| From: [email protected]
Newsgroups: clari.tw.space,clari.news.features
Subject: Challenger remembered
Date: 22 Jan 91 21:36:37 GMT
_U_P_I_ _S_C_I_E_N_C_E
_N_A_S_A_ _s_t_a_n_d_s_
_a_t_ _c_r_o_s_s_r_o_a_d_s
_f_i_v_e_ _y_e_a_r_s_
_a_f_t_e_r_ _C_h_a_l_l_e_n_g_e_r
_B_y_ _W_I_L_L_I_A_M_
_H_A_R_W_O_O_D
_U_P_I_
_S_c_i_e_n_c_e_ _W_r_i_t_e_r
CAPE CANAVERAL, Fla. (UPI) -- Five years ago Monday, the space shuttle
Challenger exploded 73 seconds after liftoff in a disaster rivaling the
sinking of the Titanic as a symbol of tragedy and misplaced trust in the
infallibility of technology.
Today, the shuttle program is back in action with 13 successful post-
Challenger missions on the books and plans for seven more in 1991.
Despite its success, however, the National Aeronautics and Space
Administration stands at a new crossroads. Its planned space station is
in jeopardy and there is no firm political support for a return to the
moon or a manned mission to Mars.
A White House report on NASA's future, citing the potential for
another Challenger-like disaster, recommended using new, unmanned
rockets to carry payloads into orbit that do not require the services of
astronauts.
Put simply, the report said the nation should not risk $2 billion
space shuttles and human lives to launch garden-variety satellites.
Commercial satellites were banned from the shuttle after the Challenger
accident and military payloads are being switched to unmanned Air Force
Titan 4 rockets.
So despite having recovered from the devastation of the Challenger
disaster and correcting the problems that caused it, a deeper problems
remains: Defining a clear mission for the nation's manned space program.
On the surface, the picture seemed much clearer in 1986 when
Challenger rocketed away on what was to have been the second of 15
shuttle flights, a voyage to place a $100 million NASA communications
satellite into orbit.
``All right!'' astronaut Judith Resnik said as the black-and-white
space freighter thundered away from the Kennedy Space Center after a
string of frustrating delays.
``Here we go,'' added co-pilot Michael Smith just one second after
the ship's twin solid-fuel boosters ignited with a ground-shaking roar
to kick off the 25th shuttle mission.
It was 11:38 a.m. EST on Jan. 28, 1986. Unknown to Challenger's
seven-member crew, jets of hot gas were swirling through a critical
joint holding two sections of the shuttle's towering right-side booster
together, eating through the wall of the rocket like a 5,000-degree blow
torch.
Telltale puffs of black smoke shooting from the flawed joint went
unnoticed, disappearing a few seconds later as the sooty remains of
charred rubber O-ring seals, grease and other debris apparently lodged
in the joint, temporarily staunching the fatal breach.
On board were Smith, Resnik, commander Francis ``Dick'' Scobee,
Ellison Onizuka, Ronald McNair, civilian satellite engineer Gregory
Jarvis and New Hampshire high school teacher Christa McAuliffe, the
first private citizen to win a seat on a space shuttle.
``Go you mother,'' Smith said into the ship's intercom 11 seconds
after liftoff as Challenger wheeled about to line up on the proper
trajectory. Despite a frigid night and trouble with ground equipment,
all systems finally appeared to be ``go'' for flight.
But the shuttle was buffeted by higher-than-normal winds aloft and as
the ship thundered past the speed of sound and the region of maximum
aerodynamic pressure, the weakened booster joint finally gave way once
and for all just under one minute into the flight. The crew remained
unaware of anything amiss.
``Feel that mother go,'' Smith said over the ship's intercom as the
shuttle rocketed toward orbit.
It was exactly 11:39 a.m. and Challenger was 13 seconds away from
destruction.
At 64.660 seconds into the flight, the jet of flame from the booster
O-ring joint ``burn through'' ate through the thin skin of the shuttle's
external fuel tank. Two seconds after that, pressure in the tank began
to drop as liquid hydrogen spewed out through the ever enlarging hole.
``Challenger, go at throttle up,'' astronaut Richard Covey radioed
from mission control in Houston, telling the crew that Challenger's
engines were running properly at full power.
``Roger, go at throttle up,'' Scobee calmly replied.
