fastest time to iss and back?

[Keatah]

Just wondering what your fastest time from takeoff at KSC - dock with ISS for 10 minutes - then return to your starting point.. ?

What ship did you use?

I got about 3 hrs and 40 minutes (two orbits) and some dwaddling on final approach with hover and stuff. Xr-2 is the ship. 1st time trying a quick trip. I'm sure I can best that time. Kept RInc and DTmin pretty much at zero since insertion. (newbie alert!)


k

 

[agentgonzo]

I've done once-around docking operations (Fly to ISS, dock, undock and land in a single orbit). Used the DG-IV (never managed it with the shuttle). Time was about 2 hours I think. It used a lot of fuel to intercept and match speed with the ISS on the first orbit though.

 

[Keatah]

I just did that too.

Yeh, 2 hours is about right. I just did that. Exactly 2 hours from ignition to wheelstop! One orbit total with a 10 minute stopover at the space-a-station. (bringing back an injured crewman). Seems the bulk of time is wasted on de-orbit and re-entry. Especially when you limit the g's and heating.


I'll have to try the shuttle. But I can't imagine any margin for error here!

Ha!

 

[Thunder Chicken]

I'll have to try the shuttle. But I can't imagine any margin for error here!

You can do this with the shuttle, KSC-ISS-KSC in one orbit. I have a scenario to do just this with the fleet shuttle. The ISS has to be in a very narrow window (a few seconds off here or there and an intercept is not possible). I'll post it when I get the chance.

 

[Thunder Chicken]

Here is the scenario for Fleet Discovery to ISS, with instructions in description.

BEGIN_DESC
Launch window for direct ascent to intercept and dock with ISS. 

Launch at 230s to Tn. Use yaw to get relative inclination as close to zero as possible.

At MECO, begin OMS 1 burn to lift apoapsis to ISS orbit (use Sync MFD).

Use linear RCS to refine intercept time and relative inclination.

END_DESC

BEGIN_ENVIRONMENT
  System Sol
  Date MJD 52955.5937347221
END_ENVIRONMENT

BEGIN_FOCUS
  Ship Discovery
END_FOCUS

BEGIN_CAMERA
  TARGET Discovery
  MODE Cockpit
  FOV 50.00
END_CAMERA

BEGIN_HUD
  TYPE Surface
END_HUD

BEGIN_MFD Left
  TYPE Map
  REF Earth
  BTARGET Cape Canaveral
  OTARGET ISS
  TRACK ON
END_MFD

BEGIN_MFD Right
  TYPE OAlign
  REF Earth
  TARGET ISS
END_MFD


BEGIN_SHIPS
ISS:ProjectAlpha_ISS
  STATUS Orbiting Earth
  RPOS 11233.85 -6481066.91 1827007.25
  RVEL -7564.194 377.085 1359.264
  AROT 110.00 -10.00 80.00
  PRPLEVEL 0:1.000
  IDS 0:1 100 1:2 100 2:3 100 3:4 100 4:5 100
  NAVFREQ 0 0
  XPDR 466
END
Mir
  STATUS Orbiting Earth
  RPOS 3442050.86 5356958.73 -2178876.52
  RVEL 6461.340 -4185.408 -70.725
  AROT 5.00 10.00 15.00
  IDS 0:540 10 1:542 10 2:544 10
  XPDR 482
END
HST:HST
  STATUS Orbiting Earth
  RPOS 6056069.93 1602118.29 2112145.08
  RVEL -2468.411 -456.626 7375.862
  AROT -117.64 55.65 144.35
  NAVFREQ 0 0
  ANT 1 1.0000
  HATCH 1 1.0000
  FOLD 1 1.0000
END
LDEF:LDEF
  STATUS Orbiting Earth
  RPOS 5742508.47 1399609.31 -3011619.40
  RVEL 3334.163 1019.737 6937.887
  AROT 16.11 -45.98 -115.76
  NAVFREQ 0 0
  XPDR 470
END
Luna-OB1:Wheel
  STATUS Orbiting Earth
  RPOS 4340918.63 -309027.86 -5052562.80
  RVEL 5867.792 307.475 5027.167
  AROT 0.00 0.00 92.56
  VROT 0.00 0.00 10.00
  IDS 0:560 100 1:564 100
  XPDR 494
END
Discovery:ShuttleDiscovery
  STATUS Landed Earth
  BASE Cape Canaveral:11
  POS -80.6232502 28.6197342
  HEADING 0.00
  PRPLEVEL 0:1.000 1:1.000 2:1.000
  NAVFREQ 0 0
  CONFIGURATION 0
  CARGODOOR 0 0.0000
  KUBAND 0 0.0000
  PRADIATOR 0 0.0000
  SRADIATOR 0 0.0000
  GEAR 0 0.0000
  PAYLOAD_MASS 0.0000
  ARM_STATUS 0.5000 0.0000 0.0000 0.5000 0.5000 0.5000
  ARM_SEQ2 0.5000 0.0500 0.0500 0.5000 0.5000 0.5000
  ARM_SEQ3 0.5000 0.0500 0.0500 0.5000 0.5000 0.5000
  SAT_OFS_X 0.000
  SAT_OFS_Y 0.000
  SAT_OFS_Z 0.000
  TGT_HEADING  42.000
END
GL-01:DeltaGlider
  STATUS Landed Earth
  POS -80.6858943 28.5906644
  HEADING 330.01
  TANKCONFIG 1
  PRPLEVEL 0:0.995 1:1.000 2:1.0
  NAVFREQ 94 524 84 114
  XPDR 0
  NOSECONE 0 0.0000
  GEAR 1 1.0000
  AIRLOCK 0 0.0000
  PSNGR 2 3 4
  RCSMODE 0
END
END_SHIPS

This works within a fairly small time window, assuming all burns are made prograde. If you have a good head on your shoulders and can visualize your orbit and intercepts, you can tweak your intercept time (and recover the mission if you don't launch spot on time) by pitching up during your burns. But the more you pitch, the more you need to burn to null your relative velocity at the ISS for docking.

