Streamlined Vs. Partially Streamlined
- Thread starter BetterThanLife
- Start date
mike wightman
SOC-14 10K
You could hide it all in the bridge tonnage, which may help explain the size of CT bridges - there is a minimum amount of CG, grav plates and inertial compensators for ships of 1000t or less.
Actually, Bhoins, you're dead wrong about contra-gravity (defined as weight nullification in TNE and T4) existing in all editions. (Perhaps I'm being picayune about semantics. I don't care... you're making erroneous oversimplifications.)
T20, Striker and MT use gravitic thrust systems (not the same), and it's an option for TNE, and is a separate item in T4.
CG makes you weigh less. Gravitic thrust uses gravitic technology as a thruster.
So, the maneuver G of a CG vessel is always whatever thrust the maneuver drive has. (In TNE, that is a non-gravitic drive.)
A CT-Striker or MT air-raft design simply has a gravitic thust system... so a 5G capable air-raf has 4G's available for maneuver on earth, 5 in 0-G, 4.7 on mars, etc.
Subtle, but important difference.
Likewise, not all editions have MT's overthrusting capability. Therefore, an aerodynamic lift system is of aid especially to 1G craft.
You can put a 1G constant thrust craft into orbit - if it has aerodynamic lift, and you have a thin or better atmosphere (the requisite for aerodynamic lift in traveller; Nasa is planning on flyin aerial flying probes on mars, which has effectively no atmosphere or trace atmosphere, dependent upon edition). Start with a grounded roll (All maneuver power to forward) until you cain aerdynamic lift (now providing slightly more total G's available) giving you the ability to accellerate forward (to the limits of aerodynamics) and also lift off.
As for t20 not specifying aerodynamic lift: that was removed very late in the process. The playtest drafts specified (after it was added) that it could generate lift. Hunter's late-on change was a simplification.
In any case, under T20, Airframe designs get to use all their G's in atmosphere; PSL (only 1G) and SL (only 2G) don't. T20, page 261. Which means the patrol craft benefits highly.
as for shipboard gravity: AG takes up significant space and power under MT, TNE and T4, as do inertial compensation. Unter TNE and T4, so also does CG. CT presumes them, as does T20. Nicely non homogenous treatment...
And Bridge tonnage is only 2%, once you cross 1000Td... in CT and T20 only. Some TNE/T4 designs have bridges less than 2%; done by having a 200 Td vessel with 3 or fewer bridge crew...
T20, Striker and MT use gravitic thrust systems (not the same), and it's an option for TNE, and is a separate item in T4.
CG makes you weigh less. Gravitic thrust uses gravitic technology as a thruster.
So, the maneuver G of a CG vessel is always whatever thrust the maneuver drive has. (In TNE, that is a non-gravitic drive.)
A CT-Striker or MT air-raft design simply has a gravitic thust system... so a 5G capable air-raf has 4G's available for maneuver on earth, 5 in 0-G, 4.7 on mars, etc.
Subtle, but important difference.
Likewise, not all editions have MT's overthrusting capability. Therefore, an aerodynamic lift system is of aid especially to 1G craft.
You can put a 1G constant thrust craft into orbit - if it has aerodynamic lift, and you have a thin or better atmosphere (the requisite for aerodynamic lift in traveller; Nasa is planning on flyin aerial flying probes on mars, which has effectively no atmosphere or trace atmosphere, dependent upon edition). Start with a grounded roll (All maneuver power to forward) until you cain aerdynamic lift (now providing slightly more total G's available) giving you the ability to accellerate forward (to the limits of aerodynamics) and also lift off.
As for t20 not specifying aerodynamic lift: that was removed very late in the process. The playtest drafts specified (after it was added) that it could generate lift. Hunter's late-on change was a simplification.
In any case, under T20, Airframe designs get to use all their G's in atmosphere; PSL (only 1G) and SL (only 2G) don't. T20, page 261. Which means the patrol craft benefits highly.
as for shipboard gravity: AG takes up significant space and power under MT, TNE and T4, as do inertial compensation. Unter TNE and T4, so also does CG. CT presumes them, as does T20. Nicely non homogenous treatment...
And Bridge tonnage is only 2%, once you cross 1000Td... in CT and T20 only. Some TNE/T4 designs have bridges less than 2%; done by having a 200 Td vessel with 3 or fewer bridge crew...
RandyT0001
SOC-13
I guess they added the stats in the design sequences for CG and gravatic thrusters in editions after Classic to pacify the really hardcore gearheads (worse than me if possible). Guess they wanted Traveller to be even more 'hard' scifi than what it was before. I just assume that all ships have CG (hands and feet wavin') and not worry about it. Use whatever makes the referee and especially the players happy because the idea is to have fun role-playing and not getting bogged down in the rather insignificant details of CG, airframes, gravitic thrust, Heplar, etc.
CT took a minimalist approach.
Striker started the detailing out, and was effectively the CT vehicle design sequence.
MT integrated Striker and CT into a hybrid.
TNE altered a lot; much of that was a paradigm shift (which, courtesy of Dave Nelson, we know was intentional) in the technological underpinnings of the OTU. Technologically, TNE and T4 are a parallel universe... Specificaly, the idea that gravitics could create thrust was removed from the TNE canon universe
T4 kept most of TNE, but added back the common use of gravitic thrust.
GT uses GURPS technology (with a few limited exceptions, and a strongly chopped list above GURPS TL10).
T20 references a lot of things in specific yet still generic ways (like CG or anti-grav thrust).
We'll have to wait and see what T5 does.
Striker started the detailing out, and was effectively the CT vehicle design sequence.
MT integrated Striker and CT into a hybrid.
TNE altered a lot; much of that was a paradigm shift (which, courtesy of Dave Nelson, we know was intentional) in the technological underpinnings of the OTU. Technologically, TNE and T4 are a parallel universe... Specificaly, the idea that gravitics could create thrust was removed from the TNE canon universe
T4 kept most of TNE, but added back the common use of gravitic thrust.
GT uses GURPS technology (with a few limited exceptions, and a strongly chopped list above GURPS TL10).
T20 references a lot of things in specific yet still generic ways (like CG or anti-grav thrust).
We'll have to wait and see what T5 does.
BetterThanLife
SOC-14 1K
OK I am making oversimplifications. Lets keep it simple and pick on everyone's favorite Starship. The Standard Type-S, Scout Courier. There are plenty of canon pictures of both the interior and the exterior.
THe Type-S obviously has the Engine thrust perpendicular to the plane of the ship, it is obviously not a lifting body, and it isn't equipped with wheels for a runway landing. However it obviously can and does land. It also obviously flies fine within atmospheres.
