CLASSIC BATTLETECH CATALYST game labs

I'm not much of a talker but I thought I'd post this here, many of you have noticed that I have been posting some fighter performance specs, well here's most of the ones I have in one group with some commentary on them.

I allways wondered how good CBT fighters where, how fast they could go, their range and endurance. So a few years ago I started working them out myself while it's not to hard to do them, I only really do this when I'm the mood so progress has been slow, and that I had to redo a fair amount of them when I learned some new things that changed a lot of what I had done at that time. 

That said CBT fighters are fairly impressive over all.
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Edit: Up Dated specs are posted in post 4
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To start many fighters could carry 20 or so tons of bombs but doing so drops their speed down to 700KPH or less. So I decided to put a over all limit on speed of not to go below a 3/5 in speed. Though this would "limit" the pay load some what. though interstingly the over all range would not change as it turns out that each fuel point is about 6km in range at low altitude (or the 5 tons of fuel a fighter typical has would net you a range of 2,400km) though this dose not work at high altitude as there are speed limits up there.

As you can see the "Iron storm" can reach mach 1.77 at sea level and it's maximum speed in an atmosphere is mach 11.6 at 72,000 meters (~236,000feet).It's flight time is 66 minutes with internal fuel though this can be extended by flying slower (though the overall range dose not change). As for engine power well to compare it with a real life rocket engine the F-1 (of saturn rocket fame) has a power of 6,770kN at sea level. Also the RS-68 (Delta IV) is rated at 2,900kN at sea level and 3,300kN in space.

Well here we have the Hot rod fighter (which looks like a door wedge). It's low altitued speed is phenomenal at mach 3.2, It can't fly for very long at that speed but it can go some where in a hurry.

manages the same range as the Seydlitz but gets a little better range due to it's slightly larger external payload.

This is pretty much a generic fighters performance is like. The range at high altitued with droptanks is very good, 10 times the ferry range of a F-22 Raptor.

When you want to reach out and touch some one there is not much better than the Slayer. It can fly all the way around the world with fuel to spear. If you put a 5 ton bomb load on it with 5 tons of external fuel you can still fly all the way around, as it still has a range of 41,000km (40,075km for the Earth). 

Pretty much a standerd heavy fighter, though as you can see the internal fuel range is very smilier to most other fighters at some 2,375km which surprised me.

Your typical heavy fighter.



Despite it's slow speed the Raubvogel has a desent range dispite it's low fuel bunkerage.

Though I do a few conventional fighters as well, the Meteor has a fairly impressive range for a conventional, like the Slayer it can reach around the world though not with a bomb load.

 
Need a few support aircraft as well. A bit slow but it's quite capable (though I only gave it a speed of 6 when it can reach a speed of 7 or 1260 kph which is above mach 1... ) that fusion plant gives it a unlimited range. Though I don't think the crews would be happy to spend more than a day or two.

While it's faster speed makes the Stork a better tanker then the Mosquito the Stork ironically has a rather short range.


Well Need to do a Clan fighter.

Well there they are, If any one wants to know more or have a fighter/smallcraft you would like to see, well you can ask...
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Things I would like to add at some point
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1: A climb rate would be usefull
2: Turnning Radius for high and low altitueds.


PS: The low altitued ranges is based off the capital scale as I find it rather odd for a fighter to have such ridiculously short ranges when at the same time it can have "incredable ranges" just by climbing a few km up. Though this dose not mean it can not use the fighter scale fuel usage when in combat at that level, IIRC combat dose drain your fuel levels quite fast (or faster than when just flying around).

Yes as you can see CBT craft are generally Superior to real life craft. Though real life aircraft can reach speeds of ~2000 kph at low altitude with accelerations of only about 1G. But few real world aircraft can fly where CBT aircraft can or go as far with the amount of fuel they carry.


Thought I do a few Small Craft so see what thy can do.


Now I am not happy with how CBT has treated it's small craft, many of them have crazy things put on them even though they may not fill that role.  -see below.
For the KR-61 is obviously a long range shuttle so I would expect it to have a long range, If small craft can carry external ordinance then here's your long range bomber, It can fly all the way around the world and then some though it may take up to 33 hours with a full bomb load...


Now this one irks me to no end, it's only got 3 tons of fuel and as you can see it's very short ranged but has full crew cabins even though it has a max range of only 1.6 days at 1G. It's also got a much smaller cargo capacity than what it's fluffed to have (but that's a issue for all small craft) still you could stuff in almost 2 platoons of BA, a Light tank or APC/Scout tank or 280 infantry. Though it's fluffed to carry tanks like the Rommel and Patton (or any thing up to 65 tons)...

finally a few support aircraft

Need to move that Atlas but don't have a dropship around? Well here you go. It has a surprisingly good range at altitued with decent speed. Though amusingly it has a 3 ton kitchen and "bathroom" unit for the 32 passengers and crew even though most flight would not last more than a few hours. There is a passenger configuration that holds some 700 passengers and some 50 tons of cargo.

