Ad: This forum contains affiliate links to products on Amazon and eBay. More information in Terms and rules
But would it be more troublesome than getting the licensed DB-601 into production? This could include avoiding the more extensive changes the Soviets made and remaining closer to the performance range the French managed with development of the 12Y (not 12Z) but possibly making further supercharger improvements or at least implementing 2-speed drive.
The question is why would you want to? the gun is heavy and slow firing and slightly less powerful than a Hispano round. Basically you get a rate of 2/3 that of a Hispano gun used in D. 520 83% of the ammo capacity for the same weight. Sticking a pair of them in a twin engine plane were the rear gunner could get to them to change magazines might have made a decent ground attack or light anti-shipping armament but a single gun in a single engine fighter is depending too much on the golden BB.Other than that, the Jumo 211 might have been easier to mass produce than the 601 (and the 211F would seem to line up with Ha-40/Ki-61 production) of course they wouldn't have been able to accommodate the Ho-3 in that case,
The Hispano engines seem better for a potential early/pre-war development as a direct follow-on for the earlier Ki-28 fighter design.
I was thinking less as a proper alternative to the DB-601 (let alone on an aircraft of the same size/weight as the Ki-61) and more as a smaller, lighter, at least moderately more powerful replacement for the Ha-9. Then again, perhaps that's something Kawasaki should have been working on back with the Ki-10 even before the Ki-28 rather than continuing development of the old BMW-derived V-12.The French performance range is only good enough to get the pilots killed. You are down 10-20% in power from the DB-601. lets look at the Hispano 12Y again. (and please remember that the Russians were not happy with the 12Y's over haul life/reliability back in 1934 when they got the license. Lets also assume the French ignore what was going on in china and the threat to their own SE Asia Colonies and are greedy enough to sell the Japanese the latest versions.
Couldn't indigenous Japanese supercharger development displace the older Hispano unit too? (aside from just potentially adapting it to 2-speed drive)Which runs right into another complication. HS had starting using superchargers designed by Szydlowski-Planiol which were much better than their own design.
Wiki lists the -33 as using a 5.8:1 CR. (the -36/37 is listed as 7:1)Best engine before the -51 using a HS supercharger was the -37 with 1050hp for take-off and 960hp at 1250 meters (8.33 supercharger gear) and 7:1 compression in the cylinders. The -33 had a 10.0 supercharger gear, 7:1 compression in the cylinders and offered 960hp for take-off and 955hp at 2250 meters. This require 100 octane fuel.
I was more just suggesting potential for what the IJA was already manufacturing. Getting the Ho-105 and Ho-5 into service sooner would have been far more useful. (adopting oerlikon FFF or FFL derived guns would probably be faster than the Browning derived 20 mm though) I suppose mounting larger numbers of 7.7 mm guns early-war would have been more effective too, but probably just better to replace those old, relatively slow firing Vickers derived LMGs as soon as possible. (of course the italians had a similar problem, but at least the IJA had a better replacement with the Ho 105 than the .50 Breda)The question is why would you want to? the gun is heavy and slow firing and slightly less powerful than a Hispano round. Basically you get a rate of 2/3 that of a Hispano gun used in D. 520 83% of the ammo capacity for the same weight. Sticking a pair of them in a twin engine plane were the rear gunner could get to them to change magazines might have made a decent ground attack or light anti-shipping armament but a single gun in a single engine fighter is depending too much on the golden BB.
I was thinking less as a proper alternative to the DB-601 (let alone on an aircraft of the same size/weight as the Ki-61) and more as a smaller, lighter, at least moderately more powerful replacement for the Ha-9.
Then again, perhaps that's something Kawasaki should have been working on back with the Ki-10 even before the Ki-28 rather than continuing development of the old BMW-derived V-12.
Unless I'm completely mistaken and the Ha-9 was actually making more power at altitude than the 12Y engines of the mid 1930s. (except even there, with the weight and drag savings on a fighter -and potential for engine mounted cannon, the 12Y still had plenty of advantages)
The Shiden was perhaps one of the best performing, yet least known, fighters of WWII.I suppose the better question would be: would an alternate N1K-2 like design (but with the earlier Kasei engine) also be adaptable as a carrier based fighter? (wing loading/stall speed, wheel pressure, and performance with tail-hook equipped and CoG shifts addressed would all come into play)
I had to dig around a bit but finally found this site again WarBirdsSmaller may be correct, lighter may be debatable (at least from a practical standpoint). Moderately more powerful may also be debatable. There is not much information on the Ha-9 engine. we know the parent BMW engine went around 510KG which isn't that far off from the the later 12Y's. Now it is quite possible the Ha-9 porked up a bit over the base BMW but a 40-60kg difference isn't that much to get exited about.
