You're a transport inbound from the local asteroid belt, hauling your load of processed metals, when an enemy raider show up on your screens. What do you do? You launch fighters.
Fighters are not of much use offensively in High Guard, at least not at the higher tech levels. The effort to give them enough computer to have a chance at hitting warships usually results in a large and very expensive fighter whose job could be more economically done by a size-A escort - 'cause high-end computers are just expensive as heck.
However, "BREAKTHROUGH STEP: A breakthrough occurs if all of one player's line of battle ships have been rendered incapable of firing any offensive weapons." A defender does not have to be able to hit to keep the enemy away from your reserve; it just needs to have offensive weapons.
(Odd little simplification. Presumably, if you tried to ignore a weak defender and charge past, those weapons would be more effective than they were when you were jigging around at 25,000 Km with full ECM going. On the other hand, if I'm a raider, it might be worth a few hits to get into the reserve. Still, it is what it is unless someone crafts an errata to allow you to push past under fire.)
When you're all alone and need to buy time for someone to come to your rescue, fighters - especially small fighters - can be very useful on the defense. In this role, smaller is better: it can't do much, a little fighter has the same size class and weapons as a big fighter, and you can carry more little ones.
Let's craft a Imperial light convoy fighter:
Armadillo: 10t Short-range Light Fighter, TL15
USP QFL-0606G01-F00000-20002-0 MCr 13.905 10 Tons
Bat Bear 1 1 Crew: 3
Bat 1 1 TL: 15
Cargo: 0; Fuel: 1.6dT; EP: 1.6; Agility: 6; Pulse Lasers
Architects Fee: MCr 0.139 Cost in Quantity: MCr 11.124
Cute little thing. No bridge, Model-1 computer, might chew up merchants, potentially quite deadly against warships if using nuclear missiles - if it could hit anything. For the most part, any warship with a halfway decent computer looks like so much snow on this little puppy's scopes. It couldn't hit a dreadnought unless you came up with house rules letting it get a lot closer, and I'm not sure a pilot wants to be that close when his nuke goes off.
However, if the job is to keep the raider out there, then under High Guard rules it's quite capable of holding someone off for a while.
Let's analyze:
First, this particular fighter is more a punching bag than a fighter, at least against warships. Good agility, but no electronic defenses to speak of. About 2/3 of small batteries will hit home, and big batteries will pretty much hit it at will. However, it's a very well armored punching bag.
Fighters as a rule are vulnerable to critical hits - lots and lots of critical hits. However, armor reduces those. Factor-15 armor eliminates criticals from weapons of up to Factor-7; beyond that, the fighter may take as many as 2 criticals, with the following probabilities:
x/36 roll effect
1......2 Ship Vaporized - destroyed.
2......3 Bridge Destroyed - no effect.
3......4 Computer Destroyed - USP computer factor reduced to zero, may
not jump but may continue to fire weapons and maneuver.
4......5 Maneuver Drive Disabled - crippled.
5......6 One Screen Disabled - no effect.
6......7 Jump Drive Disabled - no effect.
5......8 Hangars/Boat Deck Destroyed - no effect.
4......9 Power Plant Disabled - crippled.
3......10 Crew-1 - crippled.
2......11 Spinal Mount/Fire Control Out - no effect/crippled.
1......12 Frozen Watch/Ship'sTroops Dead - no effect.
Odds overall: 23/36 minimal effect (20/36 no effect, 3/36 computer disabled), 13/36 crippled/lost (3/36 loss of crew, 1/36 loss of crew and ship)
So, roughly 2/3 of criticals have little or no effect on a fighter (and most of the rest, the pilot can be rescued).
Routine damage runs like this:
NonNuke..Pulse L..Nuke..Nuke/Rad..Roll..Surface Damage..Radiation
.0...........0..........0.........0.........2......Critical...............Critical
...and so forth...
