Defender (Conventional Fighter)

This article is about the ground support fighter. For other uses, see Defender.
Defender Medium Strike Fighter
Production information
Manufacturer Imstar Aerospace
King Dumont Defense Facility[1]
Mujika Aerospace Technologies[2]
Basantapur Fine Metals Aerospace Range[3]
Equipment Rating
Use Ground Support
Tech Base Inner Sphere
Introduced 2701[4]
Technical specifications
Mass 25 tons
Engine (Type) Imstar-C 150 Turbine
Fuel 480 - 3 tons
Communications System Lassitor 2JA
Targeting Tracking System IMB SYS 3000
Heat Sinks None
Armor Riese Heavy
Crew 1
BV (1.0)
BV (2.0) 259 [5]


The Defender is a Star League era conventional fighter from the Free Worlds League that has spread across the Inner Sphere. During the first Star League, Imstar Aerospace engaged in a massive marketing effort that made the Defender known in every Successor State and Periphery nation. It became so ubiquitous, in fact, that it's also known as the Medium Strike Fighter across the Inner Sphere. A cheaper alternative to expensive aerospace fighters, the Defender and its variants are easy to build with locally produced components.[5]

Weapons and Equipment[edit]

Though an aerospace fighter will probably destroy the Defender fairly quickly in a dogfight, the nose-mounted Irian Weapon Works SRM-2 and wing-mounted LongFire LRM-5 launchers allow the Defender to successfully attack other conventional fighters, VTOLs, and harass ground targets. Though 'Mechs are probably not going to fear the damage inflicted by a single Defender, an entire squadron can quickly cause problems for an arrogant MechWarrior.[5]


The Defender has five external hardpoints which allow it to carry bombs. This is useful when attacking ground defenses or destroying bridges to slow enemy forces.[5]


Due to the popularity of the Defender, it has become the de facto Medium Strike Fighter across the Inner Sphere. It has therefore become the basis for several variants.

  • Steinadler 
    It's name roughly translated as "Golden Eagle", the Setinadler is a Lyran copy of the Defender. BV (2.0)= 226[8]
  • Crane 
    A Capellan variant produced on St. Ives that replaces the SRM with a third LRM-5. All the LRM launchers are connected to a shared ammunition bin. BV (2.0)= 293,[11] 274[12]
  • Defender II 
    Introduced by the Free Worlds League in 3038, this variant replaces the SRM with Artemis IV fire control systems for the LRM launchers. This version, like its forerunner, also became popular across the Inner Sphere.[13] BV (2.0)= 253,[14] 234[15]
  • Drake 
    The Drake Medium Fighter is an Experimental Technology prototype which was constructed by Basantapur Fine Metals of Colorado in 3073. Based on the Defender II variant, this fighter has been heavily modified, now featuring a 210-rated fusion engine. The Drake was given 2 tons of Vehicular Stealth armor and a Guardian ECM Suite, allowing it to be nearly invisible to prey. The ship has also been given Modular Armor on all of its sections. The Modular Armor adds more protection to the ship, but slows it down until ejected from the ship. The ship's main weaponry include a pair of nose-mounted MML-3 Launchers with two tons of ammo. Serving as a backup weapon, the ship has a single ER Small Laser. BV (2.0) = 452[18]
  • Drake Medium Stealth Fighter 
    This production version of the Drake changes the weapons and armor extensively. Though it uses Vehicular Stealth armor and a Guardian ECM system like its progenitor, the Modular Armor and ER Small Laser have been removed. In their place is a light autocannon/5 and a ton of ammunition. The MML-3 of the prototype Drake also remains. Between the LRMs that can be fired from the missiles and the reach of the Light AC, the Drake Stealth Fighter offers a great deal of long range punch. It has become a popular fighter with most Federated Suns militia units. BV (2.0) = 389[19][20]

Design Quirks[edit]

The Drake Medium Stealth Fighter custom variant is subject to the following Design Quirks:[19]

Related Designs[edit]



  1. Objectives: Periphery, p. 31
  2. Objectives: Capellan Confederation, p. 23
  3. Objectives: Federated Suns, p. 13
  4. MUL online date for Defender (Conventional Fighter)
  5. 5.0 5.1 5.2 5.3 Technical Readout: 3039, pp. 180–181: "Defender Fighter Profile"
  6. Record Sheets: 3039, p. 208
  7. Record Sheets: 3039 Unabridged, p. 283
  8. Record Sheets: 3039 Unabridged, p. 286
  9. Record Sheets: 3039, p. 209
  10. Record Sheets: 3039 Unabridged, p. 285
  11. Record Sheets: 3039, p. 206
  12. Record Sheets: 3039 Unabridged, p. 282
  13. Objectives: Federated Suns, p. 28: "Jalastar Aerospace"
  14. Record Sheets: 3039, p. 207
  15. Record Sheets: 3039 Unabridged, p. 284
  16. Technical Readout: 3150, p. 224
  17. Record Sheets: 3150
  18. Experimental Technical Readout: Boondocks p. 14
  19. 19.0 19.1 Technical Readout: Prototypes, p. 159
  20. Record Sheets: Prototypes, p. 79