Trajectory Office backroom

Cras

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You don't have to use the D3D9 client.

You do once you have tried it. Once used to the better graphics and performance, it is very hard to go back to in-line client. At least for me. I still switch back to it once in a while when I must land at night, or want to EVA with Orulex.
 

Arrowstar

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Let's please keep this thread on topic. It is to discuss the trajectory work that is required for the Mars-bound missions. :)
 

Napalm42

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This is a bit of a nagging concern that's been bothering me a little for the past few days.

Should we have to perform an abort (unlikely, but hey, some dastardly pilot can turn the whole program on it's head with one missed MCC :lol:) the evac shuttle would only need enough oxygen to tough out the rest of the trip correct, since the elliptical nature of the orbit would allow it to return back to Earth, or am I just looking at the MFD display wrong. I have a nagging suspicion that the natural rotation of the planets would not allow a little-to-no burn return.
 

Arrowstar

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I can (and have) found trajectories that would require little-to-no deltaV to swing by Mars and get back to Earth. Mission management folks, should I investigate this further?

Good idea, Napalm. :)
 

dgatsoulis

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I've had some time today to check the first launch window. As a rule of thumb, i have found that it's always good to launch for Mars when it is ahead of Earth by ~45 degrees (relative to the Sun).

So i was surprized to see that the December 10th date was at an angle higher than that but after trying different combinations on TransX, i got a nice 3.75 km/s TMI plan (from a starting orbit of 200x200 km - 43 degrees incl. Date 12/12/2013). Encounter dv was about 3.35 km/s.

I pushed the date a bit forward (January 1st 2014), so that the angle was about 45 degrees and tried again. The eject dv was about the same (3.76 km/s), the inclination of the parking orbit was at ~38 degrees and the encounter dv was a little bit higher (3.6 km/s).

:thumbup: to our Trajectory Officer.
:cheers:
 

Arrowstar

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Great, thanks! I'm happy to see the TOT's trajectory solutions validated to some extent, it's quite pleasing. Nice work! :thumbup:

I'm going to put together some "free return" trajectories after Christmas for each of those launch windows. It'll be on management to decide which window (direct or free trajectory) is used for each mission.
 

dgatsoulis

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Great, thanks! I'm happy to see the TOT's trajectory solutions validated to some extent, it's quite pleasing. Nice work! :thumbup:

I'm pretty sure that if i'd spent a little more time with the plan, we'd arrive at the same dates and arrival dVs. The only thing i don't get is the depart window dV. (How it corresponds to the actual departure dV, when the spacecraft is already in orbit, aligned with the plan).

I'm going to put together some "free return" trajectories after Christmas for each of those launch windows. It'll be on management to decide which window (direct or free trajectory) is used for each mission.

I don't think that you'd have to do that for any flights, other than the one's with humans onboard. But as you said, "It'll be on management to decide."
 

Arrowstar

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Alright, a few runs of the TOT gave me a 2018 "free return" trajectory from Earth to Mars and back to Earth. I concentrated on this launch window as I do believe that this is the one we're sending people with. Here are the numbers:

Code:
TRAJECTORY OPTIMIZATION TOOL v2
Optimization Report - 25-Dec-2011 01:26:50
Flight Plan: Earth-Mars-Earth Free Return
----------------------------------------------------------------


RESULTS
--------------------------------
OPTIMUM EARTH DEPARTURE DATE: 12/25/2017 2:57:18 - C3: 40.3774 km²/sec²
OPTIMUM MARS SWINGBY DATE: 8/18/2018 11:26:1 - Powered Delta-V Required: 4.2443e-008 km/sec
OPTIMUM EARTH ARRIVAL DATE: 5/13/2019 14:41:41 - Body-centric Arrival Velocity: 8.5784 km/sec

TOTAL COST: 57.5342107


ORBITAL ELEMENTS - J2000 Reference Frame
--------------------------------
LEG 1 (Number of Full Revolutions: 0)
-Semi-major Axis: 171233880.8021140 km
-Eccentricity: 0.2368274
-Inclination: 23.4269808 deg
-Long. of Ascending Node: 6.6300672 deg
-Argument of Periapse: 152.5975570 deg
-True Anomaly (start): 294.5773990 deg
-True Anomaly (end): 159.1412543 deg

LEG 2 (Number of Full Revolutions: 0)
-Semi-major Axis: 160090781.4489947 km
-Eccentricity: 0.2969217
-Inclination: 24.6122267 deg
-Long. of Ascending Node: 3.5254453 deg
-Argument of Periapse: 132.4563578 deg
-True Anomaly (start): 182.1185011 deg
-True Anomaly (end): 96.6253796 deg

Here's a picture of about what the trajectory would look like:

emei.png

My thought is that we should use this flight plan, as it isn't too much worse than the trajectory I posted previously (okay, 5 times the C3, but I think the James Cook can handle it) and we get the added benefit of being able to save the crew if needed. Again, though, I'd like to get some feedback from the pilots and other folks on the project.
 