The questions are simple. What does it use for lift? How does it land? What are these engines that can be used for maneuver thrust but require no reaction mass or fuel, simply power? If the thrust is independent of the apparent direction of travel why does a ship have to turn over at the halfway point in the flight between two points under sublight drive?
While I don't have a degree in Aerospace Engineering I do have quite a few credits is design, aerospace theory and advanced dynamics. SO go ahead and get as technical or as complex as you feel the explaination requires. If I have a question it won't be at the basic level, and I am not afraid to ask questions.
Now I do know you have some flight experience. So let me ask this simple question. Does air pressure temperature and humidity affect lift that a lifting body, or wing, produces? Or to simplify the question is there a difference in stall speed between landing at LaGuardia on a hot humid summer day (Sea Level) and landing at Denver International Airport on a cold clear winter day? (Altitude about 6000 ft.)
Not just stall speed, but also fuel performance.
Higher density is lower stall speed. Higher density is usually obtained by lower altitude and/or higher humidity. Provided that the temperatures don't result in icing or fog, higher humidity provides denser atmosphere (for a given pressure) and thus more lift.
The Type S, under CT and MT, clearly has to vector the thrust, or come in tail-down. Under TNE & T4, it has to do the same, just with less thrust. Under TNE, even with the CG "Floating" at 98%, that's still going to accelerate you into a massive crunch, just not a total devastation crunch... (0.2m/s^2 still adds up to terminal velocity fast enough)
The S2 Serpent, however, can make a thrust-available or thrust off landing. (Spaceship One established heat shielding is not an absolute requirement....) It's roughly the size of a 727... and will have similar landing roll needs. But, if you have the fuel (not a given under TNE...) you can make a hybrid landing: feather in, rotate, aerodyne approach, flare to stall, touch on engines vectored thrust, lower the nose.
Takeoff: similar issues for the standard wedgie. The lifting airframe, however, can (in atmosphere) gain considerable lift bonus AND can trade forward vector for upward with pretty good efficiency. Most aircraft generate all their lift off the wings, therefore 1G lift at Std Temp, Press, Density and Gravity (henceforth STPDG) in straight and level flight at cruising speed.
Now, Airframes in STPDG situations can be safely assumed capable of 1.1G's of lift at full speed, or more. (Many don't even have a full G of thrust... if thrust is 1G+, they take forever to auto-break-over from the hammerhead stall...) At that rate, the lift generated post-flight is 0.1G, or 1m/s/s, leaving all engine thrust (2G's) for aiding. I can't do the needed math, but I know that you can optimize for somewhere around 2.1 positive g's lift this way, and maybe more. And, when high enough, you begin a rotation to transfer speed to upward climb. Not so important for the Type S2, in that only a few canonical worlds even approach 2G's.
Now, add CG into this. Now, downward force is 0.2m/s/s, so an airframe can/will throw that 1.08G (10.8m/s/s) left into upward climb... again STPDG. So it should be able to climb out at somewhere between 2.2 and 2.8G , vs 1.98G for the non-lifting Type S Wedgie.
Now, one important crunch under TNE: gravitic thrust is non-extant. (Doesn't exist at all in the TNE-OTU). Which means even more problems for both types... For lifting-airframes, it means problems only for takeoff, really. (In many cases, a direct takeoff may be more fuel efficient. Only when Local gravity is very close to the acceleration does the added lift become essential. With CG, the wings need to generate 2% optimal lift to get off the ground; think a 727 with a 200m takeoff roll... and that's the S2A design I posted to the TML many years ago.
Another consideration: a 0.9G thrust aircraft, with high lift wings, can generate up to 4 or 5 G's of effective in-atmosphere maneuver by aerodynamics. (Pipers can cancel themselves... with HL kits, they can be induced to make turns with G-loads in excess of the frame's strength.)
Airframes are a good thing. they add flexibility, in droves. Only TNE's rules provide a clear and present need for them... no-thrust landings.
(they also add potential plot complications. ForEx: the party buys a Type R off-contract for a song; she's in beautiful shape, good engines, etc... offered as is, and in an orbital yard. Problem is her landing gear and aerodyne control surfaces are frozen in a right banking climb... (and for TNE or T4, go ahead an knock out the CG, just to make it clear she's NOT a dirt-lover).
As for glide ratios: I've flow aircraft ranging from 1.8:1 (Beaver on floats with loads of drag from leftover WWII hardware, including a bomb-rack) through 23:1 (Schweitzer sailplane). The fundamental rule of landing is that you stall out when close enough to the ground not to damage the airframe. On the schewitzer, we hit ground effect after flare at abut 20m, at stall +5kts. Throwing the airbrakes on, we finally dropped out of the air (and ground effect) at stall-5kts, 250m down the runway, and rolled to a stop another 50m or so. Those last 3m vertical were not compromised at all until the aircraft finally lost ground effect and FELL 3m. Ground effect does wonderful, weird, and dangerous things.
In fact, ground effect is so profound, that an entire category of powered flight is devoted to it exclusively. THe soviets used a heavy lift airframe, designed for maximumization of ground effect, as a form of low-drag boat. (were it not for trees, it could work overland, as well.) Now, some use companies are making sporting craft in this range. They fly, but their lift is only 1G+ while in ground effect. (Said ground effect occurs above water, too...)
THe other question about CG is if it is variable gravitic decoupling; ie, can you get less than 98% nullification, or is it all or nothing. in an all or nothing situation, it can result in some seriously sudden transitions. EG, S2A rolling with CG off down taxiway, flips CG on and LURCHES upwards.
Higher density is lower stall speed. Higher density is usually obtained by lower altitude and/or higher humidity. Provided that the temperatures don't result in icing or fog, higher humidity provides denser atmosphere (for a given pressure) and thus more lift.
The Type S, under CT and MT, clearly has to vector the thrust, or come in tail-down. Under TNE & T4, it has to do the same, just with less thrust. Under TNE, even with the CG "Floating" at 98%, that's still going to accelerate you into a massive crunch, just not a total devastation crunch... (0.2m/s^2 still adds up to terminal velocity fast enough)
The S2 Serpent, however, can make a thrust-available or thrust off landing. (Spaceship One established heat shielding is not an absolute requirement....) It's roughly the size of a 727... and will have similar landing roll needs. But, if you have the fuel (not a given under TNE...) you can make a hybrid landing: feather in, rotate, aerodyne approach, flare to stall, touch on engines vectored thrust, lower the nose.
Takeoff: similar issues for the standard wedgie. The lifting airframe, however, can (in atmosphere) gain considerable lift bonus AND can trade forward vector for upward with pretty good efficiency. Most aircraft generate all their lift off the wings, therefore 1G lift at Std Temp, Press, Density and Gravity (henceforth STPDG) in straight and level flight at cruising speed.
