Game changers!

[stona]

Shorts 184....thanks for that.

The most cost effective method of attacking shipping from the air hasn't even been mentioned! Mine laying.

Between April 1940 and May 1945 the RAF's mine laying operations accounted for 638 vessels from 19,917 sorties for a loss of 450 aircraft.
366 were sunk by direct attack for an expenditure of 37,837 sorties and a loss of 857 aircraft.
One vessel was sunk for every 31 mine laying sorties or every 104 attack sorties. The BBSU concluded that each vessel sunk by mine cost 0.55 aircraft whereas for the anti shipping squadrons this was 5.28 aircraft per vessel sunk. This latter figure did improve later in the war with the introduction of the Strike Wings whose losses on daytime operations were 1.62 aircraft per vessel sunk, still expensive.

Torpedo attacks were the most expensive, 3,000 man MONTHS per vessel sunk. Second, at 2,600 man HOURS was low level bombing attacks.This compares with 2,300 man HOURS per vessel sunk for the Mosquito Wings using rockets, by far the cheapest method.

To add to the problems of cost and maintenance of torpedoes, the British suffered a severe shortage all the way up to mid 1943.
Coastal Command's own ORS concluded in its report 'Air Attacks on Merchant Vessels' (Dec '42) that bombing attacks were more effective than torpedo attacks, and would be made even more so with the use of the Mk XIV bomb sight.


Cheers

Steve

 

[Shortround6]

Mine laying is very effective in certain circumstances, However fleets/task forces or even groups of ships at "sea" is certainly not one of those circumstances. "Sea" being anywhere the ships really have freedom of maneuver. Mining also works best in "shallow" water. Shallow being several hundred feet or less.

And the term "vessel" is hardly precise as it covers just about anything that floats. 45,000 ton Battleship or 20 ton barge.
Trying to torpedo coastal shipping in daylight using aircraft is going to be expensive in losses for the attackers.
Trying to stop raiders using mines once they are a few dozen miles from port is probably futile.
Each weapon has it's place.

 

[pinehilljoe]

Shorts 184....thanks for that.

The most cost effective method of attacking shipping from the air hasn't even been mentioned! Mine laying.


Cheers

Steve

My earlier point about the B-29 being a game changer. During Operation Starvation, during the last 6 months of the war, ONE B-29 group of 160 planes was assigned to lay mines in the Japanese inter-coastal sea lanes. The mines sank or damaged 670 ships totaling more than 1,250,000 tons for the loss of only fifteen B-29s. More than all other methods of attacking shipping over the same period.

 

[stona]

The British, or at least the RAF (Bomber/Coastal Commands) with a few notable exceptions hardly concerned themselves with the German surface fleet. The two priorities were anti submarine and anti trade operations. The primary target of the latter was the flow of raw materials from Norway.

Action and adventure on the high seas are great for propaganda and ideal subjects for post war films, but wars are won on more mundane events.

It cost coastal command 2,500 man months to sink a ship. The total cost to the German economy of the loss of an 'average' vessel of 3,000 tons was 8,600 man months. This is how wars are won.

Between 14% and 17% of Germany's merchant fleet was more or less continually in need of repair. Between July 1943 and the end of the war there was a 79% reduction in the production of steel plate suitable for the building and/or repair of smaller merchant vessels. About half the plate allocated to the 66 vessels (300,000 tons) in the Hansa Emergency Shipbuilding Programme 1944/45 could have been used for U-Boat production. It was not because repairing or replacing merchantmen was more important to keep the economy moving, and this did effect the production of U-Boats by indirect means.

Cheers

Steve

 

[nuuumannn]

I cannot deduce what aircraft were used in the Dardanelles, but given that the first flight with a torpedo slung from an aircraft was achieved on 28th July 1914 by an aircraft (unnamed in source) designed and built by Short Bros. that would be my best guess.

Two different aeroplanes, actually. The aircraft used on 28 July (oops I said June in an earlier post) was a Short Folder Seaplane, which differed in powerplant to the 184, being powered by a 160 hp Gnome rotary, while the 184, which was bigger was powered by a 225 hp Sunbeam Mohawk. The 184 was also known as the Short 225 as a result of its engine power output. Short 166s were also used during the Dardanelles campaign, which were essentially similar to the Folder, but not for torpedo duties. These were restricted to the Ben-My-Chree's three Short 184s. Rather prescient that the navy should send a seaplane tender to the war zone with the specific role of torpedoing enemy shipping.

