TechMemo:Combat Shuttle Physics
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Star Fleet Engineering
Bureau of Starship and Starcraft Technology
Combat shuttle craft, often referred to as fighters or attack shuttles depending on their mission, are highly specialized sublight shuttlecraft intended to operate in or near atmosphere in the support of marine landings. They are also employed in a limited space-bourne roll in patrolling systems and enforcing commerce regulations.
This document gives a brief introduction to the physics of piloting a combat shuttle craft. It ignores relativity for simplicity, although this is not proper when considering craft operating at their top speeds as there are significant relativistic concerns with vehicles operating at high sublight speeds. At maximum speed, the time dilation factor for a combat shuttlecraft may be as large as 1.5. That is, something that subjectively lasts one minute for the pilot lasts one and a half minutes for the outside would.
Constants and Formula
| Type | Maximum Acceleration | Maximum Speed |
| F-4 | 240 km/s² | 0.73 c |
| F-15 | 250 km/s² | 0.75c |
| A-111 | 205 km/s² | 0.70c |
| RF-4 | 240 km/s² | 0.75c |
| v = at | velocity is equal to acceleration times time valid for constant acceleration |
| x=0.5at² | position equals one half acceleration times time squared valid for constant acceleration |
| c (Speed of Light) = 300,000km/s (Approximation) |
| 1 light-minute = 18,000,000km (Approximation) |
| 1 light-second = 300,000km (Approximation) |
Note: The speed of light is more like 299,800 km/s, but 300,000 kps makes a good approximation for most simple calculations and, for simplicity, is used in all of the following calculations.
| Photon torpedo: 1.1kg of antimatter in a standard warhead. |
| Earth orbits 149,600,000 km (1 AU or 8.31 light-min) from the sun. |
| Mars orbits at 227,940,000 km (1.5237 AU or 12.66 light-min) from the sun. |
| Jupiter orbits at 778,330,000 km (5.2028 AU or 43.24 light-min) from the sun. |
| Pluto orbits at 5,913,520,000 km (39.5294 AU or 328.52 light-min) from the sun. |
Fighter Speeds
| F-4 | 0.73 c | 912.50s (15min, 12.5s) |
| F-15 | 0.75c | 900.00s (15min) |
| A-111 | 0.70 c | 1024.39s (17min, 4.39s) |
| RF-4 | 0.75 c | 937.50s (15min, 37.5s) |
| F-4 | 0.20c | 248.78s (4min, 8.78s) |
| F-15 | 0.25c | 250s (4min, 10s) |
| A-111 | 0.17c | 300s (5min) |
| RF-4 | 0.20c | 249s (4min, 9.3s) |
Fighter Relative Accelerations
For an F-4 and F-15 starting from rest and accelerating at maximum acceleration they travel the following distances in the indicated times with the shown separation:
| F-4 | F-15 | separation | |
| 10 s | 12,000 km | 12,500 km | 500 km |
| 30 s | 108,000 km | 112,500 km | 4,500 km |
| 15 m | 97,200,000 km | 101,250,000 km | 4,050,000 km |
For an A-111 and F-15 starting from rest and accelerating at maximum acceleration they travel the following distances in the indicated times with the shown separation:
| A-111 | F-15 | separation | |
| 10s | 10,250 km | 12,500 km | 2,250 km |
| 30s | 92,250 km | 112,500 km | 20,250 km |
| 15m | 83,025,000 km | 101,250,000 km | 18,225,000 km |
Travel Times within a System
As a fighter increases speed and approaches the speed of light, time passes more slowly for the pilot than for the surrounding universe. At 0.4c (120,000km/s) there is about a 10% time dilation. At maximum velocity of 0.73c (219,000km/s) there is about a 45% time dilation. That from the perspective of someone on Earth (or on a starship at warp) sees the F-4 travelling at 0.73c take 10hrs 47min 5s to reach Pluto, while the pilot only experiences 7hrs 26min 16s of time passing. Because of this, normal travel is restricted to well below 0.4c.