Now, Airframes in STPDG situations can be safely assumed capable of 1.1G's of lift at full speed, or more. (Many don't even have a full G of thrust... if thrust is 1G+, they take forever to auto-break-over from the hammerhead stall...) At that rate, the lift generated post-flight is 0.1G, or 1m/s/s, leaving all engine thrust (2G's) for aiding. I can't do the needed math, but I know that you can optimize for somewhere around 2.1 positive g's lift this way, and maybe more. And, when high enough, you begin a rotation to transfer speed to upward climb. Not so important for the Type S2, in that only a few canonical worlds even approach 2G's.
Now, add CG into this. Now, downward force is 0.2m/s/s, so an airframe can/will throw that 1.08G (10.8m/s/s) left into upward climb... again STPDG. So it should be able to climb out at somewhere between 2.2 and 2.8G , vs 1.98G for the non-lifting Type S Wedgie.
Now, one important crunch under TNE: gravitic thrust is non-extant. (Doesn't exist at all in the TNE-OTU). Which means even more problems for both types... For lifting-airframes, it means problems only for takeoff, really. (In many cases, a direct takeoff may be more fuel efficient. Only when Local gravity is very close to the acceleration does the added lift become essential. With CG, the wings need to generate 2% optimal lift to get off the ground; think a 727 with a 200m takeoff roll... and that's the S2A design I posted to the TML many years ago.
Another consideration: a 0.9G thrust aircraft, with high lift wings, can generate up to 4 or 5 G's of effective in-atmosphere maneuver by aerodynamics. (Pipers can cancel themselves... with HL kits, they can be induced to make turns with G-loads in excess of the frame's strength.)
Airframes are a good thing. they add flexibility, in droves. Only TNE's rules provide a clear and present need for them... no-thrust landings.
(they also add potential plot complications. ForEx: the party buys a Type R off-contract for a song; she's in beautiful shape, good engines, etc... offered as is, and in an orbital yard. Problem is her landing gear and aerodyne control surfaces are frozen in a right banking climb... (and for TNE or T4, go ahead an knock out the CG, just to make it clear she's NOT a dirt-lover).
As for glide ratios: I've flow aircraft ranging from 1.8:1 (Beaver on floats with loads of drag from leftover WWII hardware, including a bomb-rack) through 23:1 (Schweitzer sailplane). The fundamental rule of landing is that you stall out when close enough to the ground not to damage the airframe. On the schewitzer, we hit ground effect after flare at abut 20m, at stall +5kts. Throwing the airbrakes on, we finally dropped out of the air (and ground effect) at stall-5kts, 250m down the runway, and rolled to a stop another 50m or so. Those last 3m vertical were not compromised at all until the aircraft finally lost ground effect and FELL 3m. Ground effect does wonderful, weird, and dangerous things.
In fact, ground effect is so profound, that an entire category of powered flight is devoted to it exclusively. THe soviets used a heavy lift airframe, designed for maximumization of ground effect, as a form of low-drag boat. (were it not for trees, it could work overland, as well.) Now, some use companies are making sporting craft in this range. They fly, but their lift is only 1G+ while in ground effect. (Said ground effect occurs above water, too...)
THe other question about CG is if it is variable gravitic decoupling; ie, can you get less than 98% nullification, or is it all or nothing. in an all or nothing situation, it can result in some seriously sudden transitions. EG, S2A rolling with CG off down taxiway, flips CG on and LURCHES upwards.
BetterThanLife
SOC-14 1K
I am going to handle this in two parts. First dealing with real aerodynamics and variable atmospheres. And Density-Altitude. Second part is landing and takeoff.
(In two responses.)
Lifting surfaces, such as wings or lifting bodies, are actually designed for maximum efficiency by being very good in a fairly limited range of performance area. For example most commercial aircraft don't travel above 40,000 feet or much below sealevel. and travel at speeds under 700 knots. Military aircraft have a wider range of capability but generally trade off with higher stall speeds, less fuel efficiency, and less stability. In fact some modern military aircraft are designed intentionally unstable. But even then most military aircraft operate in a fairly narrow range of atmospheric pressure. 0-80,000 feet. (The SR-71 and TR-1 being exceptions to the limit on altitude, but both of them are special craft and are pretty much limited to higher altitudes. To accomplish that range of different atmospheric pressures they use things like variable sweep wings, slotted flaps, variable leading edge slots, etc. But these things can only be taken so far before they create more of a liability than an asset and certainly would become more expensive the wider operating range you were dealing with.
Now when dealing with a starship that relies on aerodynamic lift to land and take off you have some interesting problems. First and foremost you would need a runway at the starport. (And of course you would need wheels not legs.) Second you have a much wider range of environments in which to generatte lift. Anywhere from a vaccuum to 3 atmospheres. Atmospheres that have different properties so lift may be more or less effective. No lift shape would be sufficeint to cover all the operating environments for a starship. For example landing on Pixie or Cymberline, which has an atmosphere only below certain altitudes and the higher points on the planet are actually in vaccuum. Cymberline specifically has atmosphere virtually restricted to valleys and canyons.
The concept works fine when you stay relatively close to a standard atmosphere but the farther you get from the atmosphere that the craft was actually designed for the less likely it is to actually work.
Absolutely. So far we are in 100% agreement. Now here comes the problem with airfoils on starships.
Lifting surfaces, such as wings or lifting bodies, are actually designed for maximum efficiency by being very good in a fairly limited range of performance area. For example most commercial aircraft don't travel above 40,000 feet or much below sealevel. and travel at speeds under 700 knots. Military aircraft have a wider range of capability but generally trade off with higher stall speeds, less fuel efficiency, and less stability. In fact some modern military aircraft are designed intentionally unstable. But even then most military aircraft operate in a fairly narrow range of atmospheric pressure. 0-80,000 feet. (The SR-71 and TR-1 being exceptions to the limit on altitude, but both of them are special craft and are pretty much limited to higher altitudes. To accomplish that range of different atmospheric pressures they use things like variable sweep wings, slotted flaps, variable leading edge slots, etc. But these things can only be taken so far before they create more of a liability than an asset and certainly would become more expensive the wider operating range you were dealing with.
Now when dealing with a starship that relies on aerodynamic lift to land and take off you have some interesting problems. First and foremost you would need a runway at the starport. (And of course you would need wheels not legs.) Second you have a much wider range of environments in which to generatte lift. Anywhere from a vaccuum to 3 atmospheres. Atmospheres that have different properties so lift may be more or less effective. No lift shape would be sufficeint to cover all the operating environments for a starship. For example landing on Pixie or Cymberline, which has an atmosphere only below certain altitudes and the higher points on the planet are actually in vaccuum. Cymberline specifically has atmosphere virtually restricted to valleys and canyons.
