April 1982:American manned spacecraft recovery

When the Space Shuttle Columbia returned to Earth after its
maiden flight, the aircraft-like spacecraft made touchdown on
a runway at Dcryden Flight Research Center in California. This
was a major departure from previous American spacecraft
landings: all of which have been by parachute at sea. This
article is intended to summarise the thirty-one American
manned splashdowns which took place in the Atlantic and
Pacific Oceans during the period 1961-1975.

Mercury

It was in late 1958 that a study began on manned spacepraft
recovery operations. It had already been decided that water
recovery was more favourable than land recovery. Many felt
that retrieval operations could prove to be difficult: but with'
properly designed equipment, helicopter pickup could be
used. However, two and a half years were.to pass before the
first manned splashdown occurred.

On 5 May 1961 astronaut Alan Shepard became the first
American to fly in space during the sub-orbital. flight of
Mercury Redstone 3. Shepard drifted back to Earth under a
19m diameter Northrop ringsail parachute only 486km
downrange from the Cape Canaveral launch site. The small
capsule hit the water at 10 m/sec and the pilot compared this as
"a little abrupt, but no more severe than a jolt a pilot gets when
he is launched off the catapult of an aircraft carrier". The
splashdown, as with all Mercury landings, was cushioned by a
rubberised glass-fibre landing bag which was released when the
heat shield was lowered. Seconds after hitting the water, the
capsule flopped over on its side and it was only when the
reserve parachute was jettisoned that the spacecraft began to
right itself. Minutes later, one of the recovery helicopters
hooked on to the capsule and raised it slightly above the water.
Shepard then emerged, entered a sling and was then winched
up to the helicopter which transferred the astronaut to the
prime recovery ship, the USS Lake Champlain.

The recovery of the second sub-orbital mission. Mercury
Redstone 4. was by no means as successful. The capsule.
Liberty Bell, "hit the water with a good bump" and a few
minutes later while pilot Virgil Grissom was checking over the
capsule’s instruments the side hatch prematurely blew open,
apparently due to a short circuit. Sea water came rushing in
over the sill and Grissom, seeing what was happening, lunged
out of the hatch into the sea. In the process of doing this the
astronaut got entangled in the line which attaches the dye
marker package to the spacecraft, but fortunately managed to
free himself quickly. The helicopter crew, seeing the sinking
spacecraft, hooked onto it to lift it clear of the water, hut as this
was happening a red warning light appeared in the cockpit to
indicate that the helicopter's engine was overheating. This later
turned out to be a false signal. The capsule, however, was
released and sank to a depth of 4570m. Grissom who had been
swimming around for three or four minutes was then picked
up. but not before being dragged along in the water by
the helicopter before he was lifted up. tired and very wet. Thus.
Liberty Bell went down in the history books as the only
American manned spacecraft to be lost during a mission.
Following the loss of Mercury Redstone 4,a number of new
procedures came into being to prevent any recurrence of the
incident. These included a stipulation that the firing plunger
safety pin would be left in place until the helicopter hook was
attached to the spacecraft. Grissom had removed the safety pin
a short time before the hatch blew open. Also for future
missions an inflatable flotation collar would be fixed in place by
recovery swimmers.

John Glenn, in Mercury Atlas 6, was next to splashdown in the Atlantic after America's first orbital flight. The accuracy of this landing was not as good as the two previous landings, the
capsule landing some 64.5 km uprange. Friendship 7 "hit with a
good solid bump" and the capsule went far enough under to
submerge both the periscope and window. Glenn reported
later that he heard gurgling noises but no leaks were found. For
this mission the astronaut remained in the capsule until
"Steelhead". the code name for the recovery ship USS Noa.
came alongside. Twenty-one minutes after splashdown the
capsule with Glenn aboard was winched onto the deck where the astronaut blew the side hatch of the capsule and emerged none the worse for his three orbits of the Earth. A helicopter
later transferred the astronaut to the prime recovery ship, the
USS Randolph. It is interesting to note that the recovery forces
during this mission totalled twenty-four ships and one hundred
and twenty-six aircraft. the astronaut blew the side hatch of the capsule and emerged

