Shuttle Questions Q & A (Part 4)

• #340 by Susan27 on 24 Dec, 2007 21:50
• Merry X-mas everyone!
  
  

  Quote

  mkirk - 22/12/2007  9:53 AM
  These are the visual aim points...The concrete runways and KSC do not have them, and of the only TAL site to have them was Ben Guerir...
  Mark Kirkman

  
  1) Is there a special reason why the concrete RWYs dont have those aim-points?
  
  2) Just for understanding: At what scenario/situation the Commander targets towards the nominal aim-point and when at the close-in aim-point (low-energy?). What are the exact differences between these two procedures...?
  
  Thanks very much!
  
  Kind regards
• #341 by elmarko on 25 Dec, 2007 21:42
• As a follow up to Susan's question:
  
  When using the close-in aimpoint, is there a faster pull up to hit the same point down the runway, or is the runway touchdown point moved further along?
• #342 by Susan27 on 26 Dec, 2007 13:46
• Hi,
  
  I just want to know something about the voice-communication during reentry:
  
  1) I know that the crew usually transmits via TDRS-frequencies (satellite) to MCC. Is this way of com also kept during the whole reentry until touch down at SLF or is the voice-com switched to VHF (MhZ) prior to landing? If the latter, at what point (altitude) during reentry com is switched to VHF?
  
  At what "area" of VHF-band voice-com would be done, around 118-136 MhZ like "normal" air-traffic?
  
  2) Voice com. with the convoy commander: I learned that after the shuttle has come to a complete stop, NASA service vehicles will immediately "rush-out" on the SLF-RWY (33/15) for post-landing ground procedures:
  
  Does the commander calls the convoy commander via TDRS frequencies or via MhZ? If the latter, does the convoy commander also transmitts in VHF-band 118-136 MhZ or are there certain (military?) frequency bands reserved...?
  
  Thanks very much in advance!
  
  Kind regards
• #343 by Jim on 26 Dec, 2007 14:21
• 1,   air to ground is UHF. Most of the time, TDRSS is used.
  2.  there isn't comm between the orbiter and convoy until after the convoy is around the orbiter and after JSC is finished.  It is the same UHF
  
  A five-position UHF MODE rotary switch on
  panel O6 activates power to three UHF systems.
  The OFF selection disables all three systems.
  The simplex (SPLX) selection activates the 259.7
  MHz (296.8 MHz as backup) transceiver. The
  SPLX + G RCV selection activates the guard
  243.0 MHz emergency receiver together with the
  SPLX transmitter/receiver. The G T/R selection
  activates the guard 234.0 MHz transceiver for
  emergency voice communications through any
  available ground station and disables the SPLX
  transceiver.
  
  Mark can provide corrections
• #344 by Susan27 on 27 Dec, 2007 12:10
• Hi,
  
  I have these questions concerning the roll-reversals (RR):
  
  1) If I am correct there are 3 RR while deorbit. During the most part of the reentry the shuttle has an AOA of 40° and points with its belly towards the atmosph. (heat shield). How fast are those RR flown in reality, is this a slow smooth motion from right-bank to left-bank (and vis-versa) or just a quick movement (as fast as possible)?
  
  2) What is the reason that exact 3 RR are flown (no more, no less)?
  
  3) I learned that the shuttle flight crew has to be capable to fly all maneuvers which the DAP normally automatically flies (launch, deorbit etc.) manually for case of failures. But what about the very difficult deorbit procedure. There are so many details/data to observe very closely and strictly followed. Are there any helps on other cockpit instruments/MFDs/gauges/HUD which tell the crew for example, at what exact point begin to roll right/left, the exact bank rate, the AOA for every stage of the deorbit, speedbrake settings etc...?
  
  If so, which exact instruments show these kind of infos?
  
  4) Generally speaking:
  
  a) Do you know who "inventend" the whole shuttle reentry/deorbit procedure (RR, AOA etc.)? I think at least the basic concept has to be in mind of NASA long before STS-1...so in the early 1970`ies(?)...
  
  b) Is there a specific job-category at NASA (I am pretty sure...lol!) which calculates such procedures, reentry profiles...? How they are "called", are these e.g. the famous rockit-scientists or which "group" of technicians/scientists is especially responsible for the reentry stage...?
  
  Thanks very much for your help!
  
  Kind regards
• #345 by Jim on 27 Dec, 2007 12:25
• 1.  they are smooth.
  
  3.  The guidance moves needles on the ADI  show what the maneuvers should be and the astronaut flies to them.  The CRT's, checklists and placards describe when certain events should happen.  The crew can only back up the flight control system not the guidance system., the shuttle can't fly with guidance.
  