The concept works fine when you stay relatively close to a standard atmosphere but the farther you get from the atmosphere that the craft was actually designed for the less likely it is to actually work.
BetterThanLife
SOC-14 1K
Now for the other part.
BTW your earlier comment that some of the thrust is down therefore limiting the speed forward in an atmosphere doesn't quite work for me. Primarily because it is always the same amount of max speed regardless of the gravitational force of the planet. (Matter of fact it is also regardless of the atmospheric density or composition, which makes no sense at all.)
Next point. At higher densities your stall speed goes down and the speed of sound goes up. Here is the problem you run into with aerodynamic lift. As the aircraft approaches the speed of sound the air travelling over the lifting surface, is travelling faster than the aircraft and faster than the air travelling under the lifting surface. (It is the principal of lift.) Once the speed of the air above the lifting surface approaches the speed of sound a shockwave is formed which disrupts the lift of the vessel. Supersonic aircraft avoid this problem by getting through the transonic range as rapidily as possible and restoring lift once the shockwave is moved away from the top of the lifting surface. At sea level the speed of sound is approximately 700 knots. At 35,000 feet it is approximately 650 knots. This is a fairly narrow band that an aircraft would have to deal with. (less than 10% of your airspeed.) Whne dealing with different composition and densities of atmospheres you have a much wider range to deal with when it comes to the speed of sound. (A very complex series of math to even begin to try to calculate a lifting surface that would work on Earth, Venus and Jupiter. FOrget about all the possibilities out there when you leave the solar system.
The problem you run into using lifting surfaces, and designing lifting surfaces is all that control connections, all those control surfaces, and variable pieces that would need to be part of the craft take up lots of space and are only useful under very specific circumstances. It would be much more effecient to use CG for lift instead of a wing because you can always use CG to land, and takeoff, whether there is an atmosphere or not.It works when you are in an atmosphere and when you are in a vaccuum. (Provided you are well within the gravity well.)
However the Type-S clearly doesn't land tail down. Has nothing pictured in any of the plans or external view that implies that it can vector thrust to any significant degree. And is the ship that is shown turning over at the halfway point in the diagrams for sublight trips.
SO you need aerodynamic lift to get off the ground and land safely? Then how does a Serpent land on a Vaccuum world? (Or better yet take off from one?) OR worse yet how does a Fat Trader with only 1G of thrust, without CG, take off from a 1.1G vaccuum planet? (It doesn't.)
BTW your earlier comment that some of the thrust is down therefore limiting the speed forward in an atmosphere doesn't quite work for me. Primarily because it is always the same amount of max speed regardless of the gravitational force of the planet. (Matter of fact it is also regardless of the atmospheric density or composition, which makes no sense at all.)
Next point. At higher densities your stall speed goes down and the speed of sound goes up. Here is the problem you run into with aerodynamic lift. As the aircraft approaches the speed of sound the air travelling over the lifting surface, is travelling faster than the aircraft and faster than the air travelling under the lifting surface. (It is the principal of lift.) Once the speed of the air above the lifting surface approaches the speed of sound a shockwave is formed which disrupts the lift of the vessel. Supersonic aircraft avoid this problem by getting through the transonic range as rapidily as possible and restoring lift once the shockwave is moved away from the top of the lifting surface. At sea level the speed of sound is approximately 700 knots. At 35,000 feet it is approximately 650 knots. This is a fairly narrow band that an aircraft would have to deal with. (less than 10% of your airspeed.) Whne dealing with different composition and densities of atmospheres you have a much wider range to deal with when it comes to the speed of sound. (A very complex series of math to even begin to try to calculate a lifting surface that would work on Earth, Venus and Jupiter. FOrget about all the possibilities out there when you leave the solar system.
The problem you run into using lifting surfaces, and designing lifting surfaces is all that control connections, all those control surfaces, and variable pieces that would need to be part of the craft take up lots of space and are only useful under very specific circumstances. It would be much more effecient to use CG for lift instead of a wing because you can always use CG to land, and takeoff, whether there is an atmosphere or not.It works when you are in an atmosphere and when you are in a vaccuum. (Provided you are well within the gravity well.)
BetterThanLife
SOC-14 1K
One other quick point. Not all current Airframes have wings or are lifting bodies. The CH/MH-53 for example is definitely an airframe but not a lifting body. The thrust generated by the propeller generates 100% of the lift. And 100% of the forward velocity. It is the fastest and largest helicopter in US military inventory. The recently cancelled RAH-66 is also not a lifting body nor does it have wings. It was designed as a Stealth aircraft. And is also a helicopter. The term Airframe applies to craft designed to operate above the ground and does not require the craft to have either wings or be a lifting body.
One of the most agile and maneuverable craft in the world is the British Lynx, another is the newest version of the Hughes 500 series the NOTAR version of the 500 series. Yet these are both Helicopters. The airframes are designed to be light and strong but they have no wings and the bodies of these craft are designed, as much as possible, to be lift neutral. (In fact if you can get your hands on the cross section of the wings of the AH-1 and AH-64 I would think you would find that the wings of those airframes are also lift neutral.
One of the most agile and maneuverable craft in the world is the British Lynx, another is the newest version of the Hughes 500 series the NOTAR version of the 500 series. Yet these are both Helicopters. The airframes are designed to be light and strong but they have no wings and the bodies of these craft are designed, as much as possible, to be lift neutral. (In fact if you can get your hands on the cross section of the wings of the AH-1 and AH-64 I would think you would find that the wings of those airframes are also lift neutral.
No, the apache and cobra wings are not lift neutral... they also are not significant for lift, either.
Lifting Airframes are exceedingly useful in atmosphere, which, in any realistic (Or TNE/Late Hard Times campaign) are where the vast majority of the populations are.
The additional cost and maintenance do add up; CG is not a replacement for it (Cost is about the same in TNE... but usually both are better).
TNE creates a fuel-limited setting. Lifting Airframes (which, until final draft, was what Airframes were described as in T20, BTW) provide a safe and fuel efficient way to land a spacecraft (as you yourself said, 98+% safety rate... and both failures were the result of take-off damage). CG can make a 1:1 into a 50:1 glide slope. WIthout lifting airframes, the CG simply lowers impact speed and terminal velocity.
Lifting Airframes are exceedingly useful in atmosphere, which, in any realistic (Or TNE/Late Hard Times campaign) are where the vast majority of the populations are.
