Some say it looks crude, small, and simple, yet the Mercury capsule embodied an engineering beauty. Everything needed to sustain a man squeezed in a cone-shaped capsule measuring just 6 ft. 2 in. across at its base, weighing a ton-and-a-half. Astronaut must be less than six feet tall in order to fit inside. They joke you didn’t get in a Mercury capsule, you put it on.
The spacecraft, weighing less than 3,000 lbs., stands 9 ft. 7 in. tall, tapering to a can-shaped nose holding antennas and parachutes. At the base, a heat shield protect the capsule during the fires of re-entry. On orbital flights, it functioned by sacrificing itself in a process called ‘ablation,’ meaning that it would slowly burn away, boiling off the heat as it did. An alternative beryllium “heat sink” shield will be used to protect the capsule from the lesser fires of the suborbital flights — 1,230 degrees (F).
A retropack, like a round hatbox, is centered against the heat shield, held in place by three metal straps synched to the edge of capsule. The pack holds six solid-fuel rockets — three “posigrade” rockets to push the capsule away from the spent booster after launch, and three larger ones which fired to slow the capsule just enough to allow gravity to pull it out of orbit, toward an ocean splashdown. The first flights, however, will be lofted by the small Redstone, with just enough thrust, 78,000 lbs., to lob the capsule on an up-and-down ‘suborbital’ flight.
The Mercury capsule represents a elegant, lightweight solution to problem of putting a man in space, every part functional, pleasing in geometric form, a man-made conch shell whispering of the endless ocean of space.
It’s 60 years ago — May 5, 1961. You are Alan B. Shepard, Jr., age 37. All element of Mercury-Redstone 3 are ready. You are ready — ready this day to become, even if on a brief flight, the first American in space.
Through darkness, through the beat of breakers staggered along the shore. On the wind crossing the grassy dunes, onward across the concrete apron. Sifting winds and sifted sand washing against the electronic echo of voices, voices squawk-box cut and compressed.
Prepare to resume the count.
Wave patterns settling on the sand, sand faintly capturing the fallen light. A clear sky at last, stars and a half moon. A cold front that has stalled the launch attempt since May 2 has cleared.
Across the grassy dunes, filaments buzz with current, a flutter of light, locking into steady beams from an arc searchlights, grazing the ground, focusing on Pad 5. Approaching midnight, floodlights blind the stars, carve harsh shadows around the A-frame gantry of Pad 5. Shadows rise and fall, are cut by light and mix with it; both mixing with the men working the rocket toward life.
And we’re counting.
Counting down, aiming for a 7 a.m. launch.
Enfolded in the gantry’s bulky shoulders, wrapped in cramped clean rooms, obscured by platforms and pipes, clamped atop the rocket, spires an early production Mercury capsule, #7 which will ride, by coincidence, Redstone #7.
You are awakened at the Hangar S crew quarters at 1:10 a.m. to the words, “They’re filling the tanks.”
You step out of the transfer van, silver suit shining, stepping into the predawn light of floodlamps at Pad 5. The white looping shadows, gantry and fuel lines snaking across the concrete pad, a thin white form, mists of super-cold propellant shedding from the rocket’s slim side and hissing from the ground pipes into a ground swirl.
Standing a moment at the base of Redstone #7 rocket, sliding a few steps to the left for a better view, gaze up, shield your eyes with a gloved hand against your helmet. Stand toe-to-toe with rocket. The Redstone, no creature of romance, a straight tube resting on stubby fins . . . looks beautiful. The bottom half of the rocket plated in frost, signature that it is loaded with liquid oxygen. The top half, shows clean skin painted white with black tracking stripes. Invisibly filled with alcohol fuel. From the stubby fins resting on the metal ring of a launch pedestal to the spike tip of the escape tower, 83 feet.
The moment passes, you move in careful steps toward the elevator cage. The ground crew applauds. Too flush with emotion to speak, you walk to the elevator that will take you to Level 3, the white room — which is actually painted green. It’s 5:15 a.m.
You cross to the capsule, past the side painted with the name you have chosen, “Freedom 7.” Helpful hands assist you in wiggling through the hatch, just 3-feet square. The same hands adjust the web of straps securing you to the form-fitting couch. It’s 6:10 a.m. One last handshake and the heavy hatch is lifted into place, the fingers at its edge disappear. Your heart rate jumps. You are alone.
Through the capsule’s fish-eyed periscope lens, you watch — someone flashes you the OK sign. The pad crew departs. At 6:34 a.m., the gantry rolls back; the Redstone stands alone. The periscope shows clouds glowing in the light of sunrise.
T minus 15 minutes. And holding. Clouds of the cumulus kind roll in from the sea, no-go for visual tracking. However, estimating this patch of cloud cover should clear in 30 – 45 min.
The blockhouse is reading a failure in an inverter in the Redstone, which converts DC battery power to AC — voltage out of parameters. This is a no-go for launch, the inverter must be replaced. Estimating 52 min. to replace the inverter. Recycling the count to the T minus 32 minute mark and holding there. The gantry, which had been moved back, is rolled against the rocket, and the pad team returns. Christ, you need to relieve your bladder. No way around it, Buster.
