A cheaper replacement for the Avro Arrow, the Avro Crossbow is built around an improved and enlarged Iroquois engine called the Orenda PS. 16 Huron. While peaking at mach 1.84, far from the Arrow supposed 2.2, the Crossbow was not only much cheaper with a single engine but also had a longer combat range of 460 nautical miles (850 km) and a service ceiling of 15 000 m.
A dual seat, it possessed a powerful radar and guidance/tracking systems for the AA Velvet Glove homing missile operated by the copilot.


The Avro Crossbow CF-106 Mk.2 was made following re-tech after the first Crossbow operations. Both its role as a long range interceptor and Velvet Glove platform meant that it needed a larger and more powerful radar. An improved radar and thus radar cone was installed but despite the engineers best efforts to help the air flow, the much bigger cone drastically reduced the air intake and the plane had trouble at higher altitude. The engineers had to install side air intake to increase the airflow, their low profile allowed the Avro Crossbow to keep its performance. While these modifications did nothing to help with the plane complexity and high cost, it made it a unrivaled platform, allowing it to stay relevant and useful in its primal role even to this day.

An Air gunship, used before motorized artillery to support army advance with cannon fire
The arrival of fighter airplane and the inevitable motorization of artillery eventually ended their golden age, although they were still used as port interdiction against ennemy ship, until the arrival of Air and sea carrier ended that career too.
A canadian navy that, before WW2, realized that they would need a way to protect the Atlantic against german u-boat. They bought old freighters and repurposed them into escort carrier, with a dozen planes, a mix of Hurricanes for attack and protection and Swordfish to scout and chase down ennemy submarine. Called the ''converter class'', five of them were planned but at the outbreak of the war, only the Protector (former SS Londonerry) was finnished and combat ready.


With the lightning fall of France in 1940, the Canadian navy found itself catapulted at the forefront of the war way sooner then they expected. Their Converter-class project, hampered by the lack of funding and adequate ships, fell short of its goal of five converted carriers, with only the HMCS Protector being finished, supplied and combat-ready. The next in line, the HMCS Defender, was still in Halifax's shipyard, stripping the old SS Beaverford from its structure and modifying it into an escort carrier. With the British Isles alone in Europe, they needed all the resources available to continue the fight, and that meant bringing and protecting the vital Atlantic supply line, to keep it open. The HMCS Defender conversion's was accelerated, with the main structure kept and simply strengthen to save time and its crew beginning to train in a ship still in construction.
In mid-october, the ship left its slip, with workers still in board to complete the last details, for a shake-down and practicing its pilots. Around Newfoundland, they spent a week making mock attack on buoy before being recalled in emergency in Halifax. They were to protect the convoy SC-6 from Sydney, Nova-Scotia toward Liverpool. They only had time to refuel and drop the workers before meeting the rest of the escort. Desperately short on escort ship, the Royal Canadian Navy did not had the luxury of keeping one of its rare carriers on sea trial, no matter how vital they were.
All through its career the HMCS Defender would suffer from this, needing no less then three refits, one to modify and strengthen its watertight compartments (that were supposed to also serve as anti-torpedo protection), install dampeners to reduce its engine vibrations (known to affect the fuel lines for the planes, many of their screws and joints suffered) and even ballast to compensate for its top-heavy structure.

Nonetheless, like the HMCS Protector, the HMCS Defender would prove, with its Hurricane/Swordfish mix, to be a deadly opponents for the German u-boats. So vital to the safety of convoy, Converter-class carriers were often reserved for the most important cargo, such as fuel and foods.