The additional cost and maintenance do add up; CG is not a replacement for it (Cost is about the same in TNE... but usually both are better).
TNE creates a fuel-limited setting. Lifting Airframes (which, until final draft, was what Airframes were described as in T20, BTW) provide a safe and fuel efficient way to land a spacecraft (as you yourself said, 98+% safety rate... and both failures were the result of take-off damage). CG can make a 1:1 into a 50:1 glide slope. WIthout lifting airframes, the CG simply lowers impact speed and terminal velocity.
BetterThanLife
SOC-14 1K
I am not disputing that a lifting body or lifting surfaces might be nice to have. I am questioning their usefulness vs. cost when other means of lift are possible that aren't dependent on atmospheric pressure, composition or other atmospheric conditions which can radically change the lifting properties of your airfoil.
So how does the standard air/raft and G-Carrier fly? They use Contragravity for lift. Their max and cruising speeds are not affected by atmospheric density, or lack thereof, nor is their max or cruising speeds affected by local gravity. It does take them longer to reach orbit on larger planets, however that is a straight porportional ratio, which has no relevence to gravity of the planet but the size of the world. And since both can reach orbit that tends to rule out ground effects playing a major role.
I know it is all a bunch of wand waving and silly incantations, until and unless artificial gravity is figured out.
BTW the 98.6+% safety rating does include all NASA manned spaceflight. (Including Mercury, Gemeni and Apollo flights.) However did not include destruction of the Apollo 3, and death of the crew during ground tests. (Though if you go to the NASA site they are currently calling that Apollo 1.)
Cost effectiveness? well, you lose 6.66 to 10% of cargo tonnage, and add 10% to the cost of the hull, under T20. But, you also gain the ability to make a no-engine landing in atmospheres. There is no CG (effectively) in T20; our thrust is supposed to overcome local. (1G won't on most size 8-A worlds). Additionally, you have increased maneuverability in atmosphere for high-G rated designs (like the Type T).
Under FF&S, you lose less (it's mass based there, so you'll have to rough guess at 15Mg/Td, and if over, iterate), but it's not bad. It gains the ability to burn almost no maneuver fuel for landing. A very important thing. (I've smacked planets with PC starships before... by simply achieving a fuel hit after commit burn.) Also, with CG, you need only about 0.1G thust anyway for takeoff, so takeoff matters not there.
The real question is, ARE YOU IN A TNE-ASSUMPTIONS UNIVERSE? If not, lifting airframes are a redundancy. (Under FF&S, lifting airframe is itself a redundnat phrase. ALL airframes are either rotary wing, fixed wing, or ornithopter designs.)
If not TNE, then the assumptions of MT may be valuable; MT assumed gravitic thrusters in sizes and rates of fuel use comparable to CT.
T20 is essentially CT-paradigm, not TNE-paradigm. HUGE differences. No magic-gravitic-diconnect. Instead, unexplained thrust systems which have no reaction mass on-mount. Without explicit CG separate from the drives, the redundancy factor is a valuable option for frontier craft.
None of the systems make adequate provisions for the effects of redundancy on moral; that's left to GM's.
CG is NOT available in CT/MT; gravitic modules there are thrust agencies, not the disconnect that TNE provides.
Gravitic thrust is not available in TNE. It is available in T4. Otherwise, the two tech paradigms are the same.
T20 is a CT/MT paradigm, for the most part, leaning more towards CT. Now, CT says that a 1G craft can lift off a size A world. It doesn't say how. MT explains this and other glitches by allowing overthrust AND thrust vectoring.
FF&S/TNE/T4 solved it by a very different mechanism: CG. Which has other nasty bits about it (Like not being a thrust agency at all, but a gravitic effect reduction. (Page 75, FF&S1)
Because of the three incompatible tech paradigms, one can not make a blanket tech statement. Likewise, one can not make a blanket setting-derived statement, at least not more detailed than Spacecraft must be able to withstand vacuum and move about the universe. (2300 doesn't even require thrust to do that!)
Airframes provide a redundancy in non-TNE universes, and possibly the only way a merchantman will take off froma size 8+ world. (BTW, the fuel ration to get to suborbital pop-ups can be estimated by simple looks at the sounding rockets (80-90% fuel) used for pop-up exo-atmosphere (>60mi), and comparing to the fuel used for WhiteKnight/Spaceship One (<50%). Same operational paradigm. Both make 60-some-odd mile pop-ups. Only one is resuseable. It also uses less fuel volume by vehicle. Yes, it takes longer to go up. Yes, it requires more complex parts.
Finesse is cheaper in the long run, always. Brute force can often get a job done in the short run. Controlled brute force can work miracles (Can we say Nuke Power?). In spaceflight, that's VERY true.
Lets look at the costs of a 400 TOnner in T20: she's going to lose 20 Td, at a cost maximum of KCr132 per ton of ship (vs SL, at max cost of KCr120 per ton; both needles). This adds KCr12 per ton, and costs 20 tons, or roughly 10% of cargo space, for 10KCr less per run, but a 20 tons that are seldom full. It does, however, pay off in full the first time the ship takes off from a high-G world, or lands safely without downed Maneuver drive.
She's only about 20% likely to fill 220 tons of cargo. So she's really losing 5-10 tons of used space... But we'l figure on full. She'll make no more than 25 jumps per year, so at cargo rates, that's KCr20x25 = KCr400 per year lost. x40 years, MCr16 lost revenue. If the ship only once during those 40 years has to use those wings, she's just saved 50+MCr.
BTW, if the T20 airframe isn't wings, it's NOT worth it. It was wings, and I'll PM hunter to clarify that for second printing... it's that much an issue. Under FF&S, airframes always include lifting structures.
Under FF&S, you lose less (it's mass based there, so you'll have to rough guess at 15Mg/Td, and if over, iterate), but it's not bad. It gains the ability to burn almost no maneuver fuel for landing. A very important thing. (I've smacked planets with PC starships before... by simply achieving a fuel hit after commit burn.) Also, with CG, you need only about 0.1G thust anyway for takeoff, so takeoff matters not there.
The real question is, ARE YOU IN A TNE-ASSUMPTIONS UNIVERSE? If not, lifting airframes are a redundancy. (Under FF&S, lifting airframe is itself a redundnat phrase. ALL airframes are either rotary wing, fixed wing, or ornithopter designs.)
If not TNE, then the assumptions of MT may be valuable; MT assumed gravitic thrusters in sizes and rates of fuel use comparable to CT.
T20 is essentially CT-paradigm, not TNE-paradigm. HUGE differences. No magic-gravitic-diconnect. Instead, unexplained thrust systems which have no reaction mass on-mount. Without explicit CG separate from the drives, the redundancy factor is a valuable option for frontier craft.
