The Ha'tak-Class mothership was the primary capital ship used by the Goa'uld. A Ha'tak carries a sigificant arsenal of Heavy staff cannons for ship-to-ship warfare and orbital bombardment as well as serving as a carrier for dozens of Death Gliders while being able to service other spacecraft and carrying up to a thousand Jaffa warriors. Ha'tak class ships can enter planetary atmospheres. The number of Ha'tak class ships is believed to be in the hundreds. Cronus' Ha'tak had a speed of 32,000c.
The primary armament of a Goa'uld Ha'tak are it's heavy staff cannon turrets for ship-to-ship combat. These have been been given on screen a firepower of up to 200 megatons. Hat'tak also are equiped with a set of faster-firing, anti-fighter staff cannon turrets.
JACOB We're entering the coronasphere. The good news is that we won't show up on anyone else's sensors. The bad news is that our sensors will be blocked as well. CARTER So when we're ready to go, we won't know if someone's out there, waiting for us. DANIEL How long do we have? JACOB About an hour without full shields. Ten hours with. Sam, want to give me a hand?
A Ha'tak-class mothership is capable of sitting inside the Coronasphere of a blue giant for an hour without shields and ten hours with shields.
The hull is also strong enough to take the combined assault from three Ha'taks for several minutes.
The Ha'tak-class is powered by a large naquadah reactor. Ha'taks also have an emergency power core.
A Ha'tak has an unusual design with a pyramidal core surrounded by an external framework. A Ha'tak-class ship is six to seven hundred meters across. Ha'tak class ships have hangers capable accomodating Tel'tak and Al'kesh-class vessels, as well as specialized racks for storing Death Gliders.
Normally, a Goa'uld Ha'tak-class ship has a large crew of Jaffa and Goa'uld technicians and overseers, but it can be operated to some degree with only a helmsman (at least for short periods of time).
Over the course of the Stargate franchise, several distinct variants on the Ha'tak design have appeared. This does not include various superheavy flagships that the Goa'uld have built.
The first variant was Ra's Mothership, which lacked the external framework common to most Goa'uld Hat'aks. The general belief is that Ra's pyramid ship was not a military vessel, but a sort of personal yacht used by the most powerful of System Lords to go about his domain.
After Apophis usurped control of Sokar's empire, a second variant was seen, an advanced prototype for a new and improved class of Ha'tak. The performance of this variant is unknown, as SG1 destroyed it before its completion, and no other craft of it's class appeared before Apophis's final Death.
Later still, Anubis fielded a fleet of improved Ha'tak-class ships. These featured improved shields and weapons, allowing it to take on an Asgard Beliskner-class spacecraft, although they could still be defeated by normal Ha'taks. These ships, unlike Apophis's prototype, were not specially built with improved systems, but rather were merely upgrades of conventional Ha'tak-class ships. In case of its weapons systems, it is not known if this is an improvement in firepower or merely penetration.
One Ha'tak ship was captured by Stargate Command, the former flagship of the System Lord Cronus. It was then transferred over to the Tok'ra and was soon destroyed by SG-1 (along with Apophis) after it got infested with Replicators.