Levels of Protection

Just like characters and vehicles can be armored, buildings and structures can be reinforced to reduce damage from bombs.

“The extent and severity of damage and injuries in an explosive event cannot be predicted with perfect certainty,” noted a U.S. Federal Emergency Management Administration documentabo ut the effects of an explosive blast. “The air blast shock wave is the primary damage mechanism in an explosion. The pressures it exerts on building surfaces may be several orders of magnitude greater than the loads for which the building is designed.”

While the FEMA document is geared toward guarding against terrorist car and truck bombs, it can be used to infer what would happen when an aerially delivered bomb or artillery shell or missile lands near a building. The U.S. Department of Defense lists several levels of protection for buildings against the effects of explosions. We will adapt these levels for the Star Frontiers game.

Note, the following chart can be used for determining what will happen to a structure from most conventional attacks – bombs, lasers, missiles, artillery, demolitions, etc. But it does not necessarily offer a guide of what a weapon of mass destructions, such as the use of a nuclear warhead, will do to a building or to those inside.

Beyond the high level of protection, there are military structures that are virtually impenetrable, such as a bunker built into a mountain with blast doors that can absorb a nuclear explosion. Even with such a fortress, there are probably ways to get inside of it through emergency – and probably secret – exits where hatches can be blown up, allowing intruders to enter.

Explosions and Craters

Craters are formed in the ground when an explosion occurs either at the surface or immediately above or below the surface. Many craters are bowl-shaped, but there are several exceptions. This shape is caused by high-pressure gases and the resulting blast shockwave.

Writer Peter Hibbs of the United Kingdom has a blog at pillbox.org.uk, for a research paper called “The Defence of East Sussex Project.” He noted that during World War II, the British Home Office’s Research and Experiments Department offered some information on the effectiveness of German bombs and the types of craters they left. Please see the chart below.  

This information could be useful to a referee when determining what happens when a bomb or shell hits. Keep in mind, the chart about crater sizes is for a World War II era bomb, rather than more powerful explosives that would be used in a Frontier bomb.

Hibbs also references a 1942 UK manual called Bomb Reconnaissance and Protection Against Unexploded Bombs. That document notes that the size and shape of a crater and how far a bomb penetrates into the ground depends several factors, including:

·        The composition of the ground. Bombs, for example, would have a hard time denting granite.

·        Heavier bombs tend to be able to penetrate soils easier.

·        How high up a bomb was dropped – up to about 15,000 feet (approx.4,500 meters) after which there is no added penetration. For game terms, figure that this is for planets with approximately 1 G gravity that has any more than a thin atmosphere.

The bowl-shaped crater in figure 1 was made from a bomb that exploded on or shortly after impact. The actual size may be much larger, but material ejected upward (ejecta) may fall back in and erosion and landslides from the walls will partially fill the crater back in. 

Figure 3 shows a surface crater and camouflet from a bomb that deviated from its original trajectory but exploded.

Figure 4 shows a surface crater and camouflet from a bomb that exploded underground, but only a small surface area was affected.

Figure 5 is when a bomb explodes too deeply in the ground to form a crater on the surface, but soil may be heaped over the camouflet. This soil covering may collapse when a character or vehicle travels over the area.

Craters and camouflets are potentially dangerous. Along with the possibility of encountering an unexploded bomb, the pit may have poisonous carbon dioxide or other gases lingering inside!

Concluding Notes

For the sake of brevity, this concludes Part 7 of “Things that go boom!” The next article will return to looking at dropped ordnance, along with looking bombs with other types of warheads, including aerial deployed minefields, aerial resupply containers, and bomb disposal equipment.

Bomb Detonators. The bombs provided in “Tanks alot!” seem to just have contact detonators, but just like demolitions and mines, a variety of detonators are available. These detonators must be purchased separately and installed before the bomb can be successfully used! They will add weight to the device.

15 Kilogram Bombs. This is the class of weapons that were called the light bomb in “Tanks a lot!” Instead of just having a fragmentation explosive, a variety of warheads are available for bombs including electrical discharge, field crusher, foam, gas, incendiary, sonic and even tangler types.

