I share with you my reasoning on the subject. That said, it's just a non-expert's point of view...

For what follows, I'm going to refer to 2 documents:

the booklet “Information on the Lorraine 12 Eb 450 hp engine” published by the Centre d'Instruction des Spécialistes de l'Aviation - Ministère de l'Air. (School for training Air Force mechanics between 1916 and 1928.)

The article published in the July-August 1921 issue of “La Houille Blanche ‘1 , ’LES PRINPAUX ACIERS DE CONSTRUCTION”, by P. Dejean.


Today, standards for the quality and nature of steels (alloyed, non-alloyed, hard and non-hard, ductile and non-ductile, etc.) comply with standardized industrial quality norms. For example, US standard 12L14 is similar to French standard S300pb (European designation: 11SMnPb37 or 1.0737).

S' refers to 'Structure', designating steel for the construction of structures or objects; ;
300 refers to the strength of the material (yield strength expressed in megapascals);
pb' refers to lead.

I'm no specialist, but all this is harmonized via a unified system: the UNS. In the 1920s, I doubt that such international equivalents existed.

From the “Houille Blanche” article, we can see that in France, steels in the 1920s were mostly classified according to their ductility: extra mild, mild (Adx), semi-soft, semi-hard...

Subsequently, they were classified according to their mechanical properties, since this was the main concern in industrial applications. As time went by, the composition of the steel, the alloy, became increasingly important, particularly for the application of heat treatments. Nowadays, the content of various chemical elements is also indicated.

The interest of the “Houille Blanche” article is that it proves the classification in use in France in the early 1920s for the 14 “grades” of steel, for predetermined uses. However, these « grades » are only basic, not comprehensive.

Each forge had its own classification with steels of similar grades...

 
This document tells us that a steel called “semi-soft carbon” (class B) corresponds to a chemical composition mostly close to that of S300pb or 12L14. The phosphorus content is identical (.35), the sulfur content is very similar (.35), as is the carbon content (.15).

Track the others components is not an easy task since no standard classification from chimical composition didn't exist at that time.

To my great regret, for our Lorraine 450hp, I was unable to find any open-source details on the composition of this perticular engine's cylinders.

The manufacturer's service manual is fairly brief on the subject (page 17): “The cylinders, made of special steel, are machined separately and worked as a whole."

In France, at the time, the term 'special steel' meant steel generally alloyed with elements other than carbon and for a specific use...

We can only deduce that each cylinder is machined, milled directly, in the Lorraine workshop, from a steel 'ingot'. These 'ingots' must have been specially ordered directly from a French foundry (St Chamont, Le Creusot, Holtzer, Châtillon, for the best known...). I will try to find out which one was commonly used by Lorraine.
 
On the other hand, the leaflet “Information on the Lorraine 12 Eb 450 hp engine” gives a rather interesting piece of information (page 9):

“In semi-hard, forged steel, taken from the mass and machined separately.”

Now, according to the “Houille Blanche” article, a standard semi-hard steel had the following characteristics in 1920:

generally between 0.28 and 0.34% carbon content;
Phosphorus: 0.035%;
Sulfur: 0.035%;
silicium (between 0.10 and 0.60%).

Lead is not indicated.

Regarding french 'acier spécial' ratings, according to the “Houille Blanche”, there was another 'grade' : The 'F' or, « Mangano-silicieux' (Manganese – Silicious ally Steel ?) which was a typical spécial steel used for aircraft engine's cylinder :

« It is worth noting that this steel, which has been used  for a very long time, received a new application during the war, a new application which has given it a new lease of life. This was its use in aircraft engine cylinders engines. In practice, it was recognized that cylinders made in this way were better able to withstand the high temperatures  than carbon steels of corresponding hardness. »

I found others writings that  supports that statement.

Typical 'F' grade alloy steel composition was as follow (according  the “Houille Blanche ») :

Carbon : 0,40/0,60 %
Silicium : 1,6/2%
Manganese : 0,30/0,50%

However, according to other sources ( “Métaux et leurs conditions d'emploi dans l'industrie moderne, caractéristiques, essais” - Jean Oertlé, 1918), the more frequent use of this special steel used more manganese and less silicium, for reasons of brittleness:

Carbon : 0,30/0,60 %
Silicium : 1,00/2%
Manganese : 0,30/1%

If I understand correctly, in France in 1920, the combined use of silicium and manganese made it possible to use much softer steels for similar applications requiring strength, ductility and good deformation and temperature behavior. This brings us closer to 12L14. 


So it's not at all impossible that French forges and manufacturers were using special steels with chemical characteristics were very close to those of 12L14 as early as 1920.

For Lorraine, it's just a question of finding out which one...

Hoping this personnal guess could help a little.

And the second one... Knowing that the fuselage at engine mount level measures 120 cm, we can measure that the cap in question is 8 cm or thereabouts... Of course, we'd need to know the depth of field to correct the perspective somewhat...

First one, hoping it will be uploaded....

Welcome back Renaud! Glad to have you return to the fold, so to speak!
I am always amazed at how some people get all defensive when they don't like or agree with materials or ideas presented to them. I always figure you should at least evaluate what they have before just outright dismissing them. But you can never tell with some people!

Thank you for your assistance in the past, and hopefully now and in the future!

That's very interesting Renaud!  Thank you for remembering Ric and Tighar and offering your help.

I own a copy of the following books:

"Pierre Levasseur et ses avions " TMA 2002;

"Les avions de Pierre Levasseur" LELA PRESSE 2004.

There are two interesting photographs inside which reveal a little of the cap that covers the water reservoir at the head of the cylinders.

I'll try to scan them tomorrow at work. For what it is worth. From what I've been able to measure, the cap is about 8 cm in these photos, and the pipe it covers about 6 cm.

Bonjour from France!

First of all, let me introduce myself. My name is Renaud Dudon and i am a lawyer in the civil life.

In 2000, I was a member of TIGHAR for a year on the initiative of Charles F. Sivert, with whom we carried out a short, unsuccessful search for the famous “Gremlins” found by your association in the Maine woods.

Perhaps you have some rememberance of this, Ric. It was a long time ago.

Unfortunately, I was unable to establish any link between this object and any equipment in France. I was even met with outright hostility to my research from certain 'knowledgeable' and well-authorized circles in the field of historical aviation in our country. I never did find out why the mention of the TIGHAR didn't ring true in their ears, and why the doors remained closed.

Occasionally, if you wish, we could talk about this subject, but that's not the primary reason for this message.

Since then, I've always kept an eye on your research and investigations, particularly on the Forum. I must say that your way of reasoning and humble approach to these mysteries calls for a certain respect. Of all those who claim they know how and why Nungesser and Coli disappeared, TIGHAR is the only organization to have, in my opinion, attempted an approach that is both scientifically and pragmatically based.

I've studied this disappearance a little with my limited resources. Many authors in France have come up against this persistent mystery. If I can help a little, I'd be glad to.

Of course, the veil of the unknown cannot be opened so easily, even in the eyes of the researcher who adopts suitable method.

Thanks for reading ! 

Back in mid-february, TIGHAR put out two e-mails regarding the forum upgrade; I understood that it would happen by the end of February.  I haven't noticed any differences (at least on the forum side).  Just curious if the upgrade did happen.

Randy Jacobson

One can hope that there are more drawings done by M. Soulier
adr

https://gallica.bnf.fr/ark:/12148/bpt6k6568023j/f29.item.r=LevasseurL'Aeronautique