The so called "King Karnov" it dose not have all that great of a range but it dose hold more than twice the cargo than a regular Karnov and at a much higher speed (6 times in fact). While it's not armed or well armed nor dose it have a great range, it can deliver a 76 ton paylode out to about 375km and back in about an hour, Which would take a standard Karnov 2 hours to reach with a 6 ton payload (or 4 hours and 21 minutes with a 36 ton payload).

Well sence my last post here I have refind and considerbly updated my listings, as well as added a few more. I might remove some of the older ones.... If you guys think I should











14 tons fuel with 8 tons bombs range 40,320km

The Samurai is a Terran Hegemony aerospace fighter not DC, and also you need to correct various spelling errors, ect. yes I like to see a updated version, and the ground vehicles eventually.

Very nicely done, and it goes to show how truly high-performance ASFs are.  One additional thing I'd consider adding is a quick and dirty delta-v figure.  Each ton of fuel gives you 300 m/s delta-v, which adds up.  Compare Voyager 1's 17.46 kmrs (about 58 hexes/turn) and the number of years and gravitational assis maneuvers it took to get there.  An aerospace fighter could match that on less than a ton of fuel, in 58 minutes at half a G, or 29 minutes at a full G of acceleration.

Well here is a few more Clan fighters (with three more in the works)

As promised a few more Clan Fighters, and as some asked the Vandal. (Boy it's a fast sucker)

The Numbers are for entirely atmospheric flight only, as like you said any Aerospace fighter can climb above the atmosphere and have basically unlimited range. Though any Coventinal and fixed wing aircraft do not have that ability.

As for LOS 12m of the ground gives about 12km of LOS.


Well I don't know if this is applicable but this UHF LOS calculator gives 550km for 18km altitude and 780km for 36km altitude
http://www.qsl.net/kd4sai/distance.html

Well it makes sense that the dropship can go that fast, seeing as it needs to attain escape velocity from the average world...

Lt Nebfer, keep up the good work.

You do realize that your range and speed figures are completely wrong and generally meaningless, right?

Because their speeds vary at different bands on the high altitude map, as does their range, and any ASF has an effectively unlimited range at orbital speed (which varies by planet) because they can hop into orbit on a very limited amount of fuel and then drop back into the atmosphere, which is the most efficient use of fuel and the way they make any long distance movement.  Their endurance is effectively limited only by crew endurance.  The conventionals can be pinned a little more effectively, yes, but it's still all a guess.  In addition, you can't provide a fixed Mach number - the speed of sound is dependent on air pressure, which varies by altitude, overall atmospheric temperature, atmospheric composition, planetary size, and gravitation.  (For that matter, all of those factors will affect performance to some extent or another.)  All you're really doing is speaking about the speed of sound at sea level on Earth, which is not relevant in beyond 99.9% of cases in BattleTech.

And your "interstellar range" is, to be perfectly blunt, crap, and it's crap on multiple levels.  First of all, it's not interstellar range.  The range you provide on the Seydlitz can't even make a round trip to the Moon, and no ASF is ever going to manage a real interplanetary mission on its own.  They have neither the fuel nor the crew endurance to do it properly.  Second, it doesn't factor in the fact that unlike BattleTech, in real life, you make a sustained burn, then coast and later on make a deceleration burn.  The range is interstellar in a very technical sense, since they have the acceleration and fuel reserves to reach escape velocity relative to not only the planet they're based on, but the entire system; however, that capability is purely theoretical and never used.  There's no realistic way to quantify that and the number you're citing is meaningless.  What you should be providing is their delta-V or burn endurance, both of which are useful numbers.


I'll give you that (and this is the only time I'm going to agree with you here, so savor it), but you're sounding like all of this is completely authoritative, which it most assuredly is not.  You're throwing numbers around without actually thinking about all the factors that affect them and whether or not they're realistic values.  This is, at best, a rough guesstimate.  And in the process, you're misleading people into thinking this is anything other than a rough guesstimate based on approximation and very, very grainy values.


First, don't mix speed and velocity in the same sentence, they are not interchangeable; beyond that, it looks sloppy.  Pick one and stick with it.  I'd suggest speed, since we're assuming straight flight, meaning direction is irrelevant for the topic at hand.

Second, we're running into that whole "for the sake of the game's mechanics" problem I'll talk about below.

Third, that's not 400 minutes of flight time.  It doesn't magically get into the air with 400 points of fuel at top speed, which means you're not accounting for acceleration, altitude changes, launch, or landing.  Given that all of these do require a non-trivial amount of fuel, the equivalent of accounting for them with unicorn farts and fairy dust isn't going to fly.

Fourth, as noted before, any ASF's endurance in flight is limited not by their fuel, but by their crew, in a purely theoretical sense, and operational needs are going to be very dependent on the situation at hand.  The flight time number doesn't actually tell you anything useful.


