As we’ve seen with the catastrophic rollout of Obamacare; when you’re working on a big project, design and architectural decisions made early in the process can have unintended, and maybe massive, impacts later in the process.
Seventy years ago tonight – the night after Christmas – at the Battle of the North Cape, one of those chains of design-cause to real-world effect came to a dismal conclusion in the frozen, stormy North Atlantic.
When designing military vehicles – whether a Hummvee, an aircraft carrier, a tank or a fighter plane – designers have to balance four, largely mutually-exclusive factors. The design of any military vehicle is a result of the inevitable compromise made between those factors, at any given level of technology.
Those factors are usually summed up as “Firepower, Armor, Speed and Payload”, but are better described as:
- Firepower – how much hitting power the vehicle has. This can refer to the size of a vehicle’s weapons – but also to the amount of ammunition, or the variety of threats it can attack, or the fire control system that helps it hit its target.
- Survivability – which is beyond mere “armor”. For example – US Navy aircraft carriers of World War 2 had little actual metal armor, but they invested immensely in damage control and catastrophe-proofing the ship designs – which led to some of them surviving damage that would have sunk any other nation’s designs.
- Mobility – This can indeed be raw speed. But it can also mean the ability to keep moving in conditions that would stymie other vehicles of its type. That’s a major factor in today’s story, as it happens.
- (A fourth – Payload – sometimes crops up, usually if you’re building a vehicle whose job it is to carry people, supplies or other vehicles – anything from an armored personnel carrier to an aircraft carrier)
Your job is to design a new tank. You have a weight and size limit – your tank has to fit evenly onto a flatbed rail car, so it can be moved around the country. In your design you’re going to cram a huge, powerful cannon into it, along with thick, heavy armor. But that means you’re going to have to put a big engine into it, so that it can actually move. Within the size restrictions you have, that means building a taller, more capacious vehicle to hold the engine – but tall tanks are easier to see at hit, which affects survivability. Making it smaller requires either accepting a slower tank (compromising Mobility), or a smaller gun, or less ammunition for a larger gun (less Firepower), or making it lighter (reducing armor, and thus reducing Survivability).
Naval ships have the same set of compromises.
Global: In the early 20th century, it could be fairly said the sun never set on the British Empire. The Empire and Commonwealth – the network for former colonies that had become independent, but remained part of a close-knit economic and defense alliance – stretched from (using current names except as noted for all the below) Canada, the Bahamas, the Falklands and Belize in the west, east to the Home islands, to colonies, to its Mediterranean holdings (Gibraltar, Malta, and of course the vital Suez Canal, in an Egypt that Britain ruled as a puppet proxy), to the protectorates and Commonwealth states that dominated Africa (Nigeria, Kenya, Tanzania, Uganda, and the commonwealth nations of Rhodesia (now Zimbabwe) and South Africa) and the Middle East (Palestine, Jordan, Iraq, and Britain’s then and present ally and client Oman), its keystone possession India (which then also included what became Pakistan and Bangladesh) and Sri Lanka, and to its’ far eastern colonies in Malaysia, Singapore, Hong Kong, Fiji, and of course its Commonwealth allies Australia and New Zealand.
And from the 1600s on, the Royal Navy was designed to sail, and fight, anywhere in that massive slice of the world – from the stormy, sub-arctic expanses of the far North Sea and North Atlantic, to the temperate reaches of the Mediterranean, to the dolorous tropics of the Indian Ocean.
And over the years, the Royal Navy arrived at a design formula that institutionalized the order of importance of the four key design factors, based on the mission “fight anywhere in the Empire”.
Mobility came first – in terms of “Seaworthiness”, as opposed to “Speed”. A British ship had to be able to weather sea conditions ranging from North Atlantic gales to Indian Ocean cyclones. This meant building ships that were designed and engineered to remain not merely afloat, but controllable in terrible seas. (Mobility expressed as “range” was less important – Britain’s empire had refueling bases about every 2,000 miles, from Halifax Nova Scotia to the UK to Gibraltar to Suez to Mumbai to Sri Lanka to Singapore to Hong Kong. British designers assumed those bases would be available. World War 2 showed it a bad assumption – but we’re jumping ahead, here).
Protection – armor, damage control and catastophe-proofing – as a general rule, came in second. Firepower came in third; too many, too heavy guns and torpedoes made the ships top-heavy, which made them less stable and harder to handle (and more importantly, handle in a combat-effective way) in heavy seas.
