Challenge ASATs are evil - an interception challenge

Wishbone

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The depicted mission represents the gradual escalation of the
hostilities between the Soviet Union and the United States...
Kill one spysat in the Molniya or sun-synchronous orbit.

You could try taking out the geostationary satellite but it is
quite hard.

The sun-synchronous Keyhole looks like the easiest target,
but please remember you're limited by launch inclinations less than
90 degrees, so either manual steering or plane alignment maneuvers
are in order.

The Molniya-orbit Ferret can be intercepted in the periapsis at
high relative speeds, which may prove too much for the ASAT terminal
autopilot, so use of Attitude MFD with lateral and vertical speed
nulling (Shift-Numpad 7) is recommended.

As this is interception and not rendez-vous, matching speeds during
terminal phase is not currently required.

In future versions the targets may be scripted to randomly evade
the ASAT.

Required extra addons: LaunchMFD ([ame="http://www.orbithangar.com/searchid.php?ID=2802"]Launch MFD - v 1.4.1 for Orbiter 2010[/ame]), TransX, Attitude MFD ([ame="http://www.orbithangar.com/searchid.php?ID=3165"]Attitude MFD V3.2[/ame]), and of course
the Project R-7: Early missions ([ame="http://www.orbithangar.com/searchid.php?ID=4419"]R-7 Early Missions[/ame]) by igel (Andrew Thielmann). Please read
carefully the manual for the R-7: EM package. In short, at scenario start
press M to disable auto-launch, press F8 to enter targeting dialog and wait
till MECO. If your rocket blows up you're entitled to re-run the scenario.

NOTE: the author of this scenario does not condone weapons in space.
Those who are interested can re-pack the scenario, switching sides
of the launcher and satellites, but are kindly requested to leave
the laucher site location, MJD and the ephemeris of the targets intact
for comparability.

This is a challenge, so please report 1) the target, 2) the MJD of launch,
and 3) the MJD of successful intercept, the sooner the better
(there are plans to delegate this function to a Lua script).

P.S. cannot add attachments in my old Opera, even with JS on.
Code:
BEGIN_DESC
The depicted mission represents the gradual escalation of the 
hostilities between the Soviet Union and the United States...
Kill one spysat in the Molniya or sun-synchronous orbit. 

You could try taking out the geostationary satellite but it is 
quite hard.

The sun-synchronous Keyhole looks like the easiest target, 
but please remember you're limited by launch inclinations less than 
90 degrees, so either manual steering or plane alignment maneuvers 
are in order.

The Molniya-orbit Ferret can be intercepted in the periapsis at 
high relative speeds, which may prove too much for the ASAT terminal 
autopilot, so use of Attitude MFD with lateral and vertical speed 
nulling (Shift-Numpad 7) is recommended.

As this is interception and not rendez-vous, matching speeds during 
terminal phase is not currently required.

In future versions the targets may be scripted to randomly evade 
the ASAT.
         
Required extra addons: LaunchMFD, TransX, Attitude MFD, and of course 
the Project R-7: Early missions by igel (Andrew Thielmann). Please read 
carefully the manual for the R-7: EM package. In short, at scenario start
press M to disable auto-launch, press F8 to enter targeting dialog and wait 
till MECO. If your rocket blows up you're entitled to re-run the scenario.

NOTE: the author of this scenario does not condone weapons in space. 
Those who are interested can re-pack the  scenario, switching sides 
of the launcher and satellites, but are kindly requested to leave 
the laucher site location, MJD and the ephemeris of the targets intact 
for comparability.

This is a challenge, so please report 1) the target, 2) the MJD of launch,
and 3) the MJD of successful intercept, the sooner the better 
(there are plans to delegate this function to a Lua script).
END_DESC

BEGIN_ENVIRONMENT
  System Sol
  Date MJD 45636.6605447462
END_ENVIRONMENT

BEGIN_FOCUS
  Ship Launchpad
END_FOCUS

BEGIN_CAMERA
  TARGET Launchpad
  MODE Cockpit
  FOV 50.00
END_CAMERA

BEGIN_HUD
  TYPE Surface
END_HUD

BEGIN_MFD Left
  TYPE Orbit
  PROJ Target
  FRAME Ecliptic
  ALT
  REF Earth
  TARGET Ferret
END_MFD

BEGIN_MFD Right
  TYPE Orbit
  PROJ Target
  FRAME Ecliptic
  ALT
  REF Earth
  TARGET KH-11
END_MFD