Both these pics were taken during the Dardanelles campaign:

This is a Short 166, which was operated by the seaplane tender Ark Royal and is pictured at the makeshift seaplane station at Kephalo Bay on the island of Imbtros. Note the torpedo crutch between the floats, although the 166 was actually insufficiently powerful to carry one aloft. Even the 184s struggled to get airborne with a torpedo and were flown as single-seaters to save weight on torpedo ops.

This is Short No.184, which was George Dacre's aircraft, who sank a Turkish vessel from the surface of the water after it suffered engine failure forcing Dacre to alight on the surface. After fixing his engine from the floats, he started it and taxied into a firing position and launched his torpedo, at which point he was noticed by Turkish spotters on the shore, who began to fire at him. Gunning his engine, he bounced along the water's surface for about a mile whilst under fire, eventually getting airbore, before his engine failed again! he was able to glide back to the Ben-My-Chree.

The Squadron Commander. (C. Estrange Malone) on board Ben-my Chree wrote.

"One cannot help looking on this operation as being the forerunner of a line of development which will tend to revolutionise warfare.

I used this very same quote in a series of articles on air operations in the Dardanelles published last year for the centenary of the campaign. (Psst - it's Cecil L'Estrange Malone)

 

[stona]

Cecil L'Estrange Malone)

I don't think even the toffs give their children names like that anymore, or maybe they just aren't the kind of people I'm likely to meet

I did once meet the superbly named Evelyn Bufton-Morriss, a Captain in the Glosters, when I was involved in the celebration of that great Regiment's tercentenary back in '94, before they got 'amalgamated'.

Cheers

Steve

 

[nuuumannn]

I've always liked the name Cecil!

 

[Shortround6]

The British, or at least the RAF (Bomber/Coastal Commands) with a few notable exceptions hardly concerned themselves with the German surface fleet. The two priorities were anti submarine and anti trade operations. The primary target of the latter was the flow of raw materials from Norway.

Action and adventure on the high seas are great for propaganda and ideal subjects for post war films, but wars are won on more mundane events.

It cost coastal command 2,500 man months to sink a ship. The total cost to the German economy of the loss of an 'average' vessel of 3,000 tons was 8,600 man months. This is how wars are won.

Between 14% and 17% of Germany's merchant fleet was more or less continually in need of repair. Between July 1943 and the end of the war there was a 79% reduction in the production of steel plate suitable for the building and/or repair of smaller merchant vessels. About half the plate allocated to the 66 vessels (300,000 tons) in the Hansa Emergency Shipbuilding Programme 1944/45 could have been used for U-Boat production. It was not because repairing or replacing merchantmen was more important to keep the economy moving, and this did effect the production of U-Boats by indirect means.

Cheers

Steve

All that is true but the British certainly tried to use mines as a general blockade. It was pretty much a failure. 170,000 mines were laid by surface craft in defensive mine fields, the majority in the Iceland to Faroes barrier that sank one known German submarine. This field was laid from July1940 to early 1942 with a few supplemental layings later on. What is interesting, in a negative way, it that anybody studying the 1918 Orkney to Norway barrier mine field could have pretty much predicted the results or lack thereof.
Granted these were not air launched (or more more properly air delivered) but do show that no one weapon was the answer to multiple tactical situations.

One reason the mine fields were effective in coastal waters was the coastal shipping patterns/lanes/routes were constrained by the threat of attack from aircraft or surface ships. That is going further from shore might reduce the threat of mines but increased the time exposed to air or surface attack (or submarine of the coast of Norway). Some movements being by night or bad weather only.
That and some of the air attacks on "vessels" may have been on minesweepers. Germany had or built over 620 minesweepers during the war not included captured vessels or converted merchantmen.
Un-protected mine fields are usually swept fairly soon. Protected mine fields are those that have some sort of deterrence/hindrance to sweeping. Coastal batteries, gun boats/floating batteries, air patrols, Naval patrols., etc.
True cost of effective mine campaign includes a lot of auxiliaries.