Different nations made the compromise differently. The Italian navy emphasized speed over range – they fought in the Mediterranean exclusively, and their main goal was to react quickly to contingencies in that ocean. Its rather placid weather meant “seaworthiness” was less vital. The US Navy, whose main theater of operations was the Pacific, emphasized long range over pure seaworthiness; their firepower was on paper more modest, although greatly augmented by superior technology like fire control radar.
And the German Navy? It was designed to operate in the stormy but confined North and Baltic Seas. Its mission was not to project power around the globe; it was to sink the British Fleet. Range was more or less irrelevant – most missions were measured in days, not weeks (for surface ships – the submarines, or “U-Boats”, were another matter). The crux of the design battle was between raw, pure firepower – cannon and torpedoes – and mobility expressed in terms of speed.
With that in mind, the Germans in 1939 commissioned their second most-famous warship (after the Bismarck, of “Sink the Bismarck” fame), the KMS Scharnhorst.
Scharnhorst and her sister Gneisenau weren’t really “battleships”; they were “Battle Cruisers”; more speed and less armor (but not much less) than battleships, faster and more heavily armed than cruisers (but not quite as powerful as a battleship), the idea was to be able to kill anything that could catch it, and outrun anything that could kill it. But it was built to the German design standard; Speed and Firepower trumped raw seaworthiness (although at 32,000 tons, it was still plenty seaworthy).
Floating Tin Cans: In large ships, like battleships and aircraft carriers, of course, there’s plenty of room to make those compromises.
In smaller ships, it was a much tighter set of compromises.
Destroyers – at least up through the 1960s – were smaller warships designed to escort fleets of larger warships, and to attack much larger warships using (until the missile age) torpedoes. They have to be fast, to not only keep up with the battleships and aircraft carriers they escorted, but to keep their station in formation with the larger ships as they zigged and zagged in evasive maneuvers. So a Destroyer would generally be from 1,000 to 2,200 tons (battleships were 26,000 to 80,000 tons, and aircraft carriers were generally from 12,000 to 30,000 tons in World War 2)
To make things more complicated, the various arms control treaties of the 1920s and 1930s – especially the London Naval Treaty, which sought to curb the naval arms race of the era – placed a statutory limit on the size of warships, and the number of tons of warships that could be built in each class. The limit for most destroyers was 1,500 tons.
So the design challenge for Destroyer builders in the 1930s was, within the treaty tonnage limits, to build an warship that was effective in furthering the nation’s strategic doctrine.
For the British, then, Destroyers were designed within a 1,500 ton limit to be:
- Extremely seaworthy, but with relatively short range and modest speed (35 knots, or about 40mph)
- Modest armament; 4-5 4.7 inch cannon and 6-8 torpedoes. More, heavier guns and torpedoes added topweight, which affected stability which was a key factor in seaworthiness, which was the top priority.
- Extremely minimal protection; destroyers had no armor. They had some damage-proofing in design and damage-control.
HMS Hunter. Built in 1936, it was fundamentally similar to nearly every British destroyer build from 1918 to 1943; four 4.7 inch guns, eight torpedoes, 35 knot speed, and very seaworthy. Hunter was sunk at Narvik in 1940.
The Germans, given their mission that was short on range but long on “sinking British ships”, had a different set of compromises. They enabled these compromises, in part, by ignoring the London Treaty’s limits, and building destroyers that were nearly 1,000 tons heavier than the British ships. Within that limit, the Germans focused on:
- Firepower – in terms of sheer, raw hitting power – was most important. German destroyers carried mostly five 5-inch guns, and many carried five 6-inch guns, usually found on larger 10,000 light cruisers. They fired 100 pound shells, to the 40 pound shells fired from the Brits’ 4.7s.
- Mobility – in terms of raw speed – was next. German destroyers clocked from 36-38 knots. Range was less important – German destroyers rarely expected to be at sea longer than a week, operating from bases like Kiel, Wilhelmshaven, and – after 1940 – occupied Norway, Denmark and France. Seaworthiness came in well down the list; the heavy gun and torpedo batteries, and the design compromises to enable the high speed, made the ships much less stable than British ships; in bad weather, they’d float, all right – but they’d be rocking back and forth too hard to fire their guns effectively.