.0...........0..........0.........0.........16....Fuel-1...............Weapon-2
.0...........0..........1.........0.........17....Weapon-1..........Weapon-1
.0...........0..........2.........0.........18....Weapon-1..........Weapon-1
.0...........0..........3.........0.........19....Fuel-1...............Weapon-1
.0...........0..........4.........0.........20....Weapon-1..........Weapon-1
.0...........1..........5.........0.........21....Weapon-1..........Weapon-1
36.........35.........21.......36.........22+...No Effect...........No Effect
0/36 chance of damage from non-nuke/non-pulse weapons.
1/36 chance of damage from pulse lasers. 4 hits neutralizes fighter.
~15/36 chance of damage from nuclear missiles, 3/36 (fuel) neutralize fighter in 1 hit.
Net result: you have a little fighter that, while it's not a threat, can stand off smaller batteries firing anything short of nukes for a half day (the limit of a craft's duration without a cabin and relief crew); a pair of fighters working rotation gives plenty of time for help to come and beat back the attacker. Against bigger batteries, the crits tend to get it before the routine damage does, but statistically that still takes 3 or 4 shots before the odds get good - and 3 or 4 shots from a Factor 8-9 battery generally means you're opposing a destroyer or better, which means you ought to have several fighters on hand to hold it back. Against fighters or other small batteries with nukes, it tends to last about 6 or 7 hits; figure each one will buy you a couple of hours. In either event, they're small and easy to find room for, especially in transports, and if you're a military transport with good (5g) drives, you can break away under the cover of one.
The lone fighter himself has good odds. Only a crit or a fuel hit will stop him from driving at 6-g toward help, which is most likely driving at 6g toward him, and he's got an 89% chance of surviving a crit. He'll either last long enough for rescue to arrive or find himself alive in a dead ship waiting to be either rescued or captured. Since trashing a 10-ton boat isn't much of an achievement, most attackers will break off and go find more productive prey rather than run him down.
Something roughly similar can be designed at TL14, but you lose the laser. Doable at TL13 but you're not as heavily armored, though F12 is still pretty effective.
Fighters are not of much use offensively in High Guard, at least not at the higher tech levels. The effort to give them enough computer to have a chance at hitting warships usually results in a large and very expensive fighter whose job could be more economically done by a size-A escort - 'cause high-end computers are just expensive as heck.
However, "BREAKTHROUGH STEP: A breakthrough occurs if all of one player's line of battle ships have been rendered incapable of firing any offensive weapons." A defender does not have to be able to hit to keep the enemy away from your reserve; it just needs to have offensive weapons.
(Odd little simplification. Presumably, if you tried to ignore a weak defender and charge past, those weapons would be more effective than they were when you were jigging around at 25,000 Km with full ECM going. On the other hand, if I'm a raider, it might be worth a few hits to get into the reserve. Still, it is what it is unless someone crafts an errata to allow you to push past under fire.)
When you're all alone and need to buy time for someone to come to your rescue, fighters - especially small fighters - can be very useful on the defense. In this role, smaller is better: it can't do much, a little fighter has the same size class and weapons as a big fighter, and you can carry more little ones.
Let's craft a Imperial light convoy fighter:
Armadillo: 10t Short-range Light Fighter, TL15
USP QFL-0606G01-F00000-20002-0 MCr 13.905 10 Tons
Bat Bear 1 1 Crew: 3
Bat 1 1 TL: 15
Cargo: 0; Fuel: 1.6dT; EP: 1.6; Agility: 6; Pulse Lasers
Architects Fee: MCr 0.139 Cost in Quantity: MCr 11.124
Cute little thing. No bridge, Model-1 computer, might chew up merchants, potentially quite deadly against warships if using nuclear missiles - if it could hit anything. For the most part, any warship with a halfway decent computer looks like so much snow on this little puppy's scopes. It couldn't hit a dreadnought unless you came up with house rules letting it get a lot closer, and I'm not sure a pilot wants to be that close when his nuke goes off.
