"Nothing that results in human progress is achieved with unanimous consent."
Christopher Columbus
When U.S. Army light infantry forces deployed in support of UNISOM II in Somalia, they went without light armored fighting vehicles (AFVs) and a major caliber gun system because these weapons are not in their force structure/design. Having such assets became a political issue and men died needlessly because of it. Light Infantry needs at least a limited armored assault gun capability. The M113A3 with a 106mm is a reasonable solution. No need to go into details about modular kits or availability as Ernest Hoppe states in the Jan-Feb '97 Infantry magazine. It is a proven system, and well-known. U.S. Army Combat Engineers who already have M113A3s--- could become the heroes that can save the day here by mounting M40A2 106mm RRs, but the engineers might be simply be left behind in the motorpool, just as Custer left behind his Gatlings. The solution must be to change the mindset of the Infantry.
We need to convince the infantry community of the need for an armored assault gun to support its light, early-entry infantry. The M113A3 with 106mm is a solution. Mike Sparks' comparison of the 5-ton truck's weight being equal to the M113A3 in the Nov-Dec 1996 Infantry magazine is an excellent point. If Light Infantry can take along 22,000 pound trucks they can take 11-ton M113A3s with 106mm RRs to the battlefield, which must be ORGANIC to their force structure so not to be vulnerable to the political chopping block.
In fact, the Canadian Army has devised a ZERO COST means to take the M40 series 106mm Recoilless Rifle and weld locks and a wheel track to the upper deck of its M113s so it can stay connected with its tripod for ground mount capability. Special thanks are in order to Major A.D. Woolley and LCol (ret) K.H. Bettes of the Canadian Armed Forces, who did this detailed research we now know exactly how they did it! Their work holds the key to a rapid fix to this problem using M40A1/2 106mm RRs and M113A3s already in the U.S. Army inventory.
The Armoured Defence Platoon commanded by the then Captain Bettes for 3 Mech Commando in Germany trialed this concept around 1971. The AD platoon included 12 x 106 M113A2 tracks plus 6 with 2 x SS-11-B ATGMs. They were only in service in this form for a few years when both were replaced by TOW ATGMs and the 106s were sent to the reserves to be used jeep-mounted.
The mount is positioned over the rear hatch which cannot be opened (very far) while the gun is mounted. The rear legs are positioned as far to the rear of the deck as possible and the front wheel sits behind the commander's hatch. Although the mount is straight in line with the body of the APC, the barrel is angled to the right over the engine.
There is a triangular travelling lock mounted to the right of the commander's hatch and just behind the engine grating. This is designed to fold back flat when the gun is in use or dismounted. It must secure the gun before the vehicle moves. The front wheel of the mount fits into a short track mounted behind the commander's hatch. This track was made from sheet steel bent twice to form the sides and bottom. A hole was drilled in the sides to accomodate a locking pin (about 3/4 - 1" in diameter) which passed through a matching hole in the wheel of the mount. The holes would line up only when the wheel was rotated so that its hole was at the lowest point. The rear legs sat in short brackets designed to prevent their horizontal movement. The rear latching mechanism was designed to grab onto the upper rear corners of a M38A1jeep--but I believe that there was a folding bracket made from bar stock which would flip up to be engaged by the handle catches. In some of the photos it looks like there is a clamp or strap about halfway up the rear leg to prevent the handle from accidentally coming up and disengaging the latch. The 106 was not modified (except for the hole drilled in the wheel) for mounting on the M113 APC and retained it's ability to travel on the jeep, or today's HMMWV or ParaGator.
The crew normally consisted of three - gunner, driver and loader. This contrasted with Jeep dets which also included a det commander. In action, the APC was positioned so that the right front corner was pointed toward the enemy. This allowed the vehicle to present an angled profile and allowed more room on the rear deck for loading. As the breech overhung the back of the vehicle, loading was difficult. By angling the gun, the loader had a little more room. Ready ammunition was carried in crates on the rear hatch (no special brackets were used, it was just strapped down) and the remainder inside the APC. In action, the rear ramp was normally open. The antenna was mounted on the left centre mounting unit and extention cords for the gunner's and loader's headsets were required.
As you can see in the pictures, the APC will swim with the 106 but tends to be heavy in the right front. this can be compensated for by redistributing the ammunition inside.
I'll give a quick description of the photos to point out the pertinent details.
- side view. The travelling lock is down so that the gun can rotate. You can see the relative position of the mount to the body. The black diagonal thing behind the driver's elbow isn't part of the mount but is the commander's hatch cover.
