Surface to Orbit at 1G
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Supplement Four
SOC-14 5K
Supplement Four
SOC-14 5K
Fritz_Brown
Super Moderator
If you can achieve even 1.01G (with "overdrive"), you can "fly" out of the gravity well - angle off, rather than straight up, so the planet falls away from you.
Fritz_Brown
Super Moderator
If you can achieve even 1.01G (with "overdrive"), you can "fly" out of the gravity well - angle off, rather than straight up, so the planet falls away from you.
Plankowner
SOC-13
(Puts on Aerospace Engineering Hat, canted slightly to the left, because it looks cool)...
There are actually a couple of issues in the surface-to-orbit thing. You can use a lifting body. This will give you lift greater than your thrust at lower altitudes. TL8 airplanes have a lift/thrust ratio of up to 20. The TL7 Space Shuttle, has a lift/thrust ratio of about 1 (a flying brick). This ratio drops off as you increase altitude, but it will allow you to gain considerable speed. Remember, it is VELOCITY, not ACCELLERATION that gets you to orbit.
The streamlined shapes (CT anyway) would allow a ship with a 1G accelleration to take off from just about any world with an atmosphere. As BillDowns mentioned though, if the size 8 world had no atmosphere, a 1G ship would not be able to take off.
The second issue is that most ships are not going to travel straight up. If nothing else, Aerospace Traffic Control (part of the Starport Authority?) will not let you. So just calculating a straight up accelleration won't work. Also, if you did use that method, you would have to subtract the planet's gravity from your accelleration (and account for air friction somehow).
Thirdly (and finally) you cannot figure just a straight up accelleration because you want to be in ORBIT at that altitude. That requires that you put some lateral velocity into your vector so that you are travelling around the planet, not straight away from it. That will take extra velocity, hence more time. Getting into a particular orbit around the Earth is a huge consideration when launching orbital vehicles. The International Space Station is placed so that it is half way between US and Russian launch sites. Both groups have to spend extra fuel to alter their launch trajectories to match that orbital inclination.
Remember, it may only take you 1/2 hour to get from DFW to IAH, but you still have to taxi on the runways at each end (not to mention security). I always used 10minutes*Size Code/G's for calculating orbital insertion.
(removes Hat, exposing his grey hair and bald spot)
There are actually a couple of issues in the surface-to-orbit thing. You can use a lifting body. This will give you lift greater than your thrust at lower altitudes. TL8 airplanes have a lift/thrust ratio of up to 20. The TL7 Space Shuttle, has a lift/thrust ratio of about 1 (a flying brick). This ratio drops off as you increase altitude, but it will allow you to gain considerable speed. Remember, it is VELOCITY, not ACCELLERATION that gets you to orbit.
The streamlined shapes (CT anyway) would allow a ship with a 1G accelleration to take off from just about any world with an atmosphere. As BillDowns mentioned though, if the size 8 world had no atmosphere, a 1G ship would not be able to take off.
The second issue is that most ships are not going to travel straight up. If nothing else, Aerospace Traffic Control (part of the Starport Authority?) will not let you. So just calculating a straight up accelleration won't work. Also, if you did use that method, you would have to subtract the planet's gravity from your accelleration (and account for air friction somehow).
Thirdly (and finally) you cannot figure just a straight up accelleration because you want to be in ORBIT at that altitude. That requires that you put some lateral velocity into your vector so that you are travelling around the planet, not straight away from it. That will take extra velocity, hence more time. Getting into a particular orbit around the Earth is a huge consideration when launching orbital vehicles. The International Space Station is placed so that it is half way between US and Russian launch sites. Both groups have to spend extra fuel to alter their launch trajectories to match that orbital inclination.
Remember, it may only take you 1/2 hour to get from DFW to IAH, but you still have to taxi on the runways at each end (not to mention security). I always used 10minutes*Size Code/G's for calculating orbital insertion.
(removes Hat, exposing his grey hair and bald spot)
Plankowner
SOC-13
(Puts on Aerospace Engineering Hat, canted slightly to the left, because it looks cool)...
There are actually a couple of issues in the surface-to-orbit thing. You can use a lifting body. This will give you lift greater than your thrust at lower altitudes. TL8 airplanes have a lift/thrust ratio of up to 20. The TL7 Space Shuttle, has a lift/thrust ratio of about 1 (a flying brick). This ratio drops off as you increase altitude, but it will allow you to gain considerable speed. Remember, it is VELOCITY, not ACCELLERATION that gets you to orbit.
The streamlined shapes (CT anyway) would allow a ship with a 1G accelleration to take off from just about any world with an atmosphere. As BillDowns mentioned though, if the size 8 world had no atmosphere, a 1G ship would not be able to take off.
The second issue is that most ships are not going to travel straight up. If nothing else, Aerospace Traffic Control (part of the Starport Authority?) will not let you. So just calculating a straight up accelleration won't work. Also, if you did use that method, you would have to subtract the planet's gravity from your accelleration (and account for air friction somehow).
Thirdly (and finally) you cannot figure just a straight up accelleration because you want to be in ORBIT at that altitude. That requires that you put some lateral velocity into your vector so that you are travelling around the planet, not straight away from it. That will take extra velocity, hence more time. Getting into a particular orbit around the Earth is a huge consideration when launching orbital vehicles. The International Space Station is placed so that it is half way between US and Russian launch sites. Both groups have to spend extra fuel to alter their launch trajectories to match that orbital inclination.
