Here's the actual paper by Admiral Melville, USN.[1] Melville was a naval steam engineer, the head of steam engineering in the Navy, and was responsible for many innovations in naval propulsion. There's a building at Annapolis named after him, and a statue. Not a Luddite at all.
So where did he go wrong?
First, he discusses airships. Balloons at low pressures, which maximize lift, are prone to collapse from wind gusts, he says. He dismisses rigid airships as too heavy. Writing that in 1903 is embarrassing. Count von Zeppelin had flown a prototype three years previous (it crashed), and by 1906 had a Zeppelin that worked. Within 20 years, the US Navy was a major operator of rigid airships.
For heavier than air craft, he writes: The step from the largest flying creature evolved by nature to the smallest flying machine that will meet the wants of man is, therefore, a very long one. To span that step man has, to help him, only a few mechanical contrivances and the superior strength of steel. Almost every other condition is set against him.
The first all metal airplane, the Junkers J-1 (1915), was all steel. It did fly, but was too heavy to perform well. By 1918, duralumin, an aluminum alloy, had been perfected.
Nobody did an all-steel aircraft again until the 1950s, with jet engines.
So he missed that substantial weight reduction was possible. He was familiar with steam-powered ship systems, where everything is big and heavy.
Any estimate that extrapolates known quantities of mechanisms is bound to be conservative leaving out the unlisted and unimagined changes that will dominate the needed effects.
Not necessarily. Rockets are still bound by the tyranny of the rocket equation. Rockets have only improved slightly since the Saturn V and the Space Shuttle, both designed over half a century ago. Chemical fuels maxed out a long time ago. Fission was too risky. Fusion is still stuck. Antigravity, which was seriously discussed in the 1950s, went nowhere.
So where did he go wrong?
First, he discusses airships. Balloons at low pressures, which maximize lift, are prone to collapse from wind gusts, he says. He dismisses rigid airships as too heavy. Writing that in 1903 is embarrassing. Count von Zeppelin had flown a prototype three years previous (it crashed), and by 1906 had a Zeppelin that worked. Within 20 years, the US Navy was a major operator of rigid airships.
For heavier than air craft, he writes: The step from the largest flying creature evolved by nature to the smallest flying machine that will meet the wants of man is, therefore, a very long one. To span that step man has, to help him, only a few mechanical contrivances and the superior strength of steel. Almost every other condition is set against him.
The first all metal airplane, the Junkers J-1 (1915), was all steel. It did fly, but was too heavy to perform well. By 1918, duralumin, an aluminum alloy, had been perfected. Nobody did an all-steel aircraft again until the 1950s, with jet engines.
So he missed that substantial weight reduction was possible. He was familiar with steam-powered ship systems, where everything is big and heavy.
[1] https://www.jstor.org/stable/pdf/25105260.pdf