Instead of getting the necessary clearance by moving the engineer forward, they should just make the engines oval.
Making the cowls oval won't help the fact that the
engine itself still needs to be round. Remember everything that's inside amounts to a collection of vary rapidly rotating fans - you can't just make a fan blade oval, much less one that spins at 10,000RPM.
If they get much larger they are going to have to flip them back onto the top of the wings where they were in the old days. I've seen radials and turboprops mounted high, but never a turbofan. I wonder if there is a technical block or just packaging. More power=dive would not be an ideal handling characteristic though. The props let you move the centre of effort much closer to the wing.
Some of the reasons it's not more commonplace is more simple reasons such as maintenance (a hanging engine is way easier and less risky to re-and-re vs an overhead engine), simple physics on how strong the pylon it's attached to needs to be (try balancing a watermelon vertically on a ruler, now try hanging it by it instead), noise (the wing blocks a lot of the engine noise from the cabin/passengers when mounted underneath), safety (an engine that suffers a catastrophic uncontained failure is less likely to blow chunks into people when under vs over the wing), etc etc etc.
Three solutions for larger engines and ground clearances is...
1/ Use 4 smaller engines instead of 2 massive ones...but airlines don't like more of something that's very expensive. Each engine = extra money in maintenance, repairs, end-of-life replacement, etc etc etc.
2/ Increased use of the tri-jet design where there's 2 slightly smaller engines on the wing and 1 on the tail, IE the MD11. But we come back to the same argument as #1 above - airlines like LESS engines, not more. There's also structural concerns there as well since the airframe needs to be heavier to support that tail mounted engine, not to mention all the additional weight of the engine and it's gear itself. Weight = less stuff inside the plane = less profit. It also uses more fuel = less profit. I'm sure everyone sees where this is all going.
3/ Make the landing gear longer. A famous example of this was the Constellation. One of the things it was famous for it's "stilt" landing gear and resulting appearance, and it was solely to accommodate the required ground clearance for it's massive propellers it needed for it's size.
It's equally famous triple tail design, it was also a requirement (because of the landing gear) so that the plane would actually fit inside the maintenance hangers of the day - a traditional single or even double vertical stabilizer would have been too tall....yet 1 (or even 2) of the maximum allowable height of the day wouldn't have provided adequate rudder authority for such a large airliner of it's day.
But, these are all compromises that worked because money was of little consequence in that era - nobody cared that 3 tails or super spindly landing gear that was prone to damage and stress issues meant a drastically higher level of maintenance was required, or that 4 engines worked better than 2 in those days because it allowed airlines to boast about their speed they could move their passengers. They didn't care they burned a crap ton more fuel, either....money wasn't tight and profits were not made on the back of pennies split in 2 like they are today.
