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Subject: SPACE Digest V13 #231

SPACE Digest                                     Volume 13 : Issue 231

Today's Topics:
         NASA Headline News for 02/28/91 (Forwarded)
               Re: Numerology, theology
                   Re: Gaia
            Soviet Docking History

Administrivia:

    Submissions to the SPACE Digest/sci.space should be mailed to
  [e-mail].  Other mail, esp. [un]subscription requests,
  should be sent to [e-mail], or, if urgent, to
             [e-mail]

----------------------------------------------------------------------

Date: 5 Mar 91 05:11:03 GMT
From: [e-mail]  (Peter E. Yee)
Subject: NASA Headline News for 02/28/91 (Forwarded)

NASA announced today at the Johnson Space Center that the
shuttle, Discovery, will be rolled back next week to the vehicle
assembly building, destacked from the STS-39 package, and
transferred to the orbiter processing facility for replacement
and repair of the cracked hinge mechanism.

STS-39 payloads will be transferred to the payload changeout room
at launch pad 39-A.  The payloads will undergo routine servicing
and will remain at the launch pad until the return of the
orbiter, Discovery.

On Atlantis, a leaking thruster on the right hand orbital
maneuvering system pod is being tested.  The mid-body of the
orbiter is being closed out in preparation for next Tuesday's
scheduled roll out.

Routine systems tests are continuing on the orbiter, Columbia.

                   ***************************

As of late yesterday afternoon, the Galileo spacecraft was almost
33.5 million miles from the Sun.  Spacecraft health and mission
performance are excellent.

Last evening, the Magellan spacecraft and its radar system were
performing normally.  Spacecraft controllers believed they
already were seeing the effects of Venus' shadow, which they did
not expect to see until this morning.  According to a project
spokesperson, they were probably observing the effects of the
planet's atmosphere.

                  *****************************

The United States and Canada have signed an agreement to
participate in a 5-year RADARSAT Earth observation satellite
mission.  The launch of the Canadian-provided satellite is
currently manifested for June 1994, on a NASA-provided expendable
launch vehicle.  NASA and the National Oceanic and Atmospheric
Administration are the U.S. participants in this mission.  In
exchange for the NASA medium class expendable launch vehicle
services and data acquisition support for the satellite, NASA
will have full research access.  NOAA will obtain data for itself
and facilitate research and operational access for other U.S.
Government agencies.

                 ******************************










Thursday, 2/28/91
                        12:00       Liftoff to Learning Program

                        12:20 pm      Starfinder Program,
                                      "Gravity in Space"

                        12:35 pm      Back Space:  Apollo 14

                         1:00 pm      Black History Month Program

Replay of the above programming will be rerun between 6-8pm
tonight.

------------------------------

Date: Mon, 04 Mar 91 15:04:02 EST
From: "Paul M. Karagianis" <[e-mail]>
Subject: Re: Numerology, theology

On 28 Feb 91 Magnus Olson quotes an exchange between John Roberts and
someone else I'm unable to identify:

" >>      Will it someday happen that 2 + 2 != 4?
" >
" >Well, since you ask, yes, it could. :-)
" >A pure mathematical expression such as 2 + 2 = 4 exists by human definition,
" >and humans can change the definition any time they feel like it.
"
" This is true, but it's not quite that simple.

  ...followed by a lot of technical reasons why...

" THIS IS HIGHLY NON-TRIVIAL.

Huh?  He said definition.  When did base ten become so sacrosanct?
e.g.: 2 + 2 = 10, or 2 + 2 = 11 in base-4 and base-3.  To a non-
decimal oriented culture these expressions could represent truly
complex points of alien theology such as "2 quarts and 2 quarts is
a gallon" or "2 feet plus 2 feet is one and a third yards".

     +-------------- * standard disclaimers apply * --------------+
     |  "Let There Be Light..."     -        Bomb 22 <Dark Star>  |
     +------------  40o 43' 20" N  --  73o 47' 35" W  ------------+

------------------------------

Date: 5 Mar 91 00:36:48 GMT
From: sdd.hp.com!elroy.jpl.nasa.gov!jpl-devvax![e-mail]  (Larry Wall)
Subject: Re: Gaia

In article <[e-mail]> [e-mail] (John Roberts) writes:
:  - How has the earth been protected from the potential evolution of an
:    extremely efficient predator?