We don't know what their service ceilings actually are, we just know what they are for game purposes.  That is not the same thing.  By the game rules, a  C-47 can reach near-supersonic speeds and climb up to 35,000 meters (over four times its actual performance ceiling), which is absolutely ludicrous, but your figures don't account for the fact that the game's mechanics are (deliberately) very grainy and don't worry about "small" details like that.  Also, the actual orbital boundary and altitude of various rows in the high altitude map should also be dependent on planetary conditions, but guess what, it's not.  Oh, yes, while we're on this, the same problems apply to atmospheric speeds - the game is completely indifferent to aerodynamics, relying purely on thrust.  You can't produce realistic numbers out of that in an atmosphere, as two objects with the same thrust will have different speeds in the air based on their aerodynamics.

Finally, external ordnance is not a fixed mass and doesn't actually relate to the laws of physics.  While tons is traditionally used there, it's used as a game term roughly equivalent to "spaces" or "slots", not a designator of mass.  If it was, an Arrow IV round wouldn't require five "tons" to carry, as it's a 200kg rocket of the same cost and mass as a ground-fired version.  At the same time, you could hang five TAG pods, or 25x the mass.  And don't try the aerodynamics dodge, or we wouldn't be able to carry these things across the orbital boundary without them being torn off or otherwise destroyed.  In other words, quit throwing that out like it's a physics term, it's not in this case.

*looks at Nebfer's long post...*

 

Yay! Someone gets it! Stuff like this is only for those fun things giving us fun numbers, and is not meant to be taken
like a serious engineering discussion...If these were serious, the people discussing them would be rich from the
military contracts they are getting giving the military ASF, KF Drives, and Battlemechs.

It is a game..some people like extrapolating data from the game rules..no need to rain on their parades.

Then I sugest you read up on Tech manual and Tac ops, both list Bombs as 1 ton each. As such a 100 ton fighter per the rules can carry up to 20 tons of external ordnace.

I also know that missiles are a lot bigger and bulkyer than bombs which are more dense.

Case point F-15s can only carry eight AIM-120 missiles (1.2 metric tons) yet can carry over four metric tons in bombs.

you mean something like this?

speed of sound at sea level is 1,225 kph
speed of sound at 20,000m is 1,060 kph
speed of sound at 30,000m is 1,080 kph
speed of sound at 40,000m is 1,140 kph
speed of sound at 60,000m is 1,155 kph
speed of sound at 72,000m is 1,070 kph
speed of sound at 80,000m is 990 kph
speed of sound at 90,000m is 970 kph
Not entierly accuret but close enough for goverment work

Not to sound rude but if you wanted me to acknowledge that the numbers are a fan project and not official. You might have wanted to say so in the first place insted of dissing them out right.

You could of said something like "Hey nebfer you might want to put a disclamer as to where these numbers are coming from as some people might think these are official numbers insted of a fan project."

As you really hate the term intersteller would interplanetary* be better?. As it is this is more for the typical lay person than a serious tech document. Most of us who play the game probably do not have the foggiest as to what Delta V is but can understand what 3,000,000km is. All what it is showing is how far you can go if you did a single accel/decel burn from point A to point B with all your fuel. Now yes you could increase that range with costing but that's a random variable and difficult to calculate.

* Oddly I just remembered about this term... At the time I could only think of intersteller...


Edit:
I fell I should point out that I do have aspergers, so if I seem a bit bullheaded at times or what not... at lest you have a idea as to why that is.

I might point out that I do intend to do some Dropships once I get through the fighters, infact I have one posted allready.

Travel times to the Moon and Mars
Asuming a constent Accel/Decel burn and the fuel to use it.
Typical ASF has 5 tons of fuel internal

400,000km (earth to the moon)
.0025G 71 hours
.01G 35.5 hours
.1G 11.22 hours (jumpship)
.5G 5.02 hours (typical BT ASF has 6.66 hours of fuel at this rate)
.75G 4.1 hours
.875G 3.8 hours (in thery a typical BT ASF would have 3.81 hours of fuel at this rate)
1G 3.55 hours (typical BT ASF has 3.33 hours of fuel at this rate)
1.5G 2.9 hours
2G 2.5 hours (typical BT ASF fighter with 2.5t external fuel)
2.5G 2.25 hours
3G 2.05 hours (typical BT ASF fighter with 5t external (or 10t internal) fuel)
3.5G 1.9 hours
4G 1.77 hours
4.5G 1.67 hours
5G 1.59 hours
6G 1.45 hours
7G 1.34 hours
8G 1.25 hours
9G 1.18 hours
10G 1.12 hours
12.5G 1 hour

228,000,000km (earth to mars)
228,000,000,000 meters

.0025G- 70.6 days
.01G--- 35.3 days
.1G---- 12.55 days
.5G---- 5 days
1G----- 3.53 days
1.5G--- 2.89 days
2G----- 2.5 days
2.5G--- 2.24 days
3G----- 2.04 days
12.5G-- 1 day

Now very few fighters can carry more than 15 tons of fuel and none carry more than 20. However you could turn a ASF fighter into a flying gas tank and have it reach Mars on internal fuel and have it get there in 5 days. All it takes is about 90 tons of fuel, this is 9 times the rate of small craft.

Yes some are more technical than realistic in B-tech terms.