The Defiant Class of starship was born in what has been called the darkest hour in Starfleet's history, the first Borg incursion and the battle of Wolf 359. Of the 42 ships only none survived the attack. 11,000 lives were lost that day and Starfleet was left in shambles. Fears of a Borg counter strike were still high though and naturally the Defiant continued in Development. However there was a serious problem. The test ship was incapable of performing. In retrospect the test crew were more used to the normal style of starship, and were as such completely unprepared for the 'unusual' habits that the Defiant Class. In the words of Captain Alexander Nassau, commanding officer on the test team, "The Defiant simply put, is a starship squeezed into the shell of a fighter. It is overpowered, over-gunned and is prone to extreme shearing stress when the oversized warpcore is powered to maximum. This ship, when confronted with a battle situation will simply tear itself to pieces, much to the amusement of its foes."
After that damning statement and the testing review, the Defiant was shelved - stored away in pod 13 of Utopia Planitia. The 2 other incomplete chassis were towed to a secure storage facility in orbit on Venus and the Defiant Class was closed.
Three years later, the previous station commander of Utopia Planitia, Commander Sisko, brought the Defiant out of storage. Along with a team of experts including Romulan scientists, the Defiant was brought to operational capacity, fitted with a cloaking device and sent to investigate the Dominion Threat to the Federation.
After much testing, in the field the Defiant Class proved to be an invaluable asset to Starfleet, and as such the class was made active by Starfleet command. In the words of Captain Sisko though,
"The Defiant Class is a ship like no other. Every single starship I have served on learnt about its crew, and adjusted itself accordingly. The crews on these ships have it easy. The Defiant though. Well, lets just say you have to get used to the way she works. You have to be flexible and understanding to get the best out of such a powerful ship.."
The Defiant Class of starship was a hurried project that caused many divisions in the Advance Starship Design Bureau. The project at first officially labeled as the Valiant project, later changing to the Defiant project was briefed as a warship and twelve submitted designs were considered. Relative newcomer to the team, Dr. Joe Park was given the project after his usual design provoked much interest.
However after only six months in charge of the Defiant project, Dr. Park was killed instantly as the fore section of the navigational deflector fell on him.
Commander Sisko, on reassignment from the Orbital habitat development project was brought in as the new head of the design team. His experience in engineering and starship design fully qualified him for the job. Working closely with the design team and the Klingon designers, the Commander took the class forward, doubling his efforts to make the class a working machine. Over time the design changed slightly to incorporate the unusual weapons systems the Klingon's had designed for the ship and slowly but surely the prototype took shape.
After 18 months the USS Defiant was ready for launch.
The Defiant though was initially not to prove as successful as had been hoped. After the loss of the ships designer, Dr. Park, the design and production team found many difficulties with the ship. In the space of three weeks, the Defiant manage five times to only make it 1500 meters out of pod 13 before disaster stuck. The first time the IPS system fused completely, the second time the warpcore automatically ejected after a thermal overload and the fourth time the computer shut the suffered complete system failure.
By this time the test crew were beginning to feel the stress. Finally the ship left dock and managed barely to make it around the Terran system on its first true run. After another week of tweaking and redesigning the internal systems the Defiant left space dock on a one week assignment. After testing all primary systems the crew began the Review 4 testing. Warp One was achieved, although the test crew noted that it was a seriously rough ride. Maneuverability testing almost tore the ship apart. Upon a full power test of the warp core the ship suffered structural damage as the vibrational dampening system failed to counter the huge warpcore's torsional stress. The IPS system was throwing the ship around and the SIF and IDF fields were not capable of handling the touchy responses of the ship. And of course the Weapons systems were causing massive recoil when tested.
Starfleet has found the USS Defiant to be of a much better specification than originally deemed by the test crew. This is due to the many hours of work needed to 'tune' the Defiant. Many hours of research have gone into this 'retrofitting' process. Much of this redesigning work was carried out by Captain Sisko and Chief O'Brien of Deep Space Nine.
In the early 2390s the class was upgraded with improved phasers, slipstream drive, improved computer hardware with the latest LCARS version, and improved power allocation systems. In 2399, many of the first generation (initial production run) Defiant class vessels were decommissioned, including the USS Defiant herself. However, following the disaster of Frontier Day 2401, the class was put back into production but in limited numbers. The new production run incorporated new radiolytic emitters which improved overall phaser output and heat dispersion for longer sustained use for both pulse phasers and phaser arrays.
2365: Starfleet issues a brief for a long range, maneuverable warship as fears of a Borg invasion rise. Design plans commence at the ASDB.
2366: Twelve Design plans are submitted to the ASDB, the Defiant project is approved. Primary design work begins on the Defiant Class and the primary hull construction begins. By late in the year design work is still continuing with weapons consultants being brought in from the Klingon Empire. ASDB reconsiders the Type II MARA core as primary power source.
2367: Wolf 359 incident occurs crippling Starfleet. Fears of a second invasion mount as the Defiant Class continues under higher priority.
March: Basic chassis is manufactured and central computer core is Gamma Welded into place. Designs for a three chamber warpcore are send to the Propulsion dynamics lab for theoretical testing. Starfleet's Tokyo R&D weapons labs confirm an upgraded phaser cannon, using artificially grown emitter crystals, is possible.
June: Ablative Amour arrives from the Arteries Ship Yard. Outer hull is nearing completion except for the engine bay. Designs for the warpcore are approved and production begins at the labs on Jupiter.
November: Warpcore arrives and is Gamma welded into place. Outer hull fully sealed and internal fitting begins. Warp coils arrive and are welded into place. Front end redesigned to accommodate the modified weapons systems. A modified Sub computer core from the Galaxy Class project found to suitable for use as a main computer. Unit is installed and technical modifications begin
2368:
January: Warp field and weapons array problems
found in frontal half of ship. Work is stopped until a new design is decided upon. New
outer hull laid down over new front half of ship. Bridge module is attached. Crew quarter
are fitted. Computer becomes self aware.
April: New ablative Amour arrives and is installed over the new front hull. Preliminary testing of all systems complete.
June: Ship completes its first warp jump. Serious problems are discovered with the warp engines and the SIF (Structural integrity field). Problems are rectified as best possible. Testing of basic systems continues.
August: After full power weapons testing the ship is deemed unsuitable by Starfleet inspectors and the ship is ordered to return to Utopia Planitia to be placed in storage.
September: The Defiant Project is officially closed by Starfleet.
2370: The Defiant Project reopened after Dominion Threat discovered. With recent advances in technology work begins to cure the Defiant's many problems. Within a month redesigning and retrofitting work has cured the major problems and the first ship of the class, the USS Defiant is commissioned at Utopia Planitia, the ship shortly after being immediately assigned to station Deep Space Nine.
2373: Starfleet reviews the modification field work carried out on the Defiant Class of Starship and deem that although the class has major flaws, it is a very capable ship and with the new technical design information gathered by the Engineering team on the ship decides to place the class in Active production as fears of a Dominion war rise.
Technical Specifications for Defiant Class ships