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Tuesday, November 26th 2013, 5:56pm

Fiat Scorpione Serie II and other Isotta-Fraschini diesel projects

I have intended to have the next step in the development of the Fiat Scorpione to include a re-engineering to the Isotta-Fraschini 2040cv diesel. These engines are currently used on the Macchi-Savoia-Marchetti Ermes and the Caproni Atlante. The Serie II would likely employ props like those of the Ermes, do the stats for the Serie II seem reasonable?

Fiat Scorpione Serie II
Crew: 4
Length: 24.38m Span: 36.27m Height: 6.02m Wing Area: 120m­^2
Empty Weight: 18,682kg Maximum Weight: 27,650kg
Engine: 4 x 2040hp Isotta-Fraschini diesel
Maximum Speed: 575km/h@4000m
Rate of climb: 350m/min
Service ceiling: 9,750m
Range: 5000km
Armament:Two twin remote controlled 13.2mm Breda-SAFAT gun turrets, one dorsal mount aft of the cockpit, one ventral mount aft of the bomb bay. Up to 4000kg of bombs.

Also, I stumbled onto this drawing of RA's for a Maritime recon version of the Caproni Astore that looks like it uses a pair of these engines.


I present the following as possible stats


Serie III
Year: 1945
Crew: 2
Engines: 2 * 2040hp Isotta-Fraschini diesel
Wing Span: 17.74m Length: 15.54m Height: 5.42m Wing Area: 45sq m
Empty Weight: 6688kg Max.Weight: 12400kg
Speed: 650km/h at 4000m Ceiling: 11000m
Range: 4000km
Armament: Recon gear and/or RADAR



Thoughts?
You smug-faced crowds with kindling eye
Who cheer when soldier lads march by,
Sneak home and pray you'll never know
The hell where youth and laughter go.
-Siegfried Sassoon

2

Tuesday, November 26th 2013, 6:23pm

Any reasonable long-range maritime reconnaissance aircraft of this period is going to have more than a crew of two. The plane needs to be piloted; it needs to be navigated; communications need to be maintained; and the electronic systems need to be operated. You can double up some of these things but given the technology of the time that will reduce the efficacy of the aircraft operation. I would say you need a minimum of four crew to accomplish the mission well. Of course, that merely my opinion - YMMV.

Diesel engines may be efficient, but I wonder if the airframe is capable of carrying sufficient fuel for the stated range? The Martin P4M Mercator, a far larger aircraft (albeit with different engines) was capable of little more than 4,000 km.

3

Tuesday, November 26th 2013, 6:47pm

Valid points. Few comments tho. I don't see the Serie III being used as a long range recon plane (that roll being filled by the big Fiat with its much greater endurance) but as a high speed one. The long range allows it to run a higher speeds for longer periods. I agree that more crewmen are needed, but think that radio/electronics could be merged into one position given the nature of the mission. Given that how does this look?

Serie III
Year: 1945
Crew: 3
Engines: 2 * 2040hp Isotta-Fraschini diesel
Wing Span: 17.74m Length: 15.54m Height: 5.42m Wing Area: 45sq m
Empty Weight: 6688kg Max.Weight: 12400kg
Speed: 650km/h at 4000m Ceiling: 11000m
Range: 3500km
Armament: Recon gear and/or RADAR

Note there could be a combat version of the same airframe (would be Serie IV) but I'm wondering about the ability of the diesels to take damage over that of the radials that the Serie I and II currently employ.
You smug-faced crowds with kindling eye
Who cheer when soldier lads march by,
Sneak home and pray you'll never know
The hell where youth and laughter go.
-Siegfried Sassoon

4

Tuesday, November 26th 2013, 6:50pm

Any reasonable long-range maritime reconnaissance aircraft of this period is going to have more than a crew of two. The plane needs to be piloted; it needs to be navigated; communications need to be maintained; and the electronic systems need to be operated. You can double up some of these things but given the technology of the time that will reduce the efficacy of the aircraft operation. I would say you need a minimum of four crew to accomplish the mission well. Of course, that merely my opinion - YMMV.

Diesel engines may be efficient, but I wonder if the airframe is capable of carrying sufficient fuel for the stated range? The Martin P4M Mercator, a far larger aircraft (albeit with different engines) was capable of little more than 4,000 km.

I think I agree with Bruce. Maybe everything is doable on those specs, but I'd wonder what sort of weird situation resulted in the requirement that led to those specs.

I could see this sort of plane being developed for shorter-range missions, for instance in the Med, where having a decent turn of speed might be handy to keep a step ahead of fighters. But that means the long range requirement, and the demand for diesels, is pretty much pointless in this role, at least as I see it. Whereas, if the demand for range is the driving requirement, having spare crewmen to help eliminate fatigue and spread out duties would be the dominating requirement.

