Monday, November 03, 2014

Orbital Sciences and Virgin Galactic Sift Through Their Wreckage

          by Brian Orlotti

Antares rocket. Graphic c/o OSC.
The NewSpace industry was dealt two hard blows this past week with two accidents (one of them deadly), which have triggered criticism from some media outlets on the merits of commercial space travel.

Here's what we know.

On Oct 28th, an Antares rocket built by Orbital Sciences Corporation (OSC) exploded about 15 seconds after liftoff from NASA's Wallops Flight Facility on Wallops Island, Virginia. The Antares vehicle was carrying a Cygnus automated cargo spacecraft (also built by OSC) on what would have been Orb-3, the third of eight resupply flights to the International Space Station (ISS) under OSC's Commercial Resupply Services contract with NASA.

Initial flight data analysis by OSC indicated that all systems functioned normally until about 15 seconds after launch, when a failure occurred in the rocket's first stage after which it lost propulsion and fell back to the ground near the launchpad.

Before hitting the ground, the rocket's self-destruct system was triggered by the Wallops Range Control Centre to minimize the spread of hazardous debris as well as to reduce damage to the launch site.

The Antares' first stage is powered by two Soviet-era NK-33 engines designed in the late 1960s and early 1970s by the Kuznetsov Design Bureau and intended for the ill-fated Soviet N-1 moon rocket, a program which ended in failure. The unused engines were eventually purchased from Russia, re-branded and refurbished as the AJ-26 by Aerojet Rocketdyne and had powered four previous successful Antares flights.

However, as outlined in the June 9th, 2014 article, "Caution Prevails - Orbital Antares Launch to the ISS Postponed," earlier in the year an AJ-26 engine scheduled for a 2015 mission failed a hot-fire test. Both AJ-26 engines on the Orb-3 flight had passed their hot-fire tests.

OSC competitors have also commented on OSC's choice of 1960's era engines to power their rockets. Elon Musk, CEO of SpaceX has been the most vocal critic, saying in the October 12th, 2012 Wired Magazine article, "Elon Musk’s Mission to Mars," that:
Elon Musk. Photo c/o Art Streiber.
One of our competitors, Orbital Sciences, has a contract to resupply the International Space Station, and their rocket honestly sounds like the punch line to a joke. 
It uses Russian rocket engines that were made in the ’60s.
I don’t mean their design is from the ’60s—I mean they start with engines that were literally made in the ’60s and, like, packed away in Siberia somewhere...
The OSC crash investigation continues.

The second accident occurred on Oct 31st, when Virgin Galactic's SpaceShipTwo suborbital spaceplane was torn to pieces and crashed, after detaching from the underside of its mothership WhiteKnight Two, while on a test flight over the Mojave desert.

SpaceshipTwo was being flown by two test pilots, Peter Siebold, the director of flight operations at Scaled Composites (the builders of SpaceShipTwo) and co-pilot Michael Alsbury.  Although Alsbury was killed in the crash, Siebold survived and is currently recovering in hospital.

Designed to carry passengers on suborbital flights, SpaceShipTwo is carried to its launch altitude by a carrier aircraft, White Knight Two, where it is released to fly into the upper atmosphere by igniting its rocket engine. On its return, SpaceShipTwo glides back to Earth and performs a conventional runway landing.

SpaceShipTwo. Graphic c/o
Initially, suspicions focused on SpaceShipTwo's innovative new hybrid engine, which uses powdered plastic as fuel and nitrous oxide as an oxidizer, as a cause of the crash.

However, prior to May of this year, SpaceshipTwo had a different engine which used powdered rubber as a fuel. The powdered rubber/nitrous mixture garnered years of controversy after a 2007 accident in which two Scaled Composites employees were killed during an oxidizer flow test at the Mojave Air and Space Port.

The test entailed filling an oxidizer tank with 4,500 kilograms of nitrous oxide, followed by a 15-second cold-flow injector test. During the test, an explosion occurred, killing three employees and injuring three others.

Despite subsequent investigations, no definitive cause for the explosion was ever found.

On Nov 2nd, the US National Transportation Safety Board (NTSB) held a press conference and tweeted the findings of its investigation thus far. Significantly, a review of the cockpit's forward-looking camera shows that the feather (the mechanism around SpaceShipTwo's wings and rear tail assembly that can be raised vertically to act as an air brake) had been unlocked by the copilot just before the craft hit Mach 1.

Normal procedure is to unlock the feather after reaching Mach 1.4 to prevent aerodynamic forces from extending it prematurely. The NTSB investigation is likely to continue on for some time.

Media reaction to the two accidents has ranged from the thoughtful and pragmatic, such as the November 1st, 2014 CNN article, "Deadly day for space tourism -- but future 'rests' on such days, official says," to the ignorant and short-sighted, as epitomized in the October 31st, 2014 Wired article, "Space Tourism Isn't Worth Dying For."

The common thread in the criticism of commercial spaceflight is the supposed pointless waste of lives for the sake of a pastime for the wealthy.

All new frontiers come with their own set of perils, and space is no exception. Commercial spaceflight seeks to overcome those perils, taking the first steps toward humans living and working in space. The global aviation industry we rely on today was built on the risks taken and lessons learned from the Wright Brothers, Charles Lindbergh, Howard Hughes and countless test pilots.

NewSpace also owes much to the sacrifices of astronauts in the Apollo program and the crews of the space shuttles Challenger and Columbia. Risk and sacrifice are what open new frontiers and move societies forward.

Brian Orlotti.
Certainly its important to pause for a moment and figure out what happened last week with the Antares rocket and SpaceShipTwo.

But when we've figured it out, lets get back out there and resume our boldly going. 

Brian Orlotti is a Toronto-based IT professional and a regular contributor to the Commercial Space blog.

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