Structural Integrity Fields

So what are these structural integrity fields and why should I care? Structural Integrity Fields are a product of force field technology. They allow spacecraft to be constructed at a reduced cost and weight, while also permitting warcraft to be more survivable. A SIF is a system of planar force fields which are formed inside bulkheads and structural members to strengthen them. An SIF increases the amount of stress that such a bulkhead or structural member can take before it fails. As a side benefit SIF will prevent gravscanners and other force based technology from penetrating a hull which is reinforced with a Structural Integrity Field.
So how do I handle this in the game? An SIF allows a ship to be built as if it was built with a heavier frame, without the weight penalty. So in the GURPS VE2 or modular spacecraft system normally Hit points for a hull are calculated using the following formula:

area * 1.5 * Frame Value

Frame	Frame Value	SIF
Super Light	0.1	0.5
Extra Light	0.25	1
Light	0.5	2
Medium	1	4
Heavy	2	8
Extra Heavy	4	16

When a vessels has a Structural Integrity Field its Hit Points are calculated using the SIF multiple. It's cost is calculated as for the next highest Frame Value.
So for a vessel with a Super Light Frame the cost multiplier is normally 0.1. Outfitting the vessel with a Structural Integrity Field will raise the Hit Point multiplier to .5 while leaving the Mass Multiplier at .1, but the cost will increase to .25, still less then the 1 multiplier used for an equivalent light frame vessel. The technology's benefits are most dramatic at the heavy and extra heavy frame level used by Men 'O War.
Structural Integrity Fields do add a layer of cost and complexity to a vessel but the benefits are great enough that even small craft, such as brakes and HUVs often have them.

Anti-Missile Game Mechanics

As for other space combat mechanics in the game this section assumes GURPS VE2 rules modified using New Diapsoria modifications 
Assuming a Sensor Net Anti-Missile Missiles (AM Missiles) may be deployed whenever missiles are detected within a range of 1 million miles (100 hexes). From a game mechanics point of view an AM Missile which passes withing the same hex as an attack missile is an automatic kill, unless penetration aids are being used. In the case of an active Jammer there is a one in six chance of a missile hitting an actual missile as opposed to a false or spoofed missile. The GM records a number. If the attacker rolls that number it is a hit. If not a miss.
When jamming is used with a large number of missiles it becomes purely a numbers game. Determine the number of attacking missiles and subtract the number of anti-missile missiles to determine the number of missile which survive. At space combat ranges it is beyond the ability of sensors to determine the actual number of attacking missiles so for the defender it is a game of probabilities. If the defender launches too few AM Missiles attack missiles will get through to their targets. If the defender launches too many AM Missiles the excess missiles will be wasted and might be needed for subsequent attacks.
If penetration aids are used six times as many anti-missile missiles must be launched to stop every missile.
So if an attacker launches 300 missiles and the defender launches 200 AM Missiles, 100 missiles will survive to face the defender's point defense. If the attacker has used penetration aids then only 200/6 missiles (33.3, round up to 34) missiles will be destroyed and 266 missiles will survive to face the defender's point defense.
In the space combat round any missile within 10 hexes (100,000 miles) will be destroyed within the launching turn of the anti-missile missiles. Missiles within 40 hexes (400,000 miles) will be destroyed the turn after AM Missiles are launched. Missiles at 100 hexes (1,000,000) will be destroyed two turns after the AM Missiles are launched. Of course anti-missile missile ranges may be extended by launching them from a heavy missile booster package.  In that case the 500mm missile may travel to it full range before deploying it's 10 Viper anti-missile missiles. The Vipers accumulate the heavy missile acceleration as well as their own. Some ship launch Vipers from gravity pulse launchers which will give an extra 1000 Gs of initial acceleration. This really has little effect on game play because of the 10,000 mile hexes used. Difference in range and velocity are lost in the noise.