Two seconds later, the jet of flame from the booster rupture burned
through a strut holding the base of the rocket to the external tank. The
bottom of the 14-story booster then pulled away, causing the nose to
rotate into the top of the fuel tank, spilling a cloud of liquid oxygen
into the sky.
Less than one second after that, the bottom of the tank gave way and
the shuttle disappeared in a conflagration as propellants mixed and
burned in the upper reaches of the atmosphere.
``Uh oh,'' Smith said over the intercom in the crew's last recorded
utterance. A moment later, the astronauts were subjected to a bone-
jarring but survivable jolt as the ship's nose section ripped away and
arced through the frigid sky 48,000 feet above Cape Canaveral.
For an instant, the astronauts must have heard, or felt, the violent
metal-on-metal rip as the fuselage tore away behind them. Scobee may
have tried to radio mission control out of reflex, but the shuttle's
crew module no longer had electrical power.
Back at the space center, McAuliffe's shocked family and relatives of
the other astronauts watched in horror as billowing streams of smoke-
trailing wreckage arced away from the still-ballooning cloud, plummeting
to the ocean below.
``Flight controllers here are looking very carefully at the
situation,'' said NASA commentator Steven Nesbitt in Houston.
``Obviously a major malfunction.''
A few seconds later Nesbitt confirmed the worst fears of thousands of
spectators: ``We have a report from the flight dynamics officer that the
vehicle has exploded.''
Inside Challenger's crew module the instruments were dead, the lights
were out and it must have been eerily quiet with the crackling roar of
the solids, the dull throbbing of the main engines suddenly and forever
gone.
At least some of the shuttle fliers apparently activated emergency
air supplies after the initial breakup of the orbiter, but it is not
known how long they remained conscious as the crew module shot up to 65,
000 feet before arcing over and plunging back to Earth.
Finally, less than 3 minutes after the explosion, the crew cabin
slammed into the Atlantic Ocean in a steep left bank at more than 200
mph, instantly killing any of the seven shuttle fliers who might have
been alive.
Like the sinking of the Titanic, Challenger's destruction on that
cold January day will be remembered for decades as an icon of disaster,
the worst accident in the history of the space program and one that has
come to symbolize the fallibility of America's vaunted high technology.
And like the aftermath of the Titanic disaster, Challenger's demise
prompted sweeping changes to improve safety, changes that grounded
NASA's shuttle fleet for nearly three years but left America with a
safer if less adventurous space program.
------
On Feb. 3, 1986, 13 members of a presidential commission were named
to investigate the Challenger disaster.
The panel was chaired by former Secretary of State William Rogers and
featured moon walker Neil Armstrong, shuttle flier Sally Ride and Nobel
laureate Richard Feynman among its distinguished members.
The primary cause of the disaster was quickly traced to the failure
of the O-ring joint between two fuel segments in Challenger's right-side
solid propellant booster rocket. But the panel determined more than a
technical fix was needed to put NASA back on track.
The turning point in the investigation came when the Rogers
Commission learned of a launch-eve debate between NASA and engineers
with booster-maker Morton Thiokol Inc., now called Thiokol Corp.
Because of concern about the effects of freezing temperature on the
sensitive rubber O-ring seals in the booster joints, Thiokol engineers
set up a teleconference with NASA program managers the night before
launch and unanimously recommended a launch delay.
But NASA engineers in charge of the booster project at the Marshall
Space Flight Center in Huntsville, Ala., challenged the recommendation
and pressured Thiokol to prove the joints were not safe to fly. Thiokol
ultimately gave in and reversed the no-launch recommendation.
It was a stunning revelation, prompting Rogers to issue a statement
Feb. 15 saying NASA's decision-making appeared to be flawed and that
anyone involved with the decision to launch Challenger was barred from
the accident investigation.
Finally, on June 9, the commission presented its findings to
President Reagan.
The panel made nine recommendations in its 256-page report, the first
calling for a redesign of the faulty booster joints. But the panel
members went much further than simply criticizing the booster design.
They called for -- and got -- independent oversight of NASA operations
and a review of management procedures with an emphasis on getting
astronauts involved in actually running the agency.
Today, former astronauts hold three of NASA's top positions with
veteran shuttle skipper Richard Truly serving as the space agency's
administrator.
The commission also called for -- and got -- improved communications, a
rudimentary crew escape system and improved shuttle landing systems and
a commitment by NASA to limit launch rates to achievable levels while
increasing crew training time.
