Even as Roma and the invasion fleet off Salerno were attacked by the German guided bombs, the Allies began to desperately search for countermeasures. They had first learned of the project from the Oslo Report, sent in November 1939 by anti-Nazi physicist Hans Mayer, who passed the British a document containing information on a number of secret German military projects, including German radars, radio-navigation equipment, and the first hints of what ultimately became the V-2 rocket. The British, viewing the report as too good to be true, disregarded the contents.

An Hs 293

The next warnings came in mid-1943, courtesy of ULTRA, and were taken rather more seriously. Even better, some of the crew from the aircraft shot down over Salerno were captured, giving the Allies some insight into the operation of the system. Recording equipment intended to capture the control signals so countermeasures could be developed was fitted to a few escorts. Unfortunately, the Allies concluded that the Kehl-Strasbourg system worked on frequencies between 10 and 35 MHz, leaving the actual frequency of 48-50 MHz clear. Thus, the first jammers, developed by Howard Lorenzen at the Naval Research Laboratory were completely ineffective.¹ However, Lorenzen's team also set to work creating a set of improved receivers to pick up the Kehl-Strasbourg signal. The whole package was installed on the new destroyer escorts Herbert C. Jones and Fredrick C. Davis, which were promptly dispatched to the Mediterranean. Read more...

I've discussed many facets of commercial aviation, ranging from how airlines set prices to their route networks to safety. But one of the more interesting aspects is the ways in which airlines work together, and why. These range from helping each other's passengers when things go wrong to combining their networks to provide service around the world.

The replica Dingyuan

The biggest issue is that no one airline can fly everywhere. Let's say I want to go to Weihai, China, to see the full-size replica they constructed of the ironclad Dingyuan, one of the ships that fought at Yalu River during the Sino-Japanese War. Obviously, nobody flies direct from Oklahoma City to Weihai, and because it's a fairly minor Chinese city, no American airline even flies there, nor does any international airline fly to OKC. So at some point, I'm going to have to change airlines. This might mean booking multiple tickets, having to schlep my luggage between the baggage claim and the check-in counter, and being in trouble if something goes wrong and I miss a flight. Read more...

The American campaign against Japan was fought in the vast reaches of the Pacific, and enabled largely by the efforts of auxiliary ships. The ability to refuel at sea gave the USN great reach, and a wide variety of ships were developed to allow deserted islands to become forward bases for the fleet. In the closing months of the war, improved techniques for underway replenishment allowed ships to stay in forward areas much longer, greatly reduced reliance on these bases and the need for their ships. But while many of the auxiliary types that were in service then have died out, others have been developed to take their place, and play vital roles on the oceans of the world today.

Salvage ship USNS² Salvor

Some types have survived more or less unchanged. The USN still has a pair of submarine tenders based in Guam to provide support to the undersea vessels of the 5th and 7th Fleets. Two hospital ships, Mercy and Comfort, were converted from oil tankers in the 80s and today serve primarily to project soft power by bringing medical aid to those in need. Each has a 1,000 bed hospital, 12 operating theaters, and a staff capable of performing any medical procedure short of organ transplantation. Fleet tugs still tow ships, as well as backing up the salvage ships in their mission of recovering objects from the sea bottom, supporting divers, and operating underwater vehicles. Read more...

When US designers finished the North Carolina class, their first since battleship construction resumed, they weren't entirely happy with the result. It was a ship armored against 14" guns in a world where the escalator clause had just come into force, allowing future battleships to be built with 16" weapons. And while it would seem that the treaty limit of 35,000 tons would preclude substantial improvements over the North Carolina, the preliminary design team, lead by Captain A. J. Chantry, produced a class that was by far the best of the treaty battleships and arguably superior to any battleship ever built outside the US.

Massachusetts of the South Dakota class in 1944

When design work on what became the South Dakotas began, it looked like they would revert to the traditional American type, slow and heavily-armored. The initial requirement was for a speed of only 23 kts, based on the estimated speed of the Japanese battle line. However, in late 1936, US intelligence became aware that the reconstructed battleship Nagato had made 26 kts on trials, and a speed of 27 kts swiftly became the standard going forward. Read more...

In 2010, my family took a spring break road trip that culminated in Dayton, OH, home of the National Museum of the United States Air Force. The visit was somewhat spoiled when the Fatherly One and my brother got sick and had to spend all day in the hotel, but Sister Bean and I were able to spend the whole day at the museum.³ This was a while ago, and there have been some changes since then, most notably moving the R&D/Presidential Gallery from being on-base to a new hangar at the museum proper, but the place was so amazing I have to plug it here.

The Cold War Gallery⁴

Website

The WWII Gallery

Dayton has basically every plane ever flown by the US Air Force or its predecessor, the Army Air Force, as well as a fair number that were captured or otherwise fell into their hands. It's the largest military aviation museum on the planet, and there's a lot of stuff in their collection that you can't find in many other places. Highlights include the only surviving XB-70 Valkyrie, a B-36 Peacemaker⁵ and Bockscar, the airplane that dropped the atomic bomb on Nagasaki. There are fighters, including everything from the rare and very interesting F-82 Twin Mustang to the F-22 Raptor, as well as transports, trainers, and even oddities like a bunch of old presidential aircraft, including the first Air Force One. Read more...

