Large Area Smoke Screens in the ETO
The Invasion of Normandy
Almost from the very beginning of their labors Allied planners for the cross-Channel attack contemplated the use of smoke for the beaches in France and the ports that were to be developed there. In 1942 the combined British-American planning organization included an antiaircraft committee which, in turn, had a smoke subcommittee. The logistical computations for the British Haslar generator, the best model then available to the Allies, indicated such large requirements for oil as seriously to limit extensive use of the technique of large area screening. Fortunately, at this time the National Defense Research Committee brought out the M1 mechanical generator, news of which sent a mission hurrying from England to the United States. Colonel Montgomery, the American representative, reported that the new generator was five times as efficient as any existing smoke device. Substitution of the M1 for the Haslar enabled smoke planners to draw up oil requirements which were far more reasonable.1
The development of the new generator prompted attempts by CWS staff officers in England to get a smoke generator company for the theater. War Department inquiries about the requirements for such units got little response from the Eighth Air Force, which came to the conclusion that the advantages of airdrome concealment were equaled or outweighed by the interference of smoke with operations. But SOS authorities in the theater showed interest in smoke as a means of concealing supply installations and later included the ports in
Great Britain through which flowed the build-up of troops and supplies from the United States. Diminishing German air raids reduced theater interest in this type of activity, although during mid-1943 planners envisioned the use of some twenty or twenty-four smoke companies to conceal continental ports once the invasion was under way.2
With the return of General Eisenhower to London from the Mediterranean area in January 1944, planning for the cross-Channel attack began to take final shape. The troop basis for U.S. smoke generator troops now totaled twelve companies, organized into three battalions. Although these were originally listed as SOS units with a primary mission of rear area screening, Colonel MacArthur, CWS representative in the planning group, insisted that one smoke battalion be earmarked for tactical employment with the combat forces.3 And it was to be in this role, rather than through their part in the concealment of rear areas, that smoke units were to make their most effective contribution.
Brigadier G. H. Pennycock, director of chemical warfare for the British 21 Army Group, coordinated Allied smoke screening plans for the initial phase of the invasion. Colonel Coughlan, FUSA chemical officer, was in turn responsible for the operational plans for American forces. One problem which had been troubling First Army, the difficulty of landing the heavy M1 generators on the Normandy beaches, was eliminated almost on the eve of the assault with the arrival of the M2 generator which had a dry weight of only 172 pounds. Smoke troops received the first M2 on 13 May, 7 more on 24 May, So on the 28th, and 27 between that date and 3 June.4
Final plans for the use of large area smoke screens during the cross-Channel attack provided for smoke over the ports of England from which the invasion would be mounted and smoke over OMAHA and UTAH beaches in Normandy. In both cases the screens would be used as a means of concealing activity from German aircraft. The companies of the 24th and 25th Smoke Generator Battalions received the English port assignment; the 23d Battalion, commanded by Lt. Col. William M. Fiske and including the 79th, 80th, 84th, and 161st Smoke Generator Companies, was earmarked for duty at OMAHA Beach, but not
for the first three days of the operation. Chemical decontamination troops, scheduled to go ashore with the initial landings, were at first to use smoke pots and M2 generators to provide any necessary smoke. The 23d Battalion, with two companies on land and two on offshore trawlers, would assume responsibility for the antiaircraft smoke at OMAHA Beach on D plus 3.5
Once these general plans for smoke operations were completed, the units which were to take part could begin realistic training for their projected tasks. The 30th, 31st, and 33d Decontamination Companies received such training and were attached to engineer special brigades for the operation. The 79th and 80th Smoke Generator Companies, designated as the sea group of the 23d Battalion, had to become accustomed to working and living on trawlers. Their offshore employment also presented communications problems which had to be worked out by the battalion. In order to insure the necessary timing and coordination the 23d was attached to the 49th Antiaircraft Artillery Brigade which had control of smoke although subject to the approval of the naval command and the veto of the tactical air command.
The two smoke generator battalions assigned to the English ports naturally began operations before the actual day of the invasion. The 25th, comprising the 85th, 86th, 165th, and 171st Smoke Generator Companies, furnished smoke in the Weymouth-Portland area. During the last part of May the Luftwaffe attacked the area three different times inflicting damage only during raids when the battalion was not ordered to make smoke. The 24th Battalion (81st, 82d, 87th, and 167th Smoke Generator Companies), part of which saw action in the vicinity of Brixham, made smoke on fewer occasions than did the 25th.6
The 33d Chemical Decontamination Company landed on UTAH Beach on D-day with the multiple mission of decontamination reconnaissance, smoke, and CWS supply.7 Although by that afternoon the unit was prepared to provide smoke on call from VII Corps, the German Air Force failed to appear in strength and the need for smoke never materialized. As a consequence, the 33d's main mission became that of supply; the CWS dump maintained by the unit handled over
5,000 tons of CWS Class II and IV supplies during the first three weeks on the beachhead.8
Both the 30th and 31st Decontamination Companies saw action on OMAHA Beach. The former's 1st Platoon landed at H plus 16 minutes in the midst of the most rugged fighting of the invasion with the missions of decontamination, smoke, and supply. At first, the platoon fought along side the infantry using small arms and grenades and later, when the beachhead was secured, it aided in evacuating wounded and in clearing mine fields. During the afternoon the portable generators that had been lost in the surf at the time of the landings were retrieved and put into operating condition. As at UTAH, there were no calls for smoke. The 1st Platoon suffered 25 percent casualties on D-day and was cited for outstanding performance of duty.9 At 1300 the 3d Platoon landed on OMAHA to be joined by the remainder of the 30th Company on D plus 1. A 25-man detachment of the 31st Decontamination Company came ashore at H plus 7 hours on 6 June and was reunited with the rest of the company on the next day. In activities which followed the pattern set by the other decontamination companies, the men of the 31st performed a series of secondary duties in the absence of gas warfare and the need for smoke.10
According to plan, the companies of the 23d Smoke Generator Battalion were to have assumed the smoke mission at OMAHA on D plus 3. The land contingent of the battalion, the 84th and 161st Companies, arrived off the beach on the afternoon of D plus 2 and came ashore that evening. Both companies experienced a great deal of difficulty. Men and equipment became separated; some roads indicated on the map were nonexistent and others were heavily mined or subject to enemy fire. Fortunately, few German planes appeared over the area and smoke was not required.11
The 79th and Both Smoke Generator Companies, with their men and M1 smoke generators aboard thirty of His Majesty's trawlers, on 9 June arrived off OMAHA Beach, where they served as the offshore element of the 23d Battalion smoke installation. But they received no requests for smoke. The great storm of 18-21 June wrecked some of
M2 SMOKE GENERATOR
the trawlers and others returned to England for repair and refueling, never to return to OMAHA. Some offshore smoke troops did provide screens at Port en Bessin where both British and Americans were bringing ashore fuel oil and lubricants. Here, in coordination with the British, the smoke trawlers stood ready to provide screens at twilight and during nocturnal red alerts as long as this important facility seemed threatened.12
During the critical period while the Allies were fighting to secure a firm foothold in Normandy, the landing beaches were virtually free from bombing from the air, and the need for beachhead and port screening did not materialize. Equipped with M1 generators, the companies of one smoke battalion did take positions around Cherbourg and remained on the alert until mid-August, although the need for smoke never arose. Under circumstances such as these, smoke units received
unrelated secondary missions, mostly involving trucking duties. Consequently, when an opportune time did arise for using smoke in close support of tactical operations the companies were busy performing other tasks.