The following is a list of unnamed Klingon and Romulan starships of the D7-class.

By commanderEdit

By yearEdit

Interceptor near OrganiaEdit

D7 firing magnetic pulse

D7 firing a magnetic pulse

In 2267, an unnamed Klingon warship was a warship sent to Organia by the Klingon Empire a prelude to invasion of that planet. On stardate 3198, the vessel intercepted and attacked the USS Enterprise upon entering the Organian's star system.

After being hit by an unprovoked bombardment of magnetic pulses, the Enterprise returned phaser blasts, completely destroying the Klingon vessel. (TOS: "Errand of Mercy")

This was the first Klingon space vessel ever mentioned on Star Trek. While unseen during the original broadcast of "Errand of Mercy," it was later established as a D7-class warship in the 2007 remastering of the episode.
The English script in the Klingon language edition of the comic "Against Their Nature" establishes this ship as the IKS Vortha, a ship of a class of Klingon scout vessels, similar in design to the D7-class but about one third the size.

Klingon invasion fleetEdit

USS Enterprise-D7 face off

Enterprise faces off against the Klingon fleet

Following the declaration of war between the Klingon Empire and Federation, the Klingon fleet was spotted in the quadrant near Organia by Unit XY-75847.

Soon after, eight Klingon space vehicles, led by Commander Kor, engaged the USS Enterprise, driving it away from the system before they assumed orbit around the planet to deploy their invasion forces.

The two fleets were later prepared to engage each other outside of Organia, but were stopped by the Organians, who made all instruments of violence on both of the star fleets radiate a temperature of 350 degrees, effectively ending the battle before it began. (TOS: "Errand of Mercy")

This fleet was unseen in the original broadcast, but was established as being comprised of D7-class warships in the 2007 remastering of the episode.

Confrontation near Capella IVEdit

Klingon warship, Fridays Child remastered

A Klingon scout ship at extreme visual range

This unnamed vessel was a small class of Klingon scout ship/warship utilized by the Klingon Empire during the 23rd century.

In 2267 a ship of this class transported Kras to Capella IV, so that the Klingon agent could acquire the rare mineral found there called topaline.

The ship later lured the USS Enterprise away from the Capellan homeworld in an attempt to bolster Kras' position during negotiations, by first relaying false distress calls from the SS Dierdre and USS Carolina. When the Enterprise returned to Capella IV, the warship attempted a brief stand-off, but ultimately yielded. (TOS: "Friday's Child")

Klingon warship, Fridays Child

Original appearance

In the original broadcast of this episode, the exact classification of this vessel was given as somewhat obscure. Kras identified his ship as "a small scout ship," nevertheless, the ship encountered by the Enterprise, which may or may not have been the same vessel, was recognized by Pavel Chekov as a "Klingon warship," and was referred to in the false distress calls sent by the Klingons as a "Klingon vessel."
These inconsistencies were seemingly remedied in the 2007 remastered release of this episode, which visually established this ship as a D7-class warship. According to Mike Okuda, "The story situation required the ship to be very small on the screen, and we wanted it to be recognizable as a familiar Klingon ship. Small changes to the design would not have been noticeable, and larger changes could run the risk making the ship unrecognizable, especially since we only saw it for a few moments."
In recalling the original appearance, the script refers to the visual as "
a throbbing point of light pinpoints the Klingon vessel. (Similar effect as used in "Mudd's Women".)" and "the pulsing light that marks the Klingon vessel." Visually, this effect appeared as a flat shape with some sort of "handle" affixed to it.

Encounter at NeuralEdit

Klingon vessel orbiting Neural

Klingon vessel in orbit of Neural

This unnamed vessel carried Krell to the planet Neural in 2267.

The vessel was detected by the Enterprise arriving at Neural just as the Enterprise landing party was beaming up to the Enterprise. Because the Enterprise was on the far side of the planet, the Klingon vessel did not spot the Federation ship, which was confirmed when the Klingon's routine message to their home base, which made no mention of Enterprise. To prevent detection by the ship, the Enterprise maintained radio silence, and after beaming a second landing party down, it left orbit to hide from the Klingon vessel until the Enterprise landing party could complete its mission. (TOS: "A Private Little War")

This vessel was merely mentioned in the original version of the episode and remained unseen until its appearance in 2008 as the recurring D7 CGI model, for what was its final Star Trek remastered television appearance.

Pursuit in the Tellun systemEdit

D7 battlecruiser, EoT remastered

Pursuing battle cruiser

In 2268 this Klingon battle cruiser, working in conjunction with Kryton, attempted to destroy the USS Enterprise while it traveled through the Tellun system.

After Kryton sabotaged the warp drive of the Enterprise, it was the job of the battle cruiser to strafe the Federation starship in order to persuade it into engaging its warp drive and destroy the ship.

The ship was ultimately outmaneuvered by the Enterprise and limped back to Klingon territory. (TOS: "Elaan of Troyius")

Capture of the EnterpriseEdit

Romulans surround the Enterprise, TEI remastered

Romulan D7s

Later in 2268, two unnamed Romulan battle cruisers, and a unnamed Bird-of-Prey participated in the capture of the USS Enterprise after it crossed Romulan Neutral Zone.

They would eventually be outmaneuvered by the Enterprise after it engaged a cloaking device stolen from the Romulan flagship. (TOS: "The Enterprise Incident")

In the remastered airing of this episode, the Romulan D7s were donned with bird markings on their ventral hulls, much like that found on the Romulan Bird-of-Prey, which were not present in the original broadcast.
The novel The Romulan Way gives Talon as the name of the Romulan flagship in this episode. A sequel by the same author, Honor Blade, gives it as Memenda. These are presumably meant to be the same name, rendered in English and the Romulan language.

Encounter en route to Rator IIIEdit

D7 class approach Enterprise, The Survivor

Two battle cruisers approach the Enterprise

In 2269, two unnamed Romulan battle cruisers intercepted the USS Enterprise as it violated the Neutral Zone, while en route to Rator III.

During a brief engagement, the Enterprise disabled the propulsion units of the lead cruiser, and the power supply of the second cruiser, leaving the crew unharmed. Following the engagement the Romulan cruisers to moved off, the latter, according to Spock needed several days to complete repairs. (TAS: "The Survivor")

Mousetrap in the Delta TriangleEdit

Kuri's battle cruiser and sister ship

Kuri's battle cruiser and a second unnamed cruiser

Later in 2269, the ships, including the IKS Klothos, were involved in a mouse trap maneuver against the USS Enterprise in the Delta Triangle.

The commander of the lead sister ship was Commander Kuri, who contacted the Enterprise after witnessing what he believed to be the destruction of the Klothos, demanding their surrender.

After refusing to surrender, the two sister ships fired on the Enterprise, only to lose it from their sensors after it entered the region of space known as Elysia. (TAS: "The Time Trap")

Ambush of the EnterpriseEdit

Romulan D7s ambush Enterprise, 2270

Three D7s prepare for an ambush

In 2270, three Romulan warships ambushed the Enterprise from behind a type 4 asteroid, just outside the Romulan Neutral Zone.

They later pursued the Federation vessel deep into Federation space before retreating after failing to capture the ship. (TAS: "The Practical Joker")