German E-Boats: Why So Dangerous?

Dangerous Weapons That Were Hard to Counter

A Kriegsmarine Schnellboot (S-boot or E-Boat) fires a 21 Inch (533mm) torpedo.

The "War of the Boats" was a long battle between the Allies and the Axis, primarily but not exclusively in the waters of the North Sea, the English Channel, and the Mediterranean. It involved repeated clashes between fast, heavily armed, and relatively small German E-boats and similar British watercraft. This was a deadly battle that claimed a lot of ships, lives, and freighter cargo.

"E-boat” was the generic Allied designation for Kriegsmarine motor torpedo boats (MTBs) and similar craft. The “E” stood for “Enemy.” The Germans called them Schnellboot, or S-Boot, meaning simply "fast boat." They posed a real danger far longer into the war than some other notorious German weapons. Let’s explore why that was.

An E-boat unloads a mine in the Baltic.

What Were E-boats?

One of the limitations of the Treaty of Versailles was that it limited certain types of German weaponry but not others. One oversight was permitting the Germans to develop boats smaller than destroyers as weapons.

Accordingly, the Reichsmarine (later Kriegsmarine) began developing E-boats began at least as early as 1929, long before Hitler came to power. The Germans used this time wisely to refine designs. For instance, they found that using diesel engines rather than less efficient gasoline engines provided range advantages. They also learned how to use the Lürssen effect, which provided a speed advantage by installing by two small rudders mounted on each side of the main rudder and turned outboard. These insights led to both speed and stability enhancements.

The first S-boat (later named S-1) was built in 1930 and provided the foundation for further refinement. Over time, the 35-meter (114-foot) S-boats could achieve well over 40 knots and over 700 nautical miles (810 miles or 1,300 km)., quite impressive for the time.

A Siebel Ferry on Lake Ladoga, 13 August 1942 (SA-Kuva).

The E-boats were part of an assortment of smaller Kriegsmarine craft such as the Siebel ferries. Siebel ferries, designed by a Luftwaffe engineer Colonel Fritz Siebel, were large catamarans. They were not particularly fast (only 10 knots) but were powerfully armed with an assortment of 88-mm Flak guns and 37-mm artillery. These 30-foot-wide vessels could be quite powerful and lethal when you got too close. If you chased an E-boat too far, you could run into heavy artillery in a hurry.

Two E-boats - S-204 and 2-205 - after their 13 May 1945 surrender at Felixstowe (Archiv Roderick Timms).

Why Were the E-Boats Such a Problem?

Weapons are only feared if you don’t have a good counter to them. Someone with a bow and arrow is not a big problem if you are riding in a tank. This leads us directly to our answer of why the Allies had such problems with E-boats.

The British were extremely proud of the Royal Navy and lavished vast sums of money on its big ships (quite well spent, as it turned out) during the interwar years. They also spent a great deal of effort developing the Fleet Air Arm, also to good effect. However, they were completely blind to the dangers of small watercraft until the threat from Germany began to reach crisis proportions in 1935. As we saw above, this was a number of years after the Germans began intensive development of their own fast boats.

Coastal Forces had existed during World War I but then was disbanded. Even when British attention returned to this type of warfare in 1935, the initial emphasis only was on designing boats for the high-speed rescue of downed aircraft crew. The first designs were 60-foot wooden boats built by the British Power Boat Co.While they could make 36 knots, they were hard to handle in poor weather - and there was a lot of poor weather in the North Sea. Coastal Forces began working on new designs, but they were always far behind the Germans.

Vosper-class MTB 382 © IWM (FL 8592).

While far behind, the Royal Navy Coastal Forces were not out. British designers learned quickly and came up with adequate designs. During the war, the British began creating a force of  MTBs of different sizes. Vospers & Company in Portsmouth built 73-foot (22 m) MTBs. These Vosper-class boats were powered by three 1400 hp (1044 kW) Packard gasoline engines. The first model, type I, had four 18-inch torpedo tubes and an Oerlikon 20 mm cannon along with Vickers K machine guns.

A Fairmile D-class Motor Torpedo Boat.

The classic Coastal Forces vessel, though, was the Fairmile “D” class MTB (known as “Dog” boats). They were powered by four 4800-hp Packard engines. These began to appear in 1942 and solved many of the problems of the earlier Coastal Forces boats. However, most neutral observers would conclude that the E-boats were always superior. Their diesel engines posed a low fire risk compared to the Coastal Forces MTBs, they were fast, and they could travel farther. It took over another decade, long after World War II, for Coastal Forces to begin using diesel engines.

