Bugatti 110P Fighter

[Jemiba]

Perhaps under the pilot to the gear in front ? With a shaft bent via a kardan joint ?

[elmayerle]

Just a thought, the drawing posted by jeniba shows jointed drive shafts from the twin engines passing either side of the cockpit.
If, as in flitzer's reconstruction, it was re-engined with a single engine, where would the driveshaft go? A straight shaft would go through the middle of the cockpit (and the pilot).

    robin.

I'd modify the engine gearbox to drop the shaft as low as possible and see if I could run it under the pilot to the gearbox and prop control at the front, done right, it wouldn't be that much different from what's on the P-39/P-63.

[smurf]

This might affect choice of engine - one with drive shaft set low re cylinders?

[elmayerle]

The location of the output driveshaft relative to the engine is amenable to change by changing the gearbox on the engine itself.  I daresay the drivehsaft exiting the engine on the Allisons in the P-39 and/or P-63 did not have the same relationship with the engine centerline that the propshaft on Allison versions for the P-38 did.

[smurf]

Thanks for that.  Easier than changing the engine, though their might still be some benefit in that? Clearly a radial would need more "offset" than an inverted V in-line.

[elmayerle]

Personally, I'd not try an aircooled engine in that closely packed installation, not unless I had some very good forced cooling flow, or some very carefully located scoops to direct extra cooling air (the problem occurs today if you're not careful in designing the cooling for Lycoming's IO-720 flat-eight aircooled engine; the last pair of cylinders really needs an extra source of cooling air.

[smurf]

Agree entirely.  I wasn't suggesting using a radial, just thinking that the less 'out-of-line' the shaft, the smaller any weight to compensate, a radial being the worst case. And I should have said a V, with the shaft low, not an inverted V.  How to cause confusion!

[snurg]

Just a thought, the drawing posted by jeniba shows jointed drive shafts from the twin engines passing either side of the cockpit.
If, as in flitzer's reconstruction, it was re-engined with a single engine, where would the driveshaft go? A straight shaft would go through the middle of the cockpit (and the pilot).

    robin.

I can think of at least two ways:  one is to use a gearbox to offset the shaft to the left or right, and run it alongside the pilot, or use a gearbox to split the engine's output between two shafts, routed as on the original.

It was a really gorgeous design, but if I were a fighter pilot, I think I'd want to see behind me a trifle better...

[Jemiba]

".. a gearbox to split the engine's output between two shafts, routed as on the original.2

Not a bad idea, I think, as this would alllow the use of a contra prop with a simple and light
gear in the nose. And with this relatively light design reducing the torque effects probably
would be quite useful during take-off and landing (remember the experiences with the later
marks of the Spitfire compared to the Seafire FR.47 with contraprops )

[Justo Miranda]

Bugatti fighter


I have been working on the scale drawings of the T67 V16 engine as published in http://www.bugattiaircraft.com with the intention of rebuilding the look that the mythical Bugatti 110P could have had.
As per my estimations the installation of the T67 in the fuselage of a standard 100P requires the following modifications:

-   The undercarriage wide track must be increased from 2960 to 3300 mm
-   Wingspan must increase from 8235 up to 8684 mm
-   Tailplane span must increase from 1410 to 1459 mm
-   Overall length must be augmented from 7700 to 8333 mm
-   Height should increase from 2122 up to 2188 mm
-   Propeller disc diameter must increase from 1698 to 1896 mm.
-   Vertical fin must increase from 994 up to 1038 mm length

The mod. 110P would have been an air superiority fighter equivalent to the Dewoitine D.520 T.
In my opinion it should have been armed with six MAC 34 A machine guns of 7.5 mm in the wings (similar installation to the D.520T) and a Hispano Suiza H.S. 404 gun of 20 mm with the ammunition stored in drums of 60 cartridges that the pilot could replace manually.