 

[stona]

It was Coastal Command that forced the Germans to route their convoys close to land and to sail only at night. Many Norwegian sailed through the Inner Leads making them difficult subjects for air attack. These convoys were entirely dependent on navigational beacons and lighthouses and these were attacked by the British, following an agreement with the Norwegian government. Other efforts to force shipping out of the Inner Leads involved one of the great bluffs of the campaign.
Most of the channels were too deep for anchored mines, the Admiralty did not have any moored mines capable of being dropped by aircraft anyway. The British reasoned that the Germans would not be aware that air dropped moored mines were not available. Moored mine laying was simulated by dropping single large bombs from low level into the deep water channels. The bombs had delayed action fuses set to simulate premature mine detonations. The ruse only partially worked, the Germans did continue to use the routes but several convoys were delayed whilst the channels were swept of non existent mines!
Cheers
Steve

 

[gjs238]

I've always liked the name Cecil!

It's a unisex name

 

[gjs238]

It was Coastal Command that forced the Germans to route their convoys close to land and to sail only at night. Many Norwegian sailed through the Inner Leads making them difficult subjects for air attack. These convoys were entirely dependent on navigational beacons and lighthouses and these were attacked by the British, following an agreement with the Norwegian government. Other efforts to force shipping out of the Inner Leads involved one of the great bluffs of the campaign.
Most of the channels were too deep for anchored mines, the Admiralty did not have any moored mines capable of being dropped by aircraft anyway. The British reasoned that the Germans would not be aware that air dropped moored mines were not available. Moored mine laying was simulated by dropping single large bombs from low level into the deep water channels. The bombs had delayed action fuses set to simulate premature mine detonations. The ruse only partially worked, the Germans did continue to use the routes but several convoys were delayed whilst the channels were swept of non existent mines!
Cheers
Steve

Interesting! Any more info on the bold part above?

 

[parsifal]

British mines were used both offensively and defensively and were intended initially as a deterrant to both surface warships and uboats. As time progressed, on the northern front, the greatest successes by the Allied mining effort in home waters and across the Denmark Straits were against enemy controlled shipping. something in excess of 300000 mines were laid in and around home waters and in the Baltic. I don't have the figures handy, but the results of this massive effort were very modest.

in the med, the allied efforts at mining were far more limited, but the results were also a bit better in my view. Of the 4.3 million tons of axis shipping lost in the MTO to September 1943, 174,000 tons of shipping was lost to mines, but of this total 98000 tons were lost from June 1940 to September 1941, and overwhelmingly, these losses were due to the offensive efforts of the malta based 830 squadron who pioneered for the FAA the air launched mine, from those non-game changing swordfish (representing 4.1% of total axis shipping losses in the med) . Until june 1940 the numbers or tons of mines dropped by FAA aircraft could be counted on one hand and results were correspondingly non-existent. don't know the tonnages of mines laid by the RAF in that period, but axis shipping losses to british air dropped mines were again almost non-existent. whilst a somewhat dangerous over simplification, the RN relied almost exclusively on ship launched mines until the latter part of 1940, and these almost exclusively were defensive in nature.

The malta based FAA squadrons, along with the malta based submarines launched a mere fraction of the mine numbers compared to the masses released by the allies in the nth sea and other home waters. Defensively the home waters mines were successful (in that they materially affected DKM estimates for success in Seelowe) but as offensive weapons the med based groups were all over it.

Axis efforts by comparison were also a mix of surface launched defensive mines and air (and u-boat launched offensive mines). The germans made one notable slip up during the war in the mine wars. at the outbreak of the invasion of Norway, the Kattegat was not mined and british submarines were able to unleash a devastating attack on German shipping, sinking close to 500000 tons of shipping in a month. That was about 25% of total german shipping at the time and a devastating blow to their transport capabilities. They quickly rectified that problem, and the leads of Norway, a belt of shoals and reefs just offshore the jagged Norwegian coast was a natural barrier, easily sealed at the few entry points that protected axis shipping very effectively until 1943

The axis offensive capabilities were devastating for the efforts they put into it. The early offensive with magnetic mines in 1939-40 is well known. less well known are the efforts of the LW during the Dunkirk evacuation, often deliberately obscured because most of the losses were on ships under 500 tons and these little ships are often not included in tonnage losses for shipping ( including the numbers quoted below) June 1940 remained the worst month for the war if those little ships are included, with close to a million tons lost, most of them to air dropped mines and something like 300000 tons of small craft lost (and not recorded).