None of the systems make adequate provisions for the effects of redundancy on moral; that's left to GM's.
CG is NOT available in CT/MT; gravitic modules there are thrust agencies, not the disconnect that TNE provides.
Gravitic thrust is not available in TNE. It is available in T4. Otherwise, the two tech paradigms are the same.
T20 is a CT/MT paradigm, for the most part, leaning more towards CT. Now, CT says that a 1G craft can lift off a size A world. It doesn't say how. MT explains this and other glitches by allowing overthrust AND thrust vectoring.
FF&S/TNE/T4 solved it by a very different mechanism: CG. Which has other nasty bits about it (Like not being a thrust agency at all, but a gravitic effect reduction. (Page 75, FF&S1)
Because of the three incompatible tech paradigms, one can not make a blanket tech statement. Likewise, one can not make a blanket setting-derived statement, at least not more detailed than Spacecraft must be able to withstand vacuum and move about the universe. (2300 doesn't even require thrust to do that!)
Airframes provide a redundancy in non-TNE universes, and possibly the only way a merchantman will take off froma size 8+ world. (BTW, the fuel ration to get to suborbital pop-ups can be estimated by simple looks at the sounding rockets (80-90% fuel) used for pop-up exo-atmosphere (>60mi), and comparing to the fuel used for WhiteKnight/Spaceship One (<50%). Same operational paradigm. Both make 60-some-odd mile pop-ups. Only one is resuseable. It also uses less fuel volume by vehicle. Yes, it takes longer to go up. Yes, it requires more complex parts.
Finesse is cheaper in the long run, always. Brute force can often get a job done in the short run. Controlled brute force can work miracles (Can we say Nuke Power?). In spaceflight, that's VERY true.
Lets look at the costs of a 400 TOnner in T20: she's going to lose 20 Td, at a cost maximum of KCr132 per ton of ship (vs SL, at max cost of KCr120 per ton; both needles). This adds KCr12 per ton, and costs 20 tons, or roughly 10% of cargo space, for 10KCr less per run, but a 20 tons that are seldom full. It does, however, pay off in full the first time the ship takes off from a high-G world, or lands safely without downed Maneuver drive.
She's only about 20% likely to fill 220 tons of cargo. So she's really losing 5-10 tons of used space... But we'l figure on full. She'll make no more than 25 jumps per year, so at cargo rates, that's KCr20x25 = KCr400 per year lost. x40 years, MCr16 lost revenue. If the ship only once during those 40 years has to use those wings, she's just saved 50+MCr.
BTW, if the T20 airframe isn't wings, it's NOT worth it. It was wings, and I'll PM hunter to clarify that for second printing... it's that much an issue. Under FF&S, airframes always include lifting structures.
BetterThanLife
SOC-14 1K
There is CG in T20 but it isn't in the Starship design sequence. (Of course it wasn't in the starship design sequence from LBB5 either.) However it is explicit in the vehicle design sequence. (Grav Vehicles such as the air/raft would require CG to function.) And in the vehicle design sequence the amount of thrust to negate gravity is negligible and not part of the thrust calculations for the speed of the vehicle. The downward component also appears to take no appreciable mass. Extrapolating to Starships it makes sense. Now reading what DN had to say about HEPLAR then TNE drives and FF&S design stuff would be quite different. But for CT, MT and T20 while CG lift isn't explicit it may definitely be implied.
<Snipped a whole bunch of interesting information, and pretty much what I had already learned reading DN's stuff and Armais's stuff here.>
Now I didn't say airframes weren't worth it. I said, with the ability of Contra Gravity to generate lift then lifting surfaces were not worth it. Airframes implies a craft specifically designed to operate within an atmosphere minimizing the Coefficient of Drag. Generated lift may be one of several methods. Contragravity lift, such as the air/raft, Aerodynamic Lift, using wings or lifting bodies, or Thrust based lift, such as Helicopters and Harriers. Contragravity lift being the one that would be most effecient because it could be used in a wider range of circumstances and locations.
As for bugging Hunter about it? I would much prefer the attention in starship design for a second edition being to fix the problems with things like the standard designs having the wrong volumes for carried vehicles and the number of seats standard in a small craft. And the biggest starship problem in T20 is the big ship starship combat.
None of us really tested big ship combat during the T20 playtest. Dr. Skull said he'd played one or two, and they were working at that point, but that was well before a number of other changes.
Also, a very late change to Prior Experience rates massively upped skill totals.
And, no, there is NOT CG in the design sequences, in the FF&S sense. There is gravitic thrust. (Again, this is important, because the nature of the two in operation is very different.)
And starship design is unlikely to get changed. Combat, maybe a little. Hunter was fixated on the HG derivative.... Airframes and simplified computer rules are about the only real changes we got him to make for the design process (and to be honest, all that we felt were needed in the DESIGN sequences).
Your problem, really, is not the design sequence, as the combat system grafted on. Realize that a lot of late-on changes happened.
Also, a very late change to Prior Experience rates massively upped skill totals.
And, no, there is NOT CG in the design sequences, in the FF&S sense. There is gravitic thrust. (Again, this is important, because the nature of the two in operation is very different.)
And starship design is unlikely to get changed. Combat, maybe a little. Hunter was fixated on the HG derivative.... Airframes and simplified computer rules are about the only real changes we got him to make for the design process (and to be honest, all that we felt were needed in the DESIGN sequences).
Your problem, really, is not the design sequence, as the combat system grafted on. Realize that a lot of late-on changes happened.
BetterThanLife
SOC-14 1K
Actually my problem isn't the design sequence at all. I like it as is. My problem with the design sequence is the application, apparently incorrectly, of the design sequence that produces the "Standard Designs." here it is apparent that in the original thinking 1000Vls, not 1400vls is one DTon. And the designer of the small craft forgot to notice that all small craft require a small craft bridge which includes 2 seats. That is my only nit pick with the design sequence. Well that and the fact that you strip an old computer and an old powerplant out of a Type-S before turning it over to a detached duty Scout and replace them with brand new replacements. Since sensors are now tied to computer level and a Type-S Scout has insufficient sensors to see a planet right in front of it. Minimum sensor level that makes sense for a Scout Ship is 4. To have Level 4 sensors and arm the ship with a laser would require more power than the powerplant produces. Hence it was obviously replaced along with the sensors.
I never said CG was included in the sequence, I said it was implied. An Air/Raft clearly has no lift except that created by counter gravity principals, and forward thrust is independent of size or standard gravity of the planet you are travelling about in the air/raft over. So the part that keeps the air/raft in the air, or whatever the atmosphere is or isn't, is independent of the thrust that propells the vehicle forward. (That is the implication, nothing is stated hard and fast about it.)