It hasn't, or haven't you been paying attention the last few million years?  :-)

I feel uncomfortable calling something an organism unless I can see some
selective advantages at work, and it's unclear at this point whether
the organization of our ecosystem will help it survive as it competes
against other ecosystems.

: What part of Gaia is its appendix? :-)

Hmm, something that uses resources but doesn't contribute to the good of
the whole, and is, in fact, occasionally destructive?  I'll have to
think about that one...  :-)

Larry Wall
[e-mail]

------------------------------

Date: 5 Mar 91 01:13:27 GMT
From: [e-mail]  (Adam R. Brody)
Subject: Soviet Docking History

In honor of the Russian Right Stuff broadcast on PBS last week,
I am reposting my Soviet Docking History.  Aerospace America was
going to publish it but I am growing impatient.  If Mark Johnson
from the Nat'l Association of Rocketry or anyone else has an interest
in publishing it, please let me know.  Otherwise, enjoy.

Soviet Docking Experience
    Any discussion of spacecraft docking operations would be incomplete
without mention of the accomplishments that the Soviets have had in this
area.  In 1991, the Soviets are inhabiting their eighth space station and as
of July 1990 have had 35 successful autonomous dockings in space.
(Friedman & Heinsheimer, 1990)  Cosmonauts inhabit the Mir space station
for many months at a time and unmanned vehicles automatically dock for
resupply.  Most of the information that follows was gleaned from the
Almanac of Soviet Manned Space Flight, by Dennis Newkirk (1990).
    The Soviets began contemplating spacecraft docking operations when
they realized these techniques were necessary for racing the Americans to
the moon.  Their first plan was an Earth orbital rendezvous (EOR) leading
to a lunar fly-by.  They were to use the same A-2 boosters and launch
facilities being developed for the Voskhod program and other unmanned
missions.  Each mission would involve five launches.  Soyuz V tankers
would automatically rendezvous and dock and then fuel the Soyuz B rocket
waiting in Earth orbit.  The manned Soyuz would dock with the fueled
rocket then ultimately be launched around the moon.
    By 1964 they realized they were not developing the docking
techniques fast enough to beat the Americans to the moon.  They therefore
decided to adopt a direct ascent profile, which involves launching directly
from Earth to the moon, thereby eliminating the need for docking.  After a
series of failures, Zond 5B achieved the first lunar fly-by and return in
September 1968.  The spacecraft contained plants, turtles, flies, and
worms.  Some modifications were needed, however, as the returning
capsule experienced between ten and sixteen g's, more than a human could
endure.  Zond 6 performed a similar mission in November but with g forces
reduced by one-half.  Technical difficulties delayed the December launch of
Zond 7A (which most likely would have been manned) by one month
allowing the US the first manned lunar fly-by with Apollo 8 in December.
    The rush to the moon hurt both the Soviets and the Americans
deeply.   In January 1967, during a launch pad rehearsal for Apollo 1,
Virgil I. Grissom, Edward H. White, II, and Roger Chaffee died in a fire.
Vladimir Komarov crashed to his death when the Soyuz 1 parachute
shroud lines twisted in April 1967.  These accidents delayed both the
Apollo and Soyuz manned launches for over a year.  "Apollo 1 and Soyuz 1
taught the world that victories in space would be neither easy nor cheap"
(Aldrin & McConnell, 1989, p. 172).
    In October 1967, two Soyuz vehicles, modified after the Soyuz 1
tragedy, tested and perfected automatic docking operations.  Kosmos
(Cosmos) 188 was launched three days after Kosmos 186 and completed a
rendezvous on the first revolution.  Kosmos 186 became the active vehicle
and docked with Kosmos 188, which was cooperatively maintaining a
stable attitude.  Cosmos 186 was the first Soyuz to have maneuvered in
orbit.  This was the first automatic docking and the first to be achieved by
unmanned vehicles.  Six months later, in April 1968, Cosmos 212 and
Cosmos 213 repeated this procedure.   Television cameras transmitted the
undocking to ground control.  These vehicles were essentially stripped
down Soyuz spacecraft and the procedure they pioneered is similar to