The Ha-9IIb as used in the Ki-32 was listed at 850hp for take-off, 775hp at sea level and 950hp at 3,800 meters( 12,470ft) by Rene Francillon in "Japanese Aircraft of the Pacific War"
The Ha-9IIa as used in the Ki-10 and Ki-28 was listed at 850hp for take-off, 720hp at sea level and 800hp at 3,500 meters( 12,485ft) same source.
It seems like adopting the 12Y back in the early 1930s in place of continued BMW VI/IX development might have been better for the likes of the Ki-10 and Ki-28. Then again, it seems like Kawasaki got a fair bit out of the old BMW design as it was. (compared to Mikulin taking the same bore/stroke/displacement and asymmetrical stroke piston with articulated connecting rod arrangement with the cast-block AM34 and ran with that instead -the Ha 9 seems to have managed pretty decent power and altitude performance -if these figures are accurate- while keeping weight much lower than the Mikulin designs)Advantages seem small depending on which model 12Y, plus you have the cost/trouble of setting up production for an engine with a rather limited future. You can trace the 12Y back through the 12N and then to the 12Lb of 1927. It had already seen quite a bit of development. There was a reason the Allison and Merlin and Jumo 211 and DB 601 weighed several hundred pounds more than a 12Y. The 12Y wasn't strong enough to stand up to making much more power than it was. Both the crankshaft and crankcase were too light.
The J2M seems nowhere remotely close to making sense as a carrier based fighter and would be competing with similar engines as the N1K (with both Kasei and Homare being useful on the N1K) so even if the N1K sticks to land only, making more of those over some J2Ms seems a lot more sensible. (a simplified J2M might get into service sooner than any N1K derivative though, but the short range makes it mostly useful for interceptor defense work and possibly close support)So keeping the N1K-J land-based and perhaps try to find a way to ramp-up the J2M for carrier ops and stay with those two as they were top-performers.
But herein lies the problem:The J2M seems nowhere remotely close to making sense as a carrier based fighter and would be competing with similar engines as the N1K (with both Kasei and Homare being useful on the N1K) so even if the N1K sticks to land only, making more of those over some J2Ms seems a lot more sensible. (a simplified J2M might get into service sooner than any N1K derivative though, but the short range makes it mostly useful for interceptor defense work and possibly close support)
An upgraded/refined A6M with greater emphasis on armament, engine power (ie Kinsei) structural strength, and armor/protection by 1940/41 would be important. A Zuisei powered A5M derivative might work better earlier. Given its earlier availability, having the A6M target the Kinsei from the start would make more sense too.
Yes, after thinking on it more (and as I shifted towards in the conclusion of my previous post), what Kawasaki managed with the Ha 9 was probably good enough to not merit bothering with the HS engine. (licensing and developing that older design may have been more cost effective for them too, and easier to adapt to the mid 1930s Japanese engine manufacturing industry)Without a total redesign it had reached it's limit/s. If the Japanese had gotten a licence in 1933/34 like the Russians did and spent a large sum of money tooling up for mass production (really massive like the Russians) then maybe sticking with it and trying to upgrade it make sense. Buying it in 1938-39 is an act of pure desperation as several engines, if not actually on the open market, have shown how out of date the Hispano-Suiza is.
Indeed, several engines did similarly (the 'C' series R-2800 shares relatively little other than bore/stroke and external dimensions the the earlier models). Really, it's not that unlike the transition the Russians made going from the M17 to AM34. (similar bore/stroke/displacement and assymetric cylinder configuration, but a totally new engine)Wright took the R-1820 Cyclone from 575hp to 1525hp over around 20 years but at several times threw out everything but the bore and stroke. Changing to forged steel crankcases from Aluminium meant new foundry equipment. (and there were at least 3 different steel crankcases) changing the way the cylinder fins were made required a massive investment in new tooling, Cylinder heads changed from cast to forged and so on.
Yes, and in that context I still think the Jumo 211 would be the more interesting alternative to consider.Japanese went withe DB-601 in an attempt to get a "modern" engine pretty much 'of the box' and and not a collection of parts that needed extensive modification and substitution to bring it up even close to modern standards.