Starship Combat, actually, would benefit from a major rewrite.
Again, Bhoins, FF&S is the terminology standard. It ain't "CG" principles, it is "gravitic thruster"; I nitpick on this one, as it's one that got missed in the playtest. (Vehicle design was much later in the sequneces. Many of us were showing burnout...)
gravitic thrust, as expressed in TNE and T4, is very different from contra-gravity. One generates thrust by means of gravitic theory; the other disconnects one from local gravity.
different paradigms entirely.
Yes, it's a nitpick. No, they are not mutually exclusive, but they are clearly NOT the same. CG CAN'T produce thrust other than by buoyancy, which will always be purely up/down.
But yes, I agree that the idea of CG is not explicitly DENIED in T20, nor is it implicitly included as a standard.
GRavitic thrust, however, is implicitly there. A different but possibly related technology.
It's kind of like comparing a GEV (compares to Graitic Thrust) to a helium Balloon (compares to CG). The GEV can, by skirt lifting, use the lift system to generate directional thrust (inefficiently, true, but for this simile, sufficient), while a balloon can not generate forward thrust at all, but can, by ballast or compression, moderate its lift. Both lift; only one can transition the lift energy into actual momentum. Both can be swept along by extant currents.
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
And yes, I agree, a major rewrite might be a good thing. But I also think it way to soon for a second edition. Start on it in a year, publish in two...
I think the biggest change, and the one most problematic, was the increase of the XP rates in CG. It massively changed the expected levels of characters, and nearly doubled the "Expected" levels of adds, because it shifted joe normal spaceman from level 2 to level 3-4. (To understand how this worked: take all the XP values on the worksheet, and halve them... so it was 500 XP per year, or 10XP per week of work... the rates for adventures, etc did NOT get doubled, probably an oversight).
Let us take a quick look at the draft rates for XP in CG when SS combat was tested. Labels:
T# Terms completed
S= XP for Survival (Draft 2000 per term, release 4000 per term) For frational terms, use fractional rate for this purpose.
P= XP for promotion (Draft 500, release 1000)
XPB= XP bonus roll (Draft 1000, release 1d4x1000) For frational terms, use fractional rate for this purpose.
D= Decoration XP (draft: 0/250/500/1000, release 0/2000/4000/8000; failed/MCUF/MCG/SEH)
TXP= XP totaled.
L= level range by TXP
GSR= Gunnery Skill Ranks (assuming not a class skill at level 1.)
note: Commission (draft 500, release 1000) is not on these tables, as we're looking at crew values, so no officers are being counted.
Gunners by Draft at time of work on Space Combat
T0.25 (1Y): S=500, P=0-500 XPB=0-250 D=0 TXP=500-1250 L=1-2 GSR=0.5-1.5
T0.5 (2y): S=1000, P=0-500 XPB=0-500 D=0-1000 TXP=1000-3000 L=2-3 GSR=1.5-2.5
T1: S=2000 P=0-500 XPB=0-1000 D=0-1000 TXP=2000-4500 L=2-3 CSR=1.5-2.5
T2: S=4000 P=0-1000 XPB=0-2000 D=0-2000 TXP=4000-9000 L=3-4 GSR=2.5-3.5
T3: S=6000 P=0-1500 XPB=0-3000 D=0-3000 TXP=6K-13.5K L=4-5 GSR=3.5-4.5
T4: S=8K P=0-2 XPB=0-4K D0=0-4K TXP=8K-18K L=4-6 GSR=3.5-5.5
T5:S=10K P=0-2.5K XPB=0-5K D=0-5K TXP=10k-22.5K L=5-7 GSB=4.5-6.5
Under LATE draft and release:
T0.25 (1Y): S=1000, P=0-1000 XPB=0-1000 D=0 TXP=1-3K L=2-3 GSR=1.5-2.5
T0.5 (2y): S=2000, P=0-1000 XPB=0-1000 D=0-8000 TXP=2K-12K L=2-5 GSR=1.5-4.5
T1: S=4K P=0-1K XPB=0-4K D=0-8k TXP=4K-17K L=3-6 CSR=2.5-5.5
T2: S=8K P=0-2K XPB=0-8K D=0-16k TXP=8k-34K L=4=8 GSR=3.5-7.5
T3: S=12K P=0-3K XPB=0-12k D=0-24k TXP=12k-51K L=5-10 GSR=4.5-9.5
T4: S=8K P=0-2 XPB=0-4K D0=0-4K TXP=8K-18K L=4-6 GSR=3.5-5.5
T5:S=20K P=0-5K XPB=0-20K D=0-40K TXP=20k-85K L=6-13 GSB=5.5-12.5
Does that shed some light on the numerical issues with the combat system?
Another note: the max skill adds for level also hae to account for Skill Focus, Synergy and Atts:
At level 1: Max +6 (a=+4, SF=+2) above ranks
At level 2: max +8 (Synergy bonus possible)
At level 8, Max +9 (an 18 can have been raised to a 20
At level 16 Max+10 (an 18 original can have been raise to a 22)
Gunnery gets two less, as I don't recall any synergy bonuses.
gravitic thrust, as expressed in TNE and T4, is very different from contra-gravity. One generates thrust by means of gravitic theory; the other disconnects one from local gravity.
different paradigms entirely.
Yes, it's a nitpick. No, they are not mutually exclusive, but they are clearly NOT the same. CG CAN'T produce thrust other than by buoyancy, which will always be purely up/down.
But yes, I agree that the idea of CG is not explicitly DENIED in T20, nor is it implicitly included as a standard.
GRavitic thrust, however, is implicitly there. A different but possibly related technology.
It's kind of like comparing a GEV (compares to Graitic Thrust) to a helium Balloon (compares to CG). The GEV can, by skirt lifting, use the lift system to generate directional thrust (inefficiently, true, but for this simile, sufficient), while a balloon can not generate forward thrust at all, but can, by ballast or compression, moderate its lift. Both lift; only one can transition the lift energy into actual momentum. Both can be swept along by extant currents.
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
And yes, I agree, a major rewrite might be a good thing. But I also think it way to soon for a second edition. Start on it in a year, publish in two...
I think the biggest change, and the one most problematic, was the increase of the XP rates in CG. It massively changed the expected levels of characters, and nearly doubled the "Expected" levels of adds, because it shifted joe normal spaceman from level 2 to level 3-4. (To understand how this worked: take all the XP values on the worksheet, and halve them... so it was 500 XP per year, or 10XP per week of work... the rates for adventures, etc did NOT get doubled, probably an oversight).
