RocketSTEM Issue #12 - July 2015 | Page 58

Seconds after liftoff, the ORB-3 Antares rocket fell near the launch pad due to an apparent failure in the turbopump supplying fuel to one of the two first-stage engines. Range Safety Officers engaged the Flight Termination System to stop the remaining engine. Credit: Elliot Severn Behind the scenes of launch control By Tony Rice Space flight is dangerous and not just for the astronauts. Over the hundred plus years of rocket technology and space flight growth, many have died just working on rockets or even testing them, from engineers to flight pad crew to even spectators. Progress comes with a price and with that, measures have been taken and improved over the years to try and prevent such events from happening again. With all the advancements we’ve made, launching rockets is still a risky business. We were reminded of this on Oct. 28, 2014 when Orbital Science’s third resupply flight to the International Space Station came to a fiery end moments after liftoff. The first fifteen seconds of the launch was uneventful before one of the two Aerojet Rocketdyne AJ26 engines in the Antares rocket’s first stage failed, robbing the thirteen story tall Antares rocket of the thrust needed to overcome Earth’s gravity. Early analysis of telemetry points to a failure in the turbopump providing fuel to the engine 56 56 according to a statement released by Orbital days after the accident. Along with the Antares rocket, a Cygnus spacecraft carrying 2,215 kg (4,883 lbs) of cargo for the astronauts aboard the ISS was lost. This included crew supplies (food and clothing), another third included spare parts for equipment aboard the station, and the remainder was science experiments. Among those experiments were some created by students from around the United States and Canada participating in the Student Spaceflight Experiments Program (SSEP). These fourth graders though undergraduate students were studying everything from creating soil for growing food in space to muscle development in microgravity. That’s the bad news. The good news is that only property was damaged or lost. No one was injured because the Range Safety System and the people who run it did their job. Each launch site has a range safety system designed to protect people and property both near the site and under the path the rocket overflies known as downrange. Launches from the Wallops Flight Facility in Virginia are monitored from the launch site itself as well as another site on North Carolina’s Outer Banks not far from where the Wright Brothers first took flight over 100 years ago. That second view of the rocket’s path allows controllers to better monitor the vehicle without interference from the rocket’s plume. As the flight continues, tracking stations further downrange in Bermuda or the Bahamas take over providing a continuous view as the rocket heads to orbit. Spacecraft and the rockets that carry them are relatively fragile. Overcoming Earth’s gravity isn’t easy. About 90% of a rocket’s weight on the pad is highly explosive fuel. Should a flight go wrong, Range Safety Officers have a very powerful tool available to help protect people and property on the ground: flight termination. Also known as self-destruct, the Flight Termination System www.RocketSTEM .org