The Ares class assault shuttle.
This class of shuttle was as much a vehicle for exploration as it was a weapon of war. To this end the best weapons that could be made by human technology were squeezed into the small frame of this shuttle. The primary weapon was a four shot rail gun that was powered by a cold fusion reactor. After every shot the rails were destroyed hence the small amount of shots. This gun had a range of 3000 km and could travel this distance in just under a minute. For the Invader's shuttle craft this was more then enough power to destroy them in one shot. Unfortunately unlike the highly romanticized versions of space combat popularized by Sci-Fi movies real space combat counted on being able to pinpoint the enemy and fire first before they fired. This meant that the two crafts could maneuver for days to get a bead on each other and without super sophisticated sensors such as ones found on the Hubble or Earth based sensor arrays. The biggest optical sensors were crammed into the frame of this shuttle but even they could not resolve anything farther then several hundred kilometers. It was up to mission control to relay information to the Ares shuttle so that they could better identify their enemies location and hopefully fire a round accurate enough to kill them. Communications even with the most advance collapsible antenna could still take minutes or even hours to relay the important information. However it is well known fact that the Invader's sensor technology is no that advance nor do they have orbital sensor satellites or any other infrastructure which the IAASA has in place. When it comes down to the actual fighting both sides crafts are fairly evenly matched but battle information is always heavily in the IAASA favour.