Wallops Island, VA -- The first attempt at launching Orbital’s new Antares rocket was canceled with less than 10 minutes on the countdown clock, at around 4:44 PM ET on April 17, 2013. A “premature disconnect” on the rocket’s second stage umbilical cord was reportedly the cause.
Antares was scheduled to make its maiden flight – dubbed “A-ONE Mission” by Orbital – at 5 PM ET today and all launch control calls were in the green when the umbilical disconnected from the rocket, resulting in an immediate abort call and saving of the vehicle.
A white cloud of vapor caused by venting liquid oxygen quickly obscured the bottom of the pad.
Orbital Executive Vice President Frank Culbertson said an Ethernet cable providing two-way communications between the rocket and the launch control center prematurely disconnected, stopping the countdown. Engineers sought an opportunity to examine the individual connecter and the disconnect lanyard for the cable, to figure out why it happened and take corrective action.
Weather conditions earlier in the day put the chances for launch at about 45 percent due to low clouds, but the skies appeared to clear sufficiently to allow a 5 PM launch attempt.
NASA spokespeople said the earliest another launch attempt could take place would be on Friday, April 19, 2013, at 5 PM ET. The weather report for Friday afternoon, however, indicates rain showers during the afternoon with an 80-percent chance of bad weather. Better weather is expected on Saturday and Sunday.
Flight safety rules require relatively clear skies so launch safety officials can observe the rocket as it ascends skyward.
The Orbital Antares is a two-stage rocket: The first stage is based on the Ukrainian Zenit rocket used by Russia and Sea Launch. Unlike the Zenit, the Antares first stage incorporates two liquid oxygen/RP-1 Aerojet AJ-26 engines, which themselves are reworked Russian NK-33 engines built back in the 1970s for the Soviet Moon project.
Antares’ second stage uses an ATK (News - Alert) Castor 30 solid rocket motor.
When A-ONE is finally launched, its primary mission is to take an instrumented “mass simulator” on a 10-minute ride into orbit, gathering data on the flight environment for Orbital’s Cygnus cargo spacecraft. It will also carry a trio of smaller cubesats into orbit, two of them NASA small spacecraft projects built around off-the-shelf Google (News - Alert) Nexus phones.
Orbital has two more Antares launches scheduled for this year – a NASA COTS demonstration flight to prove its Cygnus can successfully rendezvous and berth with ISS, and a NASA CRS contracted supply flight by the end of the year.
The other two flights can’t go forward until the A-ONE mission successfully takes place.
Edited by Braden Becker