How successful you are in completing this all in one orbit depends on how quickly you can approach and dock. I use IMFD velocity match to determine approximate burn time to null velocity near the ISS (within 5 km), then I turn the ship toward the ISS reaccelerate and use the docking hud for a fast final approach. Last time I timed the mission, I docked at ISS 67 minutes after launch, just past Australia over the S. Pacific. Undocking immediately, dumping excess fuel and doing the reentry burn, I require almost all of the available crossrange capability to get back to KSC (but I stay well within dynamic loading limits for reentry). Main gear touchdown at the SLF occurs at 117 minutes after launch.

This is very nearly a Hohmann-type transfer where my apoapsis just touches the ISS orbit. I generally have about 76% fuel available at docking, given that there isn't much need for plane changes. This suggests that I could be much more aggressive during climbout and intercept the ISS earlier, burning more to get a earlier intercept, then burning more to null the relative velocity.

A highly unrealistic mission for the real shuttle, but a very fun challenge in Orbiter.

 

[Dr Pepper]

I know it probably sounds like I'm BS-ing, but my best time was about 20-30 minutes. I admit, I got extremely lucky, but it was still pretty cool. I was in the regular old Deltaglider, sitting at KSC. I was watching the ISS's orbit drift over me, and when it did, I took off (southeast, not northeast). My intention was to get into a 200-250km orbit and slowly work my way to a rendevous with it. However, once I got into orbit (which was a little high), I decided to take a look outside, and behold, the ISS was about 10-15km above me, slowly drifting (it was close enough to me that I could see the yellow tag). I was safely docked by the time we went around South Africa. I was never able to recreate it, though. Should have got a screenshot...

Other than that, my best was about 2-3 orbits or so. I usually take my time with a rendevous.

 

[eveningsky339]

My time is about 3 hours. But I recall one forum member who made it in about five minutes-- when he reached the end of his orbital insertion burn the ISS impacted him, port to port. It must have been a one in a billion chance.

 

[Omhra]

Seems like there are an 10 minute window and 30 minute, for direct ascent..
Then after that it takes 90 minutes minimum and lots of fuel or 2 orbits with good fuel conservation.

 

[kdridders]

Fastest

666 seconds when timed and executed to perfection - Deltaglider
I needed to keep modifying a scenario for the right launch window etc

 

[Shadow Addict]

My time is about 3 hours. But I recall one forum member who made it in about five minutes-- when he reached the end of his orbital insertion burn the ISS impacted him, port to port. It must have been a one in a billion chance.

oh wow.

My fastest time doesn't count cause I've only done it once and that was from orbit, not from KSC.

 

[Urwumpe]

If effectivity and realism is not needed, you should do it in about 25 minutes... direct ascent against the direction of travel of the ISS with HARD docking (slowing down is for cowards), and then deorbit immediatly into a retrograde trajectory, so you not only fall back, but accelerate towards Earth.

 

[Omhra]

I uploaded a couple of 30 minute ascents to ISS.

One is really pushing The limits on the XR2 and one is more relaxed...

over at.

http://www.orbithangar.com/acc_viewaddon.php?ID=3691

 

[synonys]

I done a fast docking from KSC with both the Shuttle and DGIV. I got about 1000s with both, the limiting factor for me is docking, its too slow I need to learn how to dock without instruments.

For getting back to KSC, thats limited because of the orbital times and reentry.

 

[agentgonzo]

If effectivity and realism is not needed, you should do it in about 25 minutes... direct ascent against the direction of travel of the ISS with HARD docking (slowing down is for cowards), and then deorbit immediatly into a retrograde trajectory, so you not only fall back, but accelerate towards Earth.

Are you suggesting docking with the ISS at effectively twice orbital speed, so 14.2km/s?

I'm liking your thinking. Does orbiter have any restrictions on docking speed? Thinking about it, the even if it doesn't, you'll have to be within 1m of the docking port at the timestep that the distance is checked, which at 14.2km/s is very unlikely. Nice idea though.

 

[Urwumpe]

I'm liking your thinking. Does orbiter have any restrictions on docking speed? Thinking about it, the even if it doesn't, you'll have to be within 1m of the docking port at the timestep that the distance is checked, which at 14.2km/s is very unlikely. Nice idea though.

Well, you have to be within about 30 cm, which makes it even harder (I tested the stuff in SSU, for the ODS, which made the ODS not simpler at all).

But still... at 100 fps, which you can achieve, you only travel 140 m / frame. you chance is thus only 1:420...

 

[agentgonzo]

Not sure about getting back, but I've just done KSC-ISS in about 11 minutes (XR2). Not a lot of fuel left at the end of it.

---------- Post added at 18:44 ---------- Previous post was at 17:36 ----------

Improved that last time. Docked ISS in a little under 10 minutes, then immediate undock and fired the engines prograde-and-downwards to speed up. Inverted flight in the upper atmosphere at about 11km/s. Messed up a bit coming into the cape and overshot by a couple of hundred km. Landed and wheelstop a gnat's whisker over 1h 20m after launch.