- maintenance after an exercise. You can see the travelling locks are up. Note that the barrel will clear the commander's hatch. The breech in the left foreground gives some idea of how far it overhangs the rear of the vehicle.
- good shot of the travelling lock
- on the move in Germany. This shows the usual positions for the driver and gunner - the loader would be inside.
The amphibious M113A2/106 combination: the first swim trials. On the picture above, it shows the rear mounts and position of the wheel. I know, it looks like it is off to the right of the commander's hatch, but the person I contacted believes that it was behind. The next two pictures are front views which show the angle of the gun in the travelling position. g shows how the APC tends to list to the right front (or is it the starboard bow?) It also shows clearly how the wheel is behind the hatch. In the later pictures there is an enlargement of the wheel mount shown . I'm afraid that the resolution isn't what it should be but it does show the idea.
2. Where should the fire support go?
What level (echelon) of fire support? For example, should we have a platoon of these vehicles per light infantry battalion (part of the HHC)? Should we have a company in the infantry brigade? I could also see an excellent argument for a battalion of these, perhaps a 50:50 mix with revamped M113A3 ITVs (Hellfire ATGM turrets or 120mm direct fire mortar turrets), to replace the Sheridans of the 82nd Airborne's 3rd/73rd Armor tank batttalion. This Battalion could come from the 2nd ACR at Fort Polk, LA an integral part of the XVIII Airborne Corps. The expert logisticians will have to figure a lot of this, but there are several reasonable alternatives.
3. Battle woes
The Mogadishu fiasco, Panama, and even Grenada, are specific examples where light infantry got pinned down by enemy fire and was not able to regain freedom of maneuver until vehicular fire support was brought to bear on the enemy. How did we got into this mess?
We lost organic firepower in light units when we went to the LID structure, the elimination of M551 Sheridan, cancellation of the M8 AGS, and retired 90mm and 106mm Recoilles Rifles in favor of essentially single-purpose TOW ATGMs: kill enemy tanks, The latest TOW IIB with its fly-over feature to attack armor from the top is worthless against targets head-on even if the launcher can get into distant enough firing position to acquire and track the missile to target, which is unlikely in a close urban fight with targets under 200 meters away.
Consider how much was LOST to light infantry. The pre-Bradley mech organization had 3 platoons of M113 tracks, each with a .50 caliber heavy machine gun, a company mortar platoon of 81mm M125 tracks, and two x 106mm anti-tank M113 tracks (later replaced by TOW, then ITVs). This M113 force could swim across lakes/rivers at will, be heli-transported and airdropped to any spot along the battlefield without Combat Engineers having to build bridges and improve roads as they must for the 33-ton Bradley IFV and 70-ton Abrams MBT. If the Indian Army had to take 3 days to cross a river like we took to bridge the Sava, it would have lost the 1971 war. U.S. Army Combat Engineers are now equipped with M113A3 tracks just so they can have the superior mobility needed to move ahead of the Bradley-Abrams Heavy force to pave the way for them---why not just have light infantry move out in the M113A3s in the first place?
Even the old infantry (light) [C-series TO&E] battalion, had the same company 81mm mortars in 3/4 ton, 5/4 ton trucks, M561 Gama Goats, and 106mm RRs (later TOWs) on M151 jeeps for adequate firepower. We EMASCULATED the light infantry battalions when we went to LIDs by only having a few HMMWVs with TOW ATGMs and heavy machine guns available----nothing to blast enemy strongpoints-buildings with.
4. The EMASCULATION of the light Infantry.
Light infantry are the victims here of poor force structure-design, better suited to a close-terrain supporting role in an armor confrontation on the Fulda Gap in Germany than a firefight in the far eastern jungle or third world country urban battle. The restoration of all-purpose firepower in the form of 106mm RRs and light AFV mobility from the M113A3 can be added to our LIDs without changing force structure airlift requirements by replacing the currently used same size-weight 2.5/5 ton trucks with the former. These improvements add GREATER utility to the light infantry in an open terrain anti-armor fight, making it possible to shuttle anti-tank teams with heavy to manpack Javelin fire & forget ATGMs into cold-hot firing positions protected from probing enemy artillery fire. The M113 vis-mod OPFOR at NTC is a model of light infantry in tracks contributing to the anti-mech fight. A modest number of M113A3s with 106mm RRs in the LID force structure will solve the "Custer tendancy" and keep the desirable closed terrain fighting capabilities of the Light infantry intact.
U.S. Army Reserve LTC writing to the 1st TSG (A)