Hello, I'm making this thread because there is a bit of an issue with sources pertaining to the engine powering the Renard R.36 prototype. I know a lot less about Hispano Suiza engines than about Renard fighters, so I need some help.
Primary sources from Renard often cite the HS 12Ycrs, or the "12Ycrs type 21" in later documents, which to my knowledge doesn't exist, and is probably a mistake from Renard who might have mixed up some engine designations.
In my mind, it was either the 860 hp 12Ycrs or the 910 hp 12Y-21, and since the commonly cited engine power for the R.36 is 910 hp, I assumed it was pretty obvious that the 12Y-21 was the right choice, especially since the "type 21" appeared in later documents.
However, and this might be incorrect, I have come across a few sources stating the 12Y-21 was not designed to fit a cannon through the cylinder banks, and the R.36 was supposed to have a cannon. So either the prototype didn't have a cannon, which would be weird since it went through armed military trials, or it isn't a 12Y-21.
But this concern flew out the window when I realised these engines all had a right-hand rotation. Looking closer at the R.36 propeller (attaching a few pictures), it seems to be fitted to spin counterclockwise. Test reports also indicate that engine torque made the R.36 roll to the right in a climb, like with a left-hand rotation engine.
So, either I'm confused, or the R.36 prototype was fitted with an entirely different 12Y engine. I can't be sure of the 910 hp figure anymore, nor am I certain the cannon was actually fitted to the prototype. All I know is that the engine spun counterclockwise and that a constant speed propeller was used by around September 1938.
Could anyone be able to help me figure out which HS engine powered the R.36 prototype?
Primary sources from Renard often cite the HS 12Ycrs, or the "12Ycrs type 21" in later documents, which to my knowledge doesn't exist, and is probably a mistake from Renard who might have mixed up some engine designations.
In my mind, it was either the 860 hp 12Ycrs or the 910 hp 12Y-21, and since the commonly cited engine power for the R.36 is 910 hp, I assumed it was pretty obvious that the 12Y-21 was the right choice, especially since the "type 21" appeared in later documents.
However, and this might be incorrect, I have come across a few sources stating the 12Y-21 was not designed to fit a cannon through the cylinder banks, and the R.36 was supposed to have a cannon. So either the prototype didn't have a cannon, which would be weird since it went through armed military trials, or it isn't a 12Y-21.
But this concern flew out the window when I realised these engines all had a right-hand rotation. Looking closer at the R.36 propeller (attaching a few pictures), it seems to be fitted to spin counterclockwise. Test reports also indicate that engine torque made the R.36 roll to the right in a climb, like with a left-hand rotation engine.
So, either I'm confused, or the R.36 prototype was fitted with an entirely different 12Y engine. I can't be sure of the 910 hp figure anymore, nor am I certain the cannon was actually fitted to the prototype. All I know is that the engine spun counterclockwise and that a constant speed propeller was used by around September 1938.
Could anyone be able to help me figure out which HS engine powered the R.36 prototype?
