In 1962, a Navy captain named Robert Truax, working at Aerojet General, submitted a design that made Wernher von Braun's Saturn V look modest. The Sea Dragon was to be 150 meters tall, 23 meters in diameter, and lift 550 metric tons to low Earth orbit — nearly four times Saturn V's payload. It would cost roughly $60 per kilogram to orbit in 1963 dollars (about $500/kg today, comparable to a fully expended Falcon 9). It was reviewed independently by TRW at NASA's request, who concluded the design was credible.

Truax's insight was heretical: rockets were being built wrong. Aerospace machined every bracket, aged every propellant tank in clean rooms, and treated launch vehicles like jewelry. Truax — who had launched actual rockets from the Pacific with his Sea Bee (1961) and Sea Horse (1961) test vehicles — argued rockets should be built like ships: 8mm rolled sheet steel, welded in a coastal shipyard, floated to the launch site by tug, ballasted with water until it stood vertical in the ocean, then fired directly from the sea surface. No launch pad. No crawler. No 40-story gantry.

The engine specs were absurd and, on paper, tractable:

• First stage: a single 80-meganewton pressure-fed engine burning RP-1/LOX. Chamber pressure only 20 bar — because pressure-fed engines are dumb, cheap, and reliable.
• Second stage: a single 63-meganewton engine burning LH2/LOX at 7 bar.
• Reusability: the first stage would splash down and be towed back. Refurbishment estimated at 2 weeks.

TRW's 1963 independent review concluded the ballistic launch approach was sound, the sea environment reduced acoustic loads (water absorbs the exhaust roar that would shatter a land pad), and the pressure-fed cycle eliminated the turbopumps that consumed most of the F-1 engine's development budget.

Why it died: nothing technical. The Apollo program had committed to Saturn V's architecture in 1961 — kerolox first stage, hydrolox upper stages, land launch from Complex 39. By 1965, NASA's post-Apollo budget was contracting under LBJ's Great Society priorities and Vietnam. Nixon's 1971 decision to fund the Shuttle instead of a Saturn-derived heavy lifter killed every "big dumb booster" study. Truax left Aerojet, formed Truax Engineering, and spent the 1970s building the Volksrocket series — including the rocket that Evel Knievel used to jump the Snake River Canyon in 1974.

Why 2026 changes everything:

• SpaceX's Starship is 121 meters tall and lifts ~150 tons. The industry has re-learned that bigger is cheaper per kilogram — Truax's core thesis.
• Modern shipyard automation (robotic welding, thick-plate steel joining developed for LNG tankers) makes 23m-diameter pressure vessels routine. Korean shipyards weld larger structures every week.
• Pressure-fed engines are back in vogue: Stoke Space's Nova, several New Space startups. The turbopump-free approach eliminates the single most failure-prone subsystem.
• Sea launch has been demonstrated commercially (Sea Launch Zenit, 1999–2014, 36 launches) and by SpaceX drone ship recovery. The maritime infrastructure exists.
• Payload demand finally justifies 500-ton class: orbital solar power stations require ~10,000 tons in orbit; a Mars city requires similar mass.

Truax died in 2010 at 93, holding 30 patents. His files at Aerojet — including the full Sea Dragon design study TDR-63-116 — are still in NASA's archive. Someone should read them.