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Now that you mention it, that does appear to be a different aircraft.I believe this a version ( model?) of the SM.86 and not the SM.88. The SM.86 was a development of the SM.85.
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Small wing and two 460hp 9 cylinder radials.
There were two SM.86 aircraft, one with a pointer nose and a pair of 600 hp Walter Sagitta inverted V-12 engines
and a second one with 540 hp Isotta Fraschini Gamma inverted V-12 engines.
The 2nd one may have had twin tails and more revisions to the cockpit/canopy.
These were all small aircraft with a single fuselage.
The SM.88 was somewhat larger and used two booms and a center fuselage (a bit bigger than a P-38).
A stepping stone to the SM.91
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Problem with all of them is the lack of suitable engine produced in Italy and the lack of German supplied engines.
Why the Delta when we have the theoretical developed Asso engine? The Delta at the time topped out at around 750 hp, when the developed Asso would reach ~1,000 hp with similar weight and dimensions.Now that you mention it, that does appear to be a different aircraft.
The SM.86 had a lot of potential, but it needed a few changes. First, it needed Isotta-Fraschini Delta engines that would've given it more power and speed (while also not requiring too big of changes). Then, give it a rear gunner and it would've been a good dive bomber.
I actually was not aware of that engine having the same dimensions! If that's the case, then that would be a good design as well.Why the Delta when we have the theoretical developed Asso engine? The Delta at the time topped out at around 750 hp, when the developed Asso would reach ~1,000 hp with similar weight and dimensions.
The dimensions may have been similar, the weights were not. The V-12 Asso was about 80kg heavier except........................the Delta was air cooled and did not require a radiator and coolant. Around 140-150kg for 1000hp engine?Why the Delta when we have the theoretical developed Asso engine? The Delta at the time topped out at around 750 hp, when the developed Asso would reach ~1,000 hp with similar weight and dimensions.
Development of the Delta was probably (certainly?) the direct consequence of the Italian Air Ministry urge to have the engine companies make a switch to the air-cooled engines. The 'air cooled switch' was an self-inflicted wound, forcing the companies making the liquid cooled engines to abandon a lot of the institutional knowledge about these engines, and start anew.Why the Delta when we have the theoretical developed Asso engine? The Delta at the time topped out at around 750 hp, when the developed Asso would reach ~1,000 hp with similar weight and dimensions.
I'd agree with you if this was a single-engined aircraft, but the CR.25 has more than enough space and heft to handle that extra weight.The dimensions may have been similar, the weights were not. The V-12 Asso was about 80kg heavier except........................the Delta was air cooled and did not require a radiator and coolant. Around 140-150kg for 1000hp engine?
And you don't use the propellers from 600hp engines on 1000hp engines. (or even 750hp engines although that change isn't as great)
Now the real problem is that the two original engines (the 600hp Walter and the 540 hp Isotta Fraschini Gamma engines) were both around 380kg each.
The Delta was in the 510kg area and the V-12 Asso was about 594 without the radiator and coolant.
It might have possible but it was going to take a lot of work.
The CR.25 probably could have been modified to take the Asso L.121/L.122, but then the CR.25 was equipped with 840hp 570kg Fiat A74 14 cylinder radials.I'd agree with you if this was a single-engined aircraft, but the CR.25 has more than enough space and heft to handle that extra weight.
And having to rework the design to deal with the Asso L.121/L.122 is a hell of a lot better than having to deal with the absolute nightmare that is the Ba.88.
I didn't know about this forced switch, interesting. I feel like the switch from further developing Asso to working on the Xeta was a mistake, especially given the lack of knowledge of liquid cooling when I-F was making an inherently difficult to work engine design. The Asso was doing pretty good already. I think they could've stayed with that. Another option would be to get Reggianes Re 1Development of the Delta was probably (certainly?) the direct consequence of the Italian Air Ministry urge to have the engine companies make a switch to the air-cooled engines. The 'air cooled switch' was an self-inflicted wound, forcing the companies making the liquid cooled engines to abandon a lot of the institutional knowledge about these engines, and start anew.
We can just imagine the time and money lost at RR have they been forced to abandon their liquid-cooled engines and start making air-cooled types, especially if these are radials. Or, forcing the P&W or Wright to switch from the radials to the liquid-cooled V12.
About the Asso - I-F made the L.121 spin-off (900 HP @ 4km) and L.122 (1000 HP @ 4 km) before 1940. The best Deltas were supposed to do 840 HP at altitude, and by mid-war; I'm not sure these actually powered an in-service aircraft.
I'll be 100% honest, I completely forgot we were talking about the SM.86. My bad!The CR.25 probably could have been modified to take the Asso L.121/L.122, but then the CR.25 was equipped with 840hp 570kg Fiat A74 14 cylinder radials.
Not the 380kg kg engines that the SM.86 was using.
