vehicles and storing them inside to protect the components from heat damage?

Dear Sergeant,

First, we’ll address your question from purely a maintenance perspective.

Radios will always be more sensitive to temperature changes than other Army equipment. Due to the extreme temperatures of your environment (difference between day and night temperatures), it’s a good idea to store your radios in a temperature-controlled environment.

While TM 11-5820-890-13&P (Aug 14), states that the operating temperature is between 32ºF and 122ºF, keeping radios cool or warm when not operating them is a good idea for two reasons:
  1. Hot or cold extremes can result in condensation if the radio isn’t properly sealed. There are rubber seals around the top cover which keeps it water-resistant and somewhat air-tight, but the air already inside the radio contains moisture as well, as all air does. So the hot/cold extremes can cause condensation build-up inside the radio.
  2. Connectors that hold onto the circuit card assemblies expand and contract with the temperature, which sometimes causes failed connections.
Now let’s discuss your question from a policy or standard operating procedure (SOP) standpoint. Although there’s no Army-wide or lifecycle management command policy stating you need to remove radios from tanks or other vehicles exposed to extreme temperatures, it makes sense to do so in order to avoid problems down the road. Work with your unit’s leadership to implement an SOP to make removal of receiver-transmitters routine practice. Carefully think everything through to ensure they’re removed and stored safely and appropriately.