In 1933, the former SS Astrée of the Compagnie de Caen was put to sell and both Canada and Italian owners were bidding for the ship, for two different reasons. The Italian bidders were obviously looking to own the ship for cargo hauling but the Canadian government was looking to convert the ship into a potential escort carrier. The Canadian government finally won the ship and made it cross the Atlantic to reach Halifax. While the construction slip was already occupied by the former SS Londonberry and the SS Beaverford being inspected and cleaned, the SS Astrée waited in a dry dock of the Halifax Shipyard of the Dominion and Steel Corporation while funds were made available. While inspector reviewed the ship structure and small repairs and maintenance took place, it was not before 1936 that the Astrée finally shed its civilian skin to wear its military identity as the new HMCS Escorter when the HMCS Protector (ex-Londonberry), was finally completed.
But the Converter-class program was always low on funds and priority, many politicians dragging feets when it came to spending more money on carriers, especially due to both the need in airplanes, pilots and sailors, many preferring investing in cheaper Corvette and Frigates. Especially as the old structure of the Protector meant that many refits were needed, workers from both the Defender and Escorter were frequently transferred to save cost. In 1939, the HMCS Defender was 70 % completed while the Protector had only its interior redesigned when the war was declared. The Phoney war and the lack of apparent menace meant that the pace was not accelerated, in fact, the Canadian navy gearing up for war meant refitting or readying many old ships, competing with the two soon-to-be carriers. With the fall of France and the ''convoy panic'', all the efforts were transfered to the Defender to make sure that she would enter service as fast as possible, meaning that the Escorter's workers were transfered to help.
With the Defender launching in 1940, efforts focused back to the Escorter and even new potential ships. In June 1941, the ship would launch and do many sea-trials before being considered ready for operations in late October. Thanks to the lessons learned from both carriers (especially the Defender numerous refits), the HMCS Escorter would be considered as the most advanced first generation Converter-class carrier. The munitions and spare parts crates were finally removed, a catapult was installed and the armament fixed to 8 single-mount 20mm and 4 single-mount 40mm Bofors (the old 4in gun, already absent due to a lack of space on the Defender, were abandoned since the main threat was isolated as either submarines or aircraft).


Due to the Gloster Meteor taking too much time being built, Britain was forced to find a solution to combat the growing threat of German V-1 and Messerschmitt Me 262. The solution would be to modify the Supermarine Spitfire to add two Rolls-Royce B.23 Welland jet engines, advance the canopy, arm it with 4 20mm cannons and strengthen the tail. Using as much pre-existing production lines as possible, the new Supermarine Comet was put into service before the first Meteor reached its first squadrons. Cheap and easy to mass-produce, it began to replace the Spitfire as the main British interceptor. Despite "flying like a brick" and being less maneuverable then its main nemesis the Me 262, it was similar in speed and much more abundant in the sky. Its quick arrival in service allowed RAF pilots to fight back against German machines on a much more leveled playing field. But despite its gallant service, it did have many issues like a short range and its wings having a tendency to rip themselves off the plane if an acceleration was too brutal, like in a steep dive at full throttle.

With the end of the war and the arrival of a new generation of jet planes like the Mig-15 and F-86 Sabre, the Comet will quickly be removed from active service, being replaced by the Supermarine Swift. Ironically, its the experience gained in designing and operating the Comet that allowed Supermarine to design its replacement. In another twist of irony, after having its thunder stolen by the Comet during the war, the Gloster Meteor would have its revenge by outliving its main competitor. Much bigger, the Meteor was also a much more modifiable and versatile platform that was adapted to many roles like interception, recon, tactical support and short range escort.

In the end, actually very few Comet survived to this day. By sharing the same engine with the Meteor, they were frequently cannibalized to cheaply keep these ones flying during tight military budget times. While less then a dozen of them survived as museum pieces, a few collectors made "Frankenstein Comet" by modifying a Spitfire and adding Meteor engines to it and recreate a new plane from scratch, these ones are the only one still flying to this day.
I know that question comes a bit late but I only now found the thread.
I have always been a fan of airships and am currently tinkering with a very soft-AH ASB scenario that involves them, can you give some specifics on the canadian air carrier? It looks like it uses a multi-hull setup which in general is pretty smart for any kind of very high load airship but how do you solve the issue of the very high center of gravity from the proper carrier deck on top, or does the design just ignore that (which is totally fine on something as inherenty unrealistic an an airborne aircraftcarrier)?
I was inclined to go with a more USS Macon style of trapeze arrangement on the bottom, but strengthened for heavier planes and somewhat "spring-mounted" to counter the higher relative velocities.