10,000 Kg “Grand Slam” Bomb. This is an ancient, World War II weapon was used by the British Royal Air Force. Also nicknamed the “Ten Ton Tess,” about half of its weight is the cast iron casing. It was designed to penetrate up to 40 meters in the ground or into 20 meters of concrete before exploding. 

Produced between 1944-45, some 99 Grand Slams were built and 42 were used against hardened targets such as submarine pens,railway bridges, costal batteries and viaducts that had survived previous bombings. With 6.5 tons TNT equivalent, it caused mini earthquakes. The explosion could form a camouflet (cavern) while shifting ground could undermine a target’s foundation.

Massive Ordnance Air Blast (MOAB) Bomb. One of the largest conventional bombs ever made, the GBU-43 weighs about 10 metric tons and contains 8,164 kilograms of explosives. This bomb does not penetrate into the ground. When used, its explosive air blast is the equivalent of 11 tons of TNT. It has a blast radius of a mile wide. So massive – it is 9 meters long and 103 centimeters in diameter – it had to be pushed out of the back of a C-130 cargo plane rather than delivered by a bomber. The reported cost of the weapon in the mid-2000s was $170,000.

A Frontier equivalent bomb would use more advanced explosives so it can weigh 2.5 metric about tons.

Retarding Devices and Targeting Equipment

The bombs presented in “Tanks a lot!” of Dragon Magazine and even Larry Moore’s story on vehicle combat in issue 15 of Star Frontiersman Magazine appear to be unguided weapons. Also known as dumb bombs – or free-fall, or gravity, or even iron bombs – these weapons simply follow a ballistic trajectory from the aircraft to the ground. They do not have any kind of guidance system other than the fin assembly on the back.

Some bombs will be equipped with some sort of retarding device such as a drogue chute or a fin-retarder. These devices slow the forward momentum of a bomb after its release. This is especially important when anaircraft is dropping it from a low altitude. Retarding devices are also used to prevent the possibility of a bomb skipping after it impacts the ground before it explodes.

Some other retarding devices include the ballute. Invented by Goodyear in 1958, this is a parachute-like system. It is used by aircraft flying at high altitudes and supersonic speeds to decelerate and even stabilize a bomb during its decent. 

Dumb bombs can be converted into smart bombs with a few, though major, alterations. These include adding a built-in computer controller, an electronic control sensor, an adjustable fin assembly, and a battery to power it all. This equipment is required to use any of the advanced targeting equipment that was provided for in either the “Tanks” or Moore’s story or the vehicle computer-based gear in Zebulon’s Guide.

“When a plane drops a smart bomb, the bomb becomes a particularly heavy glider,” noted a story about smart bombs on Science.HowStuffWorks.com. “It doesn't have any propulsion system of its own, like a missile does, but it does have forward velocity (by virtue of being dropped from a speeding plane). It also has flight fins that generate lift and stabilize its flight path.”

As the bomb drops, the computer control system activates actuators that adjust the flight fins. Acting like flaps on a plane, the fins can turn the bomb in different directions.

“This adjustment process continues until the smart bomb reaches its target, and the fuze mechanism sets off the explosive.” Science.HowStuffWorks.com continued. “Smart bombs generally have proximity fuzes, which set off the explosive just before the bomb reaches the target, or impact fuzes, which set off the explosive when the bomb actually hits something.”

Targeting Systems. The most common way to target vehicle weapons, including bombs, is manual aiming, this would assume that an aircraft carrying bombs has some sort of bomb sight whether it is for dive bombing, high-altitude or a low-level drop.

The advanced targeting systems that have been introduced in Dragon and Star Frontiersman magazines and Zebulon’s guide include the Cyberlink, Eye-Weapon Coordination(EWC), and various weapons progits for vehicle computers.

Manual Targeting. The most common form of using vehicle weapons by civilians and even paramilitary units is manual targeting. This means the gunner operates the weapon by hand, lining up a shot and firing. The gunner using this system must expose himself to enemy fire but will have hard cover if the weapon is mounted on a vehicle. Skill bonuses apply when using this system.