what is used today.  A brief description follows.
    Radar contact between the two spacecraft is established in the
capture phase.  Both vehicles align themselves to a common axis.  The
chaser vehicle closes with a range rate of about 2 m/s at 350 m.  This is
about six times faster than suggested by NASA's "0.1 % rule," which limits
approach velocity to no greater than 0.1% of the range per second (Sedej &
Clarke, 1985; Oberg, 1988).
    The target vehicle such as a space station then uses attitude control
rockets to maintain orientation in the mooring phase.  The chaser craft
extends a probe to effect a soft docking.  "The extended probe prevents the
airtight seals of the two spacecraft docking collars from being damaged if
the initial contact is hard or off center"  (Newkirk, 1990, p. 65).  The
vehicles complete soft docking when small latches on top of the probe
catch the center of the drogue.
    "In the docking phase, the active ship reels its probe in and the ship's
butt docking collars make an airtight connection" (Newkirk, 1990, p. 66).
Latches in both collars hold the spacecraft together so electrical
connections for communication and power may then be made.  With
Progress spacecraft, refueling connections also are consummated.  Springs
are used for disengaging.
    In October 1968, Colonel Georgiy Beregovoy attempted docking
maneuvers in Soyuz 3.  This was the first time the Soviets launched the
passive target vehicle, Soyuz 2, first as the U.S. did in the Gemini program.
An automatic system guided Soyuz 3 from direct ascent to a range within
180 meters.  Television cameras transmitted the image of the approaching
target to the Soviets.  This flight was intended to accomplish the first
Soviet manned docking but all docking attempts failed (Newkirk, 1990).
In one instance, ground control directed a maneuver calculated from data
transmitted by the rendezvous antennae on each vehicle (Baker, 1982).
    "Only 10 weeks after Soyuz 3, . . . the shortest gap between non-
related manned space missions to that time," (Clark, 1988, p. 50) the
Soviets launched Soyuz 4.  "The launch of Soyuz 4 and Soyuz 5 in January
1969 marked the first winter launch in the Soviet manned space
programme, suggesting that the flights had to be urgently completed"
(Clark, p. 51).  Another descendent of the lunar fly-by mission was the
first manned docking in January 1969 with Soyuz 5.  After practicing
almost 800 dockings in the simulator at Star City, Vladimir Shatalov
accomplished an objective of the failed Soyuz 1 mission, i.e., the first Soviet
manned docking.  In Soyuz 4 he flew a manual approach to within a few
kilometers of Soyuz 5.  He then activated the automatic system, which
reduced the range to 100 meters.  Shatalov then regained control and
docked during a live Soviet television broadcast.  This docking set a
precedent in that it did not occur during the first orbit.  The Soviets
announced the combined spacecraft "as the world's 'First Experimental
Space Station'" (Clark, p. 51).  Yevgeniy Khrunov and Aleksey Yeliseyev
used the opportunity to perform the first transfer from one spacecraft to
another.
    The Soyuz was then modified for use as a space station ferry.  Soyuz
10 and Soyuz 11 were the only flights with the original Salyut ferry.  The
most important change was the introduction of a crew transfer system,
which precluded the necessity to go EVA to board the station.
    The Soviets used Volga trainers to prepare for the docking
operations.  The Volga consisted of movable mockups of both Soyuz and
Salyut mounted on rails.  They would respond to commands made by the
cosmonauts.  A television view of the Salyut was presented to the Soyuz
model's periscope system to give the crew a simulation of an actual
approach (Clark, 1988).
    While manual control has been relegated to a back-up position for
unmanned supply vehicles, the Soviets have utilized manual control for
manned dockings to space stations.  This began with Soyuz 10, in April
1971, which brought the first crew of Vladimir Shatalov, Aleksey
Yeliseyev, and Nikolay Rukavishnikov to Salyut 1.  Salyut 1, mankind's
first space station, was launched in April 1971 aboard the Soviet Union's
most powerful space launcher, the D-1, and reentered the atmosphere in
October.  The Salyut assisted in the docking maneuver not only by
maintaining attitude control, but "also made four orbit changes to match
