The road to G-55 (with the special participation of the CS-38)

[Skybolt]

Planning for a new fighter built around the new 1250 HP in-line liquid cooled FIAT engine (tendered to the 1938-39 competition for new engines and designated A.38) started immediately. The job was trusted to the II Design Office (Gabrielli) in Turin. First result was a somewhat P-40-like design as far as the fuselage, using a wing with the same plan of the G-50. The A.38 evolved too, and influenced the design of successive version of the fighter project. First image (they are very low resolution, you'll understand... ) in the oldest version known, from July 1939. Back then the A.38 was a conventional V-engine with the compressor on the back and driving a conventional three-blade spinner. In 1940, the engine was redesigned as an inverted V, with the compressor positioned under the main block, thus shortening the power pack. The spinner became two contrarotating two-blade units. This version can be seen in second and third image. The wing remained the G-50 derived one. In fourth image, the final evolution (May 1941) of the A.38-powered G-55. The spinner is back to the three-blade single rotation type, and the wing follows the new planform that will be retained in the DB-powered version. As a comparison, I include in the fifth image a depiction of the CS-38, an alternative projected that was commissioned by FIAT management (they were used to pit one design office against another, they had four of them, two in Aeronautica d'Italia, one in CANSA in Novara and the final one in CMASA in Pisa). Ing. Manlio Stiavelli designed the CS-38 using as a reference the A.38 inverted V engine with the three-blade propellers. I think that this was from circa late 1940, early 1941.
I'll post the CS-38 data in a reply.

 

[red admiral]

The Fiat A.38 was a V16 engine not the normal V12 layout. This was inspired by the racing engine (AS.8) used on the CMASA CS.15 speed record plane.

Lots of details on the G.55 and big pictures can be found in Ali D'Italia 10

 

[flateric]

What a wonderful shapes! One of the most eye appealing designs of propeller-driven fighter I've ever seen

 

[Andrewjs2007]

Skybolt

Marvellous pics! I recognise one or two from the Ali d'Italia volume on the G.55, but the others are new to me.

Hope we can see larger/better quality copies in your forthcoming publication(s)?

Thanks again

Andrew

 

[Skybolt]

The G-55 A.38 early and late come from Ali d'Italia. The others has been already published, notably in Aerofan. The low resolution is to protect copyright of the publisher (who is mine, too, BTW, and a good friend). Since they are outside the scope of my editorial projects (too early and/or not the right companies.. ), the best way for anyone interested is to order the relevant Aerofan back issues ;D . It's number 64. A great issue, BTW.

 

[blackkite]

Hi! CMASA(FIAT) CS-38 fighter.
http://alternathistory.com/italyanskie-bumazhnye-proekty-proekt-odnomotornogo-istrebitelya-cmasa-fiat-cs38
http://translate.google.fr/translate?hl=fr&sl=ru&tl=en&u=http%3A%2F%2Falternathistory.com%2Fitalyanskie-bumazhnye-proekty-proekt-odnomotornogo-istrebitelya-cmasa-fiat-cs38&sandbox=1
Specifications CS 38 fighter (project)
Wingspan, m : 12.60, Length, m : 10.76, Wing area m2 : 24.00, Mass, kg : an empty plane : 2750, normal takeoff : 3800
Unit load on the wing, kg/m2 : 158.33, capacity kg/HP : 2.71,
Powerplant : engine type : 1 × FIAT a. RC 38.15-45, power, HP : Max takeoff : 1400, at an altitude of 4500 m : 1200,
Maximum speed, km/h : S.L. : 475, at an altitude of 4500 m : 565
The minimum speed, km/h : 130, Time to 6000 m : 9 ' 30 ", Range, km : at an altitude of 5000 m at a speed of 500 km/h :
1500, at an altitude of 5000 m at a speed of 400 km/h : 1700,
Flight duration (at a speed of 400 km/h) : 4:15, Crew, pers. : 1,
Armament : machine guns : 2 × 12.7 mm Breda-SAFAT MACHINE GUNS, Cannon : 2 × 20 mm Oerlikon,
Designer : Costruzioni Meccaniche Aeronautiche SA (CMASA), Marina di Pisa, Italy

 

[blackkite]

Hi! G.55 and variants.
Torpedo bomber had split radiators.

http://www.the-blueprints.com/blueprints/ww2planes/ww2italy/64073/view/fiat_g_55_centauro/
http://www.airwar.ru/enc/fww2/g55.html

https://www.youtube.com/watch?v=gmLok98-_3s

 

[iverson]

I've attached my drawing of the Fiat G.55 with the 1250-hp Fiat AS.38 RC-40, plus a drawing of the engine itself. The AS.38 was a 90-degree inverted V-16 composed, in essence, of two V-8 engines joined together, with accessory, supercharger, and cam-shaft drives taken from the middle of the engine, where the V-8s joined. This approach came from the Fiat Schneider Trophy V-24 race engine. It minimized torsional vibration from what would otherwise have been an overly long crankshaft. On the AS.38, the supercharger was mounted horizontally within the vee, which necessitated the 90-degree layout rather than the 45-degrees used with preceding Fiat V-16s.

 

[iverson]

For some reason, one JPG did not attach.

 

[blackkite]

Thanks!! Super drawings. Very interesting.

 

[iverson]

Thank you. I'm glad you liked them.

The side view was based on a factory drawing reproduced in Ali Antiche (I think) or possibly Aerofan. I worked out the other views using various three views of the DB605-powered G.55.

I have attached a front view showing my interpretation of the AS.38-powered version. This was the view that required the most experimentation, because the wide, 90-degree cyclinder heads changed the contours of the lower front fuselage significantly.

 

[iverson]

I looked up my source. It is "Fantasmi di Aerei et Motori Fiat dal 1935 al 1945 (prima parte)", by Giovanni Masino, Ali Antiche 106. I found it at http://www.avia-it.com/act/la_tecnica/la_tecnica_di_ieri/Tecnica_ieri_2015/Seg_art_ott_15/Fantasmi_di_aerei_e%20motori_Fiat_dal_1935_al_1945.pdf

 

[blackkite]

Amazing!! Thanks a lot again. Italian airplanes are very fascinating.

 

[airman]

Amazing!! Thanks a lot again. Italian airplanes are very fascinating.

Oh thank you !

 

[blackkite]

Hi! Fiat G-55 fighter with Fiat A.38 inverted V-16 contra rotating propeller engine and later single propeller A.38 engine.
(Skybolt-san said that "the oldest version known, from July 1939. Back then the A.38 was a conventional V-engine with the compressor on the back and driving a conventional three-blade spinner.In 1940, the engine was redesigned as an inverted V, with the compressor positioned under the main block, thus shortening the power pack. The spinner became two contrarotating two-blade units.")

https://oldmachinepress.com/category/aircraft-engines/

"The FIAT G.55 fighter was originally designed to use the A.38 engine with contra-rotating propellers (top), but the aircraft was redesigned once the switch to a single-rotation propeller (bottom) was made. Delays with the A.38 led to the Daimler-Benz DB 605 being installed in the G.55."

A.38 engine : V16, single propeller, compressor on the back(bottom drawing)⇒ Inverted V16, contra rotating propeller, compressor under the main block(middle picture and top top?) ⇒ Inverted V16, single propeller, compressor under　the main block(top drawing bottom) .