Remember, it may only take you 1/2 hour to get from DFW to IAH, but you still have to taxi on the runways at each end (not to mention security). I always used 10minutes*Size Code/G's for calculating orbital insertion.
(removes Hat, exposing his grey hair and bald spot)
There are actually a couple of issues in the surface-to-orbit thing. You can use a lifting body. This will give you lift greater than your thrust at lower altitudes. TL8 airplanes have a lift/thrust ratio of up to 20. The TL7 Space Shuttle, has a lift/thrust ratio of about 1 (a flying brick). This ratio drops off as you increase altitude, but it will allow you to gain considerable speed. Remember, it is VELOCITY, not ACCELLERATION that gets you to orbit.
The streamlined shapes (CT anyway) would allow a ship with a 1G accelleration to take off from just about any world with an atmosphere. As BillDowns mentioned though, if the size 8 world had no atmosphere, a 1G ship would not be able to take off.
The second issue is that most ships are not going to travel straight up. If nothing else, Aerospace Traffic Control (part of the Starport Authority?) will not let you. So just calculating a straight up accelleration won't work. Also, if you did use that method, you would have to subtract the planet's gravity from your accelleration (and account for air friction somehow).
Thirdly (and finally) you cannot figure just a straight up accelleration because you want to be in ORBIT at that altitude. That requires that you put some lateral velocity into your vector so that you are travelling around the planet, not straight away from it. That will take extra velocity, hence more time. Getting into a particular orbit around the Earth is a huge consideration when launching orbital vehicles. The International Space Station is placed so that it is half way between US and Russian launch sites. Both groups have to spend extra fuel to alter their launch trajectories to match that orbital inclination.
Remember, it may only take you 1/2 hour to get from DFW to IAH, but you still have to taxi on the runways at each end (not to mention security). I always used 10minutes*Size Code/G's for calculating orbital insertion.
(removes Hat, exposing his grey hair and bald spot)
Fritz_Brown
Super Moderator
Ummm, well yeah. But, if your acceleration is 0, so is your speed over the long run. What with inertia and all that.
Fritz_Brown
Super Moderator
Ummm, well yeah. But, if your acceleration is 0, so is your speed over the long run. What with inertia and all that.
If one is willing to borrow concepts from TNE (ones which can be implied from the CT tables anyway): Perhaps the M-Drive includes some form of gravitic system which reduces the effects of gravity but provides no thrust. this would allow any craft with positive G's to take off.
If one is willing to borrow concepts from TNE (ones which can be implied from the CT tables anyway): Perhaps the M-Drive includes some form of gravitic system which reduces the effects of gravity but provides no thrust. this would allow any craft with positive G's to take off.
mike wightman
SOC-14 10K
Yep, that'll work. Have the maneuver drive include null-grav modules sufficient to neutralise its gravitational mass and then use your 1G of thrust to make orbit.
mike wightman
SOC-14 10K
Yep, that'll work. Have the maneuver drive include null-grav modules sufficient to neutralise its gravitational mass and then use your 1G of thrust to make orbit.
Plankowner
SOC-13
Ummm, well yeah. But, if your acceleration is 0, so is your speed over the long run. What with inertia and all that. </font>[/QUOTE]OK Fritz, maybe I was a bit overdramatic.
What I meant was that is might be possible to reach orbit with less than 1G accelleration. Again, I was only accounting for aerodynamic lift. Contra-Gravity plates would certainly solve the problem.
The TNE solution seems to be quite elegant. Would that also explain the Air Raft? It has a small engine to provide thrust while the Grav Plate nullify gravitic effects?
(Visions of horse-drawn Grav Sleds float through my vision...)
Plankowner
SOC-13
Ummm, well yeah. But, if your acceleration is 0, so is your speed over the long run. What with inertia and all that. </font>[/QUOTE]OK Fritz, maybe I was a bit overdramatic.
What I meant was that is might be possible to reach orbit with less than 1G accelleration. Again, I was only accounting for aerodynamic lift. Contra-Gravity plates would certainly solve the problem.
The TNE solution seems to be quite elegant. Would that also explain the Air Raft? It has a small engine to provide thrust while the Grav Plate nullify gravitic effects?
(Visions of horse-drawn Grav Sleds float through my vision...)
Supplement Four
SOC-14 5K
Wasn't that what I basically said before when I mentioned that a ship has four basic drive systems: Jump Drive; Manuever Drive; Attitude Thrusters; and Contra-Grav drive?
The Contra-Grav drive, used in gravity fields, allays some of the gravitational pull (like an Air/Raft), reducing the pull of the planet--allowing the 1G M-Drive to push the ship to escape velocity.
Supplement Four
SOC-14 5K
Wasn't that what I basically said before when I mentioned that a ship has four basic drive systems: Jump Drive; Manuever Drive; Attitude Thrusters; and Contra-Grav drive?
The Contra-Grav drive, used in gravity fields, allays some of the gravitational pull (like an Air/Raft), reducing the pull of the planet--allowing the 1G M-Drive to push the ship to escape velocity.
Plankowner
SOC-13
Probably, I guess in my case I didn't quite understand the distinction/functional differences.
WJP get credit for this idea first!
WJP get credit for this idea first!
Plankowner
SOC-13
Probably, I guess in my case I didn't quite understand the distinction/functional differences.
WJP get credit for this idea first!
WJP get credit for this idea first!