Weather has always been of the first importance at sea. In the age of sail, the reasons for this were obvious, but while officers no longer have to worry about the weather gage,⁶ they still must consider what wind and wave will do to their ships, and to aircraft they may be attempting to operate. And ships today must fight in conditions that would have had Nelson's captains looking to the survival of their vessels.

A Coast Guard Cutter battles heavy weather in the North Atlantic during WWII

The biggest effect of weather is on the motion of the ship. Besides the obvious motion of rolling, pitch and heave⁷ are also important to the efficiency of the crew, although in different ways. Any physical activity, such as loading a gun, is made substantially more difficult in cases of high lateral acceleration. This is only loosely related to the actual angle of roll, as a ship with a large metacentric height might roll to angles nearly as great as a less stable ship, but the lateral accelerations will be substantially higher as it snaps back upright. High roll rates also produce serious problems for fire control, although this is difficult to decouple from the effects of acceleration. Even mechanical systems like modern power-worked guns lose efficiency rapidly in these conditions. Read more...

It's our regular open thread. Discuss anything you want, even if it's not related to naval matters.

In 1937, the BBC dispatched a retired naval officer by the name of Thomas Woodrooffe as a correspondent to the fleet review at Spithead. He was to describe the spectacle from high on the bridge of HMS Nelson, with his words relayed in real time to listeners all over the country. Even better, Nelson was his old ship, and the officers went out of their way to make him feel welcome.

And when I say "make him feel welcome", I mean "lit up by fairy lamps" that he got very drunk. Before he went on air. The result is truly hilarious:

The Fleet's Lit Up

Woodrooffe got off with only a week's suspension, and continued to work for the BBC for several years.

Overhauled posts include Engineering Part 3 and Part 4, The Bombardment of Alexandria, my discussion of military pricing, the last part on amphibious warfare and Jim Pobog's story of the Late Night Forward Pumproom Test

In early April, 1982, Argentina invaded the Falkland Islands, a few desolate rocks in the South Atlantic, and the British mobilized their fleet in response. The carriers arrived off the Falklands on May 1st, swiftly defeating the Argentine Air Force. The Argentine Navy tried to interfere the next day, but withdrew after the cruiser General Belgrano was sunk by a submarine. Two days later, the Argentines struck back, sinking the frigate Sheffield with an Exocet missile. The next two weeks saw a siege of the islands while the British waited for their amphibious force to arrive.⁸

Fearless in San Carlos Water

Planning for the amphibious assault had begun while the task force was still on the way to Ascension, and Admiral Woodward's staff discussed a number of different options. The idea of a direct assault on the area around Port Stanley was quickly ruled out. While it was undoubtedly the most important location on the islands, this had led the Argentine garrison to concentrate most of its strength around the city. Amphibious operations are extremely difficult, and the British didn't think they had the strength to make a frontal attack. Another plan was to land on the lightly-held West Falkland and use it to either force a settlement or as a base for the recapture of East Falkland. This was also ruled out, as it would have placed the beachhead closer to the mainland air bases, raising the risk of air attack, and required a second landing on East Falkland later on. Besides the peril of the landing itself, this would have also pushed the end of operations back into late June, when severe winter weather would have made continued operations very difficult. Several different beaches on East Falkland were examined, and the planners eventually settled on San Carlos Water, a bay off Falkland Sound in the northwest corner of the island. Read more...

Neal Schier has returned with a sequel to his earlier post on why airline delays happen, looking at how delays get untangled.

Airline delays – how do they put it all back together?

Ah, airport delays — truly the Gordian Knot of the air transportation system. We all have experienced them and know how quickly they can grow into an unwieldy mess. What might start as a 30-minute departure delay for one flight, can sometimes end up in scores of cancellations—one of which, unfortunately, might be yours.

Now, if we were Alexander the Great, we could simply draw our sword and cut the knot in two. Instead, the airlines and the Air Traffic Control (ATC) authorities are left to unravel that knot thread by thread in order to “recover” scheduled air service.

Imagine you are at O’Hare airport and a winter storm starts to pound Chicago with heavy snow, ice, and strong winds. As you look out the terminal window it looks as if it is pouring snow it is coming down so fast. The giant snow plows are, of course, already at work and moving immense amounts of the snow, but there is a lot of ground to cover and progress is slow. Read more...

Even as the shattered hull of the Italian battleship Roma, sunk by German guided bombs, slipped beneath the waves, a vast armada of Allied warships was putting troops ashore to gain a foothold on the Italian mainland. The Germans, desperate to stop the invasion, turned their new weapons on the fleet.

Philadelphia off Salerno

The first sorties against the invasion fleet were flown at dawn on September 11th, two days after it arrived off the beaches. They were flown by aircraft carrying Fritz-Xs, intended to sink the cruisers providing vital fire support for the troops struggling to establish the beachhead. The first target was the Dutch gunboat Flores, which was badly damaged by several near-misses but not sunk. It is likely that they intended to target the nearby cruiser Philadelphia, who was targeted a few hours later by the second Fritz-X sortie. One missed by only 15m, but the ship emerged undamaged. Read more...