Hi folks,
Ok, here we go:
Here are a few areas where the MegaTrav design system is off by
orders of magnatude. These are things I would like to see
corrected in a revision of Traveller.
Fission/Fusion/Antimatter fuel requirements.
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A few days ago I put out a note about how bad the fuel
requirements for a fission reactor are. Well, I looked up the
actual figures and here we are:
The N.S. Savannah, (world's first [only?] nuclear merchantmant)
carried 49 kg of uranium fuel. According to the article, this
would power the reactor at 80%-20knots for 300,000Nm. 15,000 hrs
at 20.1MW output. According to MegaTrav rules that same reactor
would burn 7537.5 metric TONS! Now I don't mind a factor of 2
error here and there between freinds but that is FIFTEEN MILLION
percent error!
(source: Aug 1962 National Geographic "Aboard the N.S. Savannah")
Ok, now how do we revise this without throwing every traveller
fusion reactor out the door in the revision?
Answer: Simple. Fusion reactors don't burn Hydrogen, they burn
Tritium/Deuterium (hydrogen isotopes). It is present in the
hydrogen fuel but in extremely small quantities. (No I don't
have the figures with me... {Metlay?}) This could account for
the discrepancies in fuel consumption/energy output.
Jump drives make use of hydrogen for cooling as well as a power
source. Thus they need the extra hydrogen in the mix.
Advantage of this idea: Now, one could fill a starship's fuel
tanks with deuterium/tritium and have 1000+ times the endurance
for the power plant. (refined deuterium & tritium would of
course COST a lot more, but military ships could afford it.)
Of course they would still need to carry jump fuel, and dumping
deuterium and tritium into the jump drive when hydrogen will do
would be expensive! But that would explain why hydrogen was
used.
(Please note: With the above change in fuel consumption: ie
vastly reduced fission fuel consumption, fission powered
starships are indeed feasable within the MegaTrav design system.
I have put a few onto the TML and they should be available from
the TML vehicle archives. I created a minor-{major?} argument
when I pointed out that a Nuclear Damper should be able to
increase the output of a fission reactor dramatically by speeding
up the fission reaction. Anyone interested in this see the
"Highguard" Class experimental cruiser in the TML archives)
Of course this makes the anti-matter fuel consumption stuff look
absolutely rediculous... But I haven't seen anyone use it. I
tried a brief experiment and saw that a TL 16 fusion plant was
much more desirable. In any case, changing the Anti-Matter
consumption isn't going to ruin anybody's day. I haven't seen a
single design that used it.
Batteries:
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The batteries are much too expensive. I have turned out a few
Diesel/Electric submarines (using a similar system to the
recently published Wet Navy) and the subs ended up costing about
as much as a heavy Battlecruiser of the same Tech level. (a U.S.
Fleet type sub cost as much as the Graf Spee!) This was due
solely to the cost of the batteries.
Admittedly, I'm not sure of the power it stores, but the battery
in my car is about 5 liters in volume and cost me $25. Well a 5
liter battery in MegaTrav costs about 1500 Cr. Something is
Wrong here!
Ok, now the battery table is converted from Book 8 Robots. So,
I'd guess that the writers figured these were high storage/light
weight/small size/high quality batteries to fit inside a very
sophisticated electronic device.
Perhaps, there should be a chart of batteries meant for large
storage as opposed to high quality? After all, filling a
diesel/electric sub with camera batteries is going to be Quite
expensive...
Maximum Speed
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Has anybody looked at the max speed table? The thrust/weight
ratio and it's correspondance to maximum speed is WAY off. I
strongly suggest that the people revising the stuff take a look
at the actual thrust to weight ratio's of aircraft.
(all speeds below are in kilometers per hour)
Thrust/Wt Aircraft Speed MegaT COACC
..2G C-135A 965 240 240
..3G A-6 1100 360 360
..4G F-5 1700 480 480
..5G F-8 1930 600 600
..6G F-105 2235 720 720
..7G F-106 2455 840 840
..8G F-14 2485 960 960
..9G 1080 1080
1G F-15 2655 1200 1200
2G 2120 2000
3G X-15 7274 2850 3000
4G 3400 3200
5G 3840 3750
6G 4200
(Note that the SR-71's thrust to weight ratio is .3824 max speed
is unknown but around 3100 kph {Bertil?})
(The X-15 thrust/wt ratio is about 1.15 increasing to 3.3 as fuel
is burned)
(I complied a list of thrust to weight vs max speed which anyone
is welcome to, just ask)
In the light of the above, I think grav vehicles and starships
max speed should be VASTLY higher than they are. COACC's
aircraft engines have vastly exaggerated thrusts listed, and so
that the aircraft's speed comes out about right. But any 1G
merchant ship should be about Mach 2+, and any grav vehicle/ship
with an excess thrust of 3G would be about as fast as the X-15!
(Mach 6+!!)
Rate of Fire
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Wet Navy/Design and stuff. The Rate of Fire for big guns is off.
Perhaps the Ref's handbook doesn't take the loading equipment in
a turret into account, but according to what I have found about
the Bismark, and other TL 6 heavily armed ships, the ROF of a
38cm gun should be 2 rounds per minute, not 1/4; ROF of the 28cm
is also 2 rnds/min, not 1/4, and the ROF of a 20cm gun should be
3 rnds/min not 1.
This of course is only a minor quibble...
If we can hammer these out this revision would really be great!
Falicitations,
Scott S. Kellogg
PS. One extremely minor quibble: Challenge 54 gives us a whole
lot of new weapons (YEA! TL 2 Cannons at last! Yippee!) But it
doesn't give us the prices. A missile launcher weighs 110% of
weight of missile... but no cost or volume. A torpedo tube takes
up 110% of the volume of the torpedo, but no weight or cost...
Anybody out on GEnie have those figures?
PPS. The TDR folks had an idea which makes sence: Have the
chassis damage points of a vehicle be related to the weight of
the chassis. Thus a heavily armored chassis would be able to
take more low penetration damage than a light one of the same
size. (The example was one of school bus vs. main battle tank)
But I don't know much about it. {Rob can you give us a run down
on it?}
Thanks,
Mr. Scott