Rocket Lab called off a launch attempt Tuesday, U.S. time, in New Zealand after encountering a technical problem during the countdown for the company’s first commercial satellite launch. Tuesday’s countdown came after a four-day delay to resolve problems with a downrange tracking station and wait for improved weather.

Commercial ziplines have been installed and tested at United Launch Alliance’s Atlas 5 rocket pad as the emergency escape system if astronauts and ground personnel need to evacuate the Crew Access Tower.

A European Vega rocket deployed six commercial satellites in orbit, including a new Airbus-built eye-in-the-sky for high-resolution Earth-imaging, on a successful launch from French Guiana on Wednesday night after two of the last three Vega missions failed.