CR.25 was about 33% heavier than the SM.86 empty so there was a lot more room/stretch to add/modify things.
It was discussed earlier in the topic, but Reggiane's engines are generally off the table. Reggiane as a company was hanging by threads for a majority of the 30's and would likely be unable to produce a satisfactory amount of engines. Now given that they often worked with Piaggio gives us an interesting opportunity. Theoretically Piaggio could have mass-produced the Re 101 instead of some of their horrid radial engines and then we'd be getting somewhere. But the Re 103 and beyond were way too late to make a tangible difference.I didn't know about this forced switch, interesting. I feel like the switch from further developing Asso to working on the Xeta was a mistake, especially given the lack of knowledge of liquid cooling when I-F was making an inherently difficult to work engine design. The Asso was doing pretty good already. I think they could've stayed with that. Another option would be to get Reggianes Re 1engines in service since they were generally equivalent to other inline engines in power.
Yes, as I mentioned back in post #6 of this thread, the Italian aviation industry spread it efforts too wide. Fixing the Italian Military, 1933~1945 , and the industry was very sub-optimally organized for political reasons.It was discussed earlier in the topic, but Reggiane's engines are generally off the table. Reggiane as a company was hanging by threads for a majority of the 30's and would likely be unable to produce a satisfactory amount of engines. Now given that they often worked with Piaggio gives us an interesting opportunity. Theoretically Piaggio could have mass-produced the Re 101 instead of some of their horrid radial engines and then we'd be getting somewhere. But the Re 103 and beyond were way too late to make a tangible difference.
Generally it would probably be best if Reggiane stuck to building aircraft, especially since the Re.2000 would have the inline engine (theoretical Asso) it was supposed to have from the get-go.
Theoretically Piaggio could have mass-produced the Re 101 instead of some of their horrid radial engines and then we'd be getting somewhere.
Sure, of the three manufacturers Piaggio made the "best" radials. But on the other hand, that's a bar so low you could trip over it.I'd say that out of the three Italian companies making the radials of military importance - Fiat, Alfa Romeo, Piaggio - the later made probably the best radialsFiat's main engine (A.74) was of low power, the 1-row Fiat and A.R. engines were badly behind the curve, and the 18 cylinders of both Fiat and A.R. were a show and tell of not how to make 18 cylinder engines.
The Italian industrial base was much smaller than the Japanese industrial base and some of the key questions are..........Sure, of the three manufacturers Piaggio made the "best" radials. But on the other hand, that's a bar so low you could trip over it.
I believe someone somewhere mentioned the possibility of an Italian manufacturer license-producing a Japanese radial? Say, Alfa Romeo mass producing the Ha 5 or Kinsei families as they wouldn't be license-producing the DB 601 with the advent of the improved Asso? IMO that would be a better use of resources than any of the Italian radial projects.
I looked it up, and Wikipedia claims that the CR.25 was considered for bigger wings and DB 601s in 1943. If this is real, then that idea being moved back to 1940/41 would be a good plan IMO.I'll be 100% honest, I completely forgot we were talking about the SM.86. My bad!
But regardless, the SM.86 might not even be needed with a properly developed CR.25 - from what I understand the scramble for twin-engined aircraft was due to the Breda 88's failure. If the CR.25 was properly developed, it could almost certainly fill the dive bomber / strike aircraft niche the SM.85 and SM.86 were designed for.
As noted by SR6 above, Japanese radials are too late for the Italian needs. They need the competitive engines in 1940-42.I believe someone somewhere mentioned the possibility of an Italian manufacturer license-producing a Japanese radial? Say, Alfa Romeo mass producing the Ha 5 or Kinsei families as they wouldn't be license-producing the DB 601 with the advent of the improved Asso? IMO that would be a better use of resources than any of the Italian radial projects.
You may be right. But it was going to take lot to turn the I-F into a first rate engine.I will always agree with the notion that I-F best keep making and developing the liquid cooled V12s
I have no dreams about the Asso being a 1st rate engine. What it might've been is the 'Italian M-105', once the 2-speed S/C is installed on the L.122.You may be right. But it was going to take lot to turn the I-F into a first rate engine.
True but that is problem when you take a 1920s engine and put a reduction gear on the front and supercharger on the back and keep all the old stuff inbetween.My plan B for I-F to make 1st rate engine is pretty boring - make the DB engines under licence. The suggestions you've listed are all good, however the engine made after that list is basically a brand-new type.
OK 2nd rate engineI have no dreams about the Asso being a 1st rate engine.
You have a 32.65 liter engine turning at 2350rpm (at best?) and the DB 601 is 33.9 and turning 2400rpm and 2500rpm for take-off.Still the far cry vs. what I-F were making after ~1938, and same vs. the Fiat A.74. Possibly the combination of bigger valve overlap allowed by the direct fuel injection + a more refined S/C might've added another 15% to the power?