When Mercury Atlas 7 splashed down on 24 May 1962 it was
412 km from its predicted impact point. The overshoot was
traced to a 25 degree yaw error at the time the retrograde
rockets were fired. The capsule listed 60 degrees to one side
after splashdown and astronaut Carpenter noticed that some
water had seeped into the cockpit. Rather than wait in the capsule Carpenter decided to exit the spacecraft via the top
of the craft and wait in the survival raft for pickup. The
astronaut got into the raft before realising that it was upside
down! Later, when recovery aircraft reached the area, he
signalled with a hand mirror and stxrn frogmen were in the
water attaching a buoyancy collar to the capsule to keep it
afloat. The astronaut was then picked up by helicopter and
taken to the USS Intrepid after being in the water for two hours
and fifty nine minutes. The capsule, Aurora 7, was picked up by
the USS Pierce and was found to contain a considerable
amount of sea water, the majority of which was believed to
have entered through the small pressure bulkhead when the
astronaut passed through the recovery compartment to get to
the life raft.

The landing and the recovery of the penultimate Mercury
mission, Mercury Atlas 8. went according to plan with the
spacecraft being recovered in the Pacific for the first time only
7.2 km from the predicted impact point. The splashdown of
Mercury Atlas 9. the last mission of the Mercury programme,
also went without a hitch. During the recovery the capsule was
sighted by the aircraft carrier USS Kearsarge and helicopters
were deployed to circle the spacecraft during its final descent.
After a flawless splashdown swimmers dropped from the
helicopters to fix the flotation collar and then a motor
whaleboat towed the spacecraft alongside the ship. Cooper did
not egress from the spacecraft until it was hoisted aboard the
ship, only 37 minutes after splashdown.

Gemini

In early 1961 NASA decided to adopt land landing as a major
Gemini objective but the means to that end, the paraglider
system, had yet to prove itself. The first active interest in this
landing system was in 1959, before the Mercury missions took
place. The paraglider was, as the word suggests, a gliding parachute
able to guide a returning spacecraft to a preselected site on
land. After ejection of the paraglider cannister at 15.000m the
paraglider would automatically take shape as gas inflated the 10 m structure. The pilot could bank.or change his rate of
descent and could glide his craft up to 32 km in any direction.
Cables attaching the paraglider to Gemini would be severed at
touchdown and Gemini would skid to a halt. However,
problems occurred with the ejection and inflation of the
paraglider from Gemini during tests and in early 1964 after a
string of failures the paraglider was dropped. Gemini money
was tight at this time and this may have been the immediate
reason for the cancellation of the paraglider project.

All ten Gemini.missions, like Mercury, landed by parachute
in the sea. The heavier capsule however was lowered to a
splashdown at 9m/sec by a 26m diameter ringsail parachute.
Another difference from the Mercury landings was that the
Gemini spacecraft lay in the water horizontally rather than
vertically.

Gemini 3, the first manned flight of the programme, landed
111 km short of the planned impact point due to insufficient
lift during re-entry. Shortly before splashdown the two
astronauts. Grissom and Young, suffered a severe jolt when the spacecraft assumed its landing attitude. After the main
parachute deployed, the spacecraft hung from it vertically with
its nose suspended at a single point. Just before landing,
activation of a cabin switch shifted the spacecraft to a two point
suspension with its front end forward and some 35 degrees
above horizontal. When Grissom hit the switch the spacecraft
dropped into place, pitching both men forward against the
capsule, breaking Grissom's faceplate and scratching Young's.
The actual landing was mild by comparison but the parachute,
still attached, dragged the nose of the spacecraft down in the
water. When released, the spacecraft bobbed to the surface.
The plan was for the astronauts to stay in the craft until it was
picked up by the USS Intrepid, Due to the inacurate landing,
however, the crew were picked up by helicopter and taken to
the recovery ship after a flotation collar was fixed in place hv
Navy swimmers.

The Gemini 4 crew were also jolted when their spacecraft
assumed the two point suspension position, but neither
knocked their helmets against anything. The splashdown
occurred 81,4km from the predicted impact point but recovery
helicopters were close by to pick up the astronauts. Fifty-seven
minutes after splashdown the crew were on the deck of the USS
Wasp.

Gemini 5 landed 168.5 km short Of its predicted landing point
due to erroneous information programmed into the on-board
computer from the ground. As with the Gemini 3 and 4 crews,
this crew was picked up by helicopter. They arrived on the deck
of the USS Lake Champlain just over one and a half hours after
splashdown.

