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Conference 7.286::space

Title:Space Exploration
Notice:Shuttle launch schedules, see Note 6
Moderator:PRAGMA::GRIFFIN
Created:Mon Feb 17 1986
Last Modified:Thu Jun 05 1997
Last Successful Update:Fri Jun 06 1997
Number of topics:974
Total number of notes:18843

558.0. "Shuttle Turn-around Time??" by BUFFER::CUMMINGS (Mr. Wizard) Wed Aug 16 1989 11:41

    I was wondering if anyone knew what the average/general turn-around
    time is now for a shuttle.  After it has returned to earth how long
    is it taking to prepare it for another launch?

    What was the original goal for turn-around time and how does that
    compare to actual practice?  My observations are that it takes
    about 30-45 days.

    [Author's Note:  After some preliminary searching, I was unable to
    locate anything which might discuss this.  Thus, Mr. Moderator,
    please feel free to move this to the appropriate place if need be.]

    Curiously,

    Steve
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558.1Original GoalsVOSTOK::LEPAGETruth travels slowlyWed Aug 16 1989 13:5811
    	The original turn around time goal was two weeks. I will have to do
    some checking to find the actual average turn around time but it is
    somewhere around 2 months or so. So much for meeting goals!
    	Just as an additional laugh, the orginal Space Shuttle launch rate
    goal was a launch a week or 52 launches a year. In reality, the present
    system can handle 9 launches a year and MAYBE as many as 14 launches if
    there was a 4 shuttle fleet and everything worked perfectly (which it
    hasn't to date).
    
    				Drew
    
558.2BALMER::MUDGETTdid you say FREE food?Thu Aug 17 1989 00:036
    Also isn't the goal based on the shuttle landing at the Cape? Is
    there any hope of the shuttle landing at the Cape again? They stopped
    because the brakes were not reliable enough has that been resolved?
    
    Fred Mudgett
    
558.3Cape LandingsVOSTOK::LEPAGETruth travels slowlyThu Aug 17 1989 11:2821
    Re:.2
    	Yes, the original turn around time goal included a landing at the
    Cape. But by landing at Edwards AFB, the Shuttle only loses about a
    week because of transportation time. Since the minimum turn around time
    is about two months (landing to next launch), this time has relatively
    little impact, in fact now it is included as part of the turn around
    schedule.
    	As far as landing at the Cape again, it is very unlikely. Part of
    the problem was the brakes as you mentioned but that problem has been
    solved. Presently the problem is Florida's unpredictable weather. In
    order for the Shuttle to commit to a landing at a particular location,
    a commit decision must be made about an hour before the planned landing
    time. The problem in Florida is the weather can drasticly and unpredictably
    change in an hour. I have spent some time in Florida and at the Cape
    and have seen severe thunder storms practically come out of no where.
    In the conservative post-Challenger era this sort of risk is
    unacceptable. So it is unlikely that a Shuttle will land at the Cape
    except in an emergency.
    
    				Drew
    
558.4Just wondering...57456::TRAPHAGANFri Aug 18 1989 12:4810
    I was just wondering, since weather patterns don't change all that
    radically over short periods of time (a few years, that is) wouldn't
    one assume that NASA would have thought of the weather problem
    BEFORE they built the landing strip at the Cape?
    
    Seriously, though, does anyone know why NASA built it while
    knowing that the weather conditions were difficult?
    
    JT
    
558.5Needed for RTLS at minimumPRAGMA::GRIFFINDave GriffinFri Aug 18 1989 13:5619
Re: .4

You'd want the strip there, at minimum, for an RTLS abort (that's when they
decide to return to the launch site - 0-1 engine condition).


I think the weather situation is certainly a good reason not to use it as
a primary landing site, but I believe the main reason is that the site
has some pretty nasty crosswinds, the shuttle doesn't fair well in 
crosswinds, and the pilots aren't thrilled about hitting that tiny little
spot on the ground with all these things going against him/her.

From a ground safety position, it also tends to make it an emergency site
as well.  If the shuttle misses the runway at Edwards, it lands on flat
ground and might even roll to a stop with the belly still off the ground.
Miss your mark at KSC, and you'll end up in a swamp, or worse.


- dave
558.6opinions alsoBALMER::MUDGETTdid you say FREE food?Fri Aug 18 1989 19:3911
    r3 Hey thanks for the summary of the reasons for not landing at
    the Cape. 
    
    r4 You know I've had this question about several things about the
    original shuttle. This weather problem seems to be just as bad on
    take off. It seems there is always some restriction they are up
    against. The Apollos all took off on time to like the seconds so
    they must have been able to handle bad weather more than the shuttle.
    It must be the wings?
    
    Fred Mudgett
558.7PAXVAX::MAIEWSKIFri Aug 18 1989 23:2911
  The launch can be held for weather down to a couple of minutes before
launch. It can then be restarted just about any time on short notice.
On landing, you have to make the go/nogo decision a good 1/2 hour before
landing and if you decide not to land you have to wait at least an orbit
and maybe an entire day.

