The "Famous Concorso", Italy, 1946

In late 1946 the shape of the Italian aeronautical industry was rather dire. According to the Armistice agreement, every new construction was forbidden (modifications and completion of already started airframes was exhempted, and this allow for the "new" G-212s and SM-95s, the modified bombers of the Corrieri Militari, etc). It was expected that ban would have been lifted sometime in 1947, so there was some design and even construction activity (the MB-308, for one, was started well before the lifting of the ban). Anyway, incertitude was great and trust in the Government at an all time low. In this timeframe, it fell like a bolt the news that Ministero dell'Aeronautica RFPed a new construction aircraft to be destined to the night and low visibility flight training, light transport, radiometering and liason roles. the specs were rather "free", except for the engines, that were to be tassatively two Isotta Fraschini Delta III series, a great numbers of which (and spare parts) were in storage from wartime. All the still active aeronautical companies were invited to tender.
Not alla of them responded with designs strictly in adherence to the specs, judging (correctly) that 1600 HPs (two Deltas III) were too low a power for a transport aircraft. Anyway, these were the submission (the * were not to spec):

Caproni Ca-191
Santangelo Orsa
SIAI Marchetti SM-104
Breda-Pittoni BP-471
Macchi MB-312
Piaggio P-135*
SIAI Marchetti SM-105 (first version, non detachable fuselage)*
FIAT G-218*
All sumbission were in by late spring 1947 and winenrs were announced in summer.
The winners were Caproni Ca-191 and the outsider Orsa (Santangelo was a designer working for the Direzione Generale Costruzioni of the Ministero and wasn't new to "answering" the specs he had contributed to draft...). Orsa was to have been built by CAB (Caproni Aeronautica Bergamasca). Orsa wasn't even started, but Ca-191 was built in mock-up form in an emptied Caproni Taliedo (in a really dark atmosphere, with Communist terrorists killing technical and managerial figures linked with the airplane and mechanical industry).
How the Concorso ended ? In musical terms, it was a case of "diminuendo al niente". In January 1948 Santangelo himself wrote an editorial rethorically asking what had happened of the Concorso (if "he" didn't know, who else ?). Breda decided to proceed all the same and, after modifying the original project for use with two more powerful engines, built and flew te BP-471. Caproni abandoned the Ca-191 and concentrated all resources left on the Ca-193 aerotaxi. SIAI abandoned the SM-194 and heavily modified (actually, it was a new design) the 105 transorming it in a detachable pod transport. The others simply faded away. And now, the individual aircrafts.

Let's start with the least knowns. First, Piaggio P-135. Chief designer: Giovanni Casiraghi. It was of all-metallic construction (Piaggio was one of the few Itaian companies able to do that). DImensions: span 22.0 mts, lenght 16.75 mts, height 6.67 mts. Engines: two Wright Cyclones 704-C9-GC (1014 HP at 2200 mts). Max. speed: 370 KM7h at 4900 mts. Weight: void in transport version 5350 kgs. MTWO 11.000 kgs. Range with 3500 kgs of payload at 4500 mts and 320 Km/h: 1100 kms.
Note the Casiraghi's typical negative-sweep trailing edge.

Skybolt said:

Let's start with the least knowns. First, Piaggio P-135. Chief designer: Giuseppe Casiraghi. It was of all-metallic construction (Piaggio was one of the few Itaian companies able to do that). DImensions: span 22.0 mts, lenght 16.75 mts, height 6.67 mts. Engines: two Wright Cyclones 704-C9-GC (1014 HP at 2200 mts). Max. speed: 370 KM7h at 4900 mts. Weight: void in transport version 5350 kgs. MTWO 11.000 kgs. Range with 3500 kgs of payload at 4500 mts and 320 Km/h: 1100 kms.
Note the Casiraghi's typical negative-sweep trailing edge.

Click to expand...

Interesting and unseen, anyway it seems to resemble the Breda-Pittoni or it is only a mine impression??

Incredible my dear Skybolt,

thank you very much,and if you have any info about MB.312.