After successfully completing the first space rendezvous,
Gemini 6 splashed down 12.9 km from the predicted impact
point in full view of live television beamed from the recovery
ship USS Wasp via satellite transmission. For this mission the
astronauts stayed aboard the capsule until it was hauled aboard
the recovery vessel. The recovery crew greeted the astronauts
with a large banner proclaiming ‘Seasons greetings from
Wasp’. The USS Wasp was in action again only two days later
when Gemini 7 landed 11.8 km from the predicted impact
point. Thirty-two minutes after splashdown the crew were on
the deck of the ship after being'picked up by helicopter. Schirra
and Borman, the commanders of this rendezvous mission had a
small bet on who would splashdown closer to the target point.
After the Gemini 6 landing, Mission Control told Borman of
the computer controlled re-entry procedures used by Schirra
and the result of this information was that Gemini 7 landed 1.1
km closer to the predicted impact point than Gemini 6.
Borman won his bet!

Gemini 8, with astronauts Armstrong and Scott aboard, had
problems in orbit after docking with an Agena target vehicle.
This caused the mission to be terminated earlier than planned
and resulted in a contingency recovery area being used. Aided
by a new on-board computer designed for the Apollo
programme the spacecraft splashed down safely into the sea
1110 km south east of Okinawa in the Pacific. Even before it hit
the water, the capsule was spotted by an HG-54 Rescuemaster
aircraft from Okinawa. Pararescue men parachuted down to
the spacecraft and hooked on a flotation collar forty-five
minutes after landing. The astronauts then exited the
spacecraft and awaited rescue in a life raft. After three hours
the USS Mason , a destroyer, pulled alongside Gemini 8,
fastened a line to the spacecraft and the astronauts climbed the
Jacob’s ladder to be welcomed on deck by the crew. The
recovery forces had reacted to this emergency landing as if it
had been normal.

Stafford and Cernan aboard Gemini 9 splashed down so
close to their recovery ship USS Wasp that they were able to
open the spacecraft’s hatches, relax and even raise their arms
and thumb a ride on the Wasp. The two astronauts stayed in
their spacecraft until it was hoisted onto the ship’s deck fifty-three minutes after splashdown. The splashdown was the most accurate of all Gemini flights - only 0.7 km from the predicted impact point.

Both Gemini 10 and 11 splashed down safely. The crew of
the USS Guadalcanal watched Gemini 10 hit the water and
twenty-seven minutes later welcomed the astronauts on deck.
Gemini 11 also landed close to its prime recovery ship, the USS
Guam, a sea-going platform for helicopters. The astronauts
arrived aboard the ship only twenty-four minutes after
splashdown. Recovery of the astronauts in both cases was by
helicopter.

Gemini 12 astronauts Lovell and Aldrin described their
landing as ‘hard’, but the astronauts and capsule were picked
up safely and were on the deck of the recovery vessel twenty-eight minutes after splashdown. Recovery of this mission was
televised live throughout the USA via the Early Bird
communications satellite.

Apollo

Apollo 7. the first manned mission of the Apollo programme
was next to splashdown, nearly two years after Gemini 12. The
spacecraft landed in the Stable 2 position (upside down) which
was one of the ways the Command Module (CM) could float.
Three righting bags in the nose of the CM were inflated to flip
the spacecraft over, and seven minutes later the spacecraft
became Stable 1. A flotation collar was fixed by Navy frogmen,
thus providing insurance against swamping from water taken
aboard through the open hatch. The three astronauts were
picked up by helicopter and taken to the prime recovery ship
the USS Essex. Unlike the Mercury and Gemini spacecraft.
Apollo landed with three parachutes, each having a diameter
of 25.3 m. Landing speed was 8.5 m/sec.

After Man's first trip to the vicinity of the Moon. Apollo 8
landed Stable 2 close to its predicted impact point only 11
seconds earlier than the time given in the Flight Plan.
Splashdown came 30 minutes before dawn and the crew
decided to remain in the CM until sunrise. A helicopter than
trasferred the astronauts to the USS Yorktown.

A storm in the selected landing area for Apollo 9 forced
Mission Control to move the landing area 86 km to the south. However, the spacecraft splashed down only 4.8km from the USS Guadalcanal,the prime recovery ship. The only accident
during recovery operations was when the downdraft from a
recovery helicopter overturned one of the life rafts. Apollo 9
was the last American spacecraft to splash down in the Atlantic
Ocean.

Dawn was just breaking when Apollo 10 floated down
to a faultless splashdown 635 km east of Pago Pago in the
Pacific. The three astronauts were on the recovery carrier only
39 minutes after landing and the spacecraft arrived on hoard
one hour later.