On the flip side, I could see this plane with these sort of specs as a dedicated photo-reconnaissance aircraft; but Italy already has the Ermes for that role, and it's better.

5

Tuesday, November 26th 2013, 7:05pm

Valid points. Few comments tho. I don't see the Serie III being used as a long range recon plane (that roll being filled by the big Fiat with its much greater endurance) but as a high speed one. The long range allows it to run a higher speeds for longer periods. I agree that more crewmen are needed, but think that radio/electronics could be merged into one position given the nature of the mission. Given that how does this look?

Serie III
Year: 1945
Crew: 3
Engines: 2 * 2040hp Isotta-Fraschini diesel
Wing Span: 17.74m Length: 15.54m Height: 5.42m Wing Area: 45sq m
Empty Weight: 6688kg Max.Weight: 12400kg
Speed: 650km/h at 4000m Ceiling: 11000m
Range: 3500km
Armament: Recon gear and/or RADAR

Note there could be a combat version of the same airframe (would be Serie IV) but I'm wondering about the ability of the diesels to take damage over that of the radials that the Serie I and II currently employ.

Like most diesel engines, an aircraft diesel engine performs best when it operates at a constant RPM and power output - which makes it a great idea for a commercial transport but of questionable usefulness in a combat aircraft. Your speed value is - I presume - a max speed value; what is the aircraft's cruise speed? That is what will determine its range. I have doubts that operating a diesel engines at maximum power output would give it any better advantage at speed than a radial or inline piston engine.

With a three man crew you are assuming that the pilot flies the aircraft, the navigator navigates and serves as co-pilot while the third guy handles the radio, the electronics and everything else on the aircraft. All on very long flights. I have my doubts of this working in the long run. Certainly it could be done; the question is whether it can be done well.

6

Tuesday, November 26th 2013, 7:30pm

With both the Ermes and Scorpione, most of the long range recon duties are covered. What I imagined this plane working for (and what the airframe looks like it is suited for) is high speed recon. Italy already uses 165 Astores in recon rolls, and it is currently the fastest recon plane, but these are adaptations of bomber air frames and not made "custom" for the roll and I feel there are ways to improve how well the type preforms in the gap between tactical recon and leason aircraft such as the Caproni Ca.313 and the aforementioned big strategic recon planes. Currently, the engine in question is the most powerful in the Italian inventory that functions well at some measure of altitude, the Fiat A.38/2 being optimized for low-altitude work and the Alfa-Romeo 136 RC.40 is not as powerful (note this engine could work, but does not appear to match the drawing as a side-by-side comparison shows the engines are narrower then those for the current Alfa-Romeo 135 RC.40). I don't see much problem with upping the crew to four men, was just trying to keep weight down.
You smug-faced crowds with kindling eye
Who cheer when soldier lads march by,
Sneak home and pray you'll never know
The hell where youth and laughter go.
-Siegfried Sassoon

7

Wednesday, November 27th 2013, 12:33pm

If you want a fast tactical recon aircraft I would stick with the standard Scorpione and fit cameras in the bomb bay. For overland use a radar probably isn't necessary at this stage. There is no need to bother with diesels for tactical aircraft and indeed would probably hinder performance at some altitudes and power settings. A two-man crew would suffice but 3 probably best. I don't think Italy needs another maritime recon platform, and if you feel you do, the standard Scorpione or one with more powerful radials would be better for avoiding fighters over the Med, because high-altitude cruising is best done by the Ermes that cannot easily be intercepted (until jets arrive). For maritime duties 4 crew would be best. In either case the range is probably excessive with the diesels. I can see some logic behind the design but not enough to make it worthwhile.

8

Wednesday, November 27th 2013, 4:28pm

Ok, point well taken. Any comments on the Scorpione Serie II? That design seems to have evaded detection so far in the comments.
You smug-faced crowds with kindling eye
Who cheer when soldier lads march by,
Sneak home and pray you'll never know
The hell where youth and laughter go.
-Siegfried Sassoon

9

Wednesday, November 27th 2013, 5:23pm

Sorry for any confusion, my comments were referring to three-seat Astore tactical recon/ maritime recon variants as perhaps more ideal for Med use. The Scorpione just seems a little vulnerable stooging around the skies of the Med given the fighter defences in that region.

The Scorpione Serie II looks good, my only comment would be to raise the crew numbers to six/seven since four seems a little low given the complexity of this large aircraft. RA seemed to dislike large crews and felt he could get away with smaller numbers but realistically even the more electronically advanced RAF V-bombers of the 50s had five crewmen. The Scorpione probably needs a pilot, co-pilot, nav, radio op, flight engineer, radar op and perhaps a dedicated gunner/observer.

10

Wednesday, November 27th 2013, 6:03pm

Call it Five crew men.
You smug-faced crowds with kindling eye
Who cheer when soldier lads march by,
Sneak home and pray you'll never know
The hell where youth and laughter go.
-Siegfried Sassoon