Given the decentralising policy of aeronautical production started by the French government in the last years of the decade of the thirties, it seems reasonable to assume that the Bugatti military version would have been propelled by an engine of the same firm and not by a Hispano Suiza HSY 45 which production had been kept for the Dewoitine D520 and Arsenal VG33.

I believe that the 110P would have a unique power shaft in central position located under the pilot seat http://www.secretprojects.co.uk/forum/index.php/topic.1100.45.html
It should also have a flat windscreen to avoid the optical distortion when using the OPL RX39 gunsight http://www.secretprojects.co.uk/forum/index.php/topic.1100.0/highlight.bugatti.html

Based on all these assumptions I will try to reconstruct the internal look that the 110P might have had and, if the whole thing looks convincing, I will also try to draw the external look.

[Pepe Rezende]

At my opinion, the fighter version would have a conventional cockpit, one 20mm shaft gun and two 7.5mm machine guns with contrarotating propellers.

Cheers

Pepe

[Justo Miranda]

It is a physical impossibility to install a French cannon of 20 mm in a Bugatti 100P.
The Hispano Suiza H.S.7 measures 2100 mm long, the H.S.9, 2070 mm and the H.S. 404 measures 2500.
The distance between the propeller gearbox and the pilot seat back is just 1500 mm. The only solution is to install the seat more to the rear, in the position of the forward engine.
It is an argument in favor of a bigger airplane with a single engine. The field maintenance difficulties that a two engined airplane would have, must also be taken into consideration.
The unfortunate operational experience of the French squadrons equipped with Caudron 714 fighters in 1940 show us how difficult is to convert a racer into a warrior.
As for the flat windshield, it is just a must for the pilot fighters. It is a physical law.

Cheers,
Justo

[Pepe Rezende]

It is a physical impossibility to install a French cannon of 20 mm in a Bugatti 100P.
The Hispano Suiza H.S.7 measures 2100 mm long, the H.S.9, 2070 mm and the H.S. 404 measures 2500.
The distance between the propeller gearbox and the pilot seat back is just 1500 mm. The only solution is to install the seat more to the rear, in the position of the forward engine.
It is an argument in favor of a bigger airplane with a single engine. The field maintenance difficulties that a two engined airplane would have, must also be taken into consideration.
The unfortunate operational experience of the French squadrons equipped with Caudron 714 fighters in 1940 show us how difficult is to convert a racer into a warrior.
As for the flat windshield, it is just a must for the pilot fighters. It is a physical law.

Cheers,
Justo

When I said a conventional cockpit I thought about a raised cockpit and a raised seat. Six wing guns seems excessive to me. Four guns could be more probable. The Caudron just needed a better engine. Equipped with an Isotta Fraschini engine showed a very nice performance.

Cheers

Pepe

[J.J.Horst]

I just saw your efforts on the 110P, which of course remains a mistery, as it never came even close to a final design.

The only thing we in the BAA have, is a sketch by Ettore Bugatti, of a variant with two T50B 8-cylinder engines side by side, and a cannon in the nose. Of course the 110P will have to be slightly larger than the racer plane 100P, to make it a useable airplane. I will posty more on this forum in future.

For now, I have a question; Does anybody have photographs of the Hispano Suiza 12Z engine? There is a reported Bugatti car, with a 12 cylindre 4-valve engine of about 30 litres, and I try to find out what engine it has. The 12Z seems a possibility, but I don't have reference photogrpahs for that engine.

[Justo Miranda]

The attached drawings represent a possible solution for the 110P with a Bugatti T67 engine.
Such an engine could not be used in the 100P model but only in a slightly bigger plane.
The installation of the armament also requires some changes to the pilot position as well as an increase of the wingspan.

On the contrary, using the HS 12Z engine, much narrower than the Bugatti, the airframe of the 100P could be used withouth any other changes than bringing back the pilot seat to install the HS 404 cannon.
Perhaps reducing the number of machine guns to just four to compensate the lower power of the HS 12Z.......