Sphyrna-class corvette

"Those are our reinforcements? Some old transports?''" "''In our position, you take what you can get, kid."

- Ezra Bridger and Kanan Jarrus

Sphyrna-class corvettes, also known simply as Hammerhead corvettes, were a model of corvette that saw wide use in the period leading up to, during the Galactic Civil War and during the cold war, where they would be fielded by a rebel cell as well as the Alliance to Restore the Republic and the Resistance.

Characteristics
Sphyrna-class corvettes were inspired by a starship design that dated back centuries prior to the Imperial Era that was designed by Corellian Engineering Corporation. Throughout its existence, at least two different variants of the Sphyrna-class existed. The one most commonly seen utilized by early rebel cells featured a large ventral cargo bay and three dual laser cannon, as well as a vertically-elongated bridge section characteristic of the Hammerhead-class. In its early years, the Alliance to Restore the Republic continued to use this original model.

By 0 BBY, however, the Alliance had modified its previous Hammerheads, such as the Lightmaker, into a slightly different refit. Several new features were added to the original Hammerhead structure, including two extra modules mounted to the port and starboard of the craft, six escape pods in place of the cargo bay, and a fourth sublight drive mounted on top of the primary three, giving it enough power to single-handedly move a disabled Star Destroyer. This refitted model was the version used the most during the Battle of Scarif.

Early rebellion
After learning of rebel losses at the battle on Garel, Imperial senator Bail Organa of Alderaan dispatched his adopted daughter, Princess Leia Organa, along with three Hammerhead corvettes&mdash;Lightmaker, Amity's Arrow and Duchess Senna&mdash;to Lothal to expand the rebel fleet, under the guise of delivering relief supplies to the people of Lothal. The princess planned for the rebels to steal them to conceal Alderaan's involvement with the rebellion, but Lieutenant Yogar Lyste installed gravity locks to prevent the corvettes from taking off. With the help of former Lothal governor Ryder Azadi, who had constructed the locks while he was in prison, the rebels were able to commandeer the corvettes and add them to their growing fleet.

In 2 BBY, the former Sith Lord Maul assaulted one of the rebellion's corvettes. He interrogated the crew, leading to Maul capturing the Ghost personnel in order to unlock holocrons.

Later, Phoenix Cell escorted one of their transports to evacuate rebel sympathizers at Mykapo in front of an imminent Imperial takeover. The same transport, the red-painted P2, was later destroyed during the Battle of Atollon.

Galactic Civil War
"Call up a Hammerhead corvette. I have an idea."

- Admiral Raddus during the Battle of Scarif

After the rebellion was reorganized into the Alliance to Restore the Republic, several modified Hammerheads partially made up the motley assortment of vessels that was the nascent Alliance Fleet. One such ship was the Lightmaker, which was a part in Admiral Raddus' fleet just prior to the Battle of Yavin, under the command of Kado Oquoné. The vessel was present at the Battle of Scarif. During the battle, Raddus ordered it to ram into the side of the disabled Imperial I-class Star Destroyer Persecutor, causing it to crash into a second Star Destroyer, the Intimidator, and then into the Shield Gate, allowing the Death Star plans to be transmitted from the Imperial base on the planet's surface. After the transmission is received by the fleet, at least one Hammerhead corvette, (the Consonance) along with some of the fleet began the jump into hyperspace just seconds before the arrival of the Devastator.

At least one Hammerhead was still in the Alliance Fleet shortly after the siege on Tureen VII.

Cold war
One Hammerhead was part of the Resistance navy. The Sterdic Star was used during the mission to Taul.

Behind the scenes
Sphynra-class corvettes first appeared in "A Princess on Lothal," the tenth episode of the second season of Star Wars Rebels, which also saw the introduction of Princess Leia Organa on the show. The ships are based on the Hammerhead-class cruisers from the now Legends video game Star Wars: Knights of the Old Republic. In Linnaean taxonomy, Sphyrna is the genus name for the Earthly hammerhead sharks.

In Star Wars: The Rebel Files, an image of the Thranta-class corvette from the Star Wars Legends video game, Star Wars: The Old Republic, was used in place of a canon Sphyrna-class corvette.

Despite the specifications listing the ship as 315 meters, various episodes of Star Wars Rebels depict the vessel considerably smaller, especially in screenshots alongside the Ghost and other vehicles.

In the canon Fantasy Flight Games sourcebook, Dawn of Rebellion, the book establishes that the Sphyrna-class corvette is known as the Hammerhead-class corvette. It also establishes that it was manufactured by Rendili StarDrive, was worth 1,000,000 credits, was equipped with three RSD 88D-II BrightStar ion engines, had a class three primary hyperdrive and class fifteen backup hyperdrive, had a crew of 35 officers and crew members, with a passenger capacity of 125. It also had six months worth of consumables. Dawn of Rebellion and Star Wars Encyclopedia of Starfighters and Other Vehicles establishes that the Hammerhead-class and Sphyrna-class corvettes are intended to be the same starship, however, since the Star Wars Encyclopedia of Starfighters and Other Vehicles is the most recent source and is not a roleplaying sourcebook but rather an encyclopedia, this article assumes that the encyclopedia contains factual information.

Non-canon appearances

 * LEGO Star Wars: The Force Awakens