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Mickey,
I am sorry not to have any trajectory information of the Ares 1.
With the prior configuration I tried to fly manually the same profile as you assume (that is target and hold 20° inclination until the trajectory rises again).
With the reduced power of the J-2X I try to get more horizontal speed out of the 1st stage by inclining down to 15°. During 2nd stage burn I don't want to drop too far, so I point up to ~42° to null the vertical speed, coming back to horizontal gradually. At the end of the burn I try to get a reasonable vertical speed so the burnt-out second stage climbs at first and then falls back into the Pacific. If this insertion orbit is too circular I tend to hit the American west coast or the Rocky Mountain area (something I would try to avoid )
Lateral adjustment is required for launches due east also. The trajectory of the rendezvous vessel will usually not pass directly overhead, so a little adjustment is necessary.
_______
Concerning the 10% 'Orbiter bonus' on the engine power and ISP:
dV is very precious in real world rocketry, so precise steering is required to reach the goal. When 'eyeballing' a launch with standard Orbiter instruments, only very experienced pilots will reach orbit. The remaining 90% may become frustrated because they can't even make it to orbit. To increase the playability Martin uses a little extra margin in his Atlantis shuttle:
< quote from Orbiter SDK >
const double ORBITER_MAIN_ISP0 = 5000.0;
const double ORBITER_MAIN_ISP1 = 4000.0;
// Vacuum and sea-level fuel-specific impulse for orbiter main engines [m/s]
// using H2/O2 (hydrogen/oxygen)
// The correct ISP0 is about 3532 m/s!
</ unquote >
I am not quite sure on the 3532 m/s (seems a little low, might be a typo from 4532), but the real ISP is definitely not 5000 m/s. Currently I am taking his approach as a reference. If we can ensure that most pilots can reach orbit by providing them a method or autopilot not requiring a 'bonus' then I will omit it, but please understand that playability for me is even more important than bare realism
PS: Antonio, thanks for your kind offer to use your meshes and data again.
Will gladly use them, saves me a lot of work on the launcher!
I am sorry not to have any trajectory information of the Ares 1.
With the prior configuration I tried to fly manually the same profile as you assume (that is target and hold 20° inclination until the trajectory rises again).
With the reduced power of the J-2X I try to get more horizontal speed out of the 1st stage by inclining down to 15°. During 2nd stage burn I don't want to drop too far, so I point up to ~42° to null the vertical speed, coming back to horizontal gradually. At the end of the burn I try to get a reasonable vertical speed so the burnt-out second stage climbs at first and then falls back into the Pacific. If this insertion orbit is too circular I tend to hit the American west coast or the Rocky Mountain area (something I would try to avoid )
Lateral adjustment is required for launches due east also. The trajectory of the rendezvous vessel will usually not pass directly overhead, so a little adjustment is necessary.
_______
Concerning the 10% 'Orbiter bonus' on the engine power and ISP:
dV is very precious in real world rocketry, so precise steering is required to reach the goal. When 'eyeballing' a launch with standard Orbiter instruments, only very experienced pilots will reach orbit. The remaining 90% may become frustrated because they can't even make it to orbit. To increase the playability Martin uses a little extra margin in his Atlantis shuttle:
< quote from Orbiter SDK >
const double ORBITER_MAIN_ISP0 = 5000.0;
const double ORBITER_MAIN_ISP1 = 4000.0;
// Vacuum and sea-level fuel-specific impulse for orbiter main engines [m/s]
// using H2/O2 (hydrogen/oxygen)
// The correct ISP0 is about 3532 m/s!
</ unquote >
I am not quite sure on the 3532 m/s (seems a little low, might be a typo from 4532), but the real ISP is definitely not 5000 m/s. Currently I am taking his approach as a reference. If we can ensure that most pilots can reach orbit by providing them a method or autopilot not requiring a 'bonus' then I will omit it, but please understand that playability for me is even more important than bare realism
PS: Antonio, thanks for your kind offer to use your meshes and data again.
Will gladly use them, saves me a lot of work on the launcher!