Of those, the Ki 28 seems the most worth the upgrade, but if the modifications were too extensive, it may have been better to just focus on a new design entirely, but stemming from the same emphasis on speed and streamlining. (granted, raw engine power seems to have been an interest too, and certainly an area the Ki 28 had an edge over the Ki 27 and Ki 33 or A5M) Retractable or semi-retractable gear combined with the existing Ha 9 (or another Ha 9 model) might be useful if implemented early enough.A Zuisei powered A5M sounds neat but hte Japanese had a real shortage of engineers, the more time spent on updating really obsolete designs like the A5M and K-27 (or Ki 28) is less time they could have used to build more modern/useful planes.
Not to mention planes where average or exceptional pilots could have a better chance of surviving being shot down (be it bailing out or crash landing -or limping home with extensive damage), especially significant over friendly territory where returning to combat duty would be rather straightforward, or near enough to the front lines of having a chance of evading capture. (even with the ... issues with Imperial Japanese doctrine and sense of honor, there's still a big difference between living to fight another day and living to be captured by the enemy)The Japanese were 1-2 years behind the west as it was. Think Zero or Ki-43 over the English channel in the Spring/summer of 1942. They, like the Germans, needed planes the 'average' pilot could use to effect. Not planes that needed great skill (even if they rewarded that skill) to get kills with.
Using the bulkier Kasei should still make reasonable sense too, with later introduction of the Homare and limited production and availability all around. Performance would be somewhat reduced earlier in the war with earlier engine variants, but so would the opponents.Dave - the J2M was not navalized, though it was ordered and used by the Navy. The Shinden ('normal' one, not the pusher) with the wing relocated down ASAP should be indeed a fine fighter, but the Homare of 1944 was not the Homare of 1945?
Again, the Jumo 211 seems an interesting option, and would you at least agree that production of that engine likely would have gone more smoothly than the DB designs?Agreed with SR6 re. Hispano engine - once the DB 601A/Aa is available for the Japanese, the 12Y lost most if all of it's appeal. The Ki-61/DB 605A should be another fine fighter, BTW.
Ahh Tomo, yes, you're correct...I messed my post up because the ipad hates this server.Dave - the J2M was not navalized, though it was ordered and used by the Navy. The Shinden ('normal' one, not the pusher) with the wing relocated down ASAP should be indeed a fine fighter, but the Homare of 1944 was not the Homare of 1945?
Agreed with SR6 re. Hispano engine - once the DB 601A/Aa is available for the Japanese, the 12Y lost most if all of it's appeal. The Ki-61/DB 605A should be another fine fighter, BTW.
With the existing J2M and N1K, it really seems like the latter is far closer to being a practical carrier borne fighter (and the superior land based fighter) while also likely performing better on the whole even if using the same engine. (if not quite as fast, at least having better range and handling)The intention was to say that the J2M was in development longer and could have been navalized during that time.
The first flight by the J2M was in spring of 1942, making it a possible candidate to replace the A6M as the Raiden was a superior performer despite it's shorter range.
It's hardly surprising that Harris wanted to ditch the Halifax and shoot Handley Page
Way back I said the Halifax should have been cancelled at the earliest opportunity and have just stumbled across some interesting statistics compiled in a report entitled 'Comparison of Aircraft Types'.
Aircraft. Casualty Rate. Bomb Load/Sortie. Bombs Dropped/Missing Aircraft. 'Cost'
Lancaster 3.5% 3.95 tons 112.6 tons 20 man months/ton bombs dropped
Halifax 5.4% 2.20 tons 45.4 tons 60 man months/ton bombs dropped
Mosquito 2.3% 0.68 tons 29.8 tons 20 man months/ton bombs dropped.
Based on all operational sorties from 1st June to 15th September 1943 and a Mosquito bomb load of 4,000lbs.
It's hardly surprising that Harris wanted to ditch the Halifax and shoot Handley Page
Cheers
Steve
That is only revealed by statistics, many crews liked the Halifax as it was obviously easier to get out of, they weren't immediately aware how much more likely they would need to.
The RAE looked at self sealing fuel tanks for the Lancaster, but the 1000lb weight penalty was deemed too great. It also investigated sub-dividing the large wing root tanks on the Lancaster but I haven't been able to find out if this ever happened.
The RAE looked at self sealing fuel tanks for the Lancaster, but the 1000lb weight penalty was deemed too great. It also investigated sub-dividing the large wing root tanks on the Lancaster but I haven't been able to find out if this ever happened.
The B-26 was the first U.S. combat aircraft to have self sealing tanks as a standard feature (1936 - called "Merang cells")Did B-17's and B-24's have self-sealing fuel tanks?
What about the medium bombers?