Improved interwar RAF/RN ASW

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So, as I see it, aviation in Europe between the wars is more driven by military than civil needs. And the question is then how to get from the biplanes of 1930 to the Superfortress of 1942.
The British did try to push the envelope at times with the Empire Mail service. But that does not result in large orders per design type.

It also sometimes causes stagnation. There were multiple British design teams chasing different requirements. African routes needed different planes than European routes and routes to Africa required different aircraft again and..................
It may be good and it may be bad, a lot of design teams got experience but it many cases the aircraft were not 'competitive' except in the sense that on some routes they were competing with another countries national airline. Which were flown by aircraft produced by the home country if the country was big enough to have an aircraft industry.

The British were not helped at times in the early 30s by a certain magazine editor and others who believed things that had no factual basis (like biplanes would climb faster than monoplanes).

Setting some of your short city to city schedules on whither you could get a decent lunch served and eaten before the plane landed might not have been the way to advance aeronautical knowledge

The greater distances in the US did make speed a higher priority for a number of reasons. On short flights a faster plane could get in more flights per day to return investment quicker.
On longer flights a faster plane could fly more stages or longer ones on multiple day/overnight flights.

for domestic flights the British rail service was a stiff competitor since there were a number of express routes between major cities. Cutting an hour or so off those train trips was not going to cause a mass boom in air travel. For the US the trains took just over 20 hours to go from New York to Chicago so even if the plane needed to stop once for fuel a "fast" plane could make the trip in under 5 hours.

Boeing was disappointed when they only sold 75 of 247 model. Very few British airliners sold more than 10 planes. The same could be said for French and Italian aircraft.

things over lapped but the MacRobertson Trophy Air Race of Oct 1934 is an indicator, The DH 88 was a marvelous airplane but the Boeing 247 which finished 3rd (and was full of fuel tanks) was narrowly beaten DC-2 which was flying passengers to and from standard stops on it's route. The DC-2 also got lost and bogged down in the mud on landing and was pulled out by residents of the town.

This is 1934, it is a commercial airliner in service with a customer, The wings and tail (and engines ? ) were used in those obsolete B-18 bombers in 1940-42. The B-18 was obsolete in 1940. But the US aircraft industry sure didn't believe the B-18/ DC-2 was world standard at time.
 
Can't think of his name at the moment, he was either the editor for Flight Magazine (or or one of the editors. )

One of his articles in the early 30s called the US bombers of the time a fad. I think they were the
XB-7

the YB-9

Not sure if the 3rd was the XB-8

or the Martin XB-907

Please note that all of the aircraft pictured had retractable landing gear and 3 if them (?) flew in 1931, they were all flying in 1932.

I think the article stated that British biplane bombers were better because they could climb better.
 
Getting back to ASW the British tried these at end of WW I.


The R class, good for 14 kts under water and 9 kts on the surface they were equipped with hydrophones to listen with 6 18in tubes to enable the Sub to fire a salvo at a German submarine. 12 were ordered, fewer were completed.
The first sub designed to fight other submarines instead of taking a chance pot shot as the enemy sub cruised by.
The technology of the time wasn't up to the job. The Hydrophones were short ranged and didn't allow for precise targeting. The propulsion system/s were not balanced. The single generator took many hours to recharge the battery. SO much that the batteries were charged from shore power. The boats were also difficult to control. a long tapered tail with single screw helped speed but turning and diving were difficult. After 1923/24 the two that were left were used as targets for the ASW school. On lasted until 1934.

For this discussion we can look at them several ways.
1. Tried that, didn't work, nobody will ever try that again, ever.
2. Tried that, didn't work well, keep an eye out in case somebody, somewhere, tries it again to use against us.
3. Tried that, didn't work well at the time, monitor sensors (hydophones/asdic) and batterys/electric motors/diesels to see if improvements make it worthwhile investigating again.

Going for number 3 requires some hindsight and in fact after WW II a number of smaller diesel electric boats were built that kinda/sorta followed them.
going for number 2 would seem to a prudent course, it doesn't cost much, if anything, and hopefully gives a bit of warning. Or at least keeps people thinking about what to do in case a fast sub shows up. British learned that converted trawlers weren't going to work against the fast subs. But since nobody else had fast subs it was only a theoretical problem.
During the 20s and 30s and lot of old British subs were scrapped. Rightly so as subs need a lot of maintenance and technology was getting better.
The 3 U class boats were originally designed to be un armed clock work mice for the ASW school, ordered in 1936 and laid down in 1937 they were given four/six 21in tubes and eight/10 torpedo's and a repeat class of 12 were ordered in 1939. But spending money on 3 clock work mice shows that the purse springs were getting bit looser.

going for number 1 is just sticking the head in sand.