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Arrowstar

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Couldn't tell you. What I do see is that if we put the Cook into an equatorial orbit (radius 7000 km), it'll only take 3.5 km/s of dV to escape Earth orbit:

Code:
Computing Departure Burn...Done!                                                    
Burn Delta-V is 3.5602 km/s.                                                        
Burn should be performed at true anomaly of 173.3137 degrees of pre-departure orbit.
Burn Vector is as follows:                                                          
--J2000 X Component: -0.39291 km/s                                                  
--J2000 Y Component: -3.3516 km/s                                                   
--J2000 Z Component: 1.1345 km/s                                                    
--V Component: 3.3746 km/s                                                          
--N Component: 1.1345 km/s                                                          
--C Component: 5.5511e-017 km/s                                                     
Hyperbolic Departure Orbital Elements are:                                          
--Semi-major Axis: -59839.1693 km                                                   
--Eccentricity: 1.117                                                               
--Inclination: 5.9307 deg                                                           
--Right Asc of Asc Node: 173.3137 deg                                               
--Argument of Periapse: 0 deg                                                       
Constraint Error is 0.                                                              
##################################################################

If we place it into a 28.5 degree circular orbit (same 7000 km radius), we get the following:

Code:
Computing Departure Burn...Done!                                                    
Burn Delta-V is 6.3602 km/s.                                                        
Burn should be performed at true anomaly of 171.9502 degrees of pre-departure orbit.
Burn Vector is as follows:                                                          
--J2000 X Component: -0.21482 km/s                                                  
--J2000 Y Component: -4.2801 km/s                                                   
--J2000 Z Component: 4.6996 km/s                                                    
--V Component: 1.5341 km/s                                                          
--N Component: 6.1724 km/s                                                          
--C Component: 4.9405e-015 km/s                                                     
Hyperbolic Departure Orbital Elements are:                                          
--Semi-major Axis: -59839.1693 km                                                   
--Eccentricity: 1.117                                                               
--Inclination: 7.0681 deg                                                           
--Right Asc of Asc Node: 140.2245 deg                                               
--Argument of Periapse: 32.8896 deg                                                 
Constraint Error is 0.                                                              
##################################################################

It pays to keep the Cook in an equatorial orbit unless its so overpowered that it can stand to lose 3 km/s of dV. But I'd rather launch more rockets to the Cook from Earth for supply and whatnot, and provide the Cook with dV margin. But, as usual, its up to the managers. :)
 

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mikusingularity
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Couldn't tell you. What I do see is that if we put the Cook into an equatorial orbit (radius 7000 km), it'll only take 3.5 km/s of dV to escape Earth orbit:

Code:
Computing Departure Burn...Done!                                                    
Burn Delta-V is 3.5602 km/s.                                                        
Burn should be performed at true anomaly of 173.3137 degrees of pre-departure orbit.
Burn Vector is as follows:                                                          
--J2000 X Component: -0.39291 km/s                                                  
--J2000 Y Component: -3.3516 km/s                                                   
--J2000 Z Component: 1.1345 km/s                                                    
--V Component: 3.3746 km/s                                                          
--N Component: 1.1345 km/s                                                          
--C Component: 5.5511e-017 km/s                                                     
Hyperbolic Departure Orbital Elements are:                                          
--Semi-major Axis: -59839.1693 km                                                   
--Eccentricity: 1.117                                                               
--Inclination: 5.9307 deg                                                           
--Right Asc of Asc Node: 173.3137 deg                                               
--Argument of Periapse: 0 deg                                                       
Constraint Error is 0.                                                              
##################################################################
If we place it into a 28.5 degree circular orbit (same 7000 km radius), we get the following:

