I'm no expert but based on these photos [1] it looks like they're only transporting the engine core. What we normally call an "engine" on an airliner is really

I'm no expert but based on these photos [1] it looks like they're only transporting the engine core. What we normally call an "engine" on an airliner is really a relatively small engine core with a huge fan on the front. The white donut-like object is probably blocking airflow through the core to minimize drag. [1]: https://www.flightradar24.com/blog/how-qantas-ferried-an-engine-on-the-wing-of-a-747/ https://www.flightradar24.com/blog/how-qantas-ferried-an-eng...