The crew of the first moon landing mission,Apollo 11.landed Stable 2 within 24 km of the USS Hornet on 24 July 1969.
The CM,Columbia, righted itself with the aid of the three big
flotation bags after eight minutes enabling Navy frogmen to
attach the flotation collar. On completion of this task all but
one of the frogmen withdrew to a raft 30m upwind of the
spacecraft. The remaining swimmer. Lieutenant Clancy
Hatleberg,opened the CM hatch and passed in three Biological
Isolation Garments for the crew. As the astronauts were
waiting in the CM Collins announced “our condition is
excellent". One hour after splashdown the crew were winched
one by one into a hovering helicopter and after a three minute
flight reached the l/SS Hornet. The three astronauts entered
the Mobile Quarantine Facility (MQFj and from there were
able to speak to President Nixon aboard the recovery ship. This
was the first time a returning crew had been greeted in person
by a President.

Television viewers saw a 6m high splash when Apollo 12
splashed down in a choppy Pacific Ocean on 24 November
1969. The spacecraft hit hard, landing Stable 2. Once the craft
was righted Conrad radioed the recovery forces, reporting
"we're in fine shape". Before the landing, television viewers
were able to see what appeared to be smoke billowing from the
CM. This was actually RCS propellent being vented, an
operation usually performed at a higher altitude. Once the
flotation collar was attached the crew were transferred to the
USS Hornet by helicopter. One hour after splashdown the
astronauts were in the MQF, above which a sign proclaimed
"Three more like before", a reference to the fact that Hornet
had picked up the Apollo 11 crew.

Of all the American spacecraft landings one of the most publicised was that of Apollo 13. the lunar mission which was
terminated early in the flight due. to an explosion in the
spacecraft's oxygen tanks. British Forces joined in the recovery
operations when R.A.F. Command brought its worldwide
Shackleton search and rescue reconnaissance aircraft to a state
of readiness to help the American authorities. Also, six Royal
Navy ships ( Nubian. Phoebe. Vidal. Tideflow. Ennerdale and
Tarbatness) sailed to the spacecraft’s standby splashdown area
in the Indian Ocean 259km east of Mauritius. Two Soviet
merchant ships (Akademician Rykachev and Novopolotsk)
diverted to the prime splashdown area in the Pacific and Soviet
trawlers and whaling ships were ordered to give all possible
help in the recovery of Apollo 13. The splashdown came on 17
April 1970 only 6.5 km from the recovery carrier the USS two
Jima. the spacecraft landing Stable I. Within three minutes a
helicopter was overhead and Navy frogmen dropped into the
sea to fit the flotation collar. The tension of the four day flight
was broken for the astronauts by the first man they spoke to
after splashdown. Navy frogman Ernest Jahnche. who opened
the spacecraft hatch and told Swigert that an Internal Revenue
Service agent was waiting aboard the recovery ship to see him.
He was referring to Swigert's failure to file an income tax return
before the launch! Forty-six minutes after splashdown the
astronauts arrived by helicopter on the deck of the recovery
carrier, a scene watched by millions of television viewers
worldwide.

When Apollo 14 splashed down 1448 km south of Samoa on 9
February 1971 a line from the main parachute failed to detach
and became entangled around the CM as it bobbed in a slight
swell. Navy frogmen, however, cut it free and attached a sea
anchor and flotation collar. Shepard, the commander,
announced that "we’re in very good shape in here" and within a
few minutes the crew were in a life raft awaiting helicopter
pickup.

Apollo 15 landed with only two of its main parachutes at a
speed of 9.5 m/sec compared to the normal 8.5 m/sec with three
parachutes. Despite this harder-than-usual splashdown
astronaut Scott reported "everyone's in fine shape". The CM
submerged briefly and then bobbed up in the Stable 1 position.
The astronauts were soon picked up by helicopter and taken to
the USS Okinawa. NASA narrowed the parachute failure down to two possible faults. Firstly, and the most likely reason,routine expulsion of RCS fuel by the CM as it came down may
have caused contamination of the parachute. Secondly, flaws
were detected in steel harness links on the one parachute
recovered .from Apollo 15. A new metal was used on later
missions.