Along with the booster failure, the commission said pressure to meet
an overly ambitious launch rate was a contributing cause of the disaster
as was a ``silent safety program'' that allowed the continuation of
shuttle launches despite the history of O-ring problems. Virtually all
of the panel's recommendations were implemented.
_a_d_v_ _w_e_e_k_e_n_d_
_j_a_n_ _2_6_-_2_7_ _o_r_
_t_h_e_r_e_a_f_t_e_r
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| From: [email protected] (WILLIAM HARWOOD, UPI Science Writer)
Newsgroups: clari.tw.space,clari.news.aviation,clari.news.top
Subject: Challenger astronauts remembered
Date: 28 Jan 91 18:11:40 GMT
NASA workers observed 73 seconds of silence to honor the five
astronauts and two civilians who perished aboard the space shuttle
Challenger five years ago Monday in history's worst space disaster.
Challenger blasted off on its 73-second voyage into history at
11:38 a.m. EST on Jan. 28, 1986. It was the 25th mission in the history
of the shuttle program, the second of 15 planned for that year.
On board were commander Francis ``Dick'' Scobee, co-pilot
Michael Smith, Ellison Onizuka, Ronald McNair, Judith Resnik, civilian
satellite engineer Gregory Jarvis and New Hampshire high school
teacher Christa McAuliffe.
The shuttle was destroyed by the rupture of a faulty
solid-fueled booster, grounding America's manned space program for
more than two years and prompting sweeping changes to minimize the
possibility of another such tragedy.
``Today marks the day that we in the NASA family remember
the seven astronauts who flew aboard Challenger,'' said agency
Administrator Richard Truly. ``We will never forget them.''
Looking to the future, more than 1 million students were
expected to participate in a nationwide teleconference about Earth's
environment that was beamed into their schools by the Challenger
Center, an Alexandria, Va., organization founded by relatives of the
fallen astronauts that is dedicated to space science education.
``I don't like to dwell on the past so I think that bitterness
is something that's behind us and I think it's better to look forward
to the future,'' Charles Resnik, brother of the Challenger astronaut,
said in an interview with Challenger center officials.
``That's a whole lot easier. Perhaps there is a silver lining
to the cloud that was created five years ago and that silver lining is
the Challenger Center.''
At 11:38 a.m. Monday, NASA workers and contractors at the
Kennedy Space Center and other agency facilities observed 73 seconds
of silence as they have every year since Challenger flew to its doom
to honor the memory of the ship's fallen crew.
Flags were lowered to half staff and workers at the sprawling
base were ordered to observe radio silence for the duration of the
low-key remembrance.
``As we have done in the past four years, we pause 73 seconds
in honor of the astronauts, the crew of Challenger,'' Kennedy Space
Center Director Forrest McCartney said in a televised address. ``It is
appropriate that we do that again this year.
``So won't you join me in a 73-second pause, during which time
we can remember and honor the crew of Challenger and at the same time
recommit ourselves to excellence in everything we do.''
In McAuliffe's hometown of Concord, N.H., city officials
planned no special ceremony to mark the fifth anniversary of the
disaster other than a moment of silence at Concord High School, the
last such remembrance now planned.
Principal Charles Foley said the school district prefers ``to
stress the positive aspects of McAuliffe's life rather than the tragedy.''
Challenger was destroyed after 5,000-degree flame ate through
an O-ring joint in the ship's right-side solid-fuel booster, creating
a deadly, out-of-control blowtorch that burned through the skin of the
shuttle's external fuel tank and triggered the aerodynamic
disintegration of the $2 billion orbiter.
Contrary to popular accounts, Challenger did not explode. What
appeared to be an explosion high above Cape Canaveral that cold
January day was the fast burning of its load of liquid propellant as
the tank collapsed. The shuttle itself, however, was torn apart by
aerodynamic forces.
``Uh oh,'' Smith said in the crew's last recorded utterance as
the shuttle began breaking apart, subjecting the astronauts to a bone-
jarring but survivable jolt as the ship's nose section ripped away and
arced through the frigid sky 48,000 feet above Cape Canaveral.
At least some of the shuttle fliers apparently survived the
initial breakup of the orbiter, activating unpressurized emergency air
supplies in a desperate bid for survival.
But it is not known how long they may have remained conscious
as the crew module shot up to 65,000 feet before arcing over for a
terrifying plunge to Earth.
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