The following is a bit of a breakdown of Alied shipping losses, the first number being the losses to mines, the second number being overall admitted losses:

1939: 262500/755232......35% of the total losses
1940: 509889/3991641....12.7% of the total losses
1941: 230842/4328558.....5.31% of the total losses
1942: 104488/7790697....1.34% of the total losses
1943; 108638/ 3220137....3.37% of the total losses
1944: 95855/1045629......9.16% of the total losses
1945: 93663/438821.......21.33% of the total losses

 

[stona]

Interesting! Any more info on the bold part above?

The attacks on the lighthouses, eventually 15 were 'put out of action', came in early 1945 and against a background of some tension between the British and Norwegian governments. Norway was occupied but she was also an ally, one of the reasons so many convoys were attacked and located was because they could rarely sail without the Norwegian resistance informing London, they were also tracked by the Norwegians when the passed through the Leads and in the Fjords.
On 24th August 1944 the Royal Norwegian High Command issued a warning via the BBC that heavy attacks on shipping along the Norwegian coast were expected and asking that Norwegian civilians keep to a minimum fishing and other seaborne activities.
Shortly afterwards Coastal Command crews were reminded that passenger or fishing vessels marked with Norwegian flags were not to be attacked.
On 21st September Mosquitoes of Nos. 235 and 248 Squadrons mis-identified and sank a Norwegian fishing vessel of 75 tons.
On the night of 15/16 October a Norwegian fishing vessel of 150 tons was bombed by a Halifax in the Skaggerat.
The Norwegians were obviously not happy about these incidents, but understood that mistakes can be made. Then on 8th January 1945 Beaufighters of the Dallachy Wing attacked a Norwegian passenger vessel and a fishing boat on one operation, sinking both. This was a step too far and the Norwegian Government in Exile raised objections in London, finally accepting that the aircrews involved believed they were attacking much larger vessels.
On 21st February another incident involving a Norwegian passenger ship occurred, this time the Norwegians had had enough. They demanded a full enquiry and this took place at Banff on 2nd March. The enquiry concluded that the aircraft had an 'extremely short time' to identify the vessel and that its size (490 tons) meant that it could have mounted anti aircraft weapons of sufficient calibre to inflict fatal damage on the aircraft. Bad weather was ultimately blamed for the failure to correctly identify the vessel. The conclusion was accepted by the Norwegian government.
Unfortunately, on 23rd March Beaufighters seriously damaged a coastal passenger steamer and a fishing boat, killing five Norwegians. Poor visibility was once again blamed for the failure to identify the targets. This time Group Captain R T Corry, Commanding Officer Dallachy Station, made a formal apology to the Norwegians via No. 18 Group headquarters. The headquarters reissued the instruction of 12th October 1944 which specified in detail the restrictions on the attack of small vessels off the Norwegian coast. At each briefing before anti-shipping operations crews were to be reminded of the regulations and the rules of engagement clarified such that if there was any doubt about the size or identification of a vessel, an attack was not to be carried out.
The attacks on the lighthouses did not commence until 9th March 1945, having been delayed for several weeks by the negotiations with the Norwegian Government in Exile, which were obviously complicated by these incidents. Britain and Norway had a common goal in the defeat of Germany, but the Norwegian government also had a responsibility to its citizens. The British never stopped their attacks, but it would be unfair to suggest that they rode rough shod over Norwegian concerns. They did listen to the Norwegian government and they did make efforts to mitigate and minimise the inevitable Norwegian losses in such a campaign.
Most British people then, and now, would consider the Norwegian people to be friends, we have a long shared history across the North Sea, and no one wants to kill their friends, even by accident and when larger issues are taking precedence.

......and thanks for the Xmas trees

Cheers

Steve

 

[gjs238]

Targeting lighthouses is interesting.
Wonder if this occurred in all theaters/theatres.