BEGIN_SHIPS
Polyot-2:r7_S\Polyot
  STATUS Landed Earth
  PRPLEVEL 0:1.000000
  =========== POLYOT vars 
  MISSION_HIT 
END
Fairing:r7_S\Fairing
  STATUS Landed Earth
  =========== FAIRING vars 
END
BlockB:r7_S\BlockBD
  STATUS Landed Earth
  PRPLEVEL 0:1.000000
  RELIABILITY 100
  =========== BLOCK BD vars 
END
BlockV:r7_S\BlockBD
  STATUS Landed Earth
  PRPLEVEL 0:1.000000
  RELIABILITY 100
  =========== BLOCK BD vars 
END
BlockG:r7_S\BlockBD
  STATUS Landed Earth
  PRPLEVEL 0:1.000000
  RELIABILITY 100
  =========== BLOCK BD vars 
END
BlockD:r7_S\BlockBD
  STATUS Landed Earth
  PRPLEVEL 0:1.000000
  RELIABILITY 100
  =========== BLOCK BD vars 
END
R-7:r7_S\BlockA
  STATUS Landed Earth
  PRPLEVEL 0:1.000000
  RELIABILITY 100
  =========== BLOCK A vars 
  PAYLOAD Polyot-2
  PREF 0.00 0.00 1.14
  PDIR 0.00 0.00 1.00
  PROT -1.00 0.00 0.00
  FAIRING1 Fairing
  FREF1 0.00 0.00 -1.80
  BLOCK_B BlockB
  BLOCK_V BlockV
  BLOCK_G BlockG
  BLOCK_D BlockD
  TRJ_ORBIT 479.00 220.00 58.10
  TRJ_BALLISTIC 49.43 0.00 0.00
END
Launchpad:r7_S\Launchpad
  STATUS Landed Earth
  PRPLEVEL 0:1.000000
  =========== LAUNCHPAD vars 
  LAUNCHER R-7
  TIMER -86327.92
  ORBIT 220.00 479.00 58.10
END
kmlWriter:r7_S\kmlWriter
  STATUS Landed Earth
END
Ferret:HST
  STATUS Orbiting Earth
  RPOS 2391058.54 27957905.92 34906426.03
  RVEL -1430.532 -857.722 -108.193
  AROT -137.96 12.42 125.05
  AFCMODE 7
  NAVFREQ 0 0
  ANT 0 0.0000
  HATCH 0 0.0000
  FOLD 1 1.0000
END
KH-11:HST
  STATUS Orbiting Earth
  RPOS -770740.20 236407.48 -6622449.85
  RVEL -1304.787 7607.453 423.023
  AROT 53.48 3.20 -11.86
  AFCMODE 7
  NAVFREQ 0 0
  ANT 0 0.0000
  HATCH 0 0.0000
  FOLD 1 1.0000
END
IMEWS:HST
  STATUS Orbiting Earth
  RPOS -36662827.54 -8287028.69 19104435.12
  RVEL -1518.536 1063.914 -2452.686
  AROT -35.99 -11.85 -3.24
  AFCMODE 7
  NAVFREQ 0 0
  ANT 0 0.0000
  HATCH 0 0.0000
  FOLD 1 1.0000
END
END_SHIPS
 
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Keyhole down

WARNING: the first rendition of the scenario under 2010P1 was buggy (R-7 was programmed to fail). Please re-save the file. I'll be posting my own results under 2010P1 soon.

EDIT: here goes. I started with the KH-11 as the target. Scenario starts on MJD 45637.4176, the launch is at 45636.6607 and the successful intercept is at 45637.4833. This means 18 hrs from start to launch and 19 hrs from launch to mission completion. About 56% of the fuel in the ASAT was left at intercept.
 

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Last edited:
Ferret ferrets no more

Launch: 45636.7218, Intercept: 45636.8416
That is 1h27m59s to launch, 2h 52m 30s to intercept. 56.6% fuel left at intercept.

Note: the Polyot is very easy and fun to ride :tiphat:
 

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I wonder what can be done with IMFD and 0.1x acceleration at intercept. If you don't hit the satellite, it doesn't count, right? Is there any minimum requirement for relative velocity at intercept? At least 1 km/s maybe?
 
I always aim at a hit-to-kill intercept, AFAIR the Polyot allows some miss distance (press spacebar to lock, L for terminal guidance and K for manual explosion), on the order of 20 meters (?). There's no minimum speed requirement as far as I know, too use 0.1x in high-speed cases, but TransX is enough for me.
 
These are all co-orbital kills aren't they? What about a retrograde kill?:P
 
Yup, tried to do that for the most part, cause right now am a bit afraid of 14km/s encounters even at 0.1x time acceleration, and am accustomed to using Launch MFD. Your idea makes sense though, would like to see how much time it saves.
 
I tried it a few times (not for this challenge) and even at 0.1km my misses were on the order of 10km+. I don't think launch MFD can handle that type of intercept.
 
Getting rid of geostationary sats.

Unfortunately I have no proper screenshots now, but let's just say that 14+km/s intercepts are doable, very thrilling and hard to get right - the inclination has to be guessed Buck Rogers' style. And yes, TransX and Attitude MFDs are the only thing needed to pull it off *after* you've made the ascent.

EDIT: another intercept, this time of the early warning satellite, aided and abetted by IMFD 5.5 in an out-of-plane burn, succeeded in abt 13 hrs after scenario start with the expenditure of all but 13% of the propellant. Pics will have to wait until I get to a browser that's supported by forum software. Geostationary sats are sitting ducks, though.
 
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