Code:
Computing Departure Burn...Done!                                                    
Burn Delta-V is 6.3602 km/s.                                                        
Burn should be performed at true anomaly of 171.9502 degrees of pre-departure orbit.
Burn Vector is as follows:                                                          
--J2000 X Component: -0.21482 km/s                                                  
--J2000 Y Component: -4.2801 km/s                                                   
--J2000 Z Component: 4.6996 km/s                                                    
--V Component: 1.5341 km/s                                                          
--N Component: 6.1724 km/s                                                          
--C Component: 4.9405e-015 km/s                                                     
Hyperbolic Departure Orbital Elements are:                                          
--Semi-major Axis: -59839.1693 km                                                   
--Eccentricity: 1.117                                                               
--Inclination: 7.0681 deg                                                           
--Right Asc of Asc Node: 140.2245 deg                                               
--Argument of Periapse: 32.8896 deg                                                 
Constraint Error is 0.                                                              
##################################################################
It pays to keep the Cook in an equatorial orbit unless its so overpowered that it can stand to lose 3 km/s of dV. But I'd rather launch more rockets to the Cook from Earth for supply and whatnot, and provide the Cook with dV margin. But, as usual, its up to the managers. :)

But doesn't that mostly depend on the longitude of the ascending node, not the inclination?
 

Arrowstar

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I've been setting RAAN to 0 degrees for these studies (as I was primarily interested in the effect of inclination, as that impacts launch site), but I can shift RAAN around too and see what happens. :) I'll do that after Christmas, as its late here now!
 

flytandem

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I have limited understanding of the numbers being crunched here, but I did hop into the cockpit with coffee in hand this morning while family were opening presents and started with the Dec 25 2017 suggested start date and visual understanding of an inward eject to Mars for a sling back to Earth 17 months later. I tweaked it to get the sling at Mars as close as comfortable and came up with an eject deltaV of 5579 m/s from a 200-200 km agl orbit that had a due east launch heading from the Cape. The sling at Mars is retrograde with Pe at about 248 km agl. I have a couple of scenarios below, the first is the scenario (TransX) from the ground up, ready for launch and the second is from the parking orbit with the eject maneuver ready to burn.

