RichTO90 wrote: Carl Schwamberger wrote:
On a slightly more serious note I wonder if the two tank battalions had been equipped with predominately 105mm cannon would their fires have been noticeably more effective? I'm thinking smoke ammo as well as HE & AP types.
Smoke? No, the intended "Smokers" (LCP fitted out with chemical smoke generators) on all the beaches were discontinued because the wind was too great and it dispersed too quickly. The AP round for the 105mm was a HEAT-type and at that time had little effectiveness versus reinforced concrete, while the HE probably would only be marginally more effective. None of them were seriously effective against the big gun emplacements except those that were incomplete unless they hit the firing slit...and even that wasn't necessarily a guarantee.
Both the HE shells for the 105mm howitzer and the 76mm high velocity gun were found to be superior to the 75mm HE shell in dealing with concrete and masonry in the March 1945 battle for Manila, during combat in at the old Spanish fortress of Intramuros.
The 105mm HE shell with concrete penetrating (CP) fuse had three times the HE payload of a 75mm HE shell with CP fuse and and the 76mm's higher velocity let it get it's smaller payload of HE farther into the structure of concrete to more effectively shatter it.
The superiority of the 76mm in the concrete busting role was noticed as early as Nov 1943 with Japanese reinforced concrete positions at Makin via the combat experiences of the 193rd Tank battalion -- which was using M-10 tank destroyers in lieu of M-8 75mm SPM or M-7 105mm SPM in its assault gun platoon -- and was later confirmed in the July 1945 weapons tests at Ft Hood versus replica Japanese cave positions in the conventional weapons half of Operation Sphinx.
As for smoke at Omaha, this shows a point I keep running across with Ike's crew. They only learned from their own direct experience and discounted the combat experiences of other American field commanders. If they didn't personally see it themselves in the Louisiana Maneuvers or North African fighting. It didn't exist for them.
We saw this with General Cota and his emphasis on LVT's which Ike's crew disregarded and we see it again with the inadequate smoke plans on Omaha beach. Salerno, Anzio and the Operation Dragoon landings were all far superior in their use of large scale smoke screens than Ike's show on Omaha beach.
The following passage is from the CHEMICALS IN COMBAT US Army green book on the August 1944 Operation Dragoon landings. It shows how US Army Chemical troops coming ashore with, or riding on, DD-Tanks in Southern France screened the beaches there:
The smoke troops again were to come from a chemical decontamination
company, this time the 21st. On 25 March 1944 the unit's 2d
Platoon moved from Palermo to a beach near Oran, where it was attached
to the 40th Engineer Combat Regiment to prepare for the
invasion. Practice in assault landings and in the erection of beachhead
smoke lines constituted the bulk of this unit's training. In turn, the
Engineers gained the experience of working in a haze limiting visibility
to fifty yards. By June the platoon rejoined the 21st in Italy where it
passed on its recently acquired amphibious experience to its three
During the last weeks of July and the first week of August the three
divisions which were to make the assault and their supporting troops
underwent brief but effective practice for the appointed task.*^ The
culminating point was a full dress exercise in which the conditions
expected on the beaches of southern France were realistically duplicated.
Live ammunition, beach obstacles, and smoke screens helped to achieve
The I St Platoon, 21st Decontamination Company, received an extra
amount of training because the 3d Division had detailed plans for the
use of ground smoke during the initial phases. The additional work
for the platoon, and for a detail of two officers and thirty enlisted men
from the 3d Chemical Mortar Battalion which augmented the division's
smoke troops, was aimed at producing physical hardness, self-reliance,
and proficiency in tactics of the infantryman.
The 3d Division's target area was the St. Tropez Peninsula. Elevations
here reached 1,000 to 1,500 feet, providing the defenders with
excellent observation of the sea, the beaches, and the narrow strip of
wooded dunes. The 3d Division's assault areas on the peninsula, designated
Red Beach and Yellow Beach, were both flanked by capes, a
situation which enhanced the possibilities of German observation and
provided the motive for the flanking screens of the attacking force.
But if the terrain was unpropitious, its defense was another matter.
Intelligence sources indicated that the enemy would not defend the
area too strongly because of commitments in northwest France. Moreover,
the rather skimpy fixed defenses of the area were manned by non-
German and limited service troops.^*
Preceded by heavy naval and air bombardment the VI Corps landed
on 1 5 August against light resistance. During the actual assault the
Navy used smoke only in the 3d Division sector. Here smoke pots and
generators in landing craft screened the flanks of the boat lanes and
concealed incoming craft from enemy fire. Each of the four smoke
details, two per beach, was to land at H-hour in an LCT. Training
trials had demonstrated that under favorable conditions the detachments
with their allotments of 1,200 M4 smoke pots could unload in
about five minutes. It was hoped that the final stage of the trip to
the beach would take place in specially buoyed medium tanks which
were on the LCT's. If this were not possible the pots were to be
floated ashore in rubber boats, or, in an extreme case, the packing boxes
with the pots enclosed could be tied in tandem and towed ashore by
The smoke detail on the left flank of Red Beach was led by Lt.
Frank J. Thomas, commanding the 1st Platoon, 21st Company.
According to plan, four amphibious tanks carried the men across the
beach to the railroad about 150 yards beyond. Fanning out to four
positions at l00-yard intervals, the detail began operations within ten
minutes of landing. The smoke line was gradually pushed inland to
a road 250 yards from the beach. Until this time the smoke troops
had not received enemy fire, but now mortar and small arms fire caused
one casualty. No casualties were suffered in the heavily mined
woods through which the smoke troops passed to reach the road.
