Environment
Hyperspace:
Open hyperspace: Thin gas and dust, trace oxygen, radical temperature shifts without warning, and strong static electric fields. Antarctic level temperatures. Occasional regions of highly excited gas which exceed 200 degrees Celsius.

Sparse hyperspace: visually obstructed by charged gas, and dust, occasional boulder sized rocks, sleet, and constant electrical thermal variations. 1 pt of damage per hour for personnel not grounded or wearing protective gear. Trace atmosphere sub-freezing temperatures.

Dense hyperspace: thin atmosphere, freezing temperatures. Dust, gravel, large boulders. Violent weather and frequent lightening, strong winds. Some large local wildlife and flora. Large amounts of plankton, pollen. 20% chance of allergic reactions per hour of direct unfiltered exposure. Causes blurred vision, itching, difficulty breathing painful congestion. Treated with basic medical care. Recovery takes place in 8-Endurancemodifier hours after exposure, or 10 minutes after treatment.

Cluttered Hyperspace: Breathable, tainted atmosphere. Large islands, boulders, gravel, and sand common. Strong winds, ice, sleet, driving rain, and strong electrical storms common. Local wildlife becomes commonplace.

Obstructed: thick, tainted atmosphere, large areas of nearly liquid atmosphere (drowning hazard). Al forms fauna and flora abundant and aggressive. Ships larger than 100 tons cannot pass through obstructed regions.
Constant strong weather, and heavy mist rain, sleet, or hail. Constant electrical activity 10% per hourof low intensity strike (3d6 personal damage) 2% per hour of high intensity strike ( 8d6 personal damage, 1 pt starship damage)

Hyperspace exposure affects as radiation: crew must be treated (difficult -2 DM) to prevent Hyperspace Sickness. Once exposure reaches lethal levels crewman no longer able to safely function in Normal space due to metabolic changes, if returning to normal space suffers same process in reverse.

Ship with hull, or structure damage are vulnerable to intrusion by Local Fauna, occurs any time a one is roll on either die of a 2d6 roll.

Computers, and AI must be shielded from Hyperspace exposure, Hardened computer, or protective gear for AI required if exposure to hyperspace environment likely. Vacc Suit, and Hostile environment suits, as well as combat armor and battledress mounted computers considered shielded. All electronics require shielding devie+20% to base cost.
Hyperspace fauna can be eaten, but causes minor hyperspace poisoning without proper supplements. Supplements 25 cr per week supply.

All regions of hyperspace considered micro gravity environments. Zero-gee training, grav belt. or thruster packs required for safe movement. In obstructed hyperspace moment by “swimming” possible. However -2DM on all movement tasks imposed by unfamiliar environment.

Open Hyperspace requires vacc-Suit
Sparse Hyperspace requires Hostile Environment suit
Dense, cluttered, Hyperspace require protective clothing equal to cloth armor+ breather
Obstructed hyperspace requires only a breather to survive.

Starships
Weapons changes
Beam Lasers: same cluttered Hyperspace acts as 1d6 sand. Obstructed Hyperspace acts as 3d6 sand.
Pulse lasers: replaced by plasma cannon, same statistics and rules. Affected by sand 10% per point of sand deployed of premature detonation of plasma bolt.
Particle beams: affected by hyperspace dust, reduce damage by 1d6 pts per range band beyond Short, not radiation damage in Hyperspace due to filtering effect of dust and gas.
Missiles: require lock on, lock on can be established by friendly ship with functional sensors and comm system. Friendly ship suffers -2Dm to lock on for another vessel.
Railguns/E-mag cannon: can be used beyond short range, suffer -2 cumulative Modifier for each range band beyond sh
ort.
Operations:
Ship may skim fuel in hyperspace, requires either dense or heavier environment, Skimming may continue during normal travel in these conditions. In open hyperspace, ship must dedicate ¼ of travel time to skimming per day….reduce distance traveled by 25%

Starship Damage:

First H-drive hit disable Static barrier, allowing direct contact with Hyperspace environment. Further hits affect drives as per rules. Static barrier repaired separately from Drives.

Hull hit has 20% per hit chance of opening hull to hyperspace, any breach allows local fauna into ship, must be repaired before return to normal space.

Hull reduced to points zero exposes a crew to hyperspace effects, and allows free access to interior of ship by local wildlife. Ship unable to operate in Normal space without risk of damage to all crew and passenger during H-space transit. 3d6 per crewman sealed armor, or Vacc Suit protects from damage. Armor from suit applied to damage taken from transit.

Technology:

Fusion power interchangeable with Quantum resonance power systems.

Laser weapons interchangeable with low energy plasma weapons( Pseudo Plasma, Phased Plasma): when replacing a laser weapon with a plasma weapon the stats and rules for the laser weapon are identical, only the appearance and special effects are changed.

Psuedo,Phased Plasma weapons cannot breach obstructions, will deal full damage to obstruction but will not damage anything not in direct contact with obstruction.  Persons wearing armor combat armor or battle dress are affected by plasma weapons since they are in direct contact with the armor…or close enough to count. Persons in vehicles not affected by plasma weapon unless targeted directly though openings, or breaches caused by previous attacks.( -2 attack DM)

NOTE: plasma weapons that are listed in game sources function differently than the lighter weapons carried in place of lasers. They use the normal Traveller rules for plasma weapons…and are usually far more expensive/advanced.

Firearms: firearms use low impulse magnetic or gravitic systems to propel bullets instead of chemical propellants. This has no real effect on damage or range. However it allows weapons to be fired in vacuum, or non-oxygen environments. This is not the same as a rail gun, since railguns fire at much higher velocities and use a totally different projectile.

Chemical propelled firearms available, but ammo is not always available, or must be custom manufactured.
Rocket propelled weapons: RPGs and other self-propelled projectiles use compact short burn high powered gravitic systems for propulsion. They can be fired in enclosed spaces, or in vacuum, r potentially flammable environments.

Starship Drives:
All ships with Gravitic system have acceleration compensation and artificial gravity. However they also make use of Plasma ramjets/turbofans. Which provide thrust while pure gravitics allow for low speed maneuver only.( 1 Gee max) any ship with no more thrust than 1 Gee is assumed to be a pure gravitic drive.

When in vacuum, ships must burn fuel to use more than 1 Gee thrust. Reducing fuel by 1 ton per day per Gee of thrust over 1 gee. (Minimum 1 ton) spent at high gee burns. Starships can burn through fuel much faster, and must skim fuel or refuel from a processor to maintain more than one Gee thrust for any length of time.( short term burns use 0.05 tons per hour, per gee of thrust)
Ships which cannot skim fuel, or which operate in Vacuum/real space for extended periods must have tankage for extra fuel, burn reactor fuel, or maneuver on gravitics alone.

If a ship has accelerated at higher gees than One Gee, and does not have sufficient fuel for a braking burn, it must use 1 Gee thrust to slow. Taking (Hours accelerated Gees over 1) to slow down to a stop…it may be simpler to call for help than figure out how long you need to stop…

Aerodynamic braking, and gravity braking can be used but are extremely dangerous, and difficult. Pilot (10+) and Astrogation (10+) required to slow to safe landing speeds. Or ship takes 3d6 points of damage, damage is not reduced by armor. Rolling a double 1 on either rolls indicates crash landing, ship disabled hull reduced to 0, and structure reduced by 3d6, if structure reaches zero the ship crashes and is wrecked. Crew are subject to 4d6 damage.
If both checks result in double ones…..well better luck with your next character…the ship burns up on entry, then blasts a large smoking hole in the planet/asteroid they were attempting to use for braking…unless you can get to an escape pod, or small craft