Eighty-seven min. later, 8:40 a.m., the rocket again stands alone, needled into the clear sky, a few clouds lingering offshore. Counting again. We’re go for launch.
Twenty min. later, the count is halted, a problem far away, a tracking computer, an IBM 7090, at the Goddard communications center in Maryland has failed and must be rebooted. It takes 17 min. to baby back to life.
Controllers spot a high pressure reading in the oxidizer tank of the launch vehicle. Could it be a malfunctioning valve? T minus 2 min. 40 sec. and…holding. The team discusses replacing, which would mean scrubbing the launch. Hesitation crosshatches the voices on the loop.
You’ve had enough of this, inside the capsule for nearly four hours. “I’m a lot cooler than you are. Why don’t you fix your little problem and light this candle?”
The ground team already has figured out a way to open a valve remotely and bleed off the excess pressure.
All elements ready. Resume the count. T minus 1 min. and counting to a 9:34 a.m. launch.
You report, “Roger, periscope has retracted.”
Mercury umbilical out. The thin boom feeding the capsule falls back in an arc. T minus thirty…. Fully focused, braced for the jolt, righthand primed to start the elapse-time clock, lefthand on the abort handle that would fire the escape tower, you don’t hear the final calls until . . .
You hear, “. . .Main stage, ignition.” Punch the liftoff clock.
Liftoff, 34 minutes past the hour.
Surprisingly smooth. “The clock has started. We’re underway.”
The rumble of the engine is less than you expected. You easily can hear the radio.
Muscles relax. “We’re go.”
This is Freedom 7. G-forces increasing . . .
And after 45 sec. — she’s starting to shake.
We’ve entered the transonic phase, approaching maximum dynamic pressure, 84 sec. into the flight, the convergence of air density and velocity into the maximum pressure on the skin of the vehicle, called “Max Q” in engineering language. Max Q at 1 min. 24 sec. after launch. A brick wall to push through. Vibrations building, noise increasing, vision blurring, rattling the cage . . . for five, ten seconds. Vision blurred, barely can read the instruments, but you radio no hint of it, lest some fool panic and call for an abort. For ten seconds rattling before like a breath, noise and vibration releasing, 87 sec. after launch. “A lot smoother, a lot smoother now,” to call, a hint of how rough it’d been.
Calling down the numbers, fuel, oxygen, cabin pressure, G forces We radio status every 30 seconds — just to assure everyone everything is OK. We’re go. Rifling the word GO, a bullet through the radio static. Two minutes, riding pretty, pitching over on time, the Redstone nodding to the horizon falling away unseen below. Feeling great, a sweet moment. Still go, go all the way.
Coming up on booster burnout. BECO, forces building to 6.2 Gs. Cutoff, right on the mark, 2 min. 22 sec. after launch. Followed immediately by tower jettison.
Up on the tower, the solid-propellant escape rocket fires through three nozzles, tractoring the red superstructure away like a Fourth-of-July bottle rocket.
The light is green, tower jett.
Standing by for cap sep. Coasting uphill on the dead rocket for ten seconds. Waiting the for critical event — if you don’t cut loose from the dead booster, it’ll be a bad day — your pulse shoots up.
A noise pulse, the thump of the three small posigrade rockets firing, a one-second kick to pull the capsule away from the Redstone. “Cap sep. is green.” Five seconds later, the Automatic Stabilization and Control System (ASCS), the autopilot, begins turning the capsule around, head shield forward. In the cockpit the three attitude needles, pitch, yaw and roll, swing around. Turnaround proceeding OK, to be maintained during the orbital flights to come. ASCS working well; periscope is coming out and ASCS is OK. We’re in position, 3 min. since launch, the blunt end canted 14 degrees above the line of travel. Facing backwards, blunt end first, with the protruding retropack leading the way. Capsule’s systems humming along, the whir of fans and inverters, the crackle of the radio sound an electronic symphony. Freedom 7 is alive!
A stray metal washer floats from the depths of the capsule. You reaches for it, misses, sending it tumbling away.
You ride an arc breaking the skin of the atmosphere for just five minutes, a testing taste of the orbital flights to come, a compressed workout of all the systems.
Proceeding directly to test of manual control, just 10 sec. after capsule turnaround.
You pull the T-shaped handle to the left side of the instrument panel. “Manual handle is out.”
Working the maneuvers with the pistol-grip hand controller on your right, only 40 seconds allotted for testing the system, cautiously, one axis at a time. Eyes on the instruments, the needles of the attitude indicators. Manual pitch. Pitching the nose down and back. “Pitch is A-OK.”
Manual yaw. Swing the nose to the side and back. “Yaw is A-OK.”
And last — roll. Running out of time. Cut is short, just long enough to report, “Roll is OK.”
Fighting the clock, you’re five seconds behind the schedule.