An F-4 leaving earth from rest using max acceleration up to cruise speed would pass:
| Mars in 903s ( 15min 3s) |
| Jupiter in 5489s ( 1hr 31min 29s) |
| Pluto in 48282s (13hr 24min 42s) |
An F-4 leaving earth from rest using max acceleration up to max speed would pass:
| Mars in 808s ( 13min 28s)† |
| Jupiter in 3327s ( 55min 27s) |
| Pluto in 26776s (7hrs 26min 16s) |
| †still accelerating when it reaches Mars |
Note: Remember that if the planet is the destination the fighter
would have to slow down on approach which would increase the
travel time.
Torpedo Hits on a Fighter
| At direct hit to 6.36km | the craft will be destroyed |
| At 6.37km to 18.72km | the POIS system will be cripled |
| At 18.73km to 23.10km | the POIS will automatically engage |
| At 23.11km to 34.43km | the craft will be damaged |
| At 34.44km to 50.42km | the shields will be drained 100% but the craft undamaged |
| At 50.43km to 85.44km | the shields will be drained 75% but the craft undamaged |
| At 85.45km to 101.45km | the shields will be drained 50% but the craft undamaged |
| At 101.46km to 137.72km | the shields will be drained 25% but the craft undamaged |
| At.137.73km and greater | the shields will not be appreciably depleted |
| At direct hit to 6.00km | the craft will be destroyed |
| At 6.01km to 17.67km | the POIS system will be cripled |
| At 17.68km to 21.81km | the POIS will automatically engage |
| At 21.82km to 32.66km | the craft will be damaged |
| At 32.67km to 48.43km | the shields will be drained 100% but the craft undamaged |
| At 48.44km to 81.74km | the shields will be drained 75% but the craft undamaged |
| At 81.75km to 96.45km | the shields will be drained 50% but the craft undamaged |
| At 96.46km to 130.64km | the shields will be drained 25% but the craft undamaged |
| At 130.65km amd greater | the shields will not be appreciably depleted |
A quantum torpedo is a weapon used against a capitol ship. It has the same warhead as a photon torpedo, but a directed explosion. If you are on the focusing side of a quantum torpedo, then multiple the range of damage, etc., by 1.4. If you are on the non-focusing side, multiple the damage ranges by 0.75.
A photon torpedo has a yield slightly larger than a 47 megaton nuclear device. Simply multiply the effected ranges by the ration of the explosive power of the blast. For instance, a 20mt nuke would have an area of effect 20/47 (~0.426) times that of a photon torpedo.
Phaser Hits on a Fighter
Phasers work differently than torpedos. They need to hit the ship. The determining factor is how long it will take for a phaser hit at a given range to destroy the ship and whether the ship targetting the fighter can track the fighter for that long or, if there has been an extended fire fight, if the ship can sustain a blast that long.
There is no good basis that I have yet found for deciding what the power output of a phaser bank should be, so these numbers are subject to change. What will not change is that a phaser produces an electromagnetic field which looses power with an inverse square law.
That is, if you double the range, you quadrupple the amount of time that the beam needs to destroy the craft. If you tripple the range, you multiple that number by 9.
For a type X phaser firing at full power from 100,000km, an F-4 would be:
- destroyed by a hit of 1 seconds in duration,
- critically damaged after 0.76 seconds,
- undamaged by a hit of 0.2 seconds in duration.
For a type X phaser firing at full power from 200,000km, an F-4 would be:
- destroyed by a hit of 4 seconds in duration,
- critically damaged after 3.04 seconds,
- undamaged by a hit of 0.8 seconds in duration.
For a type X phaser firing at full power from 300,000km, an F-4 would be:
- destroyed by a hit of 9 seconds in duration,
- critically damaged after 8.84 seconds,
- undamaged by a hit of 1.8 seconds in duration.