Casper, the Apollo 16 CM landed only 0.5 km from its predicted impact point to become the most accurate
splashdown of the American manned spaceflight programme.
The CM landed Stable 2, the fifth Apollo to do so, a position
it remained in for four minutes. This was partly due to the fact
that it was dragged by its three main parachutes after it hit the
water. The three large flotation bags were inflated and this
changed the buoyancy characteristics and righted the bobbing
craft. The commander, John Young, radioed "we finally got
this thing right side up and we're doing fine. The condition of
the astronauts is outstanding, it's super". After splashdown,
ten frogmen were in the water when usually only three or four
are involved in this procedure. The reason — to retrieve the
three main parachutes to allow scientists to inspect them for
any clue to the Apollo 15 parachute failure. Forty-five mir.utes
after splashdown the astronauts were on the recovery carrier.

The splashdown and recovery of Apollo 17. the final Apollo
mission was flawless. The CM splashed down gently into calm
seas only 6.4 km from the recovery carrier, the USS
Ticonderoga. The accuracy of the splashdown enabled one of
the recovery helicopters to position itself directly over the
descending spacecraft during the last few metres before
impact. The three astronauts were aboard the Ticonderoga 53
minutes after splashdown.

Skylab

When Skylab 2 returned to Earth after a 28 day stay in space,
the three astronauts remained inside the CM until it was
hoisted aboard the recovery carrier, the USS Ticonderoga.
This was the first time this had happened since Gemini 9 in June 1966 and the reason for this procedure was to protect samples and experimental data onboard the CM from the warm moist
sea air. Also, many doctors felt that after a long period of
weightlessness the crew might not have been able to exit the
CM safely for a helicopter pickup. Swimmers dropped from a
helicopter with flotation gear as in the past but then the aircraft
carrier itself manoeuvred up close to the capsule and hoisted it
aboard. When the astronauts emerged from the spacecraft 40
minutes after splashdown onto the deck of the recovery ship
they appeared unsteady but well.

Skylab 3 landed in the roughest sea encountered by
returning astronauts. The spacecraft landed Stable 2 and even when the three flotation bags righted the spacecraft it nearly tipped over as Navy frogmen tried to secure the flotation collar.
Despite the 2.4m high waves the flotation collar was fixed in
position and the CM was then winched aboard the USS New
Orleans, only 40 minutes after splashdown. Three minutes
later the astronauts emerged from the CM. slightly unsteady,
and were assisted by doctors as they were taken off for medical
examinations.

The final Skylab mission, Skylab 4. also landed Stable 2.
within 5 km of the IJSS New Orleans. Minutes before
splashdown the crew had been warned to wear oxygen masks
because of fears of toxic fumes seeping into the capsule from a
thruster jet which began leaking as they started their return to
Earth. The CM remained Stable 2 for five minutes as the
flotation bags were inflated to right the craft. Within an hour
the spacecraft was on the deck of the recovery carrier and as
with Skylab 3. the astronauts had to be helped across the deck.
This was the first splashdown since 1966 that had not been
covered on live television. The television networks decided
against live coverage because of public apathy!

ASTP

The landing of the last American Apollo spacecraft, the
Apollo used during the joint Soviet-American mission, nearly
ended in disaster. Following reentry, the Earth Landing
System (ELS) was not activated. One of the ELS functions was
to cut off the roll thrusters, used to provide roll stabilisation of
the spacecraft during reentry', and so the RCS system was kept
operating for a longer period than normal, causing the CM to
oscillate during parachute descent. Stafford, the commander,
noticed the thrusters firing and so.cut off the propellent flow.
However, nitrogen tetroxide fumes continued to enter the
cabin through the pressure relief assembly which equalised the
pressures inside and outside of the spacecraft. As the ELS had
not been activated the main parachutes had to be deployed
manually, this being the first time that had happened. During
the last four minutes of descent the three astronauts were
hardly able to breathe due to the fumes and. because of a great
deal of aerodynamic noise and communictions interference.
Mission Control and the recovery forces were unaware of what was happening. The CM "hit the water like a ton of bricks"
(Stafford later-said that the splashdown reminded him of
Gemini 9) and capsized when some of the parachute shrouds
caught on the CM's nose. As the spacecraft was Stable 2
Stafford struggled to get at the oxygen masks located behind
the astronauts couches. Brand, meanwhile, had passed out and
had to be revived with oxygen. Once the CM righted itself
Stafford radioed "We're okay now. We are in Stable 1
position". He then opened the hatch slightly to let some fresh
air in before Navy frogmen reached the craft. A flotation collar
was soon in place and recovery was in Skylab fashion with the
CM being winched aboard the USS New Orleans only 45
minutes after splashdown. All three astronauts had been
affected by the nitrogen tetroxide fumes and were hospitalised
for two weeks in Honolulu.