Apollo Command Module Parachutes
When Apollo astronauts came home from the Moon, the last thing standing between them and a hard crash into the ocean was a carefully timed bundle of parachutes. This is the story of how that system slowed a falling spacecraft from a fireball to a gentle splash.
Quick facts
- Formal name: part of the Command Module’s Earth Landing System (ELS) — the gear that recovered the returning crew capsule.
- Parachutes in the chain: nine total — one 7-foot apex-cover drag chute, two 16.5-foot drogue chutes, three 7-foot pilot chutes, and three 83.5-foot main chutes. (It is often summarized as “eight parachutes” when the apex-cover chute is counted separately.)
- Splashdown speed: about 22 mph (roughly 24–25 feet per second).
- Built by: developed by NASA with prime parachute contractor Northrop Ventura; the Command Module itself was built by North American Aviation.
- Materials: synthetic fabric (Dacron and nylon), nylon, steel, aluminum, plastic, and brass.
- Timeline: development began January 1962; the system was redesigned for higher loads after the January 1967 Apollo 1 fire.
What it is and how it works
The Command Module (CM) is the cone-shaped capsule that carried the three-person Apollo crew. Coming back from the Moon, it slammed into the atmosphere at about 25,000 mph — dozens of times the speed of sound. Its blunt heat shield (the thick protective base that takes the heat and air resistance of re-entry) did most of the slowing, but the capsule was still falling far too fast to hit the water safely. That is where the parachutes took over, firing in a tightly timed, automatic sequence.
At about 24,000 feet, small explosive devices called mortars — think of a launcher that throws a packed chute clear of the capsule — tossed off the forward heat shield, also known as the apex cover. Until that cover was gone, the mortars underneath could not eject the chutes. About 1.6 seconds later, two drogue chutes popped out. A drogue is a small stabilizing parachute that keeps the capsule from tumbling. They opened “reefed,” meaning a line cinched each canopy partly closed so the sudden jerk of opening was gentler; after about 8 seconds, small cutters released the reefing lines and let them open fully. The drogues steadied the CM and slowed it down, staying attached to roughly 11,000 feet.
Near 10,000 to 11,000 feet, the drogues were cut loose and three small pilot chutes were mortar-fired. Each pilot chute dragged out one of the three big 83.5-foot main canopies. Like the drogues, the mains opened in reefed stages — partly, then fully — to spread the braking force out over time, the way a car eases to a stop instead of slamming the brakes. Fully blossomed, the three mains lowered the capsule the rest of the way to its roughly 22 mph water landing.
Why it matters
Once re-entry began, there was no backup plan and no place to abort. The parachute system was the final, non-negotiable link in bringing the crew home, so it had to work every single time. The engineers built in deliberate redundancy: three main chutes where only two were needed, duplicated electrical sequencing logic, and the staged reefing that limited opening shock. The design was so robust that even with one main chute failed, the remaining two would still give a survivable landing of about 25 mph. It became a textbook example of human-rated recovery design — engineering trusted with people’s lives.
Notable examples
- All crewed Apollo missions (Apollo 7 through Apollo 17): every Command Module came home under this three-main-chute system. The lunar missions splashed down in the Pacific, while a few of the early Earth-orbit flights (such as Apollo 7 and Apollo 9) landed in the Atlantic.
- Apollo 11 (1969): the system brought Armstrong, Aldrin, and Collins to a Pacific splashdown after the first crewed lunar landing, using the standard 16.5-foot drogues and 83.5-foot mains.
- Apollo 15 (1971): the most famous proof of the design. One of the three main chutes collapsed during descent, yet the redundancy let the CM splash down safely on the remaining two at roughly 22 mph.
- Skylab and Apollo-Soyuz (1975): these later flights used the same Apollo CM and its parachute landing system.
- Modern descendants: the drogue-then-main ringsail approach influenced later crew capsules, including NASA’s Orion spacecraft, which still descend under multiple reefed main parachutes.
