parsifal
Colonel
I could be wrong but that proposal probably carried no armor or self sealing tanks. The provision of which would affect bomb load or range or both. what kind of defensive turrets? The DeHavilland method of construction was not the normal aircraft wooded construction and British manufacture of wooden aircraft in the 1930s was not so great that a vast surplus of experienced wooden aircraft workmen were available. Much is made of the ability to use workmen from the furniture industry. I wonder how much of that was propaganda. I know some companies contributed and did well but not every table maker could make airplanes. A big hang up when trying to build a bomber force of hundreds if not thousands of aircraft are all the bits and pieces. Landing gear capable of dealing with 40,000lb and up aircraft, brakes, Hydraulic systems that will be needed regardless of airframe material. Spitfires got 3 pitch props because the constant speed units were going to the bombers. I think trying for a big wooden bomber would have been about the same as a metal one, no earlier into service but no later.
Once again, we dont need to think, or speculate. The evidence is there if we look for it. Design work on the Avro Manchester began in 1936, infact some design work had already commenced even before the issue of the official specification. The plane was first flown in July 1939, and entered squadron service in November 1940. It had taken over 4 years to get from specification to service delivery stage.
In comparson, the specification for the mosquito was issued in early 1940. it took just eight months to get to first flight stage. I am unsure of its squadron entry, but it was first used operationally in September 1941, so i guess that will have to do. So 18 months to 48 months. i hardly think that is comparable. And this can be done for aircraft after aircraft, including those developed under wartime expediency conditions (look at the typhoon and the firefly for example)
Another claim is that there was no real benefit to wood construction, and wood was in short supply. On both counts I am highly sceptical, but i do know that there were shortages in aluminium smelting and working capability in the British aeroindustry. nobody argues about that. everybody knows that the Brits were short in their metal working and aluminium smelting industries.
So lets have a look at the alleged wood shortages and the lack of gain due to use of non-allied trades in the construction of the airframe. I dont think that anyone is arguing that it takes less time to build the airframe, or that it is any less difficult. But if it is accepted that Britain was short of metal workers qulaified to work sheet aluminium, and if even one wood worker could be used to build the airframe instead of the tradesmen in short supply, then there is a benefit to working in wood. In fact, in Australias case, the production of the 212 Mosquitoes in 1945 was a free bonus, that had minimal effect on our other programs for that very reason. We could utilize wood working trades to fabricate the airframe and skin, with very little effect on airframe production of other types. Canada was I believe able to achieve simlar results.
Working in wood was a definite advantage in terms of getting the program up and running
.....The Halifax was also carrying the structure to deal with a 13,000lb load even when it wasn't fully loaded. A Halifax built to carry just 6000lbs could have had a smaller wing, smaller landing gear, lighter spars, fuselage, etc.
Of course, we are comparing a bomb truck to a gazelle. Lighten up the bomb truck, give it wings and it will fly just like the gazelle, Im not arguing that the Albatross was anything special, im arguing that the concenpt of the defended bomber was a faulty concept, and that even with 1938 technology it was possible to build a much faster and survivable design.
You also criticised that the Albatross would probably lack armour atr the specified weight. I tend to agree, bu then, all the prewar British bombers lacked armour. Armour wasnt added until after war broke out. I dont think there was a big degradation of bomber performance as a result of armouring. Not sure why (it should have) but it just didnt happen. maybe fuel grades? why would the albatross be different?
It also took a while for the proposal to actual settle down, while wiki claims " twin Merlin engined Albatross, armed with three gun turrets and a six-man crew.[10] It would carry 6,000 pounds (2,700 kg) of bombs to Berlin and return at 11,000 feet (3,400 m). It had a total weight of 19,000 pounds (8,600 kg), a top speed of 300 miles per hour (480 km/h) and cruise speed of 268 miles per hour (431 km/h) at 22,500 feet (6,900 m)." One can see that somebody was being a bit optimistic. After all a Handley Page Hampden weighed just under 19,000lbs Normal loaded, had two gun positions (not turrets) 4 men, a top speed of 254mph and a range of 1850 miles with a 2,000lb load. Or compare it to a an Early B-25 without power turrets. A latter proposal according to one source called for " A two Merlin compromise design was arrived at on 11 August, with a bomb load of 4,000 lb., a top speed of 260 mph and a range of 1,500 miles" this in 1938. Ramping up supply hits the same roadblocks as every other program. All the bits and pieces that go into any airplane regardless of the air-frame material. And you still need jigs and fixtures wither you are building in wood or metal.