  
  4a,  Many people.  Including those who worked on lifting bodies
  4 b.  Flight dynamics personnel
• #346 by Susan27 on 27 Dec, 2007 12:42
• Thanks for that very quick reply, Jim!
  
  Concerning the Flight dynamics officers: Do you know what kind of degree those people have, I mean did they study physics (mechanics), astronomy or "where" do they come from...?
  
  Thanks again!
  
  Kind regards
• #347 by Jim on 27 Dec, 2007 14:08
• It is just orbit mechanics.
  Degrees are mostly engineering, aerospace, mechanical .  Maybe some physics degrees, not astronomy.
  
  The industry has many of these jobs.  JPL/GSFC and its contractors for orbital, interplanetary flights and planetary entries.  National Missile defense for interception engagements.  
  
  
• #348 by Naraht on 27 Dec, 2007 15:26
• Quote

  Susan27 - 27/12/2007  1:42 PM
  Concerning the Flight dynamics officers: Do you know what kind of degree those people have, I mean did they study physics (mechanics), astronomy or "where" do they come from...?

  
  During the early years of the space program, you had flight dynamics officers with all sorts of qualifications that weren't necessarily directly linked to orbital mechanics. Both Jerry Bostick and Jay Greene became heads of the flight dynamics division... Bostick had a degree in civil engineering, Greene in electrical engineering. Back then there was a lot of on-the-job training; there may still be, but I don't know as much about the way things work today.
  
  If you want to read more about what it's like to be a flight dynamics officer, look no further than Roger Balettie's website:
  
  http://space.balettie.com/index.html
• #349 by MB123 on 27 Dec, 2007 23:04
• Quote

  mkirk - 20/12/2007  12:27 AM
  
  

  Quote

  Susan27 - 19/12/2007  3:14 AM
  
  b) Concerning the push-to-talk transmit button on the CSS: Do you mean the small black knob directly located at the very top of the CSS or the bigger one at the left of this knob?
  
  Thanks very much in advance!
  
  Kind regards

  
  No, please refer to the diagram I attached for specific switch functions.
  
  Something I have always found amusing is what continuously using the trigger as a communications switch might mean to someone who leaves the Astronaut Corps to go back to flying fighters for the military.  I’m not sure how powerful the muscle memory would be after several years in the shuttle world (discounting T-38 time), but it would sure suck if you were simply trying to make a routine call to air traffic control from a plane like the F-15 or F-18 and you end up shooting some 20 millimeter rounds up your wingman’s tail pipe because you used the trigger instead of the throttle mounted transmit button.
  
  Of course it takes some additional switch throws (i.e. master arm on, etc) for something like that to happen in a fighter jet, but I always felt a strange twinge in my hand when it came to making Air to Ground transmitions in the Shuttle Mission Simulator with the RHC trigger.
  
  Mark Kirkman
  

  
  Hahahah your going to get me fired! I have to learn to laugh quietly...
• #350 by Susan27 on 28 Dec, 2007 11:11
• Thanks very much for all your excellent answers of my questions, guys!
  
  Kind regards
  
  Susan
  
• #351 by Susan27 on 28 Dec, 2007 11:21
• Hi,
  
  I have this question concerning the ball-bar during final flare at SLF:
  
  1) How does the ball-bar (light-system) for the Inner GS exactly look like? Are there 2 (or more) lights situated above another, side by side or how is this system built?
  
  And this concerning the wheel brakes of the orbiter:
  
  2) a) How are the wheel-brakes used by tre crew? Are there also feet-pedals like in commercial jetliners (Boeing, Airbus etc.) or is NASA using other systems here?
  
  b) Il learned that the CMD steers the shuttle after landing by use of a single brake, e.g. if the shuttle landed slightly at the right of the centerline he/she applies *only* left wheel brake. Is this correct so far?
  
  If so, is there kind of limitation for use of a single wheel-brake? I am asking because I see the danger that if applying a single wheel brake too strong or too long...the shuttle could skid an runs off the RWY to this side at all...(!)
  
  c) How "strong" are the wheel-brakes? I am asking because I think that the most brake-effect comes from the drag chute only. This way very strong wheel brakes wouldnt be neccesary at all...
  
  So, how fast would the vessel come to a complete stop by only(!) applying wheel-brakes...or other way, are the brakes stronger than in airliner jets?
  
  d) Is it correct that the wheel-brakes are only mounted at the main-gear wheels, and here at the  outer wheels of each wheel-pair (left/right)?
  
  Thanks very much in advance!
  
  Kind regards
• #352 by Jim on 28 Dec, 2007 12:30
• Quote

  Susan27 - 28/12/2007  7:21 AM
  
  Hi,
  
  I have this question concerning the ball-bar during final flare at SLF:
  
  1) How does the ball-bar (light-system) for the Inner GS exactly look like? Are there 2 (or more) lights situated above another, side by side or how is this system built?
  