ready for launch...
Code:
BEGIN_DESC

END_DESC

BEGIN_ENVIRONMENT
  System Sol
  Date MJD 58112.4121870860
END_ENVIRONMENT

BEGIN_FOCUS
  Ship 3
END_FOCUS

BEGIN_CAMERA
  TARGET 3
  MODE Cockpit
  FOV 60.00
END_CAMERA

BEGIN_HUD
  TYPE Surface
END_HUD

BEGIN_MFD Left
  TYPE User
  MODE TransX
  Ship  3
  FNumber 5
  Int 1
  Orbit True
  Vector  -5294006.85645 2082335.91523 2868304.32608
  Vector  -131.500119642 153.923118837 -354.454080865
  Double  3.98600439969e+014
  Double  58112.412187
  Handle Earth
  Handle NULL
  Handle NULL
Select Target
 0 Escape
Autoplan
0 0
Plan type
0 0
Plan
0 1
Plan
0 0
Plan
0 0
Select Minor
 0 None
Manoeuvre mode
0 0
Base Orbit
0 0
Prograde vel.
 0  0
Man. date
 0  58112.412187
Outward vel.
 0  0
Ch. plane vel.
 0  0
Intercept with
0 0
Orbits to Icept
0 0
Graph projection
0 3
Scale to view
0 0
Advanced
0 0
Pe Distance
 0  6571244.85262
Ej Orientation
 2  0.435599274713
Equatorial view
0 0
Finvars
  Finish BaseFunction
  Int 2
  Orbit False
  Handle Sun
  Handle Earth
  Handle Mars
Select Target
 0 Mars
Autoplan
0 0
Plan type
0 2
Plan
0 0
Plan
0 0
Plan
0 1
Select Minor
 0 None
Manoeuvre mode
0 0
Base Orbit
0 1
Prograde vel.
 0  0
Man. date
 0  58112.4121631
Outward vel.
 0  0
Ch. plane vel.
 0  0
Intercept with
0 0
Orbits to Icept
0 0
Graph projection
0 0
Scale to view
0 0
Advanced
0 0
Prograde vel.
 0  1453.7004971
Eject date
 2  58112.4732801
Outward vel.
 3  -7110.94024409
Ch. plane vel.
 3  -2280.15635591
Finvars
  Finish BaseFunction
  Int 4
  Orbit True
  Vector  260091473.417 1089662522.58 6096197022.11
  Vector  -314.578298454 -1340.10620713 -7485.83425194
  Double  4.28282991638e+013
  Double  58307.8576671
  Handle Mars
  Handle NULL
  Handle NULL
Select Target
 0 Escape
Autoplan
0 0
Plan type
0 1
Plan
0 0
Plan
0 1
Plan
0 0
Select Minor
 0 None
Manoeuvre mode
0 0
Base Orbit
0 0
Prograde vel.
 0  0
Man. date
 0  58112.412187
Outward vel.
 0  0
Ch. plane vel.
 0  0
Intercept with
0 0
Orbits to Icept
0 0
Graph projection
0 0
Scale to view
0 0
Advanced
0 0
View Orbit
0 0
Finvars
  Finish BaseFunction
  Int 3
  Orbit True
  Vector  100036396735 -6337262217.16 -185011493377
  Vector  19566.7232022 -524.849486004 6478.52922727
  Double  1.32712482783e+020
  Double  58317.2762728
  Handle Sun
  Handle Mars
  Handle Earth
Select Target
 0 Earth
Autoplan
0 0
Plan type
0 2
Plan
0 0
Plan
0 0
Plan
0 2
Select Minor
 0 None
Manoeuvre mode
0 0
Base Orbit
0 0
Prograde vel.
 0  0
Man. date
 0  58112.412161
Outward vel.
 0  0
Ch. plane vel.
 0  0
Intercept with
0 0
Orbits to Icept
0 1
Graph projection
0 0
Scale to view
0 0
Advanced
0 0
Velocity.
 0  0
Outward angle
 2  2.47528144665
Inc. angle
 3  0.0217370286361
Inherit Vel.
0 0
Eject date
 0  58317.2762728
Finvars
  Finish BaseFunction
  Int 5
  Orbit True
  Vector  5180904390.99 857007312.812 7424844268.48
  Vector  -6146.80883306 -1016.89450704 -8789.16811499
  Double  3.98600439969e+014
  Double  58616.5200428
  Handle Earth
  Handle NULL
  Handle NULL
Select Target
 0 None
Autoplan
0 0
Plan type
0 1
Plan
0 0
Plan
0 2
Plan
0 0
Select Minor
 0 None
Manoeuvre mode
0 0
Base Orbit
0 0
Prograde vel.
 0  0
Man. date
 0  58112.4121571
Outward vel.
 0  0
Ch. plane vel.
 0  0
Intercept with
0 0
Orbits to Icept
0 0
Graph projection
0 0
Scale to view
0 0
Advanced
0 0
Draw Base
0 0
Finvars
  Finish BaseFunction
END_MFD

BEGIN_MFD Right
  TYPE User
  MODE TransX
END_MFD

BEGIN_SHIPS
3:DeltaGlider
  STATUS Landed Earth
  BASE Cape Canaveral:1
  POS -80.6758964 28.5227640
  HEADING 90.00
  RCSMODE 0
  AFCMODE 7
  PRPLEVEL 0:1.000000 1:1.000000
  NAVFREQ 0 524 84 114
  XPDR 6
  GEAR 1 1.0000
  PSNGR 2 3 4
  TRIM 1.000000
  AAP 0:0 0:0 0:0
END
END_SHIPS

BEGIN_VistaBoost
END
and ready for the eject burn...
Code:
BEGIN_DESC
A burn of 5579 m/s needed for the eject.
END_DESC

