yee@trident.arc.nasa.gov (Peter E. Yee) (12/01/89)
Bruce Buckingham
Kennedy Space Center, Florida Nov. 29, 1989
KSC RELEASE NO. 125 - 89
MODIFICATIONS COMPLETED TO SPACE SHUTTLE LAUNCH PAD 39-A
Kennedy Space Center managers have declared Launch Pad 39-A
ready to support the December 18 launch of the Space Shuttle
Columbia on mission STS-32. The use of Pad A will be the first
since the launch of Shuttle mission 61-C in January 1986 and the
first since NASA's return-to-flight status last year.
Pad A was NASA's launch facility workhorse for the first 24
liftoffs of shuttle missions STS-1 through 61-C. The complex was
temporarily deactivated following the Challenger mishap as
mission managers chose to concentrate efforts to modify Pad B
first for the resumption of flight. Pad B has been the launch
facility used for the first seven missions beginning since the
return to flight in September 1988.
Prior to the shuttle program, Pad A was the embarkation
point for all but one of the Apollo/Saturn V missions which
carried American astronauts to the surface of the moon.
Since the Apollo program, Pad A has undergone several
significant changes. Replacing the launch umbilical tower, needed
to support and service the giant Saturn V vehicle, was a Fixed
Service Structure (FSS) and a Rotating Service Structure (RSS).
Both of these modifications are critical structures in the
current processing and launching of the Space Shuttle.
Geographically, Pad A is located about 18,000 feet from the
Vehicle Assembly Building. At the center of the pad is a 390 by
325 foot hardstand from which the shuttles are launched. From
this hardstand the Fixed Service Structure rises 347 feet to the
tip of the fiberglass lightning mast. The mast itself is 80 feet
tall. Also, there are 12 access platforms on the service
structure.
The RSS is a mobile service structure that pivots on a
vertical axis. It rotates 120 degrees, over the pad's flame
trench, and provides access to the orbiter for servicing of
payloads. The major payloads of the Space Shuttle are installed
into the RSS's Payload Changeout Room (PCR), an environmentally
controlled room that supports payload delivery and installation
into the orbiter's payload bay.
Following the Challenger accident, no facilities or ground
support equipment failures at the pads were identified as
problems during the ensuing investigation. However, NASA decided
to take advantage of the down time and implement modifications
planned prior to the accident as well as several improvements
suggested by the Presidential Commission on the Space Shuttle
Challenger Accident. In addition, improvements were made to the
pad as required by the redesigned solid rocket boosters.
As safety continues to maintain the highest priority in the
space program, the crew emergency egress system was a primary
target for modification. The extensive network of temperature and
flame detectors, water spray conduits and slidewire baskets was
improved. Also, two additional baskets were constructed and
modifications were made to the slidewire bunker area.
Another modification included work to the solid rocket joint
heater umbilical. This was an area listed for improvement by the
Challenger investigation panel. A new requirement was established
to maintain the SRB field joints at a constant temperature. Here,
a new umbilical was installed on the MLP to provide power to heat
the SRB joints to a temperature of about 75 degrees F.
In the end, a total of 138 modifications were made to Pad A
at a cost of about $50 million. Other modifications include work
in the following areas:
* on the Rotating Service Structure, improvements were made to
the environmental control system within the payload changeout
room to better keep out foreign contaminants;
* protection against the freezing of water services used at the
pad;
* modifications to improve the clearance between the solid rocket
booster's aft skirts as the Shuttle clears the tower during
ascent;
* installation of new weather protection systems (a series of
mobile panels) to guard the orbiter from wind swept debris and
other possible damage;
* installation of new elevators on the RSS;
* upgrades in the communications systems at the pad;
* modifications were made to service the orbiter Columbia's 5th
fuel cell cryogenic tank, needed for longer duration missions;
* installation of an additional payload clean access platform in
the PCR.
With the exception of the clean access platform and the
Orbiter Columbia's fifth cryo-tank modification, improvements to
Pad A are identical to those made to its twin, Pad B, prior to
the launch of STS-26.thomas@mvac23.UUCP (Thomas Lapp) (12/02/89)
> Geographically, Pad A is located about 18,000 feet from the > Vehicle Assembly Building. At the center of the pad is a 390 by > 325 foot hardstand from which the shuttles are launched. From > this hardstand the Fixed Service Structure rises 347 feet to the > tip of the fiberglass lightning mast. The mast itself is 80 feet > tall. Also, there are 12 access platforms on the service > structure. There is a fiberglass lightning mast? Can I assume that there is a wire running alongside the fiberglass mast, since the last time I checked, fiberglass was an insulator, not a conductor. - tom -- internet : mvac23!thomas@udel.edu or thomas%mvac23@udel.edu uucp : {ucbvax,mcvax,psuvax1,uunet}!udel!mvac23!thomas Europe Bitnet: THOMAS1@GRATHUN1 Location: Newark, DE, USA Quote : Virtual Address eXtension. Is that like a 9-digit zip code? -- The UUCP Mailer
henry@utzoo.uucp (Henry Spencer) (12/02/89)
In article <122.UUL1.3#5131@mvac23.UUCP> mvac23!thomas@udel.edu writes: >There is a fiberglass lightning mast? Can I assume that there is a wire >running alongside the fiberglass mast, since the last time I checked, >fiberglass was an insulator, not a conductor. That's correct. The fiberglass is just the structure of the mast. -- Mars can wait: we've barely | Henry Spencer at U of Toronto Zoology started exploring the Moon. | uunet!attcan!utzoo!henry henry@zoo.toronto.edu
nickw@syma.sussex.ac.uk (Nick Watkins) (12/04/89)
In article <122.UUL1.3#5131@mvac23.UUCP> mvac23!thomas@udel.edu writes: >There is a fiberglass lightning mast? Can I assume that there is a wire >running alongside the fiberglass mast, since the last time I checked, >fiberglass was an insulator, not a conductor. Yes you can. I think the mast is just to keep the wires (I think there are four) clear of, and above, the tower. The tower was originally added to the Launch Umbilical Towers in their mobile days, for ASTP if memory serves (I'm sure someone will correct me if I'm wrong). Nick -- Nick Watkins, Space & Plasma Physics Group, School of Mathematical & Physical Sciences, Univ. of Sussex, Brighton, E.Sussex, BN1 9QH, ENGLAND JANET: nickw@syma.sussex.ac.uk BITNET: nickw%syma.sussex.ac.uk@uk.ac