orbit with the approaching Soyuz" (Newkirk, 1990, p. 99).  At a range of
180 meters, Shatalov took over control from the automatic system and
performed a manual docking.  Problems, most likely with the Soyuz,
prevented the crew from boarding.
    The Soviets and the Americans both advocate manual back-up for
automatic docking maneuvers.  However the Soviets only resort to the
manual system upon failure of the automatic one, while the Americans
tend to use manual control whenever it is available, not just as a back-up
control mode.  Such is the case with shuttle (and other advanced aircraft)
landings where the mere existence of a manual control capability is cited
as a justification for using pilot control instead of the automated system.
    In an October 1970 meeting in Moscow, the Americans and the
Soviets started formulating plans for the Apollo-Soyuz Test Project (ASTP).
During a June 1971 meeting in Houston, "[Boris] Petrov expressed the
preference of the Soviet Academy of Sciences for a joint docking flight
employing the androgynous docking system" (Baker, 1982, p. 408).  This
could be accomplished either with a Soyuz docking with a Skylab/Apollo or
an Apollo docking with a Salyut/Soyuz.  The latter was established as the
baseline mission.
    In June 1971, Soyuz 11 was the next (and last) vehicle to dock with
Salyut 1.  The automated system reduced the range from 6 km to 100
meters.  Georgi Dobrovolsky then took over control at a range of 100
meters and a velocity of 0.9 m/s.  (This is nine times faster than suggested
by the 0.1 % rule.)  By 60 meters, he reduced the range rate to 0.3 m/s.
Dobrovolsky then completed the docking maneuver.  The crew became the
first to inhabit the first space station.  After a record 24-day mission, the
mission ended in disaster as the air escaped through an open valve 11
minutes before the craft reentered the atmosphere.  Twelve pyrotechnic
devices, used for separation, fired simultaneously rather than sequentially,
releasing a seal on the spacecraft's pressure equalization valve.  The
atmosphere escaped in approximately 30 seconds while the cosmonauts
were in the middle of a 60 second procedure to close the valve manually.
    Shatalov consequently replaced General Nikolai Kamanin as head of
the cosmonaut corp.  A redesign of the station was necessary but since this
would take longer than the Salyut's lifetime to complete, the station was
deorbited.  More than two years passed before the next manned mission.
    The Soyuz Ferry was created to bring crews to Salyut space stations.
It contained an automatic rendezvous and docking system known as Igla
or "needle".  As in earlier Soyuz docking missions, both spacecraft
maneuvered actively.  The Soyuz Ferry had its first manned flight, Soyuz
12, in September 1973.  Since both Salyuts 1 and 2 failed in the previous
year, this flight was able to only simulate transport to a space station.
(Salyut 2 most likely had an attitude control thruster stuck on and broke
up in orbit before it was manned.)
    Soyuz 13, launched in December 1973, was an independent mission
and did not dock with a station.  Soyuz 14 was the first operational use of
the ferry and took the only Salyut 3 crew to orbit in July 1974.
Automated rendezvous was used to reduce the range from 1000 meters to
within 100 meters.  Pavel Popovich then performed manual docking.
    This procedure of manual control takeover at approximately 100
meters continued with Alesksei Gubarev on Soyuz 17, January 1975.  Pyotr
Klimuk performed similarly in May 1975 with Soyuz 18B.
    Soyuz 19, better know as the Apollo-Soyuz Test Project, "was the
first Soviet manned launch ever whose time was announced in advance
and was the first to be televised live" (Newkirk, 1990, p. 140).  Apollo was
the active vehicle because of its greater fuel supply.  The Soyuz merely
had to maintain a fixed attitude toward the approaching Apollo, and match
roll rates.
    Soyuz 20 tested the Progress automated unmanned cargo transport
systems in November 1975.  Progress 1, however, did not fly until January
1978.  The Progress, based on the Soyuz, carried twice as much rendezvous
and docking instrumentation as the Soyuz Ferry.  Also, a second video
camera was mounted on the outside to give ground controllers a stereo
view of the automatic docking.  "Simultaneous transmissions of telemetry
