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Most of us have seen claims online that the Bristol Hercules were optimized for multi engined, tractor-like bomber hauling rather than the rapid changes in throttle, supercharger, manifold pressure, attitude and altitude seen in single seat fighters. But there are many potential single engine application for the Hercules that were not fighters. There's also the case that in the Merlin and Griffon, Britain had two superlative liquid cooled inline engines. Is that it, is this why we see so few single engined aircraft powered by the Hercules? The Hercules' predecessors and its successor the Centaurus certainly made it into single engined aircraft. Considering how frequent Bristol motors were used in FAA aircraft, from the Flycatcher to the Skua and Albacore it's noteworthy that the Hercules never saw fleet service.
Twin engine fighters-bombers, like the Beaufighter would have made demands upon the Hercules similar to those of a single engine fighter. Though perhaps that's why the Beaufighter was considered for Merlin engines.
BMW 801 Diameter: 51 in (1,290 mm) Displacement: 2,560 in³ (41.8L)
R-2800 Diameter: 52.8 in (1,342 mm) Displacement: 2,804.5 in³ (45.96 L)
Hercules II Diameter: 55 in (1,397 mm) Displacement: 2,360 in³ (38.7 L)
R-2600 Diameter: 55 in (1,397 mm) Displacement: 2,604 in³ (42.7 L)
That is what I used to think until I saw a rotating cutaway engine at the Yorkshire Air Museum, the sleeves move side to side and up and down, so the sleeve and its support go well above the piston at TDC, it gives the illusion of the piston only going half way up the cylinder.It does seem odd that the Hercules is so wide, given that one of the advantages of sleeve valves is that you don't have the bulky poppet valve gear sitting on top of each cylinder. Other things being equal, the Herc should have been appreciably narrower.
It does seem odd that the Hercules is so wide, given that one of the advantages of sleeve valves is that you don't have the bulky poppet valve gear sitting on top of each cylinder. Other things being equal, the Herc should have been appreciably narrower.
Makes me wonder if Bristol would have been bettter off to skip the sleeves and instead develop a larger/powerful ohv Mercury or Taurus.That is what I used to think until I saw a rotating cutaway engine at the Yorkshire Air Museum, the sleeves move side to side and up and down, so the sleeve and its support go well above the piston at TDC, it gives the illusion of the piston only going half way up the cylinder.
But the better diameter comparison is between Bristol's ohv and their own sleeve. Perhaps Bristol engine were all uncompetitively wide, regardless of valve train.BMW 801 Diameter: 51 in (1,290 mm) Displacement: 2,560 in³ (41.8L)
R-2800 Diameter: 52.8 in (1,342 mm) Displacement: 2,804.5 in³ (45.96 L)
Hercules II Diameter: 55 in (1,397 mm) Displacement: 2,360 in³ (38.7 L)
R-2600 Diameter: 55 in (1,397 mm) Displacement: 2,604 in³ (42.7 L)
Makes me wonder if Bristol would have been bettter off to skip to she sleeves and instead develop a larger/powerful ohv Mercury or Taurus.
But the better diameter comparison is between Bristol's ohv and their own sleeve. Perhaps Bristol engine were all uncompetitively wide, regardless of valve train.
I suppose that's why the Blenheims were crated and shipped to Malaya rather than flown there, despite Britain having the necessary airfields. Here's the route, just ignore the stop in Lisbon needed to force the route to avoid Spain. Total 10,000 miles, at 198 mph cruise speed will require about fifty hours of flight time. Any reliable and well designed radial would handle fifty flight hours without needing a tear down at the final destination.Well, let's face it, folks. When the first PBY purchased by the British arrived in the U.K. a reporter attending the event said that it could not have flown very far because the nacelles were not covered with oil.
When the Short Sunderland Mk V came out the crews were delighted to find they could complete one of their long missions and come back with all four engines still running.
British radials often did not inspire confidence.
I suppose that's why the Blenheims were crated and shipped to Malaya rather than flown there, despite Britain having the necessary airfields. Here's the route, just ignore the stop in Lisbon needed to force the route to avoid Spain. Total 10,000 miles, at 198 mph cruise speed will require about fifty hours of flight time. Any reliable and well designed radial would handle fifty flight hours without needing a tear down at the final destination.
No British engine inspires confidence. I had a 1969 Triumph twin, and while over 11 years of I loved that bike, I could never trust it.
though western elites, indifferent to any sense of loyalty, have outsourced production to China.
If you read up on the failures of the British automobile and motorcycle industries you'll see a repeated claim that there were too many MBAs (sorry there) and business school graduates in upper management and not enough engineers. The Germans had the inverse experience, with their industrial giants being run by engineers. Perhaps that's part of the difference. I wonder if Bristol's engineers were hobbled by management directives on cost, resources or company direction.Britain went through some difficult times in its manufacturing industry in the 1970s, 80s and 90s. I went for an MBA a few decades ago (before they were as brain washy and PC as gender studies) and there I found that many of the quality control systems and manufacturing techniques were in fact developed and used by the British in WW2.
If you read up on the failures of the British automobile and motorcycle industries you'll see a repeated claim that there were too many MBAs (sorry there) and business school graduates in upper management and not enough engineers. The Germans had the inverse experience, with their industrial giants being run by engineers. Perhaps that's part of the difference. I wonder if Bristol's engineers were hobbled by management directives on cost, resources or company direction.
There's also the issue of The City, where much of British industry was run or beholden to financiers in London who didn't care about industry, just profits. At Honda, almost every dime of profit was reinvested into engineering, production, process and product improvements, while profits in Britain went almost entirely to divideds to the shareholders, resulting in WW2 equipment and methods languishing into the 1970s. Even today, the inverse to Britain in Italy can be seen in motorcycles. In Britain today Triumph motorcycles have moved all production to Thailand in order to chase profits for its City financeers, meanwhile in Italy, Moto Guzzi produces all its bikes domestically, because the company is owned by the very industrialists that supply the parts, rather than banks in Milan.