maybe, but then perhaps we should compare it with its closest relative, the mosquito, which succeeded it and was in fact based on that airframe. With a fully loaded airframe weight of around 20000 lbs with two Merlin XXI engines rated at 1230HP had a top speed of 360mph (fully loaded). As you have pointed out, you should need something like 60% more power to go from 300mph to 360mph, if you design in the "slow lane" . If an aircraft that is its closest relative can travel at 360mph, on maybe 2-300 more HP, then I dont think the company was being ambitious at all when they said they could get 300mph out of the DH91. The fact that handley page or indeed North american didnt achieve anywhere near that speed with their designs is just confirming that the specs and the respective bureaucracies that they were working for didnt place too much importance on speed, whereas DeHavilland had given speed a high priority, as did the Breguet team designing the Bre 482, and the germans working on their Snellbomber programs. Your logic here is not good......picking a design (or designs) built to the official specs....the very thing that IS the problem, and then saying "see, I told you, its not possible to get that much speed out of that design because the designs that were built to that spec with the same weight and engines couldnt do it." But what is missed in this argument is that other designs, also of the same weight and using engines not much more powerful achieved a substantial lift in top speed.
Maybe you have different sources than I do. According to the books I have the French didn't do it. Not only didn't they fly in 1940 (one flew in 1947) but the proposed bomb load was 5500lbs not 8000lbs. Max speed with 1940 engines was estimated at 326mph. Cruise speed was 248mph, range not given but with the 5500lb load full fuel was supposed to be 693imp gallons. Not a lot for four 1100hp engines. More fuel meant less bombs.
The 350mph (or above) speed was achieved post war but the engines offered 1500hp for take off and hundreds more hp at altitude than the 1940 engines.
This goes back to the technological reason. The Merlin X engine doesn't really offer the performance needed for the concept to work. The Merlin XX does, an extra 20% or more of power at 20,000ft for less than 50lbs per engine. In 1938 (Hooker goes to work at R-R in Jan) the XX isn't even a speck on the horizon and nobody's engines offer the power to weight at 20,000ft that the Merlin XX will in under two years.
I agree with for first flight dates and the max bomb loads. However the aircraft was almost ready for first flight May 1940, and in all probability would have entered service later in 1940. In gerneral concept and capability it was remarkably similar to the Albatross bomber proposal
My sources do not agree with yours with regards to top speed. According to Green the top speed was 350mph, which accords to the figures given in wiki and Breguet Br 482 - Bombardier lourd - Un sicle d'aviation franaise. . Both Green and the french Aviation website state that these speeds were attained using the Hispano Suiza 12Z engines, rated at 1350hp. These replaced the Gnome Rhone 14L engines in the 1940 prototypes, and were used in the 1947 test flights, because of technical holdups with the GR 14L engines prewar.
The speed attained in the 1947 test flights as i understand it was 350mph on these engines. We cannot make much further analysis, because the type did not progress much beyond that point, and was scrapped in 1950.
Once again, we dont need to think, or speculate. The evidence is there if we look for it. Design work on the Avro Manchester began in 1936, infact some design work had already commenced even before the issue of the official specification. The plane was first flown in July 1939, and entered squadron service in November 1940. It had taken over 4 years to get from specification to service delivery stage.
In comparson, the specification for the mosquito was issued in early 1940. it took just eight months to get to first flight stage. I am unsure of its squadron entry, but it was first used operationally in September 1941, so i guess that will have to do. So 18 months to 48 months. i hardly think that is comparable. And this can be done for aircraft after aircraft, including those developed under wartime expediency conditions (look at the typhoon and the firefly for example)
Another claim is that there was no real benefit to wood construction, and wood was in short supply. On both counts I am highly sceptical, but i do know that there were shortages in aluminium smelting and working capability in the British aeroindustry. nobody argues about that. everybody knows that the Brits were short in their metal working and aluminium smelting industries.
So lets have a look at the alleged wood shortages and the lack of gain due to use of non-allied trades in the construction of the airframe. I dont think that anyone is arguing that it takes less time to build the airframe, or that it is any less difficult. But if it is accepted that Britain was short of metal workers qulaified to work sheet aluminium, and if even one wood worker could be used to build the airframe instead of the tradesmen in short supply, then there is a benefit to working in wood. In fact, in Australias case, the production of the 212 Mosquitoes in 1945 was a free bonus, that had minimal effect on our other programs for that very reason. We could utilize wood working trades to fabricate the airframe and skin, with very little effect on airframe production of other types. Canada was I believe able to achieve simlar results.
Working in wood was a definite advantage in terms of getting the program up and running
.....The Halifax was also carrying the structure to deal with a 13,000lb load even when it wasn't fully loaded. A Halifax built to carry just 6000lbs could have had a smaller wing, smaller landing gear, lighter spars, fuselage, etc.