from Progress to Salyut and the ground enabled both the control center
and the cosmonauts to assist with docking if necessary" (Baker, 1982, p.
524).
    Progress 1 took two days approaching Salyut 6 as Soyuz 20 had done
approaching Salyut 4.  Manned spacecraft typically perform the approach
in one day.  "Since the Progress was unmanned, the crew did not retreat to
the Soyuz during the docking as when the Soyuz 27 docked, they instead
manned the station's controls ready to maneuver away from the
approaching Progress in case of a malfunction" (Newkirk, 1990, p. 179).
Since the Progress was expendable, plume impingement upon it caused by
an emergency Salyut separation maneuver was not a concern.  None of the
Progress missions through May 1988 had any docking problems although
there were occasional problems with manned missions.
    The Soyuz-T then replaced the Soyuz Ferry.  It "included a new
computer system and was claimed to be more automated than the earlier
Soyuz variants; however, in flight the cosmonauts often had to take over
manual control when the automatic systems apparently malfunctioned
during docking manoeuvres" (Clark, 1988, p. 98).  Soyuz T-1 flew in an
unmanned configuration in December 1979.
    In June 1980, the Argon docking computer flew its maiden launch on
the first manned Soyuz T flight, Soyuz T-2.  Argon selects which of several
possible approaches to fly to a space station and then flies it with manual
override capability.  It similarly controls descent.  Its operation required
that the crew study computer programming.  This training may have saved
the mission as the automated docking system failed at a range of 180
meters from Salyut 6.  "This was a problem which would be regularly
repeated during Soyuz-T missions" (Clark, 1988, p. 120).  Yuri Malyshev, a
rookie, took over control and completed a successful manual docking.
Aleksey Yeliseyev explained that the crew and flight controllers had not
practiced the approach the computer selected so the crew decided to take
over control to be better prepared in the event of an emergency.  The crew
claimed the automated system would have been successful if given the
opportunity (Newkirk, 1990).
    Soyuz 38, the seventh international crew, was launched in September
1980 with the first black cosmonaut.  The automated system controlled not
only the rendezvous but also the docking.  The next manned flight, Soyuz
T-3, was launched in November 1980.  Its Argon automatic docking system
performed the docking maneuver from a range of 5 km.
    The Soviets' Mir "Peace" space station evolved from earlier Salyut
designs and was launched in February 1986.  The station contains five
docking drogues with a manipulator system that moves incoming modules
from the forward port where they have docked to a side port.  The Kurs
"course" docking system was incorporated into the forward port.  This
eliminated the need for attitude control by the station during the docking
maneuver (Newkirk, 1990).  Clark (1988) claims the rear port also was
outfitted with the Kurs system in addition to the old Igla system which
would accommodate Progress freighters.
    Mir's first crew was launched March 1986 on Soyuz T-15 with live
Soviet television coverage.  The Igla system controlled the approach to
within 200 meters of Mir's aft docking port, which was compatible with
Soyuz T and Progress.  Leonid Kizim then flew around to the forward port,
which was instrumented with the new Kurs system to be used with Soyuz
TM and Star modules.  The Soyuz was incapable of automatic docking at
the forward port but the laser range finder that was first used on the
Soyuz T-13 flight in June 1985 aided Kizim.  Kizim completed a manual
docking from an initial range of 60 meters.  In May, the crew performed
the first station-to-station transfer by flying over to Salyut 7 to reactivate
it.  Again, the hand-held laser range finder was used to generate range
data.  The automatic system was used from 5 km until Kizim took over
manual control and docked.  The crew returned to Mir at the end of June.
After the crew used the Igla rendezvous system to reduce the range from
200 meters, Kizim took over control at a range of 50 meters from the rear
docking port and maneuvered to dock at the forward port.
    The Kurs rendezvous system was demonstrated in May 1986 with an
unmanned Soyuz TM-1.  This system does not require target vehicle