Weapons mounted on turrets may have a telescopic or external camera system that allows the gunner to remain protected and control the weapon by a joystick (antiquated systems might be operated by a mechanical or hydraulic system).  Cost for the protected manual aiming system: 500 Credits.

Cyberlink, Vehicles. Also called a Computer Linked System, this is a direct mental hookup by the vehicle computer to a weapon to control its firing. Up to 5 weapons can be controlled by one gunner (or 3 by a driver) at no penalty to firing multiple weapons. Each weapon requires a separate link – even if they are in the same turret; this link weighs an additional 1 kilogram uses 1 SEU per turn of operation. The base chance to hit is 30 percent plus 10 percent per progit level.

The base chance to hit is 30 percent plus 10 percent per progit level. There are five Cyberlink Targeting progits available for purchase including levels 1-2, which are Type B progits; levels 3-4, which are Type C progits; and level 5, which is a Type D progit. Level 6 progits do exist, but they are considered to be military hardware, which is legally only available to the Spacefleet, the Landfleet or the UPF Space Marine Corps.

Effect: Allows the gunner to fire multiple weapons without penalty; 30 percent base chance to hit + 10 percent per computer level. Mass: 5 kilograms + 1 kilogram per weapon link. Cost: 5,000 Credits per level + 500 Credits per weapon link. Power: 1 SEUper turn per linked weapon. EWC Helmet: for each gunner, Cost: 200 Credits per helmet.

Eye-Weapon Coordination. EWC systems use a special helmet or electronic goggles that can track the movements of the wearer’s eyes. Through a complex circuitry link, it brings the vehicle’s (or powered suit’s) weapons to bear along the wearer’s line of sight. It provides the gunner/vehicle a +2 bonus for his Initiative Modifier (IM).

When the weapons are aimed at the target, the user has only to push a button, flip a switch, or pull a trigger to fire any combination of weapons. The helmet/goggles can be switched from infrared to normal vision and can be turned on or off.  On a vehicle, thegunner does not need expose himself to enemy fire because the helmet is connected to a set of infrared and video cameras. The images these cameras  receive are projected onto the inside of the helmet visor.

Vehicles normallyhave one gunner for each turret; this gunner may fire any combination of the weapons mounted on the turret in any one direction on a given turn.   

EWC gives the usera +30 percent modifier to hit. The gunner/powered suit pilot receives no additional bonuses due to weapons skills.

Effect: +30 percent bonus to hit but no weapon’s skill bonuses; +2 IM. Mass: 5 kilograms + 1 kilogram per weapon link. Cost: 3,500 + 300 Credits per EWC linked weapon. EWC Helmet Equipment: 200 Credits. Power: 1 SEU per turn per linked weapon.

Vehicle Computers. One of the key optional components of civilian and military vehicles is the vehicle computer (VC). Designed similar to a bodycomp, the VC is often mounted in the vehicle's cockpit and linked to all of the vehicle’s functions. It has 12 ports and uses the same type of power packs and processor packs as a bodycomp.

The differences in the following power packs are in their duration and amount of progits they can handle at any one time. It can be recharged but can never be used to power anything else.

Sixpack. The least powerful and most inexpensive computer power pack, it can provide power to a) one Type A or Bprocessor pack and six progits, or b) one Type C processor pack and four progits. The sixpack lasts for one month and costs 50 Credits to recharge.

Tenpack. This battery can power a) one Type Aor B process and ten progits; or b) a Type C processor and eight progits; or c)a Type D processor and four progits. The tenpack lasts for three months and costs 125 Credits to recharge.

Fullpack. This battery can power a) one Type A or B processor and 12 progits; or b) one Type C processor and 10 progits; or c) one Type D processor and six progits. The fullpack lasts for six months and costs 275 Credits to recharge.

Kingpack. The top-of-the-line power pack, it can provide power to one processor pack of any type and 12 progits. The kingpack lasts for one year and costs 450 Credits to recharge.

Processor Packs. The organizer, brain and interpreter for the entire portable computer system, there are four processor packs – types A, B, C, and D.

Program Units (Progits)

Progits are classified from A to D, the latter being the most complex and energy consuming. What follows are some of the common programs available for vehicles, please see Zebulon’s Guide for more information.

