I have a few questions about jet engines and their starters, which I couldn't find the answer to after I did a search.
The search did remind me of certain facts such as .................
Bleed air to the starter is supplied from either the APU, a ground cart, or another engine. The starter will disengage at different engine N2% speeds (such as 48%N2) for different engine types. Starters are generally mounted on the accesory gearbox (AGB), etc, etc.
My questions are .......
Does a jet engine have a large "Flywheel" disc/ring with teeth all around it located somewhere among the N2 compressor blades that a pinion type gear from the starter meshes with (like in a car's engine) to start turning the engine during startup?
I understand that jet engine starters are caused to spin inside due to bleed air, but what I don't understand is what happens next ....... to start turning the engine's compressor blades.
The closest I've come to learning how this works was from this explanation from my search ......
"The starter turns the accesory gear box (AGB), which turns the quill shaft, which turns the main shaft."
That's fine info, but, I'd like to learn about it in finer detail.
I also learned these 4 terms from my search ...... Quill Shaft, Spline Shaft (about the starter), and N2 Spool, Rotor Spool (about the engine's main shaft).
So, armed with the above quoted statement, and these 4 terms, is it safe to say that when the starter is engaged, a spinning Quill Shaft extends from the AGB and meshes with a Rotor Spool which is a large flywheel?
Or, perhaps the Quill Shaft extends farther and meshes with a smaller gear (Rotor Spool) on the main engine shaft deeper inside the engine?
Sorry for the long post guys. I'm just trying to put these pieces together.
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