Which item is NOT an IPS 3 engine frame?

Which item is NOT an IPS 3 engine frame?

• A. Swirl Frame
• B. Front Frame
• C. Main Frame
• D. Scroll Case

Answer: (D)

The key idea is recognizing what counts as an engine frame versus other engine components. In the IPS 3 configuration, the structural frames provide the backbone that supports and aligns the core rotating parts and attach to the airframe—these are the front frame, main frame, and swirl frame. The scroll case, however, is a housing around the compressor that routes airflow into the diffuser; it’s a casing, not a frame. So it isn’t part of the IPS 3 engine frame set. That’s why the scroll case is the item that is not an IPS 3 engine frame.

The key idea is recognizing what counts as an engine frame versus other engine components. In the IPS 3 configuration, the structural frames provide the backbone that supports and aligns the core rotating parts and attach to the airframe—these are the front frame, main frame, and swirl frame. The scroll case, however, is a housing around the compressor that routes airflow into the diffuser; it’s a casing, not a frame. So it isn’t part of the IPS 3 engine frame set. That’s why the scroll case is the item that is not an IPS 3 engine frame.