500mm attack missiles accelerate by one hex every turn. 250mm attack missiles accelerate by one hex every other turn. Missile with laser communicators may be commanded to move at any acceleration up to their maximum acceleration each turn. They may also be made to hold station, creating an kind of space mine which can then attack as the result of a remote trigger from a ship or station.
Any missile which survives will face the defender's point defense. Point defense consists of X-Ray Lasers and railguns firing canister shot. X-Ray Lasers are one-shot/one-kill weapons. In the anti-missile roll they are operated at reduced power and a higher rate of fire. Each laser will kill one missile per turn. For example a quad turret can kill 4 missile per turn. As for anti-missile missiles take the number of attacking missiles and subtract the number of point defense lasers to determine if any missiles survive.  Canister shot is an area effect weapon capable of destroying multiple missiles. This is because the range is so short because kinetic kill missiles and contact nukes must converge on the target in order to damage it. Any missiles which do not employ a "pop-up" trajectory will be damaged by canister fire.
X-Ray laser warheads detonate outside the range of point defense lasers and railguns. Such point defense weapons are ineffective against these weapons.

Sensor Drone Design

Using GURPS sensor rules if missile are allowed to utilize stealth technology and emission cloaking they become effectively undetectable at anything resembling useful ranges. This is especially true of missile which use some kind of gravity drive system, such as the B/G Engine, which itself is not highly detectable, except using a gravscanner. Gravity emission masking, which is available at TL A makes even that method of detection ineffective.
The answer in the New Diasporia universe is the use of sensor drones. To detect stealthed missiles a sensor net, consisting of hundreds of sensor drones are deployed. Such nets are deployed as far forward, that is as close as possible, to the perceived threat.
The goal is to deploy a sensor array that missile will have to physically pass. Optimum deployment forces missiles to approach  the sensor drones at a range of no more than 10 to 20 thousand miles at least half a million miles out from the fleet. This will give almost 11 minutes response time for anti-missile launch. As for many of the game mechanics of New Diasporia I have pillaged freely from other GURPS science fiction space based games. The Sensor array Rules are based on the home brewed rules for GT Sensor Arrays by Kenneth Witt located at John G Wood's elv GURPS Traveller site.
As with all my designs I run against the GURPS 3rd Edition TL progression limits. For most technology GURPS assumes that items which are developed in a specific TL cost half as much in the next TL and weigh half as much. Two Tech Levels after their introduction they weigh a quarter as much and their costs is again halved. They may also become more effective. Beyond that no improvement is seen. As one can see in the case of many devices this is not reflective of reality. Computers are an excellent example. Moore's law seems to have no boundary. Room sized at TL6, PC size at TL7, cell phone size at TL8, perhaps pin size at higher TL's. The cost was reduced at an even greater scale.
Rather than limiting progression to two tech levels I allow progression to continue. Since New Diasporia TLA is equivalent to GURPS TL14 in many areas, for sensors designs I continue to reduce sensor cost, mass, and volume for every Tech Level until TL14.
On this basis numbers for TLA sensor systems are:

PESA	TL	Scan Rating	Range	Hex	Mass	Volume	Cost
	A	51	4.5M	450	46.875	1.25	75

AESA	TL	Scan Rating	Range	Hex	Mass	Volume	Cost
	A	51	4.5M	450	4.45	0.5625	1.22

Gravscanner	TL	Scan Rating	Range	Hex	Mass	Volume	Cost
	A	42	.45M	45	0.703125	0.225	8.0

Using the modified sensor rules there is a +3 scan if >100 sensor platforms are used. If 300 sensor drones are deployed to cover a band of space between the attacking ship and the defender then the mass, volume and cost will be spread over 300 drones. Additional cost of the drone will be the B/G engine, Nuclear Power Generator, three laser communicators and a robotic computer brain. Individual drones will have radical stealth and emission cloaking.
Each drone will have a PESA  2.08 cuft sensor package, costing P2500, a AESA 1.0 cu ft sensor package costing P40.75, and a Gravcanner .375 cuft sensor package costing P5.6. Scann ratings for the whole system will be PESA:54, AESA:54 and Gravscanner:45.
A roll less than 4 on 3x6d will result in detection of a single 500mm missile. Obviously if 100 missiles detection odds are rolled the chance that some of them will be detected is almost a sure thing. So much so that a roll isn't necessary. Because the net is dispersed ignore the scan rating limit of size+36. Its actual size will be greater than size+36, but since each drone must be detected separately (for targeting purposes at any rate) this limit is unimportant.
Such a sensor net requires a signal processing program in a complexity 7 computer in the control node. The node is usually a forward deployed fighter or battlerider, although it can also be a destroyer or destroyer escort, which have the further benefit of being able to deploy the sensor net themselves.