transponders and can dock with a station at any relative attitude.  It
"makes contact with the station at a range of 200 km and docking lock-on
begins at 20 to 30 km distance" (Newkirk, 1990, p. 313).  Kurs presents
closing rate data from the docking radar to the cosmonauts.
    On March 31, 1987, the Kvant "quantum" module, the first to be sent
to Mir, was launched 1 degree out of plane with Mir in an approach similar
to that of Star modules.  During its approach to Mir on April 5, the
cosmonauts were suited upin the Soyuz TM in case of a collision.  The
spacecraft started its approach at 17 km distance using the old Igla
docking system.  At 500 meters distance, the Kvant's forward docking
camera was activated and the docking probe extended.  When Kvant was
only 200 meters from the station and preparing for final docking
maneuvers, Flight Director Ryumin radioed to the cosmonauts that Kvant
had lost its lock-on to Mir's docking transponders. . . . [Kvant drifted
slightly and] was rotating slightly as it passed within 10 meters of Mir."
(Newkirk, 1990, pp. 321-322)"The Kvant thrusters failed to slow down the
module and it flew past Mir" (Clark, 1988, p. 155).  Mission controllers
spent several days analyzing the problem during which time the Kvant
drifted to a range of 400 km.  Ground controllers brought Kvant back to
the vicinity of Mir.  The Igla automatic docking system was activated at a
range of 22 km.  Lock-on to Mir's docking transponder signal was
achieved; at a range of 1000 meters, the approach velocity was 2.5 meters
per second.  (This is 2.5 times the rate suggested by NASA's 0.1% rule.)
The relative velocity was decreased to .32 meters per second at 26 meters
(12.3 times the 0.1% rule rate of .026 meters per second).  Soft docking
was achieved within 21 minutes of Igla lock-on.
     During the docking of Progress 33 in November 1987, the Soviets
experimented with new station orienting procedures since the Igla system,
used by the Progress, required active maneuvering by the target vehicle.
Typical fuel expenditures for docking a Progress to Mir were
approximately 192 kg using the old system.  "The new Igla procedure
reduced this amount to about 82 kg" (Newkirk, 1990, p. 322).
     The first launch of the Progress M, a modified Progress, occurred in
August 1989.  It has an increased on-orbit stay time, "has an improved
automated docking system and also is able to transfer unused fuel to the
space station" (Rains, 1990b, p. 8).  The Progress M also possesses a return
capsule, which was successfully tested on mission Progress M5, in
November 1990 (Kiernan, 1990).Docking Failures
    Despite their great experience with docking both manned and
unmanned spacecraft, the Soviets have had several failures during docking
maneuvers.  Failures occurred with Soyuz 15 in August 1974, Soyuz 23 in
October 1976, Soyuz 25 in October 1977, Soyuz 33 in April 1979, and
Soyuz T-8 in April 1983.
    The failure of Soyuz 15 to dock with Salyut 3 was due either to a
repeated system failure to initiate the manual control phase at a range of
100 meters (Clark, 1988), or, "the automatic system malfunctioned twice,
pushing the ship out of control with excessive engine burns while only 30
to 50 meters from the station" (Newkirk, 1990, p. 128).  With a limited
battery and fuel supply, the vehicle had to de-orbit when the docking
failed.
    In October 1976, Soyuz 23 was aborted because of a malfunction in
the automatic docking system.  This occurred before the range of the Soyuz
to the Salyut 5 station was reduced to 100 meters.  Since the crew of
Vyacheslav Zudov and Veleri Rozhdestvenski were trained to take over
from 100 meters, but not before, the crew were forced to land as soon as
possible.  The manual back-up mode was not extensive enough to save this
mission.  As Tass reported, "the spaceship Soyuz 23 was put into the
automatic regime for the approach to Salyut 5.  Docking with the Salyut 5
station was cancelled because of an unplanned operation of the approach
control system of the ship" (Clark, 1988, p. 74).
    Viktor Grobatko flew a successful docking of Soyuz 24 in February
1977 after taking over control at a range of 80 meters.  The Soviets'
success was short-lived, however, as failure plagued Soyuz 25 in October
that year.  Vladimir Kovalyonok began the docking maneuver from 120