When purchasing progits for their devices, players must consider what power and processing packs they have so that the whole system is compatible (i.e., a sixpack and a processor pack type C cannot handle type D progits).

Key Vehicle Computer Progits

TypeA

Dis-Viz. Also called a heads up display (HUD), with this progit, a character can have full visual readouts from his vehicle computer with the information projected onto the windshield, dashboard monitors, or even into a helmet. Cost: 150 Credits.

Type B

Comp-Voice Command. This progit combines the functions of Audio-Act and Comp-Talk into one unit. Cost: 1,000 Credits.

Cyberlink Targeting Level 1. This progit must be used in conjunction with Brain-Link and the Cyberlink Targeting System. It provides the user with a +10 percent modifier to hit. Cost: 1,000 Credits.

Cyberlink Targeting Level 2. A more advanced targeting progit for the Cyberlink system, it provides the user with a +20 percent modifier to hit. Cost: 2,000 Credits.

Dis-Map Navigation. This progit must be used with Dis-Viz and contains multiple maps – or can link with a city or planetary computer – to display every explored area in the Frontier. It can show overall views of continents or zoom in on any locale for more specifics. It will show all known roads, streets, forests, navigational hazards, etc. Cost: 1,500 Credits.

Holo-Map. (Must be used with Dis-Viz and Dis-Map.) This progit is a sophisticated holographic program that enhances the Dis-Map by showing a three-dimensional view of a specific area map. Holo-Map progits also come in thousands of types that will interlink with their Dis-Map counterparts. Cost: 700 Credits.

Type C

Brain-Link. This progit comes with a miniature cortex coordinator that must be surgically implanted into a pilot’s brain. Once implanted, it can transmit and receive simple messages straight from the brain.

This progit,  when linked to certain other progits, can perform acts at incredible speeds (i.e.,using a Prog-Switch progit and mentally switching devices on and off). Cost: 3,000 Credits plus 1,500 Credits for the implant and major surgery.

Cyberlink Targeting Level 3. For use with the Cyberlink Targeting System, it provides the pilot with a +30 percent modifier to hit. Cost: 4,000 Credits.

Cyberlink Targeting Level 4. For use with the Cyberlink Targeting System, it provides the pilot with a +40 percent modifier to hit. Cost: 8,000 Credits.

Type D

Cyberlink Targeting Level 5 . For use with the Cyberlink Targeting System, it provides the pilot with a +50 percent modifier to hit. Cost: 16,000 Credits.

Cyberlink Targeting Level 6. This progit is only available for the UPF Spacefleet, Landfleet or Space Marine Corps. It is used with the Cyberlink Targeting System; it provides the user with a +60 percent modifier to hit. Cost: Notavailable for public purchase; estimated price 30,000+ Credits.

Master-Comp. This progit performs the same function as a bodycomp Master-Comp and must be used with Audio-Act and Comp-Talk or Brain-Link. This progit ties all other computer programs into a unified whole. The biggest advantage is its ability to receive conditional orders from all other progits to follow astandard operating procedure.

The Master-Comp progit is so complete that the driver can instruct it in simple terms and if it has any questions it will ask the character. It takes the place of two progits. Cost: 5,000 Credits.

Mind-Mount, Dropped Ordnance. This progit must be used with Brain-Link. It is for use with smart bombs. The character can aim such bombs, when dropped during the same turn at the same target. The character must already have the Dropped Ordnance Skill to be able to use this progit. Normal modifiers for range, movement, and size are ignored! Only the character's skill level is used. Cost: 3,250 Credits.

Tactical-Analysis. (Requires sensor package). This is an advanced roboprog that has been adopted into progit for vehicle computers. If the driver/pilot can take a turn to survey its surroundings once every minute (once every ten turns), the program allows him to receive a +20 percent modifier to detect hidden targets; for the following five turns, the pilot also receives a +10 percent chance to hit.

The driver/pilot can also transmit this information to other units with compatible equipment so they can boost their to-hit numbers by +10 percent. Cost: 1,000 Credits.