BEGIN_ENVIRONMENT
  System Sol
  Date MJD 58112.4670673098
END_ENVIRONMENT

BEGIN_FOCUS
  Ship 3
END_FOCUS

BEGIN_CAMERA
  TARGET 3
  MODE Cockpit
  FOV 29.59
END_CAMERA

BEGIN_HUD
  TYPE Orbit
  REF AUTO
END_HUD

BEGIN_MFD Left
  TYPE User
  MODE TransX
  Ship  3
  FNumber 5
  Int 1
  Orbit True
  Vector  198376.971889 -1662186.26583 6354168.71698
  Vector  -6931.96768778 3376.31624594 1099.61480406
  Double  3.98600439969e+014
  Double  58112.4652397
  Handle Earth
  Handle NULL
  Handle NULL
Select Target
 0 Escape
Autoplan
0 0
Plan type
0 0
Plan
0 1
Plan
0 0
Plan
0 0
Select Minor
 0 None
Manoeuvre mode
0 1
Base Orbit
0 0
Prograde vel.
 5  5578.54815698
Man. date
 5  58112.4742297
Outward vel.
 2  1
Ch. plane vel.
 4  57.285
Intercept with
0 0
Orbits to Icept
0 0
Graph projection
0 1
Scale to view
0 0
Advanced
0 0
Pe Distance
 0  6571244.85262
Ej Orientation
 0  0.435599274713
Equatorial view
0 0
Finvars
  Finish BaseFunction
  Int 2
  Orbit True
  Vector  -9315345742.87 22111751.3404 146809040340
  Vector  -31196.7682674 2242.06255066 -9155.99487234
  Double  1.32712838556e+020
  Double  58112.474229
  Handle Sun
  Handle Earth
  Handle Mars
Select Target
 0 Mars
Autoplan
0 0
Plan type
0 2
Plan
0 0
Plan
0 0
Plan
0 1
Select Minor
 0 None
Manoeuvre mode
0 0
Base Orbit
0 0
Prograde vel.
 0  0
Man. date
 0  58112.4657363
Outward vel.
 0  0
Ch. plane vel.
 0  0
Intercept with
0 0
Orbits to Icept
0 0
Graph projection
0 0
Scale to view
0 0
Advanced
0 0
Prograde vel.
 6  0
Eject date
 0  58112.4732801
Outward vel.
 6  0
Ch. plane vel.
 6  0
Finvars
  Finish BaseFunction
  Int 4
  Orbit True
  Vector  256207559.643 1077374677.49 6098386268.73
  Vector  -307.055288613 -1313.99803393 -7425.94396599
  Double  4.28282991638e+013
  Double  58308.3783381
  Handle Mars
  Handle NULL
  Handle NULL
Select Target
 0 Escape
Autoplan
0 0
Plan type
0 1
Plan
0 0
Plan
0 1
Plan
0 0
Select Minor
 0 None
Manoeuvre mode
0 0
Base Orbit
0 0
Prograde vel.
 0  0
Man. date
 0  58112.4665844
Outward vel.
 0  0
Ch. plane vel.
 0  0
Intercept with
0 0
Orbits to Icept
0 0
Graph projection
0 0
Scale to view
0 0
Advanced
0 0
View Orbit
0 0
Finvars
  Finish BaseFunction
  Int 3
  Orbit True
  Vector  101187247954 -6350804814.7 -184303009972
  Vector  19551.0700703 -527.423267935 6661.56154335
  Double  1.32712482783e+020
  Double  58317.8762348
  Handle Sun
  Handle Mars
  Handle Earth
Select Target
 0 Earth
Autoplan
0 0
Plan type
0 2
Plan
0 0
Plan
0 0
Plan
0 2
Select Minor
 0 None
Manoeuvre mode
0 0
Base Orbit
0 0
Prograde vel.
 0  0
Man. date
 0  58112.4670669
Outward vel.
 0  0
Ch. plane vel.
 0  0
Intercept with
0 0
Orbits to Icept
0 0
Graph projection
0 0
Scale to view
0 0
Advanced
0 0
Velocity.
 0  0
Outward angle
 3  2.48194860439
Inc. angle
 0  0.0217370286361
Inherit Vel.
0 0
Eject date
 0  58317.8762348
Finvars
  Finish BaseFunction
  Int 5
  Orbit True
  Vector  5177247188.59 858982366.66 7427133654.97
  Vector  -6109.26882673 -1015.31563898 -8745.27100999
  Double  3.98600439969e+014
  Double  58616.422016
  Handle Earth
  Handle NULL
  Handle NULL
Select Target
 0 None
Autoplan
0 0
Plan type
0 1
Plan
0 0
Plan
0 2
Plan
0 0
Select Minor
 0 None
Manoeuvre mode
0 0
Base Orbit
0 0
Prograde vel.
 0  0
Man. date
 0  58112.4664868
Outward vel.
 0  0
Ch. plane vel.
 0  0
Intercept with
0 0
Orbits to Icept
0 0
Graph projection
0 0
Scale to view
0 0
Advanced
0 0
Draw Base
0 0
Finvars
  Finish BaseFunction
END_MFD

BEGIN_MFD Right
  TYPE User
  MODE TransX
END_MFD

BEGIN_SHIPS
3:DeltaGlider
  STATUS Orbiting Earth
  RPOS -893308.86 -1103123.34 6415822.11
  RVEL -6854.658 3683.949 -321.010
  AROT 146.42 34.56 146.92
  AFCMODE 7
  PRPLEVEL 0:0.594959 1:0.988044
  NAVFREQ 0 524 84 114
  XPDR 6
  PSNGR 2 3 4
  TRIM 1.000000
  AAP 0:0 0:0 0:0
END
END_SHIPS

BEGIN_VistaBoost
END
 
Last edited:

Arrowstar

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Thanks, Flytandem! I'll check these out when I have time!
 