However, if the job is to keep the raider out there, then under High Guard rules it's quite capable of holding someone off for a while.
Let's analyze:
First, this particular fighter is more a punching bag than a fighter, at least against warships. Good agility, but no electronic defenses to speak of. About 2/3 of small batteries will hit home, and big batteries will pretty much hit it at will. However, it's a very well armored punching bag.
Fighters as a rule are vulnerable to critical hits - lots and lots of critical hits. However, armor reduces those. Factor-15 armor eliminates criticals from weapons of up to Factor-7; beyond that, the fighter may take as many as 2 criticals, with the following probabilities:
x/36 roll effect
1......2 Ship Vaporized - destroyed.
2......3 Bridge Destroyed - no effect.
3......4 Computer Destroyed - USP computer factor reduced to zero, may
not jump but may continue to fire weapons and maneuver.
4......5 Maneuver Drive Disabled - crippled.
5......6 One Screen Disabled - no effect.
6......7 Jump Drive Disabled - no effect.
5......8 Hangars/Boat Deck Destroyed - no effect.
4......9 Power Plant Disabled - crippled.
3......10 Crew-1 - crippled.
2......11 Spinal Mount/Fire Control Out - no effect/crippled.
1......12 Frozen Watch/Ship'sTroops Dead - no effect.
Odds overall: 23/36 minimal effect (20/36 no effect, 3/36 computer disabled), 13/36 crippled/lost (3/36 loss of crew, 1/36 loss of crew and ship)
So, roughly 2/3 of criticals have little or no effect on a fighter (and most of the rest, the pilot can be rescued).
Routine damage runs like this:
NonNuke..Pulse L..Nuke..Nuke/Rad..Roll..Surface Damage..Radiation
.0...........0..........0.........0.........2......Critical...............Critical
...and so forth...
.0...........0..........0.........0.........16....Fuel-1...............Weapon-2
.0...........0..........1.........0.........17....Weapon-1..........Weapon-1
.0...........0..........2.........0.........18....Weapon-1..........Weapon-1
.0...........0..........3.........0.........19....Fuel-1...............Weapon-1
.0...........0..........4.........0.........20....Weapon-1..........Weapon-1
.0...........1..........5.........0.........21....Weapon-1..........Weapon-1
36.........35.........21.......36.........22+...No Effect...........No Effect
0/36 chance of damage from non-nuke/non-pulse weapons.
1/36 chance of damage from pulse lasers. 4 hits neutralizes fighter.
~15/36 chance of damage from nuclear missiles, 3/36 (fuel) neutralize fighter in 1 hit.
Net result: you have a little fighter that, while it's not a threat, can stand off smaller batteries firing anything short of nukes for a half day (the limit of a craft's duration without a cabin and relief crew); a pair of fighters working rotation gives plenty of time for help to come and beat back the attacker. Against bigger batteries, the crits tend to get it before the routine damage does, but statistically that still takes 3 or 4 shots before the odds get good - and 3 or 4 shots from a Factor 8-9 battery generally means you're opposing a destroyer or better, which means you ought to have several fighters on hand to hold it back. Against fighters or other small batteries with nukes, it tends to last about 6 or 7 hits; figure each one will buy you a couple of hours. In either event, they're small and easy to find room for, especially in transports, and if you're a military transport with good (5g) drives, you can break away under the cover of one.
The lone fighter himself has good odds. Only a crit or a fuel hit will stop him from driving at 6-g toward help, which is most likely driving at 6g toward him, and he's got an 89% chance of surviving a crit. He'll either last long enough for rescue to arrive or find himself alive in a dead ship waiting to be either rescued or captured. Since trashing a 10-ton boat isn't much of an achievement, most attackers will break off and go find more productive prey rather than run him down.
Something roughly similar can be designed at TL14, but you lose the laser. Doable at TL13 but you're not as heavily armored, though F12 is still pretty effective.