I`d also like to know what kind of armament your gunship carries, my own calculations where that the max you could get on a not-ultra-gigantic airship was ~2-3 6-inch cannons in minimally armored turrets.
I know that question comes a bit late but I only now found the thread.
I have always been a fan of airships and am currently tinkering with a very soft-AH ASB scenario that involves them, can you give some specifics on the canadian air carrier? It looks like it uses a multi-hull setup which in general is pretty smart for any kind of very high load airship but how do you solve the issue of the very high center of gravity from the proper carrier deck on top, or does the design just ignore that (which is totally fine on something as inherenty unrealistic an an airborne aircraftcarrier)?
I was inclined to go with a more USS Macon style of trapeze arrangement on the bottom, but strengthened for heavier planes and somewhat "spring-mounted" to counter the higher relative velocities.

I`d also like to know what kind of armament your gunship carries, my own calculations where that the max you could get on a not-ultra-gigantic airship was ~2-3 6-inch cannons in minimally armored turrets.
Thanks, both airship are indeed multi-hub, with a larger central one and two side ones that not only allow more weight but additionally serve as stabilizer (hence helping with top-heavy structure).
The gun-airship had 2 twin 6-inch cannon turret with only anti small arms armor.

During WW2, Vickers tried to enter the heavy bomber game but failed when the Vickers Windsor turned out to be a failure, not supported or needed by the RAF. Instead they turned their Vickers Wellington into fast heavy bombers with Halifax surplus wings from de Havilland factories and a modified tail. The newly born Vickers Liverpool was, however, walking on a tight rope; the RAF and the ministry of production were fearing that this new bomber, sharing the Bristol Hercules engines, would compete with the already well established Handley Page Halifax. Vickers wisely chose to instead push for powering it with Roll-royce Merlin XX, proposing to equip the Vickers Liverpool with the old Merlin XX from upgraded Halifax which received Hercules engines. Under the suspicious but tolerating eyes of the RAF and MoP, Vickers started a secondary line of production in its factories for the Vickers Liverpool.

Quickly, its speed, long range, high service ceiling and maneuverability began to be noticed and appreciated by the crew and pilots who had to fly bombing missions without continuous fighter escorts. Liverpool formations quickly adapted to the strategy of Dive-and-Fly: to start from high altitude (8500 m), dive back to medium altitude (<3000 m) right on the target and after bombing it, use its speed (480 km/h) to fly back into high altitude. While successful at first, they also began to gradually take heavier casualties over time on missions over Germany (as the germans began to keep Bf 109 in high altitude around cities and important sites, who used their superior service ceiling to dive on the climbing Liverpool), they had to begin to shift to less defended targets and night raids. Their belly turret were being useful against Heinkel He 219 trying to use Schräge Musik, upward firing guns, to shoot down bombers from bellow. This led to the Liverpool being the main British night bomber for the 43-44 years, leading and succeeding in many nocturnal missions.

Heavily armed for a British bombers, the only real draw-back from the Vickers Liverpool was its small 2000 kg payload, inherited from the Wellington bomb bay, tiny for a 4-engine bomber, limiting its strike capability. Due to its limited production line, despite Vickers attempt to convert damaged Wellington and Halifax into Liverpool to accelerate production, the Vickers Liverpool could not make up its small payload with larger formations. Armored or buried targets had to be left to Halifax and Lancaster who had a larger payload and bomb variety, thus the Liverpool were relegated at the end of the war to the controversial "Dehousing" strategy of Professor Lindermann, where their smaller capacity were outset by the effect of their incendiary payloads. With the limited numbers of Bf-109 available to Germany in these late years, the Dive-and-Fly tactics were gaining efficacy back and with P-51 Mustang escorts, the Liverpool formations were those with the smallest casualties rates.