What were the likely threats in the 1930s both strategic (enemies and enemy bases/routes, patrol length and such) and tactical (speeds, range, sub maneuverability, battery capacity)
and how do you counter them.
 
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The London Naval Treaty 1930 limited Britain, USA and Japan to 52,700 tons of submarines with each new vessel not allowed to exceed 2,000 tons. That was what drove much of the scrapping in the 1930s. It was needed to free up tonnage for new modern classes.

By Sept 1939 the RN sub fleet comprised:-

WW1 types - 9 H (410 tons) & 3 L (760 tons) class mostly used for training duties in Home Waters but which undertook some war patrols early in WW2.
Inter war patrol subs built from 1926-30 - 9 O, 5 P & 4 R class (1350-1475 tons) - 13 based Hong Kong, 3 in Med, 2 in Home Waters.
Thames class fast 22 knot surface speed boats (1850 tons) - 1 in home waters & 2 en route to Freetown.
Porpoise class minelayer (1520 tons) - 2 in Med, 3 at/en route to Hong Kong, 2 in home waters
S class (built 1931-37. 640 tons) - 4 in Home Waters, 8 in Med.
T class (1325 tons) - 1 + 2 working up in Home Waters (+12 building from pre-war building programmes)
U class (built 1937/38. 540 tons) - 3 in home waters

Submarines could be replaced after 13 years. The T class were intended as the successors to the O,P,R classes for service overseas. The first of the O class had already been placed in reserve pre-war only to be returned to service on its outbreak.

Plans for the 1939 War Programme called for concentration on building T/U class but 5 S class were introduced to maximise use of building facilities. The U class proved ideal for work in the shallower waters of the Med from early 1941. Following the outbreak of war with Italy the boats at Hong Kong were diverted to Home Waters and the Med.

The large number of patrol submarines at Hong Kong, were intended as a first line of defence against any Japanese fleet action against British interests at Hong Kong or by a strike south into the South China Sea.

Due to Coastal Command's inability to completely cover the Scotland / Norway gap half a dozen subs had to be deployed near the Norwegian coast to cover the gap.
 
Peter Masefield?
 
An excellent post. As you note DEs were being built at the expense of LSTs. The defeat of the U-Boats in May 1943 allowed that to be reversed with almost 1/3 of DE orders cancelled in September and October of 1943.




If you assume the shipping losses continue in 1943 at the same level as 1942 the merchant fleet doesn't catch up to its prewar size in the fall of 1943. Draw a horizontal line at the 1942 loss level thru the top graph you'll see that the deficit isn't erased until sometime in 1944.



In any case getting back to the earlier fleet size wasn't enough as the demands for shipping were greater than 1940 levels.
Also, the tanker situation was, as you note, worse than for cargo ships. An emergency program of converting Liberty ships into poor man's tankers was undertaken which was cancelled after the defeat of the U-boats.
According to "Fighting with Figures" from the Cental Statistic Office the British tanker fleet (vessels over 1600 gross tons) reached its peak on September 30, 1941, at 658 vessels. It hit its low of 507 on September 30, 1943, but never really rebounded after that reaching a new maximum of 536 on December 31, 1944.
As for demand, the tonnage carried by US tankers increased by almost 40% comparing the first 6 months of 1943 to the first 6 months of 1944.

If tanker losses were not gotten under control in 1943 the combined bomber offense doesn't get off the ground. If cargo ship losses continue something gets delayed
You also mentioned the other thing that doesn't get discussed often enough, the appalling casualties suffered by the Merchant Marine. The majority of these deaths occurred in 1941 and 42. I am surprised that the moral didn't shatter, and it may well have if losses had continued at such a high level in 1943. I think it would have been difficult to convince people to face the prospect of burning to death on a tanker or freezing to death in the cold Atlantic.
Churchill claimed after the war that the Battle of the Atlantic was the only thing that frightened him, but he didn't seem to be too concerned about it until the beginning of 1943.
 