The detachment from the 1st Platoon, which landed on the right
flank of Red Beach, was led by Capt. Sam Kesner, assistant chemical
officer of the 3d Division. For some reason the landing craft dropped
its amphibious tanks some 1,000 yards from shore. Consequently,
Kesner's party, which remained in the LCT, had to unload Its pots
the hard way. Some were thrown into two 6-man rubber boats and
towed to the beach. The rest of the smoke munitions were tossed overboard
and floated ashore in their crates, an expedient made necessary
by the pressure of enemy small arms fire. The situation was made more
difficult because the LCT had landed 400 yards to the right of its
assigned area in order to avoid mines. The smoke plan called for four
positions on the beach, a number soon increased to twelve because of
the adverse winds. The smoke detail soon pushed inland about 100
yards, suffering four casualties in the early hours.
The two smoke details in 3d Division's Yellow Beach came from the
3d Chemical Mortar Battalion. Each of the one officer-fifteen enlisted
men details landed at H-hour, meeting conditions not unlike those
found on Red Beach. Because of the offshore mines, the LCT carrying
the right flank party beached south of the assigned area. The group
worked northward into position using smoke grenades for concealment
from small arms fire. Opposition was heavier near the center of the
beach but the smoke screen helped to eliminate observation, with the
result that enemy fire became erratic, ceasing about H plus 30 minutes.
The total length of the two screens on Yellow Beach was 2,000 yards.
Although the smoke mission for Dragoon was extremely well
planned and executed there was still room for improvement. Captain
Kesner felt that the eggs should not have been placed in so few baskets
that a larger number of craft should have carried the members of the
smoke details during the assault. In this way the sinking of any LCT
would not have been an irreparable disaster. Maj. Albert L. Safine,
Chemical Officer, 3d Division, suggested that in landings where enemy
opposition would be substantial (resistance at Dragoon was weak)
the smoke detail should land at H plus 30 and that the equipment
include amphibious mounted generators.
Compare that plan as executed with Omaha Beach!
The issue with the failure to use large scale smoke screens adequately at Omaha seems to be bound up with pre-war US Army internal budget politics and existing racial attitudes towards black -- called Negro then -- troops.
General Leslie McNair was a part of a special board seeking budget cuts to save the US Army from the Depression era cut backs. He recommend the elimination of the Chemical Warfare Service.
The House Armed Service Committee chairman whose district the Edgewood Arsenal was in told the US Army to pound sand. McNair and the rest of the Army remembered this, and when the Army expanded in 1940-late 1941, the CWS got nothing.
It took the Japanese using mustard gas on the Chinese Nationalist troops in the summer of 1941 to get the FDR Administration to throw a lot of money at the CWS.
By then, it was too late for any smoke generating troops to be available for the Louisiana Maneuvers. And since no one ever used smoke troops, they were given a very low manpower rating by both the AGF and ASF, and thus were assigned a lot of black troops. Fifteen of the Army smoke generator units (not counting the decontamination companies) used in the ETO and MTO theaters were black.
Smoke Generator companies were also assigned a very low transport rating for North Africa, so the few smoke companies sent there arrived late and were were used to guard sea ports against German air attacks.
Later, when black smoke generator and chemical decontamination companies were sent to Europe, they were turned into general labor troops.
And even when black smoke troops were used as they were designed to in Italy and succeeded, Ike's crowd ignored their successes. Once Anzio turned into a debacle, any combat experience from it was "unclean."
THE EMPLOYMENT OF NEGRO TROOPS
http://www.history.army.mil/books/wwii/ ... pter20.htm
Certain units, like the engineer dump truck companies, always in demand, always used, and almost always Negro, were considered of great value by the using commands and were therefore well and fully employed; others, like chemical smoke generator companies, also with a heavy Negro representation, were less generally used for their primary missions, often being put to guarding warehouses and prisoners and operating depots. When formally converted to other missions, units developed high efficiency in their new tasks when they were convinced that these tasks were of more obvious and immediate value than their former assignments. Such was the case, for example, in two quartermaster service companies whose personnel came from disbanded units. These men learned rapidly, gaining "in efficiency until approximately seventy per cent were performing technical duties and only thirty per cent were performing general service duties."1
Occasionally, special purpose units were employed in landings. At Salerno, the first Mediterranean assault landing to use smoke screens extensively, Navy and Army units laid screens on and off the beaches over an area twenty miles long to protect landing craft from enemy fire. In the D-day assault on 9 September 1943, a detachment of the 24th Chemical Decontamination Company, equipped with M 1 smoke pots, and Navy personnel with generators mounted in boats screened the Paestum beaches where boats were being unloaded. During the following days the unit operated thirty-six naval mechanical generators ashore. The men laid a smoke haze daily at twilight to conceal anchorage and unloading areas from enemy bombers and screened the beaches during alerts. Smoke generally covered an area of twenty to thirty square miles. Not a single ship in the smoke cloud at Paestum was hit by enemy bombs.120 The 24th, with other smoke companies, moved to Naples to maintain the smoke screen there. For the Anzio landings on 22 January 1944 the 24th was attached to VI Corps to provide smoke as needed. Equipped with eight Navy generators and a quantity of smoke pots it went ashore, laying its first screen on 24 January. More generators were brought in later. A British smoke unit took over the operation of smoke pots on 8 February, leaving the 24th free to operate mechanical generators, now thirty-six in number. These units ran the antiaircraft smoke screen until 24 February, when the 179th Smoke Generator Company, a white unit, arrived to extend the line to Nettuno. At Anzio, the smoke operators lived the life of front-line infantrymen, with foxholes and caves dug, the Fifth Army chemical officer reported, so that "a German shell would have to execute a corkscrew to get at them." 121 For its work at Anzio the 24th Decontamination Company received one of the first four Fifth Army plaques and the first awarded to a chemical unit. This company later operated chemical depots.