  As for the Apollo, on an abort, the Atlantic was a much larger target
than the runway so they didn't need visibility. Still, they avoided launching
during storms.

  George
558.8RE 558.7RENOIR::KLAESN = R*fgfpneflfifaLSun Aug 20 1989 13:147
    	Well, APOLLO 12, launched in November of 1969, was struck by
    lightning twice on its way into space.  The electrical systems
    suffered a tremendous jolt, but it was not enough to stop the lunar
    mission. 
    
    	Larry
    
558.9Tile damageVINO::DZIEDZICSun Aug 20 1989 13:183
    I think the main concern with launching the shuttle during inclement
    weather is that of damage to the thermal protection system (the
    "tiles" on the orbiter).
558.10Shuttle PhilosophyVOSTOK::LEPAGETruth travels slowlyMon Aug 21 1989 09:5123
    Re: .4
    	The reason the landing strip at KSC was built as the primary
    Shuttle landing site was NASA's original philosophy towards the
    Shuttle. NASA wanted the world to consider the Shuttle as a robust,
    reliable, and cheap means of getting into space. The original goal was
    to have the Shuttle work as if were almost an airliner. NASA
    intentionally perpetuated this myth by misleading the government, the
    people, and even themselves. To claim that the Shuttle was anything
    less than origianlly advertised meant risking loss of funding (with
    hindsight, it may have been a better fate).
    	In reality, the Shuttle is a complex and fragile kluge that has
    no hope of attaining its original goals mainly due to the multitude of
    budgetary induced compromises made in its design and operation. The
    landing strip at KSC will forever be used by the Shuttle only as an
    emergency landing site (as in RTLS aborts) and as a landing strip to
    support such things as the landings of the 747 used to ferry the
    Shuttle. It is the perfect symbol of America's post-Apollo space
    program: non-goal oriented engineering programs that ulimately yeild
    senseless waste due to lack of leadership and funding.
    
    				Drew
                                                          
    
558.11Shuttle futureMAYDAY::ANDRADEThe sentinel (.)(.)Thu Jul 09 1992 09:1632
    
    I have a question,  what are the chances that the shuttle will work
    up to its originaly intented launch rate of one a week before it is
    replaced by the National Aero Space Plane ?
    
    NASP is a least 20 years away so the shuttle has time to improve.
    In order to become competitive with other launch systems, the shuttle
    has either to devide its costs by 5, or multiply its launch rate by 5.
    
    And I guess that increasing the launch rate maybe a bit easier then
    cutting costs.  As NASA gets more and more operating experience the
    shuttle technology should mature and stabilize... 
    
    This is is the current budget, not counting depreciation charges for
    already incurred developement costs: Do you thing it will look much 
    different 10 and 20 years from now ?
    

                                                     FY 1991     FY 1992

SHUTTLE PRODUCTION & CAPABILITY DEVELOPMENT           1,276.4     1,288.9

  Orbiter Operational Capability                        275.6       273.8
  Propulsion Systems                                    747.8       622.7
  Launch & Mission Support                              253.0       270.1
  Assured Shuttle Availability                                      122.3

SPACE SHUTTLE OPERATIONS                              2,790.0     3,023.6

  Flight Operations                                     801.5       912.5
  Flight Hardware                                     1,393.3     1,417.0
  Launch & Landing Operations                           595.2       694.1
558.12You ask easy questions...PRAGMA::GRIFFINDave GriffinThu Jul 09 1992 09:4517
    I have a question,  what are the chances that the shuttle will work
    up to its originaly intented launch rate of one a week before it is
    replaced by the National Aero Space Plane ?

0

    This is is the current budget, not counting depreciation charges for
    already incurred developement costs: Do you thing it will look much 
    different 10 and 20 years from now ?

Not really -- just bigger numbers with subtle fluxes in the distribution.
It also depends on how many orbiters are lost over the next 10 years or so
due to accidents (I'm unaware of airframe life expectencies now that they have
a few years of flying time).


- dave
558.13FASDER::ASCOLAROAnthony Edward, 5/5/92Thu Jul 09 1992 10:2514
    IMHO, 'they' will never launch the shuttle much more than one a month.  
    
    The reason is complex, but best expressed by fear.  What NASA
    administrator would push for a launch schedule more agressive that that
    recommended by the most conservative of advisors?  To lose a shuttle,
    again blamed on NASA being to agressive, would be the kiss of death for
    the shuttle program.
    
    Again, IMHO, we should damn near stop shuttle operations, postpone the
    space station and work towards NASP as fast as possible.  It is the
    only logical path.  The shuttle design is already something over 25
    years old, to wait another 20 years seems somewhat foolish to me.
    
    Tony