Which engineers later crossed into executive command?

Which officers specialized in engineering and later became executive captains or admirals?

No example could be named from memory; the question needs Simon Harley's career research, and the 1922 changes complicate the path.

The viewer asks for examples of officers who specialized in engineering and later crossed into executive captain or admiral appointments. The answer declines to guess from memory and identifies Simon Harley as the person to ask. Another change to the scheme in 1922 also makes a single career diagram difficult to follow across the whole period. The exchange distinguishes the named captain-engineering promotions that follow from evidence of an officer actually crossing back into executive command.