This allows a user to connect to one FTP server, then ask that files be sent to a third-party server. Simply it asks the FTP server to send a file to each interesting port of a target host in turn. The error message will describe whether the port is open or not. This is a good way to bypass firewalls, because organizational FTP servers are often placed where they have more access to other internal hosts than any old Internet host would. It takes an argument of the form <username>:<password>@<server>:<port>. <Server> is the name or IP address of a vulnerable FTP server.
A first possible root cause of the failed deployment of the parachutes was announced in an October 14 press release. Lockheed Martin had built the system with an acceleration sensor's internal mechanisms wrongly oriented (a G-switch was installed backwards), and design reviews had not caught the mistake. The intended design was to make an electrical contact inside the sensor at 3 g (29 m/s²), maintaining it through the maximum expected 30 g (290 m/s²), and breaking the contact again at 3 g to start the parachute release sequence. Instead, no contact was ever made.