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The British were not helped at times in the early 30s by a certain magazine editor and others who believed things that had no factual basis (like biplanes would climb faster than monoplanes).
Hi

Then again comparing the contemporary fighters, the monoplane Boeing P-26A and biplane Gloster Gauntlet there is not a lot of difference in performance:
P-26A - Max speed 234 mph at 7,500 ft, Initial Climb 2,360 ft/min., Service Ceiling 27,400 ft, Range 360 miles.
Gauntlet - Max speed 230 mph at 15,800 ft, Initial climb 2,300 ft/min. (9 mins to 20,000 ft), Service Ceiling 33,500 ft, Range 460 miles.
Going for monoplanes during the early 1930s did not necessarily mean a great increase in performance.

Mike
 
Well, there is some difference if you unpack things.

The P-26 used a 22 liter engine rated at 500hp for take-off but could make 575hp at 7,500ft.
The Gauntlet used a 24.75 liter engine rated at 640hp for take-off and 645hp at 15,500ft.

The P-26 was just under 3,000lbs and the Gauntlet was just under 4,000lbs
The P-26 was supposed to do 228mph at 15,000ft. Rough estimate of power about 490hp. (taking 2% per 1000ft from the 570hp figure)
P-26 range is variable, it did have two internal aux fuel tanks in addition to the main tank.

Yes they are contemporaries. Gauntlet was 33% heavier, Gauntlet had about 30% more power and had 7500ft higher critical altitude on the engine.

However for a different comparison of the Monoplane vs the Biplane see the YP-24


First flew in the Summer of 1931.
A 600hp Curtiss V-12 with no supercharger (sea level was at good as it got.)
Used a 292 sq ft wing, the Gaunlet used 315 sq ft of wing.
The YP-24 weighed 4360lbs and did 235mph height unknown to me. This plane used a wooden wing.

It was turned into this, the YP-25

Delivered to the Army in Dec 1932 with Metal wing and a turbo

Weight was 5110lbs and speed was 247mph at 15,000ft.
The turbo could maintain sea level power to 15,000ft. The engine itself had no supercharger. It was a single stage system.

Note the difference in radiators. The YP-24 used water, The YP-25 used Prestone (Glycol).
The YP-25 also got a reduction for the prop.
 
Let's put it this way, I bet that even in 1936 no one (who mattered) in Britain was able to foresee that before the end of the decade the country was going to be at war with Germany again.

Forgive the quick reference to Wiki, but even before Hitler assumed power Churchill had warned that if the Nazis gained power they would aim for war. To be fair there's no timeline attached t his prediction (i.e. he never predicted war by 1940) and so it doesn't meet your criterion, but it could be said that by 1936 Churchill understood the prospect of looming war better than most any British politician.

I suppose the question then becomes "did Churchill really matter in 1936?", and that is certainly open to debate; I'm of divided mind on that myself.
 
I bet that even in 1936 no one (who mattered) in Britain was able to foresee that before the end of the decade the country was going to be at war with Germany again.
Well, they key part to this was the "end of the decade". Leaving aside the nitpicking of 1939 or 1940 being the end of the decade there were a lot of people in 1936 that thought war with Germany was coming. One of the big reasons for the RAF expansion plans starting in 1934.

The Question in 1934 (or in 1936) was how soon, in the current decade or in the next decade.
Britain had lived by the 10 year rule since 1919.

"The Ten Year Rule was a British government guideline, first adopted in August 1919, that the armed forces should draft their estimates "on the assumption that the British Empire would not be engaged in any great war during the next ten years".

It was to expire in 1929 but Churchill had pushed for extension year by year in 1928.
However the economic problems of 1929 and later helped extent the rule until 1932 and the economic problems were strongly considered for several more years even if plans were being made for possible war within 10 years.
The Italian-Abyssinian situation was warming up although actual warfare wouldn't break out until 1934.
The Japanese take-over of Manchuria in 1931 and the withdrawal from the League of nations were the first outside indicators that peace was going to harder to maintain.
We won't count the British police actions in the North West frontier or the French and British meddling in the mid east in the 1920s.

US meddling in the Caribbean/South America didn't affect British defense spending.

German Annexation of Austria in March 1938 certainly changed the anticipated time line.
 
