In August 1943, the most fierce battle took place in the Caribbean between aviation and underwater fleet. Powerfully pounded "Browning" of the 50th. of caliber, in response to them flurry of flurry lines of Flak anti-aircraft guns rushed, columns of water rose every minute behind the stern of the boat. The planes passed on a shaver, shooting a submarine from machine guns and dropping tons of depth bombs on it - the battle broke out in earnest.
To the surprise of the Americans, U-615 did not try to dive or throw out the “white flag” - the helpless boat with a discharged battery only increased the course and headed for the open ocean, the deck crew rushed to the anti-aircraft guns. And then it began!
The upgraded U-bot with enhanced anti-aircraft armament turned out to be a “tough nut”: instead of the 88 mm gun removed from the gun, a set of automatic anti-aircraft guns was installed on board the boat, providing circular firing at air targets. The first round ended in a draw - stitched through an anti-aircraft line, the American PBM Mariner flying boat began to smoke and fall into the water. But the hail of dropped depth charges did its job - the damaged U-615 lost its ability to sink.
The Liberator shoots German Y-bot machine guns from 12,7 mm machine guns
Over the next 24 hours, the submarine beat off the 11 attacks of American aircraft, but, despite heavy damage and the death of the commander, continued to stubbornly move toward the open ocean, hiding from the enemy in fog and rain charges. Alas, the wounds were fatal - by the morning of August 7 the pumps were out of order, the battered submarine slowly filled with water and went to the bottom. An hour later, the 43 man from the U-615 crew was picked up by an American destroyer.
Captured U-615 Submarine Crew
U-848, commanded by Wilhelm Rollman, was equally hard killed - an IXD2-type submarine lasted 7 hours under incessant attacks of Mitchells and Liberators from Ascension Island. In the end, the U-848 submarine was sunk; Only one submariner, Oberbotsman Hans Schade, was rescued from her crew, but he soon died from his wounds.
Among the submarines were real champions, for example, the U-256 submarine, which shot down four enemy aircraft. Three aircraft recorded at his own expense U-441, U-333 and U-648. U-481 anti-aircraft gunners shot down the IL-2 attack aircraft over the Baltic Sea - the only loss of Soviet aviation from the fire of German submariners (July 30 1944 g).
Among the Allied aircraft, the B-24 Liberator naval patrols (the four-engine version of the Flying Fortress) suffered serious losses — altogether during the 25 war of low-flying Liberators, victims of anti-aircraft guns of German U-bots.
PB4Y-1 long-range maritime patrol aircraft, also known as Consolidated B-24D Liberator with additional bow turret
In general, the open battles of German submarines with aircraft were more likely episodic - the sailors reluctantly entered into a firefight, preferring to dive in advance and disappear into the water column.
The submarine had never counted on an open confrontation with aviation — the submariners had a completely different tactic based on stealth. A limited number of anti-aircraft guns, the lack of automated fire control systems, inconvenient conditions for the work of calculating guns, a strong overwhelm and instability of the boat, like an artillery platform - all this put the boat in obviously unprofitable conditions compared to an airplane hovering in the sky. The real chance of salvation was given only by the speed of the dive and the earlier warning about the detection by the enemy.
In terms of creating warning systems, the Germans have achieved great results. A special place was occupied by radio intelligence - by the spring of 1942, after the frequent reports of submariners about sudden nighttime attacks from the air, the detector of radar radiation FuMB1 “Metox” was developed, nicknamed “Biscay cross” for its distinctive appearance. The detection range of the device was twice the range of the British radar - under normal conditions, the boat received a "time bonus" in the form of 5-10 minutes to dive and go unnoticed. Of the minuses - with each ascent, the antenna had to be lifted out of the compartment and manually mounted on the bridge. Increased time of urgent immersion.
However, the use of the "Biscay Cross" allowed for half a year to deprive the effectiveness of the allied anti-submarine forces. As a result, for the 1942 year, the “steel wolves of the oceans” sank 1,5 times more ships and ships of the enemy than in all the previous three years of the war combined!
The British just did not give up and created a new radar, operating at a wavelength of 1,3 – 1,9 meter. In response, FuMB9 Vance station appeared immediately, which allowed the Germans to continue their eerie fishing with high efficiency until the autumn of 1943 (despite the tough measures taken, the Allied losses still exceeded the losses of 1940 or 1941).
By the fall of 1943, the Germans launched the new FuMB10 Borkum anti-radar series, which controlled the 0,8 – 3,3 wave band of the meter. The system has been continuously improved - since April, the new FuMB1944 Fleige detection stations have appeared in the submarine fleet since April.
