25 Dollars - Elizabeth II de Havilland Comet

The de Havilland Comet, which entered commercial service with BOAC in May 1952, was the world's first jet-powered airliner — and its early career ended in catastrophe. Two Comet 1s disintegrated in flight in 1954, traced eventually to metal fatigue cracking from the square window corners, which concentrated stress through repeated pressurization cycles. The disasters grounded the entire fleet and handed Boeing and Douglas the opening they needed to dominate commercial aviation for decades.

Solomon Islands issued this coin through the Pobjoy Mint under a broader aviation commemorative program, a common vehicle for .999 silver rounds marketed to thematic collectors rather than circulation.