Purely speculative, but has Orbital mentioned any possibility of a development path for Taurus-II to lead to heavier payload capacities? Perhaps outrigger SRMs or multi-core configurations?
The Taurus II User's manual publicly appeared on-line on or about December 28, 2009. It can be reviewed at http://www.orbital.com/NewsInfo/Publications/Taurus_II_UG.pdf .
I wonder how difficult this would be to fix and would it impact the payload too badly?
Looking the users guide it seems the Castor 30 is not an issue to making this a crew vehicle.It's max acceleration is only 3.7g with in the limits of acceptable which I believe is 4 - 4.5g.Instead the problem is in the first stage acceleration profile with a max acceleration of of 6g well outside NASA limits.
Quote from: Patchouli on 01/06/2010 04:03 pmLooking the users guide it seems the Castor 30 is not an issue to making this a crew vehicle.It's max acceleration is only 3.7g with in the limits of acceptable which I believe is 4 - 4.5g.Instead the problem is in the first stage acceleration profile with a max acceleration of of 6g well outside NASA limits.What NASA limits?
I figure any new crew transport vehicle must meet the requirements set by the Saturn LV and the Shuttle. These same rules also apply to amusement park rides so it's a perfectly reasonable and logical requirement.
That's some "interesting" velocity behavior at different milestones in the flight in "Figure 3.2-2. Taurus II Typical 3-Stage Mission Profile to LEO". Jumping up and down until payload separation at 2490 m/s? I should hope not!
I'm even a little concerned about the timeline itself. Could they really be planning a 59 second coast between stage 1 MECO and stage 2 ignition?
Quote from: sdsds on 01/06/2010 06:34 pmI'm even a little concerned about the timeline itself. Could they really be planning a 59 second coast between stage 1 MECO and stage 2 ignition? Note the table above the erroneous one has numbers that appear correct and it says 1st stage burns out at 4600 m/s. The coast costs them "only" 50 m/s.
Quote from: ugordan on 01/06/2010 06:39 pmQuote from: sdsds on 01/06/2010 06:34 pmI'm even a little concerned about the timeline itself. Could they really be planning a 59 second coast between stage 1 MECO and stage 2 ignition? Note the table above the erroneous one has numbers that appear correct and it says 1st stage burns out at 4600 m/s. The coast costs them "only" 50 m/s.It seems likely the interval between MECO and S2 ignition is only 3 or 4 seconds,
The Taurus II lifts off the pad approximately 2 seconds after Stage 1 ignition. Stage 1 burns for approximately 223 seconds, and separates after a brief post-burn coast. The upper stage stack continues to coast for approximately 50 seconds before the fairing is jettisoned. After fairing jettison, Stage 2 is ignited and boosts the upper stack to an altitude of approximately 153 km x 100 km before Stage 2 burnout and separation occurs, at 427 seconds into the flight.
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The Taurus II ACS provides three-axis attitude control throughout boosted flight and coast phases. The ACS uses the two main engine configuration to provide yaw, pitch and roll control during Stage 1 flight. Stage 2 flight is controlled by the combination of the Stage 2 TVC and the onboard ACS system located on the avionics ring. The Stage 2 ACS employs a cold gas nitrogen system with heritage from all of Orbital’s space launch vehicles.