At the end of the war, the had-hoc nature of the Liverpool played against it as they were quickly removed from production, with the remaining machines being slowly converted into civilian long-range cargo and passenger transport. Over-shadowed by the more prominent Wellington and Halifax in the public consciousness, it was however loved by their crews who had nicknamed it the "boomerang" for "when it flew, it came back", honing to the lower casualties rates of the aircraft compared to the other bombers.
In December of 1941, only 2 months after the HMCS Escorter departing on its first mission, the United States was struck by surprise by the Japanese Empire at Pearl Harbor, bringing them in the Second World War. With the arrival of the American industrial might and Navy on the side of the British Empire, the Canadian government expected a breath of fresh air regarding the Atlantic War. But with the American focus on the Pacific front, it would take time until their naval build-up would be able to divert ships and take over the Atlantic front from the Canadians.
But one thing that was available in growing numbers were the "Liberty Ships", British cargo ships modified to be mass-produced by the American shipyards. While the majority were planned for their original task, the Canadian government asked and received four Liberty ships to study the possibility of turning them into Converter-class Escort carriers. During much of 1942, the Halifax Shipyard of the Dominion and Steel Corporation would not only work on the conversion but also improve on the original design and increase the standardization of the second generation of Converter Escort Carrier. In February 1943, the first result of the Canadian new-found experience in carriers would be christened as the HMCS Guardian and go on sea trials as work accelerated on its sister-ship, the future HMCS Custodian. But aboard the HMCS Guardian, the old workhorse of the Canadian naval air-corp; the Sea-Hurricane and Swordfish had been replaced by newcomers: the TBF Tarpon Mk.I and F-4 Martlet Mk.V, the British variant of the American Grumman TBF Avenger and Grumman F4F Wildcat.
But as the training period was coming to a close, with the Canadian pilot used to their new ship and birds, the new HMCS Guardian was thrown into the brutal Atlantic Battle, as the Nazi U-boat fought tooth and nail to prevent the Allies to build-up forces in England and North-Africa to invade and put an end to their evil empire. With the HMCS Custodian following a few months later, both ships would protect troop transport vessels as well as armament, supplies and food cargo. These ships, coupled to the other Converter Escort Carrier, would prove to be the most vital assets of the ally convoy and despite the air escort not being as deadly to German submariner as believed, they were essential to force them to dive far from the convoy and cut contact with their wolf pack. Nobody could know for sure how many brave ally sailors and ships were saved by the floating air umbrella offered by the Canadian carriers but one thing that was sure was that a convoy protected by a carrier, usually suffered less then 5 % casualties compared to a corvette-only protection of around 25 %.
In 1944, the US Navy was fully capable of protecting all convoys with enough destroyers and the hunt for German u-boats had broke much of the dreaded wolf-packs. Despite the submarine threat still being present until the end of the war, it didn't justified the conversion of the two remaining Liberty ships into carriers so they were reverted back into cargo. The Canadian shipyards were then focused on making corvette and cargo ships to better support the war in Europe and keep the allies soldiers supplied.
But the Converter Escort Carrier would stay in operations until the end of the war, and a third generation was planned with better RADAR, communication array and sonar when the end of hostilities put an axe in the project. In fact, of the fiver Coverter carriers, only the Guardian and Custodian would stay in the RCN service as the three others, the Protector, Defender and Escorter, were all suffering from hull fatigue, due to the longevity of their previous civilian identity, the stress of the war conversion and heavy usage. The Guardian and Custodian would stay in service until 1957, when the HMCS Bonaventure carrier would enter RCN service, as a fully modernized, dedicated carrier, it was much more suited then the old Converters who were finally laid down.



Monthly Donor
So does the Liverpool employ the same lattice framing as the Wellington? A top speed of 298 mph is pretty good, but with a bomb load sometimes worse than a Mosquito, you have to ask what they could do to improve ceiling, climb, range and top speed. Looks pretty short for a four engined bomber too. Take-offs would be hard with that little tail leverage? Just checked, yours is same length as Lancaster (102ft wingspan, Merlins, 20'6"tall). Mine the same as a Shackleton (120ft wingspan, Griffons, 17'6"tall).

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