Peppe, the only similarity is in the profile of the nose. The wing, for one, was completely dfferent, as it will become clear when I'll post the BP (just an anticipation: the Breda used a gull-wing, derived from the wing used in the divebomber Ba-201).

Hi skybolt,

do you have more about the Macchi? Thanks!

Servus Maveric

Mav, I'm currently in idle following the packing-up of my books and part of docs. Of the Macchi I have a side view published in Ali Italiane in 1947.

Hi
Are there any drawings of the Breda BP-471??

Uh, that's easy.

And since it's easy, I'll spurn the so trivial Twin Wasp version (the one that flew) and with a degree of "sprezzatura" I'll offer the rarely seen original version with the intended I.F. Delta IIIs. Enjoy.

Hi Skybolt,

can you post the side view of the Macchi MB.312 (some technical data), please.

Thanks Maveric

Hi Skybolt
Thank for the Breda drawing, do you have more abouth the history of this design?
I will make, I dont know when, a drawing with the P and W engines.
Jan

Not much on the history of the design. Breda archives were utterly destroyed when Breda Aviazione went bankrupt in 1950, with a degree of prejudice that appalled the witnesses. The wing plan and structure is taken directly form the wartime Ba-201 (a dive bomber, later called Ba-210), that was aerodynamically studied by Mario Pittoni, then in charge of the subsonic wing tunnel at Breda, and who designed the 471 (the "P" in BP). The Breda chief designer in 1947-48 was Zappata, but he was totally occupied in completing and flying the 308. Pittoni wrote in the technical report that the choice of the gullwing was motivated by sound practical reasons (diameter of the spinners, length of the main landing gear), but in reality the only motivation was design speed, since the aerodynamical studies were already completed and structuraly it was only a scale up. The gull wing nevertheless gave the design excellent manouvrability and directional stability. The Concorso rules asked for an airplane that could be used for different purposes: transport, navigation training, instrumental flight training. Breda choose to suit the different roles with slightly different versions (different layouts of the nose and lateral accesses), and this was probably the motivation of the design not being chosen.
Mario Pittoni was highly skeptical on the viability of the Delta III engine for propelling an airplane of this size, and from the beginning designed version with more powerful radials. The Twin Wasp was in the end chosen for its easy availability and low cost.
Like other builders, Breda was in the end dismayed in discovering that the Concorso was no more than a design exercise and that there were no possibilities (and money) for funding prototype construction. Deciding to go ahead and build the BP-471 on own funds was probably the last straw that killed Breda Aviazione.

Thanks
Jan

Hi,

the Breda BP.471.

Thanks Hesham

Taadaaaa, I found (listen, people) the complete three views of the Macchi MB-312. Not even the authors of the recent book on Bazzocchi ("Never give up") have it.... Now, a little suspence, I promised my friend Giorgio Apostolo to let him see it first. You'll have to wait Friday this week.

Skybolt said:

Taadaaaa, I found (listen, people) the complete three views of the Macchi MB-312. Not even the authors of the recent book on Bazzocchi ("Never give up") have it.... Now, a little suspence, I promised my friend Giorgio Apostolo to let him see it first. You'll have to wait Friday this week.

Click to expand...

Can't wait, can't breathe......

Now, breathe...

Skybolt said:

Let's start with the least knowns. First, Piaggio P-135. Chief designer: Giovanni Casiraghi. It was of all-metallic construction (Piaggio was one of the few Itaian companies able to do that). DImensions: span 22.0 mts, lenght 16.75 mts, height 6.67 mts. Engines: two Wright Cyclones 704-C9-GC (1014 HP at 2200 mts). Max. speed: 370 KM7h at 4900 mts. Weight: void in transport version 5350 kgs. MTWO 11.000 kgs. Range with 3500 kgs of payload at 4500 mts and 320 Km/h: 1100 kms.
Note the Casiraghi's typical negative-sweep trailing edge.

Click to expand...

My contribution to this topic. It's an early work to be revised, but could give an idea of the subject.
Cheers