Peter S
Diamond
- Joined
- May 6, 2002
- Location
- Auckland, New Zealand
A while ago Franco alerted me to this project, I have just found their website.
I think the plan is to fly an original BE2e aircraft. The original engine was not usable, so it was decided to manufacture a new engine, in fact I think more than one was made.
It is an RAF.1A, an air-cooled V8, originally from around 1912-13 I think, and based on an earlier Renault engine which appeared in 1909-10. Note the F-head with exhaust valve on top (a bit unusual). I think the capacity is 537 cu inch (8.8 litre) and rated at 90 hp at 1600 rpm.
Normally these engines are described as having the propellor driven off the cam shaft, however I guess a less alarming description would be to say the camshaft is driven by the propellor reduction gearing! This is an early sucessful example of reduction gearing as most engines of the era (including this one) didn't run fast enough to require reduction. Also, author Herschel Smith points out that 2:1 reduction is not ideal, as the same teeth get the same loading on every revolution, this loading being a pulse - the uneven delivery of torque as each cylinder fires. However at 90 hp it worked, and as long as the mixture was kept very rich, the engine didn't overheat, and so it was known as a reliable if primitive engine.
There are other pages on this website, but this one shows some of the machining:
http://www.cams.net.nz/RAF-A1-Engine-Manufacture.htm
I think the plan is to fly an original BE2e aircraft. The original engine was not usable, so it was decided to manufacture a new engine, in fact I think more than one was made.
It is an RAF.1A, an air-cooled V8, originally from around 1912-13 I think, and based on an earlier Renault engine which appeared in 1909-10. Note the F-head with exhaust valve on top (a bit unusual). I think the capacity is 537 cu inch (8.8 litre) and rated at 90 hp at 1600 rpm.
Normally these engines are described as having the propellor driven off the cam shaft, however I guess a less alarming description would be to say the camshaft is driven by the propellor reduction gearing! This is an early sucessful example of reduction gearing as most engines of the era (including this one) didn't run fast enough to require reduction. Also, author Herschel Smith points out that 2:1 reduction is not ideal, as the same teeth get the same loading on every revolution, this loading being a pulse - the uneven delivery of torque as each cylinder fires. However at 90 hp it worked, and as long as the mixture was kept very rich, the engine didn't overheat, and so it was known as a reliable if primitive engine.
There are other pages on this website, but this one shows some of the machining:
http://www.cams.net.nz/RAF-A1-Engine-Manufacture.htm