- Protection, as with all destroyers, was a matter of “not being hit”. Especially for the Germans – structural strength came in lower on the list of priorities.
The German Z36, short for “Zerstörer 36″, or “Destroyer number 36″. German destroyers were numbered, not named.
Among the nation’s destroyers, a “Tortoise and Hare” comparison works; British destroyers were slower and more lightly armed, but seaworthy enough to not merely survive, but fight, in much worse weather. The Germans had the edge on speed and firepower.
(The US Navy, by the way, split the difference, more or less. Our destroyers, until the eve of war, were designed to operate in the vast ranges of the Pacific; an American destroyer could steam three times as far as its Brit counterpart. They also had only four or five guns – five-inchers firing 60 pound shells. But those five inch guns were able to shoot at both surface ships and aircraft; this made them a bit heavier than single-purpose anti-ship guns, a technology edge that gave US destroyers an immense advantage in anti-aircraft firepower over those of any other nation on earth at the time, a difference that was absolutely crucial as air power supplanted surface to surface action as the main form of war at sea. And to pay for the weight that went into fuel and dual-purpose guns, the US destroyers sacrificed some seaworthiness (three sank in a typhoon in 1944) and a little speed and, on the eve of the war, the treaty limits themselves, dumping the 1,500 ton limit and building destroyers of 2,200 and later 3,000 tons).
USS Fletcher. Built after the US belatedly abrogated the London Treaty, the Fletchers were 2,200 tons, and armed almost identically to the earlier 1,500 ton ships. This made them rugged, seaworthy, powerful-enough, with plenty of fuel to tackle the vast Pacific – and able to be updated continuously. Fletcher-class destroyers served into the 1970s in the US Navy, and the last one, the Mexican Cuitlahuac ( formerly USS John Rodgers), remained on active service until 2001 – a phenomenal record for a ship class.
Duel In The Sleet: In December of 1943, the German high command realized that the war was going badly. Especially on the Eastern Front, where the debacle at Stalingrad had been followed by a series of gruesome setbacks.
Part of the problem for the Germans was that the Soviet military’s main weakness – its inability to support lengthy operations due to the difficulties in providing supplies to the front and communications among units – was being rapidly fixed by an onslaught of American equipment, especially trucks and radios – in addition to weapons to augment the Soviets’ own production, especially fighter aircraft.
A Bell P-39 Airacobra in Soviet service. A failure in US and RAF service, it was a hit with the Soviets; it was vastly more reliable than mid-war Soviet planes, and it amply suited the tactical situation on the Russian front. Counting raw numbers of kills in Soviet service, the P39 may have been the most successful US fighter design of World War 2.
And these supplies were delivered to the USSR via convoys of merchant ships that crossed the North Atlantic, skirted the north cape of occupied Norway, and docked at the Soviet ports of Archangelsk and Murmansk. These convoy routes served as among the most dangerous and bloodiest – and most unsung – battlefields of the war; attacked by U-boats and aircraft from occupied Norway, and occasionally heavier German surface ships, they were an incredibly risky, but vitally important, sideshow.
And Germany needed the routes blocked. With that in mind, in December of 1943, German admiral Karl Dönitz ordered Scharnnorst and a flotilla of five destroyers to sortie from Altafjord to attack a convoy of twenty merchants plus escorts that were headed for the North Cape.
On the afternoon of December 22, German Rear Admiral Erich Bey sailed Scharnhorst and the destroyers to sea. At the depths of the arctic winter, the “day” involved 45 minutes of daylight, six hours of twilight – and 17:15 of darkness. This was an advantage to the British; over the course of the war, they and the US had developed radar fire control that allowed their ships to not only find the enemy, but to control their gunfire and shoot almost as effectively at surface ships (as opposed to aircraft) in the dark as in daylight. The Germans were lagging badly at this in 1943 (and throughout the war).
Even worse – and unbeknownst to the Germans – the Allies were reading German radio communications in almost real time. As noted earlier in this series, British, Polish and French researchers had thoroughly broken the German “Enigma” code. The good news for the British? They knew the exact route the Germans would take to intercept the convoy. The bad news? They didn’t have a lot of time. The convoy – screened by three British cruisers under Admiral Robert Burnett, would have to fend for themselves for a few hours, while a powerful force under Admiral Bruce Fraser, with the battleship HMS Duke of York and the cruiser Jamaica, and four destroyers (one manned by a Norwegian crew) raced to the scene.