Waiting so long to reinstate Coastal Forces led to other problems. A Coastal Forces Periodical Review of 1945 noted in refreshingly candid language:

We started the war with almost complete lack of experienced MTB officers… and there were no senior officers who could train the young ones; there as no considered amalgam of doctrine and experience. The navy generally knew nothing about the boats.

The navy is not like other services in that change takes a long time. This hurt the Germans the most, of course, because they were unable to develop a competitive surface fleet due to the long lead times involved. However, in this area, it was the British who had the problem. Lack of effective boats and the men to crew them was not a problem that could be quickly rectified.

HMT Wallasea (T345), sunk by E-boats off Mounts Bay on 6 January 1944.

The Battle

The Allies certainly learned to respect the danger of the E-boats. During the war, E-boats sank 101 merchant ships totaling 214,728 tons. In addition, they sank a wide variety of warships and smaller craft. Many of these freighters were sunk off Suffolk and Norfolk, England, where England bulges out into the North Sea. This geographical feature forced local convoys further east into a vulnerable position. Thus, the highest degree of danger was concentrated in a specific area and there was no way to eliminate that geographical reality. This heightened the fear when passing through this danger zone.

USS LST-289, heavily damaged by E-boats during training for D-Day on 28 April 1944, moored in Dartmouth Harbor, England.

While not a routine occurrence, battles between E-boats and Coastal Forces MTBs took place. They tended to be wild affairs, fought by moonlight and usually around a convoy of freighters. Attacks tended to happen during the night because E-boats wanted to avoid daytime attacks by warplanes. However, battling Coastal Forces MTBs was not the E-boat crews' objective - sinking freighters and larger Royal Navy ships was their goal. They were good at that.

HMS Exmoor, sunk by an E-boat on 25 February 1941.

As examples, among the E-boats' larger successes was the torpedoing and sinking of L-class destroyer HMS Lightning (G55) on 12 March 1943 about 35 nautical miles north of Bizerte, Tunisia. Another success was sinking Hunt-class destroyer Exmoor off Lowestoft on 25 February 1941, with the loss of 104 lives (some accounts claim this sinking was due to a  mine, night actions were very confused). A third success was the sinking of Hunt-class destroyer HMS Penylan on 3 December 1942 while escorting convoy PW-257 five miles south of Start Point.

So, destroyers were fair game for E-boats, able to sneak up on them during confused night actions and hit them with torpedoes. Larger Royal ships usually had escorts and were harder to get to, plus they tended not to operate in the "narrow seas" favored by the E-boats.

The course of the overall war increasingly favored the Allies, of course, and that applied to the “War of the Boats” as well. Called derisively early in the war “Costly Farces,” Coastal Forces gradually redeemed its name and achieved the upper hand. However, the E-boats remained dangerous until their bases were overrun.

Another view of LST 289 after being attacked by E-boats during Exercise Tiger on 28 April 1944 (Exercise Tiger Trust).

One of the E-boats' most savage victories took place on 28 April 1944, when E-boats based at Cherbourg intercepted a convoy of eight landing craft (LSTs) engaged in landing exercises (Operation Tiger) preparatory to D-Day. Through a number of security lapses and unexpected incidents, the convoy was almost defenseless. The E-boats sank two LSTs and badly damaged two others, killing 749 U.S. servicemen being carried as passengers (551 United States Army and 198 United States Navy). This was the infamous “Slapton Sands” incident that was covered up for months by the Allies. In fact, it was so embarrassing that some details remain classified in the 21st Century.

A Kriegsmarine E-boat.

Conclusion

The Germans held an advantage in “The War of the Boats” that only disappeared as the overall Axis military position reached its terminal phase following the D-Day landings on 6 June 1944. This was due to a long head start in the development of this type of warfare by the Germans, including important work done long before Hitler came to power. The British were guilty of ignoring an emerging area of warfare because they were focused on other areas, such as big ships and aircraft, and they paid the price.

The Royal Navy did not adopt diesel engines, used by the Kriegsmarine during World War II, until the Dark Class boats entered service beginning on 28 October 1954. Here, HMS Dark Aggressor P1102 fires a full salvo of four torpedoes during an exercise (photo by Lt. Sugden, RN. It appeared in the Sauders Roe Magazine, "Saro News").

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