meters but five docking attempts to the Salyut 6 station failed due to a
faulty docking fixture on the Soyuz.  As the news release stated, At 07.09
[sic] Moscow time today [10 October] the automatic rendezvous of the
Soyuz 25 ship and the Salyut 6 station was begun.  From a distance of 120
metres, the vehicles performed a docking manoeuvre.  Due to deviations
from the planned procedure for docking, the link-up was called off.  The
crew has begun making preparations for a return to Earth.  (Clark, 1988,
pp. 104-5)While soft docking was achieved, hard docking enabling
electrical connections to be made was not.  This failure resulted in the
prohibition of all-rookie crews; Romanenko and Ivanchenkov from the all-
rookie back-up crew were each paired with veteran cosmonauts.
    Soyuz 33, with the fourth international crewPBulgaria, was launched
in April 1979.  The Igla system was implemented at a range of 9 km.
While approaching a range of 1 km from Salyut 6, the Soyuz automatically
fired its main engine for only three of its scheduled six seconds and caused
tremendous shaking.  The second attempt with Igla also failed when it
immediately shut down the engine.  As Tass reported, "During the process
of approach there occurred deviations from the regular mode of operation
of the approach correcting propulsion unit of the Soyuz 33 spacecraft, and
the docking of the craft with the Salyut 6 was aborted" (Clark, 1988, p.
114).  The Soviets determined the problem to reside in the Soyuz main
engine which was terminating thrust upon a failure to attain normal
combustion pressure.  This was the first on-orbit failure of the Soyuz
propulsion system.  The crew returned to Earth without docking.  This
amounted to the second failed visit to a Salyut for Nikolay Rukavishnikov,
the Soviet's first civilian commander.  The Soyuz 32 crew in Salyut 6 did
not receive supplies until Progress 6 brought them in May.
    Another failure occurred in April 1983 with the aborted Soyuz T-8
mission.  Although the launch shroud accidentally removed the rendezvous
radar antenna, mission controllers decided to violate their own rules and
let Vladimir Titov attempt an optical rendezvous from 10 km.  This had
never been done before by the Soviets and was particularly risky since
Titov later claimed he had not previously trained for manual approach and
docking.  Flight directors assisted Titov by computing the range rate after
Titov reported Salyut size estimates.  After a range of 330 meters was
passed, the Soyuz slipped out of contact with the ground.  Without his
range rate source, Titov was not sure of his closing rate.  Although he was
able to reduce his range to 75 meters with the aid of the Soyuz's floodlight,
he approached at too high a velocity and fearing a collision, fired thrusters
to change orbits and abort the docking  (Newkirk, 1990).
    There had been ten manned launches to Salyut 1, Salyut 3, Salyut 4
and Salyut 5.  Of these one had failed to reach orbit (Soyuz 18-1), two had
failed to dock with their Salyuts (Soyuz 15, Soyuz 23), one had docked but
the crew had been unable to transfer to their Salyut (Soyuz 10) and one
crew had perished during their return to Earth (Soyuz 11).  This left the
Soviets with a 50 per cent success rate, if we deem Soyuz 21 as a
successful mission even though it was terminated earlier than planned. . . .
During 1977-1981 there were 16 Soyuz spacecraft launched towards
Salyut 6 and of these only one failed to dock (Soyuz 33) and one docked
but the crew could not transfer (Soyuz 25); additionally, there were 4
launches of Soyuz-T craft, 12 launches of Progress craft and the Cosmos
1267 mission P all of which successfully docked with Salyut 6.  For Salyut 6
the success rate was 94 per cent.  (Clark, 1988, pp. 126-7)
Docking Recoveries
    Not all failures resulted in the loss of the mission.  During the Soyuz
T-6 mission in June 1982, Vladimir Dzhanibekov rescued the docking with
a manual maneuver after the automatic system failed.  After turning the
spacecraft around to perform the braking maneuver, at 900 meters from
Salyut 7, the Argon computer failed and would not realign with the station.
Dzhanibekov disconnected the computer and maneuvered the Soyuz along
all three axes to resume pointing at the station.  His successful docking
from such a far range under manual control was a major achievement