At about 8AM on Christmas Day – still in the dark, and in wretched weather – Scharnhorst was spotted by the British cruiser HMS Belfast, who along with Norfolk and Sheffield had interposed themselves between the convoy and the Germans.
HMS Belfast today. It’s a museum ship in the Thames, just upstream from London Bridge. The only surviving WW2 British cruiser, and the only vessel from the Battle of the North Cape never sunk or scrapped, it’s an amazing visit if you’re a ship geek like me. Yep, I’ve been there.
Aided by radar, Belfast fired first. A lucky hit destroyed the Scharnhorst’s main radar antenna, leaving the ship partially blind (the backup radar didn’t cover the ship’s forward arc; imagine driving with a blocked windshield, and having to weave back and forth to see forward out your side windows).
Scharnhorst‘s mission was to sink merchantmen, not slug it out with cruisers. Bey disengaged and spent the rest of the day looking for a way to outflank Burnett’s cruisers.
And it was here that the design decisions, made in the 1920s and 1930s and so laboriously explained above, come roaring into the picture.
The weather, bad to begin with, worsened. A howling gale whipped up mountainous seas. Snow obscured the already terrible vision. Imagine some of the worst weather from Deadliest Catch. Now, imagine trying to load a cannon, or stabilize a range-finder, or even see a target, in that kind of weather.
The German ships, designed for raw speed in calmer waters, were badly-fitted for seakeeping in terrible weather. The five German destroyers especially suffered; the top-weight of the heavy guns made them roll terribly, to the point where even if they’d seen a target, they’d have had a hard time loading and firing their cannon at all, much less with accuracy. And the ships’ structures – structurally lighter to save weight and increase speed – weren’t up to the pounding; the destroyers started taking structural damage from the pounding of the icy waves. Scharnhorst , being much bigger, was structurally sound – but was also built for higher speed in calmer seas; it was forced to slow down, to slow the rolling and to allow the destroyers to keep up. Finally, hearing reports of serious damage, Bey ordered the destroyers back to base, and sought to engage the convoy himself.
The British ships, on the other hand, were able to not only to continue to sail, and sail toward the enemy, but to fight when they got there. As they – Fraser’s Duke of York task force – closed in, Bey engaged Burnett again, hitting HMS Norfolk twice with his 11-inch guns, knocking out the British cruiser’s gunnery radar. But the three cruisers were a formidable opponent to the German; and Bey withdrew, still hoping to find the convoy. Belfast kept Scharnhorst under radar surveillance.
And this allowed Fraser to engage Scharnhorst with gunfire from the Duke of York at 4:17 PM – again, in pitch dark. Fraser’s guns – the 40,000 ton Duke‘s ten 14-inch guns to Bey’s nine 11-inchers – made it a lopsided battle; the superiority in radar made it even worse, allowing the Brits to lock in Bey’s position long before Scharnhorst’s gunners even got close. And while the German ship had been designed to be able to outrun any ship that could kill it – Scharnhorst could do 32 knots, Duke of York 28 in ideal conditions – in the atrocious seas the British battleship was able to out-steam the German. And without destroyer escort to hold off the larger British ship to allow Scharnhorst to escape, it was a massacre.
The British battleship pounded the German, knocking out six of the nine main guns and wrecking half of the boilers; two destroyers (HMS Scorpion and the Norwegian-manned HNoMS Stord), fully combat-effective in the weather due to their seaworthiness, hit the German ship with four torpedoes, stopping it.
His Norwegian Majesty’s Ship, the destroyer Stord. An “S-class” destroyer built as HMS Success in 1942, then handed over to the Norwegians and renamed. It looks a little more rakish than Hunter (way above), but it’s built to almost the same basic design; four guns, eight torpedo tubes, as the ten-years-older Hunter, and it had similar capabilities (although much better equipped with radar and anti-aircraft guns). It served the Norwegian navy until 1959.
After that, it was a formality; Belfast and sister cruiser HMS Jamaica closed in and finished Scharnhorst off. The Brits rescued 36 out of a crew of over 1,900.
It was one of many examples in the war of systems that were on paper looked much better than the opposition came up short when exposed to real-world conditions that weren’t accounted for on paper.