The Japanese "attacked" the Estevan Point lighthouse on Vancouver Island in British Columbia

Bombardment of Estevan Point Lighthouse
More than 5 Japanese submarines operated in Western Canada during 1941 and 1942. On June 20, 1942, the Japanese submarine I-26, under the command of Yokota Minoru,[26] fired 25–30 rounds of 5.5" shells at the Estevan Point lighthouse on Vancouver Island in British Columbia, but failed to hit its target.[27] Though no casualties were reported, the subsequent decision to turn off the lights of outer stations was disastrous for shipping activity.[28]

 

[stona]

Targeting lighthouses is interesting.
Wonder if this occurred in all theaters/theatres.

The Coastal Command attacks were for a specific purpose. The light houses and beacons were the only means by which the convoys could navigate the Inner Leads along the Norwegian coast. They were effectively weaving in and out of the islands and fjords along the coast line, and this made them much harder targets for air attack. By denying the convoys the means to navigate this route (the dummy mining of the Leads was to the same end) the British hoped to force the convoys out to sea where they would present an easier target.
Cheers
Steve

 

[gjs238]

RE: Lighthouses
Just found this at World War II | Sumburgh Head
The rules of war stated that lighthouses were not legitimate military targets.

 

[Shortround6]

Yep, blowing up a light house so that the enemy shipping hits the rocks and sinks isn't fair.
But putting mines in the channel between the rocks and blowing the ship/s up is.

 

[gjs238]

Yep, blowing up a light house so that the enemy shipping hits the rocks and sinks isn't fair.
But putting mines in the channel between the rocks and blowing the ship/s up is.

Yes, kinda like you can't shoot a soldier with an expanding bullet*, but it's fine to burn him alive with a flamethrower.

*The Hague Convention of 1899, Declaration III prohibits the use of expanding bullets in international warfare.

 

[stona]

Yep, blowing up a light house so that the enemy shipping hits the rocks and sinks isn't fair.
But putting mines in the channel between the rocks and blowing the ship/s up is.

You can't stop people mining, and neutral shipping has to take its chance, but you can at least try to prevent combatants attacking lighthouses and other navigational beacons which also serve neutral or non combatant shipping.
I expect that the negotiations with the Norwegian government may have had something to do with the protected status of the lighthouses.
Cheers
Steve

 

[parsifal]

The two sides had differing standards that tended to change as the war progressed. The hague convention required belligerents to declare areas that were not safe due to minelaying activities. these were termed "declared areas". There was no requirement to inform an enemy, but protagonists were supposed to inform neutrals of their activities, and where it was safe for their shipping. Similar to unrestricted uboat war these rules heavily favoured the dominant seapowers and the smaller navies like the KM were soon forced to abandon such announcements and gentlemanly behaviours. unconstrained minelaying carried with it a heavy political and economic cost for Germany. As 1939 and 1940 passed, the germans began to lay mines anywhere, often using untethered drift mines and laying mines in the territorial waters of the neutrals. there were several incidents in 1939-40 with the Scandinavian countries for example (it didn't help that the germans in 1939 were running around, basically seizing any foreign ship in their ports as their own, even those of friendly nations and those trying to trade with the germans. Finland for example, had many ships seized and taken over in German ports at the outset of the war) . Almost in protest, nearly all the free shipping came under the control of the allies 9nearly 6million tons ended up in the service of the allies in this way). most of the Swedish merchant fleet, for example, ended working for the british. Even the Spanish merchant service transported more cargo for Britain than it did for the axis.

The allies were never really able to engage in "unrestricted" minelaying the same as Germany did. They absolutely needed shipping to move as freely as they could and protect it, not lay traps that might sink it. more damage was done in this regard than was done by mines, in terms of putting the germans outside in the cold as a pariah, but there is something about laying mines without telling third parties that really upsets people.

In the pacific, everything was reversed. For the americans, after the loss of so much territory in the far east, these waters were no longer important as a free trade area, whereas for the Japanese they really did not want to make things difficult for their shipping. so the Americans went to town with their minelaying. It was an interesting twist, a dominant seapower applyiny Jeune Ecole strategies with superior resources. almost from the start the Japanese merchant shipping service began to suffer, whereas US shipping losses in the pacific were almost non- existent.