Gazelle Engine
 

Chaps,

Could any of the guys out there with experience of the Gazelle give any views or opinions of the operation and behaviour of the Astazou engine in the Gazelle.

I'm interested in people's thoughts on the single shaft arrangement.

Technically, it has a slightly worse torque characteristic with drooping engine speed than the conventional two shaft engine...but is it significant? Does the engine have any detrimental characteristics relating to RPM control, low RPM recovery or any such matters? Or is it generally considered to be a benefit not to have to worry about the gas generator's RPM? I guess that given that the Gazelle has bags of power low RPM is less of a practical concern.

Do people like the ability to run the engine without the rotor system being engaged?

All thoughts and comments welcome.

Thanks
CRAN

Only a few hours on it but if i recall corrctly, the Aztazou in the Gazelle was fixed RPM with no free power turbine, therefore engine RPM was not a concern. This did affect high altitude performance though.

The ability to run the engine at without engaging the rotors was only a minor benefit for offloading pax etc without a full shutdown; there were no hyds or generator online.

Yes the reset governor maintained the Ng at 43.700 if I remember correctly.

You had either a transmission Tq limit or an engine Tq limit to consider with a typically French tiny torquemeter with a rotating bezel and a flashing red light.

It is a very robust and reliable engine with few vices.

The single shaft arrangement means you have the additional mechanical clutch/freewheel arrangement and this part has been known to fail.