Maximum speed of an unarmored Traveller spaceship.
Assumptions/data:
The STRIKER armor rating of an unarmored Traveller spaceship is 40 (errata, 2nd edition STRIKER Book 2, p.41).
STRIKER says that 1 demo point equals the explosive power of 1kg of TNT (Striker Book 2, p. 26).
Detonating 1 kilogram of TNT gives an energy of 4.18E6 Joules.
The kinetic energy (KE) of an impact is given by the formula:
KE(in Joules) =(.5)x(mass of object in kilograms)x((velocity of object in meters/second)squared)
which can be solved for the velocity as:
Velocity of object (in meters/second) = Square root of (KE/(.5)x(mass in kg))
The mass of the biggest dust particle is set at 0.0001 kilograms (0.1 grams). Note that the average mass of interplanetary dust particles is much, much smaller than this, around 0.000000001kg.
For simplicity, 1-G of acceleration is set to 10 meters/second squared.
OK, here we go....
To be safe from any damage a STRIKER vessel must have an armor rating at least 5 greater than the penetration of the weapon. So an armor-40 hull can withstand a penetration-35 weapon. To get a penetration of 35 you need 3 demo points or 3kg of TNT. So that's the maximum explosion an armor-40 hull can withstand.
3kg of TNT gives you 1.254E7 Joules of energy. Putting this into our formula for velocity gives:
Velocity (m/s) = square root of (1.254E7)/(.5)x(0.0001)) = 5.0E5 meters/second, or roughly 500,000 meters per second, or 500 kilometers/second, which works out to about 0.167% of lightspeed. A Traveller ship accelerating at 1-G will reach this speed in about 13.9 hours.
Note: Ships with factor-1 armor can safely reach about 2.26% of lightspeed, or about 6780 kilometers/second. A ship armored to factor-15 can safely reach a maximum speed of about 60% of lightspeed.
Now let's look at Book 2 travel times. According to what was just calculated, a 1-G ship can accelerate in a straight line for almost 14 hours before it gets to its maximum safe speed. However, the Book 2 travel times all assume a turnover at the halfway point and constant deceleration to the endpoint. A 1-G ship is said to take 17.6 hours to reach safe jump distance from a large gas giant, so even this will not cause an unarmored ship to reach its max safe speed, as this only implies 8.8 hours of acceleration. However, any further distance on the Book 2 table (journeys to near neighbor worlds or further) would require that the 1-G ship stop accelerating after 14 hours and coast until it gets close and then have 14 hours of deceleration. This would increase the travel time quite a bit and make insystem microjumps more attractive.
It only gets worse for unarmored ships with higher acceleration. They will reach the max safe speed even faster and so have longer coasting times. A 6-G ship would reach max safe speed in little more than 2 hours of acceleration and would have to coast even when trying to reach safe jump distance from a small gas giant. This seems inefficient. I would think that ships of higher acceleration (say, 3-Gs or higher) would have reinforcement on their front and rear hull aspects to allow safe use of their higher acceleration. The longest travel distance given the Book 2 table is 1 billion kilometers. A 6-G ship covers that in 2.9 days. Let's round that up to 3 days so it was accelerating for 1.5 days. At 6-Gs over 1.5 days you get to a speed of 7,776 kilometers per second. To withstand a dust impact at this speed you need just over factor-1 armor.
I suspect that ships of 3-G acceleration and higher have the equivalent of factor-1 armor on their bow and stern aspects.
Code:
Max speed tables:
V=sqrt(KE/(0.00001)
HG STRIKER cm Demo KE V V
armor armor steel points (joules) (m/s) (%c)
0 40 33.6 3 1.25E+07 5.01E+05 0.16693312
1 60 190 550 2.30E+09 6.78E+06 2.260285134
2 64 269 1550 6.48E+09 1.14E+07 3.794440377
3 67 349 4000 1.67E+10 1.83E+07 6.095535707
4 70 453 27500 1.15E+11 4.79E+07 15.98262946
5 72 539 27500 1.15E+11 4.79E+07 15.98262946
6 74 640 27500 1.15E+11 4.79E+07 15.98262946
7 76 761 100000 4.18E+11 9.14E+07 30.47767854
8 77 830 100000 4.18E+11 9.14E+07 30.47767854
9 78 905 100000 4.18E+11 9.14E+07 30.47767854
10 79 987 100000 4.18E+11 9.14E+07 30.47767854
11 80 1080 375000 1.57E+12 1.77E+08 59.0197707
12 81 1170 375000 1.57E+12 1.77E+08 59.0197707
13 82 1280 375000 1.57E+12 1.77E+08 59.0197707
14 83 1400 375000 1.57E+12 1.77E+08 59.0197707
15 84 1520 375000 1.57E+12 1.77E+08 59.0197707
16 85 1660 375000 1.57E+12 1.77E+08 59.0197707
17 86 1810 500000 2.09E+12 2.04E+08 68.150161
18 87 1970 500000 2.09E+12 2.04E+08 68.150161
19 88 2150 500000 2.09E+12 2.04E+08 68.150161
20 89 2350 1000000 4.18E+12 2.89E+08 96.37888197
21 90 2560 1000000 4.18E+12 2.89E+08 96.37888197
HG Velocity
armor (percent lightspeed)
0 0.1669
1 2.2603
2 3.7944
3 6.0955
4 15.983
5 15.983
6 15.983
7 30.478
8 30.478
9 30.478
10 30.478
11 59.020
12 59.020
13 59.020
14 59.020
15 59.020
16 59.020
17 68.150
18 68.150
19 68.150
20 96.379
21 96.379
... ...or did you mean that there is nothing suggesting a deflection field is at work? As mentioned I'm pretty sure there is mention somewhere in canon.