Aerial Attack Vehicles

Explanation of Large Bomb Chart

The extra blast areas are there to provide a referee with extra flexibility in determining how far out the damage spreads from an explosion. As in the case of a “Grand Slam” or MOAB bomb being deployed, you would use all eight blast areas. But for smaller explosions, for example, the referee may decide he only needs to extend the blast area out to the fifth or sixth damage zone.

The terrain of an area may also shape the zone, such as large hills, or a mountain top being between the characters and a blast.

Primary Blast Area. This is ground zero for the explosion where it will do the most damage. Depending upon the amount of damage, objects may be pulverized.

Secondary Blast Area. Characters and objects within this area take half damage, though it may still be very well lethal no matter what saving rolls are made. The blast radius is determined by multiplying the primary radius by 1.5.

Third Blast Area. Characters and objects within this zone take 25 percent damage. Again, this may still prove to be lethal. The blast radius is determined by multiplying the primary radius by 2.

Fourth Blast Area. The damage is 10 percent of that within the primary zone or a target takes heavy damage and is stunned. Heavy damage could be 10d10 to 25d10. Any surviving characters and robots would be stunned for 3d10 minutes. The blast radius for this zone is the primary radius multiplied by 4.

Fifth Blast Area. The damage in this zone is 1% or heavy damage and stunning damage, which is defined above. The blast radius for this zone is the primary radius multiplied by 6.

Sixth Blast Area. Characters and objects in this zone take medium damage and are stunned or light damage and are stunned. Medium damage is 6d10 to 8d10 and are stunned for 1d10 minutes. Light damage is 2d10 to 4d10 and stunned for 3d10 turns.

Seventh Blast Area. Characters and objects in this zone take light damage and are stunned (as defined above) or are stunned for 2d10 turns.

Eighth Blast Area. Characters and robots within this zone take stunning damage for 2d10 turns.

Family of Scatterable Mines (FASCAM). FASCAM is the term for a range of systems to rapidly deploy mines. These can be used to directly attack enemy formations or to place them down ahead of time to serve as an obstacle to adversaries. Some systems can be delivered by artillery or rocket launchers.

Some FASCAM minefields – at least those produced for the Landfleet and most Frontier planetary militias – are meant to be temporary. They are set to self-destruct after 1-20 days, depending on how they are set. Typically the mines can be equipped with radio receivers so they can be remotely deactivated so they can be collected and reused.

Below are a few examples of the aerial-deployed FASCAMs, though referees can design other types.

Gorgon FASCAM. About the size of a 30 kg bomb, this is a set of small, anti-personnel fragmentation mines (4d10 damage, 2 meter radius),with type 2 pressure sensors (50% chance to-hit). The gorgon can be dropped from low altitudes – at least 20 meters from the ground. It deploys 125 mines over a 25-by-25 meter area, with an average of 5 mines per 5-meter square. These mines will lay opening on the surface.

Orthrus FASCAM. This system is about the size of a 100 kg bomb. It scatters a set of 300 small anti-personnel fragmentation mines (see above), and 120 small anti-vehicle mines with type 3 contact sensors (60% to-hit) that do 5d10 points of damage. It will scatter these mines across sixty 5-by-5 meter squares in a roughly circular pattern from the center. It will have an average of 5 anti-personnel and 2 anti-vehicle mines per square. Most of these will be laying openly on the ground.

Shedu FASCAM. This is the size of a 100 kg bomb. It will scatter 16 Grasshopper mines with fragmentation warheads (8d10) and level 4 proximity sensors (70% chance to-hit). These mines will spread over sixteen 5-by-5 meter squares in a roughly circular pattern from the center.

Daksha FASCAM. The size of a 500 kg bomb, the Daksha FASCAM will scatter 150 normal fragmentation mines with type 2 pressure sensors (8d10damage, 50% to-hit). It will also disperse 16 grasshopper and 16 leapfrog mines with level 4 proximity sensors (70% to-hit) and fragmentation warheads. The fragmentation mines will go across fifty 5-by-5 meter squares, with an average of mines per square. The grasshoppers and leapfrog mines will be spread over this area too.