Of course, we are comparing a bomb truck to a gazelle. Lighten up the bomb truck, give it wings and it will fly just like the gazelle, Im not arguing that the Albatross was anything special, im arguing that the concenpt of the defended bomber was a faulty concept, and that even with 1938 technology it was possible to build a much faster and survivable design.
You also criticised that the Albatross would probably lack armour atr the specified weight. I tend to agree, bu then, all the prewar British bombers lacked armour. Armour wasnt added until after war broke out. I dont think there was a big degradation of bomber performance as a result of armouring. Not sure why (it should have) but it just didnt happen. maybe fuel grades? why would the albatross be different?
It also took a while for the proposal to actual settle down, while wiki claims " twin Merlin engined Albatross, armed with three gun turrets and a six-man crew.[10] It would carry 6,000 pounds (2,700 kg) of bombs to Berlin and return at 11,000 feet (3,400 m). It had a total weight of 19,000 pounds (8,600 kg), a top speed of 300 miles per hour (480 km/h) and cruise speed of 268 miles per hour (431 km/h) at 22,500 feet (6,900 m)." One can see that somebody was being a bit optimistic. After all a Handley Page Hampden weighed just under 19,000lbs Normal loaded, had two gun positions (not turrets) 4 men, a top speed of 254mph and a range of 1850 miles with a 2,000lb load. Or compare it to a an Early B-25 without power turrets. A latter proposal according to one source called for " A two Merlin compromise design was arrived at on 11 August, with a bomb load of 4,000 lb., a top speed of 260 mph and a range of 1,500 miles" this in 1938. Ramping up supply hits the same roadblocks as every other program. All the bits and pieces that go into any airplane regardless of the air-frame material. And you still need jigs and fixtures wither you are building in wood or metal.
maybe, but then perhaps we should compare it with its closest relative, the mosquito, which succeeded it and was in fact based on that airframe. With a fully loaded airframe weight of around 20000 lbs with two Merlin XXI engines rated at 1230HP had a top speed of 360mph (fully loaded). As you have pointed out, you should need something like 60% more power to go from 300mph to 360mph, if you design in the "slow lane" . If an aircraft that is its closest relative can travel at 360mph, on maybe 2-300 more HP, then I dont think the company was being ambitious at all when they said they could get 300mph out of the DH91. The fact that handley page or indeed North american didnt achieve anywhere near that speed with their designs is just confirming that the specs and the respective bureaucracies that they were working for didnt place too much importance on speed, whereas DeHavilland had given speed a high priority, as did the Breguet team designing the Bre 482, and the germans working on their Snellbomber programs. Your logic here is not good......picking a design (or designs) built to the official specs....the very thing that IS the problem, and then saying "see, I told you, its not possible to get that much speed out of that design because the designs that were built to that spec with the same weight and engines couldnt do it." But what is missed in this argument is that other designs, also of the same weight and using engines not much more powerful achieved a substantial lift in top speed.
Maybe you have different sources than I do. According to the books I have the French didn't do it. Not only didn't they fly in 1940 (one flew in 1947) but the proposed bomb load was 5500lbs not 8000lbs. Max speed with 1940 engines was estimated at 326mph. Cruise speed was 248mph, range not given but with the 5500lb load full fuel was supposed to be 693imp gallons. Not a lot for four 1100hp engines. More fuel meant less bombs.
The 350mph (or above) speed was achieved post war but the engines offered 1500hp for take off and hundreds more hp at altitude than the 1940 engines.
This goes back to the technological reason. The Merlin X engine doesn't really offer the performance needed for the concept to work. The Merlin XX does, an extra 20% or more of power at 20,000ft for less than 50lbs per engine. In 1938 (Hooker goes to work at R-R in Jan) the XX isn't even a speck on the horizon and nobody's engines offer the power to weight at 20,000ft that the Merlin XX will in under two years.
I agree with for first flight dates and the max bomb loads. However the aircraft was almost ready for first flight May 1940, and in all probability would have entered service later in 1940. In gerneral concept and capability it was remarkably similar to the Albatross bomber proposal
My sources do not agree with yours with regards to top speed. According to Green the top speed was 350mph, which accords to the figures given in wiki and Breguet Br 482 - Bombardier lourd - Un sicle d'aviation franaise. . Both Green and the french Aviation website state that these speeds were attained using the Hispano Suiza 12Z engines, rated at 1350hp. These replaced the Gnome Rhone 14L engines in the 1940 prototypes, and were used in the 1947 test flights, because of technical holdups with the GR 14L engines prewar.
The speed attained in the 1947 test flights as i understand it was 350mph on these engines. We cannot make much further analysis, because the type did not progress much beyond that point, and was scrapped in 1950.