ROBOTECH Technical Files
by Pieter Thomassen and Peter Walker, with Robert Morgenstern


Air Defense Robot ADR-04 Defender.

RDF Seal
Southern Cross Seal
REF Seal
Defender Air Defense Robot
Mecha Separator

I. Dimensions:

II. Type:

III. Service History:

IV. Propulsion:

Auxiliary power unit:
Thrusters for space maneuvering (actually fitted only in the Spacy destroids):
(attitude control)

V. Performance:

VI. Electronics:

Radar System:
Optical tracking:
Tactical Electronic Warfare System (TEWS):

VII. Armament:

(ADR-04 Mk. X):
(ADR-04 Mk. XI)
Defender - Rear View

VIII. Armor:

The armor on the Defender is composed of a standard Chobham laminar developed in the late 20th century and improved with the materials science advances made during the Robotech era. This armor was mainly designed to defeat projectiles and other kinetic weapons. The armor stops all small arms and heavy infantry weapons fire, provides excellent resistance to light mecha-mounted weaponry, such as the Zentraedi 22.3mm HE autocannon round, and fair resistance to medium mecha-mounted weaponry, such as the Valkyrie's 55mm APFSDS round.

The Defender provides full protection from nuclear, biological, and chemical hazards, using a sealed cockpit environment activated by radiation and hazardous chemical sensors, or manually when biological warfare conditions are anticipated. The internal consumables supplies can provide atmosphere for three days maximum.

IX. Development:

The ADR-04 Defender series is one of three Destroids that have a Vickers-Chrysler leg assembly in common. This was a design requirement so as to keep development costs down. While the other Earth-decigned Destroid in this series, the MBR-04 Tomahawk, is a main battle robot, the ADR-04 is an air defense robot, intended to either guard important rear area installations, or, by using its comparable mobility, to join the Main Battle Robots on deployments. In the latter cases, the Defender also served as a satisfactory fire support platform, although the armament was unsuited for indirect fire.

Catering to its specialization (close and medium range air defense), the Defender was equipped with a powerful radar system and advanced targeting computer, and with broadband ESM equipment for battle situations in which active radar emissions would not be wise. The system lay-out and integration delivered a fine, capable mecha, but the design process was protracted and expensive, with no less than 9 different versions and prototypes being build (occasionally in parallel) until the production version took shape in late 2008.

As an anti-aircraft mecha, the Defender did a magnificent job, with its extremely effective hypervelocity guns. These relatively large-caliber weapons had a very high muzzle velocity, and thus short flight times and great kinetic energy penetration capabilities, making the shells quite Defender Extended Magazineeffective against airborne mecha. In addition, the rounds were terminally guided by the mecha, using a semi-active laser designator system. Other mecha could also provide terminal guidance, as the standard laser ranger/designator was used, but only if they were in full datalink with the firing Defender. Ammunition restrictions led to two developments, however; firstly a new external drum was developed that increased the capacity by 50% to 150 rounds per gun, and secondly, a new variant was developed with lasers in the arms instead of auto-cannons, and charging capacitors where the ammunition bins had been. This laser Defender, or the "Mark Eleven" as it soon came to be called, was effective in most situations, but was more expensive in both cost and materials to produce, as well as in power consumption, and never saw widespread use, being stationed at vital strategic points rather than on the battle-field. The ADR-04 Mk. X first entered combat squadrons in March 2009. The Mk. XI appeared in mid 2010.

The Destroids based on this undercarriage were among the most important mecha during the First Robotech War and the later Malcontent Uprisings through 2019. Numerous Defenders lumbered on in militias until 2025, and many can still be seen in museums today.

See additional design notes.

Return to UNDF Mecha Index.

Go to Robotech Reference Guide Home Page.

Robotech (R) is the property of Harmony Gold. This document is in no way intended to infringe upon their rights.

Content by Pieter Thomassen and Peter Walker, with Rob Morgenstern
HTML by Robert Morgenstern (
Copyright (c) 2000, 1997, 1995 Robert Morgenstern, Pieter Thomassen, Peter Walker