Let us take a quick look at the draft rates for XP in CG when SS combat was tested. Labels:
T# Terms completed
S= XP for Survival (Draft 2000 per term, release 4000 per term) For frational terms, use fractional rate for this purpose.
P= XP for promotion (Draft 500, release 1000)
XPB= XP bonus roll (Draft 1000, release 1d4x1000) For frational terms, use fractional rate for this purpose.
D= Decoration XP (draft: 0/250/500/1000, release 0/2000/4000/8000; failed/MCUF/MCG/SEH)
TXP= XP totaled.
L= level range by TXP
GSR= Gunnery Skill Ranks (assuming not a class skill at level 1.)
note: Commission (draft 500, release 1000) is not on these tables, as we're looking at crew values, so no officers are being counted.
Gunners by Draft at time of work on Space Combat
T0.25 (1Y): S=500, P=0-500 XPB=0-250 D=0 TXP=500-1250 L=1-2 GSR=0.5-1.5
T0.5 (2y): S=1000, P=0-500 XPB=0-500 D=0-1000 TXP=1000-3000 L=2-3 GSR=1.5-2.5
T1: S=2000 P=0-500 XPB=0-1000 D=0-1000 TXP=2000-4500 L=2-3 CSR=1.5-2.5
T2: S=4000 P=0-1000 XPB=0-2000 D=0-2000 TXP=4000-9000 L=3-4 GSR=2.5-3.5
T3: S=6000 P=0-1500 XPB=0-3000 D=0-3000 TXP=6K-13.5K L=4-5 GSR=3.5-4.5
T4: S=8K P=0-2 XPB=0-4K D0=0-4K TXP=8K-18K L=4-6 GSR=3.5-5.5
T5:S=10K P=0-2.5K XPB=0-5K D=0-5K TXP=10k-22.5K L=5-7 GSB=4.5-6.5
Under LATE draft and release:
T0.25 (1Y): S=1000, P=0-1000 XPB=0-1000 D=0 TXP=1-3K L=2-3 GSR=1.5-2.5
T0.5 (2y): S=2000, P=0-1000 XPB=0-1000 D=0-8000 TXP=2K-12K L=2-5 GSR=1.5-4.5
T1: S=4K P=0-1K XPB=0-4K D=0-8k TXP=4K-17K L=3-6 CSR=2.5-5.5
T2: S=8K P=0-2K XPB=0-8K D=0-16k TXP=8k-34K L=4=8 GSR=3.5-7.5
T3: S=12K P=0-3K XPB=0-12k D=0-24k TXP=12k-51K L=5-10 GSR=4.5-9.5
T4: S=8K P=0-2 XPB=0-4K D0=0-4K TXP=8K-18K L=4-6 GSR=3.5-5.5
T5:S=20K P=0-5K XPB=0-20K D=0-40K TXP=20k-85K L=6-13 GSB=5.5-12.5
Does that shed some light on the numerical issues with the combat system?
Another note: the max skill adds for level also hae to account for Skill Focus, Synergy and Atts:
At level 1: Max +6 (a=+4, SF=+2) above ranks
At level 2: max +8 (Synergy bonus possible)
At level 8, Max +9 (an 18 can have been raised to a 20
At level 16 Max+10 (an 18 original can have been raise to a 22)
Gunnery gets two less, as I don't recall any synergy bonuses.
Streamlined vs Partially Streamlined, in game terms
All IMTU
Some hull types can never land on a planet greater than size 0 - the hull cannot take the loads - e.g. dispersed, planetoid hulls
If not the above classes of hull, any of 'non-streamlined, streamlined, airframe' can land on any planetary surface, using contra-grav, without regard to plan grav, or atmosphere. How long it takes to do so is the critical point.
An airframe, by definition, is fully streamlined, with control surfaces and ability to generate full thrust in the g-well, inside the atmosphere. The huge advantage of airframe is the ability to pull sharp maneuvers "in the soup", in dense atmospheres, (the sort of place where people might care to live), using the atmosphere to advantage.
A airframe fighter or special hull could literally do circles around a semistreamlined box (standard streamlined hull designed for commerce). Such a fighter hull, if say tech 6+ (e.g. Warthog), might nail a high tech "streamlined" hull - staying on it's 6.
The real difference of streamlining class should be the military advantage of maneuverability.
Using whatever contragrav paradign, where contragrav is discussed, the following should apply:
the boxy hull (non-streamlined) should be able to slowly gain orbit (floating on grav) taking a very long time, perhaps 4 hours, multiple turns, in any case. Same for landing. It's a big fat slow stationary target, though.
A streamlined vessel should be able to apply thrust and accomplish the same task in 1 hour or so, but is very ungainly in it's maneuver - agility 0 pig. Whether thrust is hot jets or reactionless, should be the same effect.
An airframe can do the same, but have full agility in the atmosphere, gaining an agility advantage in combat. A true airframe should be able to stand on it's tail and gain orbit in one ship's turn. With hot Pilot roll. Similar for landing.
Sojourner
All IMTU
Some hull types can never land on a planet greater than size 0 - the hull cannot take the loads - e.g. dispersed, planetoid hulls
If not the above classes of hull, any of 'non-streamlined, streamlined, airframe' can land on any planetary surface, using contra-grav, without regard to plan grav, or atmosphere. How long it takes to do so is the critical point.
An airframe, by definition, is fully streamlined, with control surfaces and ability to generate full thrust in the g-well, inside the atmosphere. The huge advantage of airframe is the ability to pull sharp maneuvers "in the soup", in dense atmospheres, (the sort of place where people might care to live), using the atmosphere to advantage.
A airframe fighter or special hull could literally do circles around a semistreamlined box (standard streamlined hull designed for commerce). Such a fighter hull, if say tech 6+ (e.g. Warthog), might nail a high tech "streamlined" hull - staying on it's 6.
The real difference of streamlining class should be the military advantage of maneuverability.
Using whatever contragrav paradign, where contragrav is discussed, the following should apply:
the boxy hull (non-streamlined) should be able to slowly gain orbit (floating on grav) taking a very long time, perhaps 4 hours, multiple turns, in any case. Same for landing. It's a big fat slow stationary target, though.
A streamlined vessel should be able to apply thrust and accomplish the same task in 1 hour or so, but is very ungainly in it's maneuver - agility 0 pig. Whether thrust is hot jets or reactionless, should be the same effect.
An airframe can do the same, but have full agility in the atmosphere, gaining an agility advantage in combat. A true airframe should be able to stand on it's tail and gain orbit in one ship's turn. With hot Pilot roll. Similar for landing.
Sojourner