(Newkirk, 1990).  The regular failure of the Soyuz-T system during final
approach was usually followed by manual recovery and presumably led to
computer improvements in Soyuz-TM (Clark, 1988).
    Vladimir Dzhanibekov was no stranger to docking operations as this
was his third.  After five flights (he is the first, and as of 1986 still the
only, cosmonaut to fly more than three missions), he is the Soviet Union's
most experienced cosmonaut.  Dzhanibekov served as back-up commander
to Alexei Leonov for ASTP but did not fly until January 1978 with Soyuz
27 when he achieved the first double docking with a manned space station.
In March 1981 he flew his second flight in Soyuz 39 with Jugerdemidiin
Gurragcha.  In July 1984, on Soyuz T-12, he accompanied Svetlana
Savitskaya in the first extra-vehicular activity (EVA) by a female (Hillyer,
1986).
    As prime commander of the Soyuz T-13 mission, Dzhanibekov had
the privilege of testing a new manual docking system in June 1985.  The
primary purpose of this flight was to rescue Salyut-7 after it had lost all
power and was rolling aimlessly in space.  As Dzhanibekov says, There
were great difficulties with preparation for docking with this object.  The
station seemed to us as a dead space object and nothing more.  And
specialists were afraid that it would rotate in space at too high a speed in
three axes.  So we had to train and to find out this optimum way to
maneuver around the station to find the best light conditions of the Sun.
And of course to train our hand . . . everything had to be done manually.
(Hillyer, 1986, p. 17)
    Equipped with a laser rangefinder, Dzhanibekov compared the
measured range to Salyut-7 with the range computed by his spacecraft.  At
10 km, Dzhanibekov interrupted the automated approach to input Salyut 7
attitude data into the Soyuz docking computer.  The automatic approach
resumed until "3 km distance, at a rate of 12, and later 6 meters/second
when Dzhanibekov took control"  (Newkirk, 1990, p. 270).  At three km,
"there started to be a difference between our measurements and the
radar-calculated data.  So I had to take the handles and step in to direct
manually" (Hillyer, 1986, p. 17).  "At 2 km, the crew used a new optical
guidance system, hand-held laser range finder and a night vision
instrument, to see and measure distance to the station"  (Newkirk, p. 270).
At a range of 200 meters, Dzhanibekov nulled the approach velocity
because the sun was behind the station making visibility poor.  For 10
minutes he circled the station on damage patrol.  Then, in a roll-matching
maneuver, he docked with the station.  "(Later Dzhanibekov would say,
'Docking is like driving a seven-ton truck with fragile freight on an icy
road into a narrow gate at the end of this road')" (Kramer, 1990, p. 57).
The docking was successful and Dzhanibekov has similar opinions about
manual control as Buzz Aldrin: he shares Aldrin's skepticism about
automated systems and claims that manual control gives the ability to
"operate in [a] wider range" (Hillyer, p. 18).
    According to U.S., British, and Soviet sources, Salyut 7 will reenter in
late January or early February 1991 ("Salyut 7," 1990, p. 2).  The Salyut 7-
Cosmos 1686 will be the largest object to reenter since Skylab on July 11,
1979.  The Salyut's demise was accelerated by a peak in solar flare activity
in 1989.
    Admittedly, one of the main reasons for manual control is emotional
or political, namely, pilots would rather fly than watch.  However, the
successful rescues mentioned previously would not have been possible
without human intervention.
    Another recovery was made with Soyuz TM-5 (the thirteenth
international crew-Bulgaria), in June 1988.  Although the Kurs system
malfunctioned during the final approach, flight controllers diagnosed the
problem and a successful docking was completed within two days of the
launch.
     In June 1990, a docking recovery was achieved with an unmanned
vehicle.  Docking of the Kristall module with the Mir space station was
automatically aborted when a Kristall computer discovered a malfunction
in one of its attitude control thrusters.  Ground controllers used a backup
set of thrusters to complete the docking operation successfully (Rains,
1990a).

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End of SPACE Digest V13 #231
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