NASA’S UNMANNED ANTARES ROCKET – BLOWN UP JUST AFTER LIFTOFF – BIG BLOW TO NASA
Transcript
1. NASAS UNMANNED ANTARES ROCKET BLOWN UP JUST AFTER LIFTOFF
BIG BLOW TO NASA
2. INTRODUCTION Antares, known during early development as
Taurus II, is an expendable launch system developed by Orbital
Sciences Corporation. Able to launch payloads heavier than 5,000 kg
(11,000 lb) into low-Earth orbit, it made its inaugural flight on
April 21, 2013. Designed to launch the Cygnus spacecraft to the
International Space Station as part of NASA's COTS and CRS
programs, Antares is the largest rocket operated by Orbital
Sciences. NASA awarded Orbital a Commercial Orbital Transportation
Services (COTS) Space Act Agreement (SAA) in 2008 to demonstrate
delivery of cargo to the International Space Station. For these
COTS missions Orbital intends to use Antares to launch its Cygnus
spacecraft. In addition, Antares will compete for small-to-medium
missions. Antares made four successful launches to orbit in its
first five attempts. On October 28, 2014, an Antares rocket
exploded just after liftoff, completely destroying the vehicle and
damaging launch pad 0 at the Mid-Atlantic Regional Spaceport. A
range-safety officerreported having observed clear signs that the
launch was in trouble, and effected planned destruction of the
mission.
3. DESIGN The first stage uses RP-1 (kerosene) and liquid
oxygen (LOX) as propellants, powering twoAerojet AJ26 engines,
which are modified Soviet-built NK-33 engines. Together they
produce 3,265 kilonewtons (734,000 lbf) of thrust at sea level and
3,630 kN (816,100 lbf) in vacuum. As Orbital has little experience
with large liquid stages and LOX propellant, some of the Antares
first stage work was contracted to the Ukrainian Yuzhnoye SDO,
designers of theZenit series. The second stage is a solid-fuel
rocket, the Castor 30. Developed by ATK as a derivative of the
Castor 120 solid stage, the Castor 30B produces 293.4 kN (65,960
lbf) average and 395.7 kN (88,960 lbf) maximum thrust, and uses
electromechanical thrust vectorcontrol. Antares' Castor 30 solid
stage was based on the Castor 120 solid motor used as Minotaur-C's
first stage.
4. WHY NASA BLEW UP ANTARE Every time NASA launches a rocket,
two safety officers have one weighty decision: They have to decide
whether to push a self-destruct button if it appears the launch is
going awry. If they make the wrong call either way, bad things can
happen. Destroy a rocket prematurely, and millions of dollars in
equipment and research go up in flames unnecessarily. Allow a
malfunctioning rocket to continue, and the lives of people near the
launch site could be at risk. Tuesday night, I saw what happens
when they make the right call. A 139-foot-tall (43 meters) Antares
rocket malfunctioned shortly after takeoff, and was destroyed in a
massive explosion at the launch site after safety officers sent a
kill signal. The glow from the accident was visible for miles up
and down the coast, but because of the safeguards in place, no one
was injured.
5. CONTD The flight safety officer and the range safety officer
are tasked with deciding whether a rocket is operating properly and
either disabling it for safety reasons or letting it proceed. There
can be just seconds to decide, and there is no instant replay. For
reasons still being investigated, the rocket started behaving
erratically and exploded in a mountain of flame and smoke. This
inferno burned across an otherwise picturesque post-sunset sky,
accented high above the horizon to my right by a sliver of a
crescent moon. The explosion happened after safety officers,
watching for any of ten specified problems, such as a gross
deviation from the flight path, sent a signal from the flight
termination system to disable the rocket, although damage from the
malfunction may have already doomed it to collapse back to
Earth.
6. Even a successful launch produces an incredible amount of
smoke and fire as the thrust pushes a 652,000-pound
(296,000-kilogram) rocket out of the atmosphere. In this failed
launch, fuel that was meant to burn off gradually instead exploded
in a ferocious fireball. Spirals of flame fanned out from the
launchpad in all directions as the controlled burn gave way to
chaos. As the overpressure pushed out from the launchpad, I could
feel the explosion as well as see it. Elsewhere, the same shock
wave knocked two spectators off the bed of their pickup truck and
another off her dock. The blast broke windows and imploded doors in
buildings close to the launch site.