The appearance of the American centimeter radar AN / APS-3 and AN / APS-4, operating at a wavelength of 3,2 cm, the Germans responded with the creation of FuMB25 “Mücke” (controlled the range 2 – 4 cm). In May 1944 of the year, the most sophisticated radio intelligence intelligence complex FuMB26 "Tunisia" appeared, combining all previous developments on the topics "Muke" and "Flyge".
The only surviving submarine Type VIIC - U-995.
Fantastically beautiful ship
Fantastically beautiful ship
But, despite the solid successes in the field of radio engineering, the primitive diesel-electric boats still spent 90% of the time on the surface, which clearly demanded an increase in their combat stability by equipping the boats with effective means to repel air attacks.
For the reasons already stated (the boat is not an air cruiser), it was impossible to create anything fundamentally new. Increasing the defensive capabilities of U-bots was achieved in two main ways:
1. Creation of new automatic anti-aircraft guns with a higher rate of fire.
2. The increase in the number of "trunks" of anti-aircraft artillery on board a submarine, the expansion of sectors of fire, the improvement of working conditions for calculations.
From December 1942, the new Flak 20 automatic cannons began to appear on the boats instead of the 30 mm anti-aircraft Flak 38, which had a four-fold higher rate of fire - up to 960 shots / min., Also installed in twin (“zilling”) or quad (“fielling”) ) options.
William Rollman's U-848 perishing. The platform with anti-aircraft guns is clearly visible, the crew is hiding from the bombings of the depth charges and heavy fire of the Liberator machine guns.
Along the way, the boats were equipped with powerful 37 mm 3,7 cm Flak M42 anti-aircraft guns - initially an army weapon modified for sea use, firing 0,73 kg shells. Rate of Fire - 50 shots / min. Two or three hits from Flak M42 were enough to dump any enemy aircraft into the water.
On some boats mounted "non-standard" air defense kits, for example, Italian 13,2 mm coaxial machine guns of the company "Breda". On the part of the IX series of submarines, large-caliber 15 mm MG MG 151 machine guns were placed on the sides of the bridge. Also, on the railing of the bridge, several MG34 rifle-caliber machine guns were often mounted.
In order to increase the number of trunks and expand sectors of fire, the designers continuously improved the structure of the cabin and superstructures of the boat. For example, the workhorses of Kriegsmarine - type VII submarines by the end of the war had eight different chops and superstructures (Turm 0 - Turm 7). The “cruising” type IX boats were no less powerfully modernized — they received a set of five superstructures of various shapes and contents.
The main innovation was the new artillery platforms, installed behind the deckhouse, received the nickname Wintergarten (“Winter Garden”) among the sailors. On part of the type VII boats, platforms and beds with the Flak M88 37 mm guns began to be installed instead of the 42 mm guns that had lost their relevance.
As a result, by the end of the war, the standard version of anti-aircraft weapons on type VII boats was the Turm 4:
- Two paired 20 mm Flak 38 guns on the upper deckhouse platform;
- long-range 37 mm Flak M42 anti-aircraft gun in the “Winter Garden” behind the cabin (later replaced with the twin Flak M42U).
Kriegsmarine anti-aircraft boats
As practice has shown, all the measures taken to protect the boats from air attacks were not enough. It was especially hard on crossings in the Bay of Biscay: boats coming out of bases on the coast of France were hit by heavy fire from the British Isles - Sunderland, Catalina, special Mosquito, Whitley and Halifax bombers. ", Heavy patrolmen" Liberators "and" PrivateiTry "," Bofaytery "and fighter aircraft of all types-were being sent on boats from all sides, trying to prevent the Germans from communicating in the Atlantic.
The solution of the problem matured quickly - to create special "anti-aircraft" boats, for escorting combatant submarines on the approach to bases on the coast of France, as well as to cover "milk cows" in the open ocean (Type XIV transport boats intended for supplying fuel, ammunition and food to boats) acting on remote communications - due to their specificity, “cash cows” were a tasty target for the allied anti-submarine forces).
The first Flak-boot (U-Flak 1) was converted from a damaged U-441 boat — two additional artillery platforms were mounted to the bow and stern from the deck, the Flak M20 anti-aircraft gun had two four-barreled 38 mm machine guns. as well as many MG42 machine guns. The bristling boat should have become a terrible trap for enemy aircraft — after all, the British clearly do not expect such a turn of events!
However, the reality was discouraging - 24 May 1943, U-Flak 1 was attacked by the British flying boat Sunderland - the submariners managed to shoot down the plane, but the five depth charges dropped by them caused serious damage to the submarine. A day later, the beaten Flak-boot barely returned to the base. The next combat patrol ended even more tragically - the simultaneous attack of the three Bofighters led to the death of 10 from the crew of U-Flak 1.