Airlock Technology

An airlock is a device which allows movement from one kind of environment to another, while maintaining separation between the two. By the time of the New Diasporia airlocks have been in use for hundreds of years. Most spacecraft will have some form of airlock to allow people and objects in the shirtsleeve environment inside the craft to get outside the craft without completely depressurizing it.
The most elementary form of airlock consists of a room with two doors. Each door opens into a different environment. In the case of a spacecraft one will open into the hostile environment outside the ship and the other into the human standard environment inside the ship. Some primitive ships in the Wilds still use this technology.
More modern airlocks use much more sophisticated technology. Modern small craft, especially low tonnage commercial craft use an Airlock Containment Unit. An ACU is a device which is primarily mounted under the deck of a vehicle adjacent to the egress door. The ACU contains the air recovery system and a containment made of smart material. When the unit is in the stowed position it is out of the way and can be walked across like any other section of deck. When deployed the smart material expands to lock into the assembly mounted in the overhead and along the bulkhead. The overhead assembly usually contains a decontamination system. ACUs are available in a number of sizes, with the smallest just big enough for a single person. The ACU has no second door. Its user steps into the delineated square and activates the device which causes the walls to expand and isolate the area. The air is pumped out and the outer door to the vessel opened to allow egress. Most are controlled directly by the vessel's computer, although most also have an emergency power source and manual controls.
A more conventional airlock system for a larger craft consists of a multi-layered airlock system. The typical external airlock door consists of a blast door or safety shutter, which is normally closed during ship operation. Around the external door is typically a docking ring of compressed smart material which can be extruded to create a passage tube between vessels.
Behind the blast door is typically an airlock membrane. Membranes are v-branes which are selectively permeable. That means people and object can pass through them, but atmosphere can't.
A more advanced airlock consists of an opening with a brane which will allow vehicles or individuals to pass through while retaining atmosphere. An airlock planer force field acts as an emergency barrier should the brane fail.
A typical airlock on the most advanced vessels consists of a set of walls which form the airlock each with its portal protected by a brane, with an emergency planer force field and backup blast doors.
While the normal method of airlock control is through the ship's computer most airlocks have control stations located inside the airlock and at each portal. The inner control station typically has a touch panel which will  have controls for both sets of doors and for the planar force field. An interlock will prevent de-energizing both planar force fields at the same time. If a force field goes down the blast doors will close.
The station inside the airlock has controls for both the inner and outer portals. Emergency handles allow the brane to be manually deployed and emergency buttons can activate the force field and shut both sets of blast doors.
The outside control station typically has a communication terminal to allow a visitor to "knock" at the airlock door if the blast door is closed. It is possible to set the brane to keep out anyone not recognized as having authorized access, which is typically established using a wireless transponder or RFID tag.
An atmospheric testing station, which monitors the environment outside the outer door and in the airlock itself is also typically available, usually on the same touch panel as the controls. In normal operation the inside of a modern Tech A airlock is at ship's pressure, even during use. Should the brane fail if the planer force field deploys properly there should be little or no drop in pressure. If the force field should fail the airlock can be cycled in emergency mode from any of the three control stations.
A biofilter field in the brane can selectively keep out dangerous microbes and macropests. Still almost all serious airlock systems include a decontamination system and a dust recovery vacuum system to protect the vessel interior.
Airlocks can also be located between compartments of a ship, but it is much more common for a modern ship to have planer force field projectors installed to allow the ship to be segmented. Men 'O War typically supplement damage control force fields with pressure doors. Each pressure door consists of a pair of heavy sliding hatches with a small compartment between them. brane curtains, which will be activated by falling pressure, even without ships power, provides a final line of defense in preventing catastrophic depressurization. Segmenting barriers always include pressure displays to indicate the pressure on the door's far side.
Closed doors can be remotely overridden using the ship's computer, provided one has the proper access. They can be manually overridden only with the proper tools. If air is rushing past an open door it will automatically re-close unless disabled.