1929-1939 were Churchill's so called "Wilderness Years" when he was in Parliament but not in Govt. and no influence over anything. No one in the British Govt was planning for war in 1939 until 1938. 1938 is the critical year when everything went completely out of control and war in the short term becomes much more certain.

On the naval side, no real rearmament could happen before 1 Jan 1937, after expiry of the 1922 Washington Treaty. Admiralty plans were looking to the 1942 at the earliest, by which time there would be 21 capital ships (incl 7 modern units) in service plus 11 carriers (incl 7 modern units) and more building.

And this from Admiral Raeder's war diary of 3 Sept 1939:-

"Today the war against England and France, which the Führer had previously assured us we would not have to confront until 1944 and which he believed he could avoid up until the very last minute, began ...

As far as the Kriegsmarine is concerned, it is obvious that it is not remotely ready for the titanic struggle against England. To be sure, the brief period of time that has elapsed since the Agreement of 1935 has witnessed the creation of a well-trained and well-conceived force of U-boats, of which approximately twenty-six are currently ready for Atlantic operations, but these boats are still far too few to exert a decisive influence upon the war. The surface forces, moreover, are so weak and so few in numbers vis-à-vis the British fleet that the only course open to them-presupposing their active employment-is to show that they know how to die gallantly and thereby to create the basis for an eventual rebirth in the future".[1]

Chamberlain is much criticised for the Munich Agreement. But without it War may well have started in 1938. Then look at how Britain's defences improved in that extra year. Improvements to the radar network, Spitfires entering service etc. The question is whether those improvements would have exceeded the improvements in German offensive capabilities to make war in 1938 a better option. Those in Govt clearly thought not.
 
Sorry if I have missed bits within this interesting thread. It is a tough question. With hindsight many things could have been done differently. With the knowledge they had at the time could better decisions have been made between the wars? George Franklin's "Britain's Anti-Submarine Capability 1919-1939" is a well-researched and relevant text. I disagree with some of his conclusions but the book is the best primer. I find the nature of the interwar ASDIC exercises and training lacking in realism. Health and safety came first and this largely removed realism and the potential to learn from the exercises. Convoy escort training was inadequate despite what Franklin seems to conclude. But given the economic cost of rounding up tens of merchantmen it is hard to see how this could be overcome given the budget issues facing the UK. So the RN was poorly trained for an ASW campaign despite some keen ASW specialists such as Walker. Its escort ships in the late 30's were for the fleet not merchantmen. The nature of the war also took an unexpected turn early on with the loss of France. Should that possibility have been gamed? If it was what could be done about it within the limited UK resources? What other projects would be cut to generate funds?

I do think more realistic pre-war training even just with ASDIC and the effectiveness of depth charges would have provided information that could have lead to some different decisions. The RN was too optimistic about its ability to hunt and sink U-boats. The puny bombs equipping aircraft were also not tested adequately for destructive ability and accurate dropping.

I will say that the RN had an excellent commitment to training throughout the war and understood that it was better to use existing kit with well-trained sailors than constantly bring in new kit with extra bells and whistles. Operational research had an important role there.

Someone earlier asked about sonobuoys. I did write an article on them a couple of years ago. If anyone wants a copy PM me an email.

Not convinced about blimps. Terribly vulnerable if they came within AA range of a surfaced U-boat. Maybe they had a role but I'd use the funds on other things. Best book on them is by William Althoff "Forgotten Weapon: USN airships and the U-boat war". About the US but the lessons are there.
 
The RN was too optimistic about its ability to hunt and sink U-boats.
The US Navy was the same. In some pre war exercises if a sub was spotted (periscope track) the umpires declared it sunk.

Granted you can't drop live depth charges in training but 100% kills for spotting a periscope is very hard handicap for the subs to overcome and didn't promote good tactics on either side of question.
 
That is MV Mormacmail... being converted into AVG-1 USS Long Island (purchased for conversion after completion)!

HMS Archer, the second CVE built by the US was converted from MV Mormacland (purchased for conversion after completion). Designated BAVG-1 during conversion.
HMS Avenger was built as MV Rio-Hudson (purchased for conversion after completion). Designated BAVG-2 during conversion.
HMS Biter was built as MV Rio-Parana (purchased for conversion after completion). Designated BAVG-3 during conversion.
HMS Dasher was built as MV Rio de Janeiro (purchased for conversion after launching). Designated BAVG-5 during conversion.
USS Charger CVE-30 (ex-HMS Charger) was built as Rio de la Plata (purchased for conversion after launching), and converted for the RN before being returned to the USN. Designated BAVG-4 during conversion.
These had all been built for the American Moore-McCormack Lines, Inc., and were diesel-powered, and were built to the US Maritime Commission's standardized "Type C-3 cargo ship, diesel-engined variant design".