  And this concerning the wheel brakes of the orbiter:
  
  2) a) How are the wheel-brakes used by tre crew? Are there also feet-pedals like in commercial jetliners (Boeing, Airbus etc.) or is NASA using other systems here?
  
  b) Il learned that the CMD steers the shuttle after landing by use of a single brake, e.g. if the shuttle landed slightly at the right of the centerline he/she applies *only* left wheel brake. Is this correct so far?
  
  If so, is there kind of limitation for use of a single wheel-brake? I am asking because I see the danger that if applying a single wheel brake too strong or too long...the shuttle could skid an runs off the RWY to this side at all...(!)
  
  c) How "strong" are the wheel-brakes? I am asking because I think that the most brake-effect comes from the drag chute only. This way very strong wheel brakes wouldnt be neccesary at all...
  
  So, how fast would the vessel come to a complete stop by only(!) applying wheel-brakes...or other way, are the brakes stronger than in airliner jets?
  
  d) Is it correct that the wheel-brakes are only mounted at the main-gear wheels, and here at the  outer wheels of each wheel-pair (left/right)?
  
  Thanks very much in advance!
  
  Kind regards

  
  1.  It is commercial system.  Details  should be available on the internet
  
  2.a.  The rudder pedals, just like regular aircraft
  
  2b.  There is nosewheel steering
  
  2.c the orbiter originally didn't have the drag chutes and still have to be able to brake without the chute.
  
  2d.  both innner and outer wheels have brakes
• #353 by Susan27 on 28 Dec, 2007 13:29

• Quote

  Jim - 28/12/2007  7:30 AM
  
  1.  It is commercial system.  Details  should be available on the internet

  What do exactly mean with "commercial system", a common VASI (2,3 -bar) situated at the left?
  

  Quote

  2b.  There is nosewheel steering
  

  Do you mean holding on the centerline of the RWY is only performed with the nosewheel steering and not with differential use of wheel brakes?

  Thanks again for helping!

   

  Kind regards

• #354 by Jim on 28 Dec, 2007 13:45
• Quote

  Susan27 - 28/12/2007  9:29 AM
  
  

  Quote

  Jim - 28/12/2007  7:30 AM
  
  1.  It is commercial system.  Details  should be available on the internet

  What do exactly mean with "commercial system", a common VASI (2,3 -bar) situated at the left?
  

  Quote

  2b.  There is nosewheel steering
  

  Do you mean holding on the centerline of the RWY is only performed with the nosewheel steering and not with differential use of wheel brakes?

  Thanks again for helping!

  Kind regards

  
  1  yes, these are used at other airfields
  
  2  both
• #355 by Susan27 on 29 Dec, 2007 11:21
• Thanks very much for your quick answers! Nice greetings to hopefully (compared to here) warmer Florida...
  
  Kind Regards
  
• #356 by kimmern123 on 29 Dec, 2007 20:46
• Why wasn't Columbia delivered with the HUD installed? Was it considered unnecessary for ensuring a safe flight and therefore they could launch her earlier than if she waited for the HUD to get installed?
  
  Also a follow up, how did the CDRs of Columbia on her first flight navigate when they didn't have the HUD? I guess they used the instruments on the flight deck, but I'd think it would be a distraction for the CDR to constantly check all the gauges while simultaneously flying a brick towards a safe landing?
• #357 by Jim on 29 Dec, 2007 22:13
• Quote

  kimmern123 - 29/12/2007  4:46 PM
  
  Why wasn't Columbia delivered with the HUD installed? Was it considered unnecessary for ensuring a safe flight and therefore they could launch her earlier than if she waited for the HUD to get installed?
  
  Also a follow up, how did the CDRs of Columbia on her first flight navigate when they didn't have the HUD? I guess they used the instruments on the flight deck, but I'd think it would be a distraction for the CDR to constantly check all the gauges while simultaneously flying a brick towards a safe landing?

  
  The orbiters were designed without HUDs.  HUDs were not commonplace when the shuttle was first designed.  The HUDs were a modification added later in the program.  
  
  HUDs are not a necessity for piloting an aircraft. The CDR's flew the Orbiters like every other aircraft without HUDs, which includes other high speed aircraft like the X-15, X-24, HL-10, M2F3 etc.
• #358 by kimmern123 on 29 Dec, 2007 22:30
• Okay, thanks a lot for the answers, Jim!
• #359 by DaveS on 29 Dec, 2007 22:30
• Does anyone know how the PCR door vertical torque tubes is attached to the orbiter payload bay doors when it is out at the pad?