Sevencyclopaedia - D

DETECTORS

Sometimes referred to as sensors or scanners. Various detection instruments were carried by Liberator, operating at different ranges. The extra-range detector was said by Cally to put a heavy drain on the energy banks in The Keeper. Other references to detectors are:

• Duel: Travis used the body of UP-Duel as a screen against Liberator's detectors. Jenna also referred to this (not-unlikely) limitation on detectors in Killer.
• Volcano: the approaching Federation cruisers were picked up by the medium range detectors, despite Cally telling Vila to keep an eye on the long range detectors earlier in the episode. This suggests that detectors were by no means reliable (as one might expect). Zen later scanned the surface of Obsidian for signs of a weapon having been fired - this might indicate the sensitivity of on-board detectors, or simply be a case of Avon trying a long shot.
• Dawn of the Gods: visual detectors were stated as having a long-range intensifier. Scans were made at ranges of up to 20 million spacials, far further than anywhere else in the series.

Few details were given as to how the various detector systems worked, but Blake mentioned etheric detector beams in Cygnus Alpha. When the aft scanners were used to scrutinise Wanderer K47, Jenna noted that the "spectro says it's ferrous", indicating one capacity of the Liberator's detector systems. Spectro-analysis was mentioned again in Terminal.

In The Harvest of Kairos Tarrant ordered a parallax scan whilst in orbit over UP-Sopron. This revealed a fourth pursuit ship lying in wait for the Liberator.

The command for a "360 orbital scan" was given on a number of occasions, presumably to scan all around the ship in every direction.

Few references were made to Scorpio's detector systems. Main detectors were reduced to 50% operational capacity after an attack by pursuit ships in Animals.

Other ships had detectors as well, of course, and Liberator was first scanned by detector beams at the end of Cygnus Alpha. The pursuit ships changed course "towards this system". A mutoid on Servalan's star cruiser in Volcano reported detecting surface tremors on Obsidian with long-range sensors.

In Trial Blake intended to relocate the homing beacon he took with him down to the Host using a "hand detector". Other hand-held directional devices were seen in various episodes.

A Hand Detector

As for detector range, the course change of the pursuit ships in Cygnus Alpha suggests that detectors could operate over very long, possibly interstellar distances. In The Web it was mentioned that passing pursuit ships could detect the Liberator when they came within two million spacials, and this same range was cited again in Project Avalon. In Hostage, on the other hand, pursuit ship detector range was stated to be just 900 spacials (with the detector shield non-operational). The Federation ships in this episode had detector shields of their own and were first picked up when just 500 spacials away. Later in the episode, Servalan's approach (presumably at Time Distort 10) in C-26 was detected whilst 15 minutes away from landing on Exbar, and Zen stated that it would be 12 minutes before Liberator was in detector range of C-26 - a significant difference in range!

In Mission to Destiny it took Liberator 16.1 minutes to reach the Ortega at Standard by 4: if there was any indication as to how fast SB-4 might be, it would be possible to calculate a lower limit to maximum detector range. In Dawn of the Gods Tarrant commanded detector sweeps at ranges of up to 20 million spacials. The interceptors in The Harvest of Kairos were detected at a range of 8 million spacials. The Federation freighter headed for Horizon was operating minimum scan and could not detect the Liberator at 150 spacials.

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