Arrowstar

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Hey Gary, I need to know what kind of trajectories you want for the Mars missions. Should we do direct for the unmanned stuff and the free return for the manned mission(s)?
 

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mikusingularity
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Can you take a look at that question and report back please pipcard?

This doesn't make any sense (JamesCook.ini)...
Code:
EMPTY_MASS=350000
FUEL_MASS=2400000
ISP=150000
When I plugged these numbers into http://www.strout.net/info/science/delta-v/, it gave me a huge value for Delta-V. (2832.09804 km/s)

What are the units for that config file? What is the ISP actually supposed to be? 1500 seconds? (then I get a Delta-V of 28.32098 km/s, which sounds more reasonable). Keep in mind that this is for a James Cook with nothing docked to it (and if it burns all of its fuel at once). It's more than enough for a trip to Mars and back (or even two trips).


I tried the same with the Deepstar.
Code:
EMPTY_MASS=20000
FUEL_MASS=300000
ISP=100000
Assuming that the ISP is actually 1000, I get a Delta-V of 26.556 km/s (nothing docked to the Deepstar and if it burns all of its fuel at once). So the Deepstar actually has less dV than the Cook?

---------- Post added at 01:36 PM ---------- Previous post was at 01:27 PM ----------

Okay, I checked on Orbiter and I let the Cook burn all it's fuel (with two Delta-gliders docked, keep in mind). I think it's more of a dV of about 283 km/s.
 
Last edited:

dgatsoulis

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@Pipcard The ISP in the case of the ini files you posted above is the exhaust velocity.

dv= ln((EmptyMass+Fuelmass)/Emptymass)*exhaustV

Without any other payload the James Cook has a dV of 309213,46 m/s (309,21346 km/s) and the Deepstar has 277258,87 m/s (277,25887 km/s)
 

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mikusingularity
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Size comparison time!

sizecomparison01.PNG


The Donovan-class Interplanetary Vehicle (the huge ship in the middle) has a similar dV to the UCGO Arrow, which is about 90 km/s.
If we're going to use the Arrow, know that it only has one docking port. Or maybe we should use the Deepstar. The Donovan is too big.

I wish I could develop my own interplanetary spacecraft, but I don't think I have enough time (so I won't even attempt it). I still haven't learned how to develop vessels.

Also, the [ame="http://www.orbithangar.com/searchid.php?ID=4642"]Long Shot[/ame] is overkill. It has no problem with two XR5s docked to it!
 
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garyw

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Without any other payload the James Cook has a dV of 309213,46 m/s (309,21346 km/s) and the Deepstar has 277258,87 m/s (277,25887 km/s)

I didn't want to use the deepstar because it had too much dV. I didn't realise the James Cook had even more. With that you really could take a holiday to the oort cloud. Oh well.

---------- Post added at 23:02 ---------- Previous post was at 23:01 ----------

Hey Gary, I need to know what kind of trajectories you want for the Mars missions. Should we do direct for the unmanned stuff and the free return for the manned mission(s)?

hmmm, good question.

Direct for unmanned, yes. Do we need free return for manned? We'll be taking a couple of XR2's so is a direct abort an option?

---------- Post added at 23:04 ---------- Previous post was at 23:02 ----------

The Donovan-class Interplanetary Vehicle (the huge ship in the middle) has a similar dV to the UCGO Arrow, which is about 90 km/s.
If we're going to use the Arrow, know that it only has one docking port. Or maybe we should use the Deepstar. The Donovan is too big.

We aren't. The James Cook was requested by the people participating so that's what is now going to be used.

I wish I could develop my own interplanetary spacecraft, but I don't think I have enough time (so I won't even attempt it). I still haven't learned how to develop vessels.

Doesn't matter. It's the James Cook now.

Also, the Long Shot is overkill. It has no problem with two XR5s docked to it!

So is the deepstar and james cook in my opinion thats why I wanted the Cosmos - 60km/s of dV.
 
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