The succeeding Bogue class of 45 ships, which ushered in mass-production of CVEs, were based on the US Maritime Commission's standardized "Type C-3 cargo ship, steam-engined variant design".
HMS Battler was laid down as SS Mormacmail, and was purchased for conversion before launching. Designated AVG-6 during conversion.
HMS Attacker was laid down as SS Steel Artisan, and was purchased for conversion before launching. Designated AVG-7 during conversion.
HMS Hunter was laid down as SS Mormacpenn, and was purchased for conversion before launching. Designated AVG-8 during conversion.
USS Bogue AVG-9 was laid down as SS Steel Advocate, and was purchased for conversion before launching.
The next 18 (10 for the USN and 8 for the RN) were unnamed C-3 hulls acquired for conversion before launch.
The last 23 (all for the RN) were laid down to the converted CVE design.

The following 50 Casablanca-class CVEs were built to an improved version of the Bogue design, with changes enabled by being designed from the start as carriers.

The 4 Sangamon-class CVEs were converted from Cimmaron-class oilers built to the US Maritime Commission's standardized "Type T3-S2-A1 oil tanker" design, which had been subsidized by the US government for a more-powerful propulsion plant as "National Defense Tankers", designed "to conform to the approved characteristics for naval auxiliaries in speed, radius and structural strength", anticipating their militarization in the event of war (all 9 of the first 12 were taken into the USN in 1940, with 3 completing directly into naval service in 1939 - 23 more were completed for the USN in 1943-46).
USS Sangamon CVE-26 was completed as Esso Trenton for Standard Oil of New Jersey in early 1940, was later inducted into the USN in Oct. 1940, and was selected for conversion in Feb. 1942.
USS Suwannee CVE-27 was completed as Markay for Keystone Tankship Corporation in late 1939, was later inducted into the USN in June 1941, and was selected for conversion in Feb. 1942.
USS Chenango CVE-28 was completed as Esso New Orleans for Standard Oil of New Jersey in early 1940, was later inducted into the USN in May 1941, and was selected for conversion in Mar. 1942.
USS Santee CVE-29 was completed as Esso Seakay for Standard Oil of New Jersey in mid-1939, was later inducted into the USN in Oct. 1940, and was selected for conversion in Feb. 1942.

The later Commencement Bay-class CVEs (35 ordered, 19 commissioned, 2 completed but never commissioned, 4 scrapped on the slip and 10 cancelled before being laid down) were based on the T-3 tanker hull design, with changes enabled by being designed from the start as carriers.
 
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The puny bombs equipping aircraft were also not tested adequately for destructive ability and accurate dropping.
They weren't tested at all, or if they were it was after thousands had been ordered and manufactured which was more than a bit late.

When better explosives were developed the small bombs got priority in the hope that they would become at least somewhat useful. Which also points to the supply/logistics problems you can get into. Once you have tens of thousands of bombs either on order or in supply dumps and hundreds (if not over a 1000) aircraft equipped with racks or bays to hold them it is very difficult to refit, re-equip, and retrain to get them out of inventory.

Part of the problem with dropping was that they didn't have a bomb sight that worked at that low an altitude (equipment issue) so it was up to the pilots judgement (eye?) and with some of the planes having only two bombs the pilots often dropped from lower altitudes than they should have to get hits (training issue?) which sometimes meant the bombs hit the water at a too shallow and angle and they skipped/ricocheted of the water.
Noses on some AS weapons were modified to prevent skip/ricochet but that also took a while.
 

As Ewen highlighted, there's a difference between modernising one's armed forces to keep up with foreign trends and risk falling behind a potential foe, and preparation for war.

Granted you can't drop live depth charges in training but 100% kills for spotting a periscope is very hard handicap for the subs to overcome and didn't promote good tactics on either side of question.

Yup, a lot of whales and semi-submerged coastal rock formations have been sacrificed in the name of anti-submarine warfare!
 

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