Of Saints and sinners.

In discussing character attributes it was mentioned that one of the goals of Characters in New Diasporia should be the quest to sainthood. It is not a goal every Player Character will attain to, but it is one to which some PC's should, if New Diasporia is to be different from every other space based science fiction RPG.
As was discussed every Character starts out with a level of holiness. The default starting level for any baptized character should be initially high, based upon their lifestyle. In what way do I mean? If the character is a Christian, and by design most characters will be Catholic Christians of one of the rites, East or West, then they must be what is commonly called a practical Catholic.
What is a practical Catholic? A practical Catholic is someone who follows the precepts of the particular rite of the Church to which they belong. So if they are a Roman Catholic they will abstain from meat on Fridays, attend Mass on Sundays and Holy Days of Obligation, and at least make their Easter duty of going to Reconciliation and receiving Communion. If they are members of one of the Eastern rites during Lent they will follow the strict fasting of Pure Monday and Great and Holy Friday. On Wednesday and Fridays in Lent they will keep the simple fast.
And they will adhere to the teachings of the Church on matters of faith and morals.
It is likely that in the course of their adventures that most Player Characters will fall. It is a component of the human condition and a Player will really want to have his character become a Saint to take the hard road. Becoming a martyr, when you've spent a good time building a character is not any more pleasant than the thought of real life martyrdom, though of course no where near as painful. So most characters will now and then take the easy way out.
Does that mean their quest is over? Not at all. As in real life a character can seek out a priest to receive confession.
So how is the game master ne referee ne storyteller to know where the lines are for characters? It's quite simple really. If the PC is following the authentic teaching of the Church then they are good. If they are going against it, even for good reason then they are not.
The difference between disciplines and dogma are discussing in broad terms here. Beyond that, look to the Catechism of the Catholic Church, in this matter it is your rulebook. (Don't be afraid to apply it outside the game too.)

Pentaids, sensor probes and ECM drones.

Pentaids (Penetration Aids) are basically 500mm missile modified by having their warhead replaced with jammers. They have the ability to spoof targeting systems so as to make a single missile appear to be multiple missiles or a single flight of missiles appear as multiple flights. The purpose of Pentaids is to cause anti-missile missiles to expend themselves uselessly against targets which do not exists.
Pentaids are fired from standard missile launchers and expend themselves quickly, that is they are meant to travel at standard missile accelerations (1000Gs) and have a duration no longer than the missiles they are based upon.
They are very effective against the terminal guidance systems of anti-missile missiles, but somewhat less effective against ship based sensor platforms.

Sensor Probes are modified 250 mm missiles. The warheads are removed and smaller engines are installed. Some retain their normal energy cells, others are outfitted with Nuclear Power Units (NPUs) which give them longer endurance. For some purposes their laser communicators can be replaced with standard encrypted EM communicators, An advanced compact robot computer is installed. The sensor packages used are very much weaker than those available to a spacecraft, but the purpose is to get the probe in close without detection. To this purpose they have the ability to operate independently, following very complex program guidelines to reduce the likelihood they would be compromised.
Most probes use sensor packages optimized for a specific purpose. All have some level of PESA capability, but beyond that they may be either primarily passive platforms or primarily active platforms.
Large numbers of probes can be deploy to create a passive sensor net. Active probes can be combined with passive probes and passive shipboard sensors systems to create pseudo-passive sensor nets. These nets operate very much the way the human eye does, or the way sonar buoys do. The active probes send out an EM wave pulse which reflects off of targets. The reflected waves are picked up by passive sensors disclosing information about the targets, just as the human eye sees objects illuminated by the sun or another light source. The enemy can attempt to take out the broadcasting active sources, but cannot detect the passive receivers.

Drones are also based on 500mm missiles, but not only have their warheads been removed, but they have smaller engines and NPU (Nuclear Power Units) rather than Energy Cells. This allows them greater endurance. Drones are used to spoof enemy sensors by jamming, distortion, or projection. A drone can make a Battlerider appear to be a Dreadnought, or making a destroyer seem to be a whole squadron of destroyers.