NEWS | June 3, 2021

M139 Volcano: Hand Control Unit (HCU) Replaced by New HCU Cable Set

M139 Volcano
Photo by Staff Sgt. Gregory Stevens
If you plan to use your unit’s M139 Volcano on HEMTTs, you need to know about a major change to the hand control unit (HCU).

The Volcano’s HCU has two (2) NSNs: 1095-01-388-4846 and 1095-01-271-8055 (legacy). Both are being replaced by a new HCU cable set, NSN 1095-01-689-2286.

The new HCU cable set has four (4) cables that disconnect from one another. The cable NSNs are:
  • NSN 1095-01-689-2300
  • NSN 1095-01-689-2309
  • NSN 1095-01-689-2324
  • NSN 1095-01-689-2346
You can order the NSNs separately to replace damaged cables or, if needed, buy the complete HCU cable set. Either way, getting this new HCU cable configuration set is easy and will be the only cable set used on the air and ground volcanoes eventually.

The M139 Volcano Program Management Office is developing TB 9-1095-208-23-1 for the Volcano that provides specific guidance for installing the cable set on your HEMTT prime mover. TM 9-1095-208-23-1&P (Jan 06) is no longer supported and being re-written. Make a note until the TM is updated.

These changes to the HCUs and future Volcano improvements will increase safety to Soldiers and enable them to stay in their vehicles through the use of this new cable configuration.

To request more Volcano support information, email TACOM’s Close Combat Systems team: