Ideas for how aliens would approach this fight?

Question

I had a handful of great ways for the opening battle of a space opera to go down, but they got totally scrapped when I changed how quickly jumping between star systems worked, and now intra-system travel works. What sort of tactics would the hive mind aliens employ?

The System

The planetary system is mostly small planets orbiting a dim yellow star. The second planet is inhabited by a fledgling colony, with a partial space station and some communication satellites. This planet is roughly the size of earth, but the remaining planets are much smaller (with the smallest being the size of mercury, and some of the larger almost approaching earth sized). There are three "jump points" located at the edge of the system (around 4 light hours from the star). These jump points are approximately equidistant from each other (or close enough that it can be hand waved). One of these is where the aliens have jumped in from, and another is where a reinforcing human fleet will be jumping in from eventually.

Common Technology

Both races have the ability to utilize jump points. Jump points are weak points in space that can be used to generate a kind of worm hole that leads to another star system. Speed through these jumps is variable, meaning smaller ships, that normally would travel faster through them, can slow down to arrive with larger ships that are slower. Time between stars is variable, but tends to be in the 20m-3hour range, depending on speed of the ship.

Both races have some form of intra-system faster than light travel. The humans refer to it as a Slipstream, a bubble projected around the ship that alters the physical characteristics of space, allowing for rapid acceleration/deceleration and faster top speeds. I've not set hard numbers, but one section has the frigate in system capable of travelling an average of 5x lightspeed, including acceleration/deceleration. This mode of travel is dangerous if disrupted, so it is not used in combat (basically disrupting the Slipstream results in a critical existence failure as real space physics take notice).

Human Technology

Humans have FTL communication and FTL sensors of an extremely low quality. They can, for example, detect weapons discharges and detect where a ship is in space, but cannot get visuals or any fine detail until light comes in at the normal speed. One ship can relay visuals to other ships in realtime, though.

Humans can communicate through jump points via relay buoys positioned at the jump points. Failure of these buoys destroys this ability, and buoys must be present at both ends.

Humans have energy shields to protect most of their ships. These shields are effective against most weapons and debris.

Humans use artillery or railguns to launch shells into space. The shells then fire off a small booster that further accelerates them to combat speeds and provides some maneuverability. These shells have a variety of payloads (with "space napalm" and shrapnel being popular choices)

Humans are physically identical to earth humans.

The Aliens

The aliens are insectoid and have a mild hive mind that extends over a range of around 2km. Think of this like a distributed computing network. The more there are the smarter they are collectively, and the faster their thought process and reaction time. This is caused by a mild latent psychic field, and does not impact other races. Each individual is capable of independent action, though many follow the collective will of the hive.

The aliens utilize energy weapons of an unspecified type (fell free to go wild with this). They have a relatively short effective range, but are very powerful.

The aliens do not utilize shield technology, but their hulls are heavily armored. This makes them slower.

The fight

A Human frigate (30m height x 210m length x 60m width) was orbitting the habitted planet when an alien destroyer (40m x 260m x 80m) jumped in, destroying an engineering vessel at the jump point. The frigate enterred a Slipstream to engage, when two alien light cruisers jumped in (50m x 320m x 90m). Dropping back into realspace, the frigate reversed course and slipstreamed back to the planet, calling for reinforcements.

Human reinforcements will arrive at their jump point in around 45 minutes.

Aliens have made no move further into the system, and are at their jump point. For these vessels, it would take around 15m to get into combat range of the planet or the frigate.

The human frigate's mission is to defend the colony at all cost (but they'd obviously like to survive).

The alien's mission is to gather information about the human fighting capability, and wipe out everything in this system, including the comm buoy.

The aliens are aware of the possibility of human reinforcements. There are no alien reinforcements available.

UPDATES:

Human reinforcements are a full defense fleet, so a battleship, multiple heavy cruisers and lots of escorts. If this fleet arrives, the aliens will need to flee or be wiped out

In system, humans have this frigate, and a handful of cheap fightercraft that won't do much.

The aliens have encountered a few human vessels, and are aware of the fact they have shields. They are not aware of the human reinforcements, or which jump point any reinforcements will come from.

In case it wasn't clear above, the aliens do not have FTL sensors in any way. They are entirely reliant on the speed of light for their sensor data. They also do not have FTL communication

Alien motivations are decimation. They see this system (and perhaps others) as theirs and they will cleanse it of human presence, with a later goal being colonization.

In terms of relative strength, assume that, per normal naval nomenclature, a frigate is a small, fast, lightly armed ship, and each heavier step of ships gets better armed and slower.

What tactics would the aliens use?

Answer 1

Limited by light-speed sensors and with the humans having in-system FTL, the aliens are basically blind. The frigate only needs to charge straight at them, such that its weapons hit the alien ships before the light reflecting off it does. For one millisecond, the ship will be visible to the alien as it races between their ships, then it will be gone past them at a pace that their weapons can never catch up with.

It is sort of like when a drunk is attacked by a bee.

Fortunately, the frigate can't really hurt the heavily shielded alien ships so unless the frigate captain is smart and lucky enough to take out the sensors during the first attack, they will be able to study the frigate's design by watching the light which streams to them in the passing frigate's wake.

As the aliens are here to learn about human offensive and defensive technology, they should pretty much ignore the bee and focus on the planet.

Leave the smallest ship at the jump point to carry information home (in case the other two are destroyed). Then send the bigger ships towards the planet to blast it with everything they've got.