Time for observations through the periscope, the view thrown on a ground-glass display at your knees. Only 15 sec. planned for this — and you’ve left a gray filter on, and this is no time to fumble with it. Leave it on — the view is murky, nearly colorless. Still you give the obligatory report, “Oh, the view is tremendous.” You’re looking back at the Cape — the whole state of Florida, across to the Gulf and down to the Keys. Up the Atlantic coast into the Carolinas, the breezes keeping the clouds offshore. Lots of clouds, especially directly below. The Bahamas down there somewhere. An island peeking out now and then. Can’t identify which ones.
Capsule approaching the top of its trajectory, 115 miles up — which we’ll reach just 5 min. 11 sec. into the flight — exhausting the last of its upward momentum. You switch to a second manual control system, the fly-by-wire that manually commands the automatic system.
The call comes fast from Mercury Control, time to retro sequence. Eyes back on instruments, counting toward retrofire. Maneuvering to retro attitude, nose canted down 34 degrees, a test of the retro system that will be needed to pull future flights out of orbit. In position. “Control is smooth,” you report. Switch to automatic ASCS to hold position.
The three rockets in the retropack fire into the flight, ripple fired at 5-sec. overlapping intervals, 20 sec. total firing time. “Retro One, very smooth.” Firing with a roar, 5 min. 13 sec. since launch. You feel gently pushed back into your couch. “Retro two. . . Retro three.”
“All three retros have fired.” A bit low on pitch, you nose her up.
Time to try a second manual control system, the fly-by-wire, manually controlling through the electronics of the automatic system. Yaw maneuver, using the periscope as visual reference. Cape Canaveral hanging out there makes a great reference point.
Six min. since launch. Standing by for jettison of the retro pack. You hear the retaining straps release, one the scope sees debris and the end of one of the three straps. But the “jett retro” does not light up on the row of sequence indicators on the left side of the instrument panel. Probably just a faulty light. You hit the manual override, and the light comes on. Retro jettison is green.
Try to see out the two portholes, just 10 in. in diameter, on left and right, attempting like Gagarin to see a star. Can see a thing out of them. Wasting time, falling behind schedule.
Losing time, Just 6 min. 49 sec., since launch, but already time to pull into re-entry attitude manually using fly-by-wire.
At the seven minute mark: “OK, Buster, re-entry attitude. Switching to ASCS normal.”
So swiftly that it surprises you, the 0.05-G light comes on, indicating the initial thin grasp of atmosphere tugging at the capsule. For the first time, you feel behind the curve. Wanted to make more maneuvers, but no time. Hey – G forces rapidly spike up, within seconds. The capsule is being yanked down, the graceful arc of spaceflight pulled violently into a hardline plunge. The capsule is rolling counterclockwise along its long axis, as planned, 10 degrees per second.. Out the right porthole, you glimpse the horizon, a fuzzy gray above it, then the deep blue of space. Capsule quivers as the atmosphere bites into it.
Eight min. since launch. Forces multiplying with each tick of the clock. Three Gs….six….nine. But you’ve been trained to take, to force air in and out of his lungs in punched breath, punching out “OK” over the radio to show you’re taking it. “OK…OK” Building in just a half a minute, maximum force more than 11 Gs. OK.
And releasing just as swiftly. “This is Seven, OK.”
Standing by for drogue chute.
The small pilot parachute mortars from the top of the capsule. Just 6 ft. in diameter, stabilizes the descending capsule. Steady as she goes.
Standing by for main chute at 10,000 ft. Main chute is out, reefed. At first the chute is hobble-skirted to reduce the shock of opening. Reef lines cut, it blossoms to its full 63-foot diameter, a full canopy, striped red and white, gripping the air.
Main Chute . . . looks good.
Just ten-and-a-half minutes since launch. The leisurely descend, swaying under the parachute, will command a third of the total flight time.
Standing by for landing bag deployment. Two minutes after main chute, the heat shield releases, drops down a few feet as a rubberized landing bag fills with air to cushion impact.
Coming down about 302 mi. east of Cape Canaveral.
Ready for impact. You raise his visor, loosens the neck ring of his helmet, loosens some of the straps binding him to the seat. Just in case on impact he must make a quick exit.
Punching through the clouds. Helicopters from the aircraft Carrier Lake Champlain already in the air. Circling overhead.
You call to the recovery forces, “I’m about 1,500 ft. now. The main chute still looks good; the rate of descent is indicating 30 feet a second” — about 20 mph.
After 5min. under the red-and-white striped main chute, brace for splashdown. Splash, a seat-of-the-pants jolt. The capsule heaves over, slowly rights itself.
The capsule is floating OK.
The prime recovery copter moves in, lowers over the capsule, it’s rotor pushing a crater-like circle of water, hooks a line to the neck of the capsule…lifts it slightly above the waves. You releases the side hatch. The copter lowers a horse-collar sling and lifts you to the open side of the chopper.
Just 11 min. after splashdown, you step onto the carrier, moves lithely, catlike. Astronaut onboard.
We’ve done it. To space and back – all in just 15 min. 22 sec.