The idea of an "anti-aircraft boat" suffered a complete fiasco - by October, the U-Flak 1 had returned its original appearance and designation, re-equipping it into the usual "front-row" Type VIIC. It is noteworthy that in June 1944, the U-441, together with a group of other boats, was urgently sent to the English Channel with the task of preventing the Allies from landing in Normandy (oh, holy naivety!).
7 June 1944, the U-441, managed to knock down the "Wellington" Canadian Air Force, and that was the end of its combat career - the next morning, U-441 was sunk by the British Liberators.
In total, the U-441, U-621, U-951 and U-256 (the same one that shot down the most aircraft) were re-equipped with the “anti-aircraft boat” project. If the ideas were successful, it was planned to re-equip a few more boats (U-211, U-263 and U-271) into the U-Flak, but alas, these plans were never realized.
Despite the vigorous development of anti-aircraft weapons, German boats had to enter into a duel with enemy aircraft less often - the appearance of snorkels (devices for operating a diesel engine underwater, at periscope depth) reduced the surface time to a minimum.
During World War II, boats proved that they were capable of massively exterminating enemy aircraft (along with spare parts, fuel and ammunition), while it lay unassembled in the holds of transport ships. But if the planes have time to “get on the wing” - in such a situation, the boat has nothing to do on the surface. It is urgent to go to a safe depth.
In all, during the Battle of the Atlantic, Allied aviation recorded 348 from 768 German submarines destroyed (45% of Kriegsmarine losses). This figure includes the victories 39 that were achieved by the joint actions of aircraft and anti-submarine ships of the Navy. Also, an insignificant number of boats were blown up by mines exposed by airplanes (no more than 26-32 units, the exact value is unknown).
For the sake of justice, it is worth noting that during the same period of time, German submariners sank 123 combat ships and 2770 transport ships with a total tonnage of 14,5 million tons. Exchange is more than fair! In addition, the boats carried out sabotage and offshore operations in the coastal zone (for example, attacking a Soviet weather station on Novaya Zemlya), conducted reconnaissance, landed sabotage groups, used the Kiel-Tokyo circumnavigation line, and at the end of the war evacuated many fascist bonzes and the gold reserves of the Reich to South America. Those. justified its purpose for all 100 and even 200%.
Instead of an epilogue
The confrontation of the aircraft and the submarine has more acutely exacerbated in our time: since the 1960-s, the massive appearance of rotorcraft allowed the transfer of the lion's share of the tasks of anti-submarine warfare troops to helicopters. Basic aviation is not asleep - the naval forces of foreign countries are replenished annually with new anti-submarine aircraft: the Poseidon P-8, created on the basis of the passenger Boeing 737, replaces the outdated Orion.
Nuclear boats went deep under the water, but the means and methods of detection do not stand in one place. The visual and radar detection of surfaced submarines has been replaced by much more sophisticated techniques:
- magnetic detectors, detecting the presence of a submarine by local anomalies in the magnetic field of the Earth (reception is poorly applicable in high latitudes);
- scanning the water column with a laser of green-blue light, well penetrating to great depths;
- thermal sensors, fixing the slightest changes in water temperature;
- supersensitive devices that record the oscillations of the oil film on the sea surface (which is almost everywhere) with the forced displacement of the volume of water below the sea surface.
I’m not even talking about such “primitive” things as discharged sonar buoys or towed GAS antennas that have long been used on PLO helicopters.
Anti-submarine helicopter MH-60R "X Hawk"
All this allows anti-submarine forces, in the presence of quantitative superiority, good preparation and a certain amount of luck, to discover even the quietest modern boat.
The situation is bad, the submariners have nothing to answer the enemy aircraft. The presence on board of several MANPADS is nothing more than a curiosity - their use is possible only in the surface position.
Probably many generations of submariners wanted to get some weapon, in order to directly “undermine” the insolent helicopter pilots from under the water. The French concern DCNS seems to have found an effective solution - the A3SM Underwater Vehicle anti-aircraft missile system based on the MBDA MICA rocket. The capsule with the rocket is fired through a conventional torpedo tube, further controlled via a fiber optic cable, the rocket is carried towards the target at a distance of up to 20 km.
The target designation is provided by hydroacoustic equipment of the boat - modern gas systems are able to accurately calculate the location of the turbulence on the water surface formed by the helicopter's propeller or the low-flying PLO aircraft engines (the height of the Poseidon patrol is only a few tens of meters).
A similar development is offered by the Germans - the IDAS (Interactive Defense and Attack System for Submarines) complex from Diehl Defense.
It seems that the boats again go into the gap!