As the two larger, sacrificial ships test the human defenses, have them constantly reporting back all details to the destroyer over speed-of-light communications. Meanwhile, the destroyer must stay ready to escape by jump point if they are attacked by anything other than the frigate, or if reports from the destroyers' turn negative.

If any of the speed-of-light messages report the arrival of additional ships or the destruction of either of the larger ships, the destroyer must escape immediately with whatever details that final message contains.

Answer 2

The hive mind would not be very effective in a space battle with such a limited range of 2km. Ship board operations would be smooth as butta, but ship to ship cooperation wouldn't be any better than a human fleet.

With this in mind, the aliens have a few goals

1. Primary - Keep one ship intact to report back to the hive
2. Secondary - Recon the planetary and ship arrayed offensive/defensive capabilities
3. Tertiary - All three ships survive and return to the hive

Destroyer engages the human Frigate at distance, targeting shield generators and gun emplacements - they'd like prisoners if possible.

Cruiser 1 begins scans of the Frigate for offensive/defensive capabilities as well as energy and life form signatures, providing support to Destroyer as necessary.

Crusiser 2 destorys the comm buoy, sends drones to hack the planetary comm satellites and begins planetary scans for human populations, radio and energy signatures.

Cruiser 1 joins Cruiser 2 for a knowledge dump. Cruiser 2 jumps.

Cruiser 1 takes up flanking position behind the Frigate, targetting engines.

Destroyer, having taken mild hull damage from "napalm", has succeeded in bringing down the shield generator by lazing the shield with a reverse frequency beam, causing an overload. The human artillery never makes it to the Destroyer, being too slow and easily vaporized by alien energy weapons. Gun emplacements are easily rendered useless.

The planet has fired several tactical nukes in a desperate attempt to take the aliens out, but like the Frigate's artillery, these are met with immediate destruction

Cruiser 1 has quickly disabled the engines without destroying the ship and has engaged a tractor beam, towing the disabled ship toward the jump.

Destroyer leads the way to engage any human hostiles that might come through the jump first. None are seen.

Cruiser 1 jumps with Frigate in tow.

Destroyer deploys tracking mines and then jumps as well.

The first human Battleships emerge from the jump, too late, and are hit with the tracking mines, disabling, but not destroying the ships.

The war has begun.

Answer 3

Given that the aliens are unaware of the Human re-enforcements, this seems like a potential full loss scenario for the aliens.

If the alien will is strong and they know what they want, these cruisers will immediately move to decimate the colony. If the aliens are concentrating on what they can learn and what tech they could pillage, you get a different story. So two secnarios.

a) The aliens don't really give a crap about the humans pathetic technology and just open up from orbit to destroy the colony. If this is the route the aliens choose, there is little chance of survival for the colony.

b) the aliens want to learn more about their human enemies and are going to attempt a semi ground assault with cruiser support to try to recover and analyze as much human technology as possible. In this case, we've now got a longer ground battle that the human reinforcements are going to walk in on.

Whichever way you want your story to go.

Option A makes for a pretty blunt and quick intro scene...aliens arrive, destroy comm buoy, destroyer hunts and engages the frigate, frigate destroyed...cruisers come in and blast the colony from orbit. And all in enough time to get out prior to reenforcements. Kinda boring hey?

Option B is a bit more fun. Aliens arrive and the destroyer finds the comm buoy. The destroyer hunts the human frigate, however the human frigate evades using moons and/or planets to hide itself. Alien light cruiser #1 takes a moment to scan the colony and discover there is enough technology (yay shields!) that they want and prepare for a ground assault. Cruiser #1 takes the time to recover the comm buoy (FTL communications for us too? you bet!). Cruiser #2 moves towards the planet and prepares itself for a ground assault. It scans and identifies the planets defences and opens up from orbit to destroy a few key defensive facilities before sending out it's landing craft.

Now you get a ground engagement of aliens vs a frantic human colony fighting for survival. It's a close fight and it may look like the humans are getting the upper hand on the ground. The humans on the ground start to see that they might win this and begin celebrating..but its just a bit too early as Cruiser #1 is done recovering the buoy and arrives on the scene. The second set of alien landing craft appear on the horizon. Just as the human colonists are dealing with their impending doom (right after nearly celebrating victory...great high followed by great low), the human frigate appears from behind a moon and fully destroys the second set of alien landing craft much to the delight of the colonists...but it's a suicide mission as the cruisers easily lock on to the frigate and destroy it. As the alien commander looks at the exploding human frigate, his attention is quickly turned to the incoming volley from the human reinforcements that closed during the land battle. Scene ends in a massively bright explosion as the alien crafts are destroyed.

Scene reopens with a picture of the newest human fleet, each vessel named after one of the crew members of the heoric frigate that gave itself to defend the colony.

Answer 4

In your scenarios, the jump points function as perfect bottleneck, providing the colonists with a comparatively small area to defend. The mine fields which surround those jump point should be able to take out the three alien vessels without any friendly losses. Sort of like the StarGate's IRIS but with fireworks!

Answer 5

For this idea, I'm assuming these things: Aliens have explosives, and slow-moving objects can penetrate the shields. Seeing as the aliens are hive mind, this means that the mind doesn't care if a few drones die. I think a sending a small kamikaze sabotage pod to transport the alien into the frigate via a drill would work, then the alien would blow up, rupturing the hull. I just love the act of sabotage.