This aqua-rifle is accurate and powerful, firing hollow steel harpoons from sealed packs of 10. Each harpoon has its own gas reservoir.
Source: Terror From The Deep Ufopaedia
The Jet Harpoon fires a high pressure jet propelled armour piercing harpoon. Like the harpoons used by divers for hunting dangerous sea creatures, the Jet Harpoon has been adapted as X-COM's initial standard underwater rifle. They can be fired in any environment with no loss in power or accuracy.
Like the Dart Gun, the Jet Harpoon is not an especially powerful weapon. It does have twice as much power and is faster and easier to aim than the Dart Gun. It is enhanced with the addition of a three round burst mode.
One of the Jet Harpoon's weaker points is its low ammunition capacity. It only has 10 harpoons. This requires carrying plenty of spare harpoon clips for long sorties.
Jet Harpoons perform adequately against Aquatoids and Deep Ones. However, even Gill Men typically require 3 or 4 hits to fall, and all other aliens are either mostly or completely immune due to the Harpoon's very low damage and mediocre damage type. Fortunately, in the first month those three aliens are the only ones you'll encounter, so Jet Harpoons are a reasonable armament for those Aquanauts not strong enough to carry Gas Cannons or Hydro-Jet Cannons. They should, however, be replaced by more potent weapons such as the Gauss Pistol, Gauss Rifle and Sonic Pistol at the earliest opportunity.
Note that the Harpoon Clip only holds 10 rounds, so bring at least two spare clips if you intend to make any use of the Jet Harpoon's autofire capability.
|Terror From The Deep: Equipment (TFTD)|
|Armor||Diving Suit • Plastic Aqua Armor • Ion Armor • Magnetic Ion Armor|
|Weapons||Dart Gun • Jet Harpoon • Gas Cannon • Hydro-Jet Cannon • Torpedo Launcher • Thermal Tazer|
Magna-Blast Grenade • Particle Disturbance Grenade • Magna-Pack Explosive
|Portable Equipment||Dye Grenade • Particle Disturbance Sensor • Medi-Kit • Chemical-flare • M.C. Disruptor • M.C. Reader • Zrbite|
|SWS||Coelacanth/G. Cannon • Coelacanth/Aqua Jet • Coelacanth/Gauss • Displacer/Sonic • Displacer/PWT|
|Data||Weapon Summaries • TFTD Item destruction table • SWS/Terror Unit Innate Weapons|