ApolloHoax.net
Apollo Discussions => The Hoax Theory => Topic started by: Apollo 957 on January 26, 2017, 06:10:29 AM
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I'm aware that the Apollo astronauts, on trans-lunar coast, used the 'optics' (sextant) to determine position, compute course, and then apply correction.
To what extent did they have manual control prior to this? Was there any element of them actually 'steering' the craft at any point from launch to TLI?
I could spend a happy hour or two looking up the various documents, but I'm hoping someone who is certain of the answer already could summarise it in a short paragraph for me.
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First of all, the optical assemblies were mostly about determining attitude. Position was determined onboard by dead reckoning from periodic state vector updates from the ground. The ground can obtain a very accurate position by observing the direction of the radio signal over precise intervals, whether in Earth orbit or in the translunar orbit. The optics were rigidly aligned to the guidance reference platform by some extremely robust structure. Hence the optics could tell you if the platform had drifted by even a small fraction of a degree. With some math and careful observation, it would have been possible for the the crew to use the sextant to observe landmarks on Earth and reason about their position in orbit, but that was a contingency technique.
The extent to which the crew had manual control was simply the extent to which they wanted it. They could configure the flight controls to give them manual control over the SPS and the RCS, the latter being capable both of rotations and low-impulse translation. The system was fly-by-wire, but the control system could be configured to apply the hand-controller inputs in different ways. For example, in one mode you could deflect the hand controller and the ship would rotate at a speed proportional to the amount of deflection until you released the controller, whereupon the ship would stop. In another mode the rotational acceleration would be proportional to the degree of deflection, so that you could do things like set up a constant rotation rate. Finally, in "hard over" mode, the hand controller would fire the appropriate jets directly -- bypassing the fly-by-wire -- if the controller is deflected all the way in any direction.
For ordinary attitude control it was simply easier to punch the pre-planned attitude values into the digital autopilot and let it do its thing. But nothing prevented full manual control.
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Jay, it is my understanding that they didn't have any control prior to TLI since they are still attached to the third stage of the Saturn V. I could see RCS, but using the SPS engine with the LM directly below it would have not been good. Am I wrong about this? Could you clarify what control they would have had before TLI and why they would have used the RCS of the service module while still attached to the S-IVB while the J-2 is burning?
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Jay, it is my understanding that they didn't have any control prior to TLI since they are still attached to the third stage of the Saturn V. I could see RCS, but using the SPS engine with the LM directly below it would have not been good. Am I wrong about this? Could you clarify what control they would have had before TLI and why they would have used the RCS of the service module while still attached to the S-IVB while the J-2 is burning?
The S-IVB stage had its own RCS system consisting of two hypergolic APS modules that could provide three-axis control during coast phases when the J-2 wasn't burning and therefore couldn't provide gimbal control.
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So basically spam in a can until S-IVB separation.
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Jay, it is my understanding that they didn't have any control prior to TLI since they are still attached to the third stage of the Saturn V. I could see RCS, but using the SPS engine with the LM directly below it would have not been good. Am I wrong about this? Could you clarify what control they would have had before TLI and why they would have used the RCS of the service module while still attached to the S-IVB while the J-2 is burning?
The S-IVB stage had its own RCS system consisting of two hypergolic APS modules that could provide three-axis control during coast phases when the J-2 wasn't burning and therefore couldn't provide gimbal control.
Right Ok. So, they don't have any access (nor would they want access) to the service module systems until separation, and the RCS on the S-IVB is not going to do any massive course corrections or anything - is that a safe assumption?
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Whoops, I guess I misunderstood the implication of the question.
Yes, prior to TLI -- with the S-IVB attached -- the crew had very limited options for maneuvering. It was all through the APS and all under LVDC control, and there wasn't any manual control of the LVDC from the CM except insofar as a clever person could put the LVDC into alternate steering mode (where the AGC was used as the brains) and then use the normal cockpit controls to generate flight control signals in the AGC which would then pass to the S-IVB. The answer implied question, "Could the crew fly the S-IVB under manual control?" is a foggy "maybe, but probably not." The normal control loop was via the Instrument Unit transceiver, which meant radio control from the ground, and generally only during powered flight.
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First of all, the optical assemblies were mostly about determining attitude. Position was determined onboard by dead reckoning from periodic state vector updates from the ground. The ground can obtain a very accurate position by observing the direction of the radio signal over precise intervals, whether in Earth orbit or in the translunar orbit. The optics were rigidly aligned to the guidance reference platform by some extremely robust structure. Hence the optics could tell you if the platform had drifted by even a small fraction of a degree. With some math and careful observation, it would have been possible for the the crew to use the sextant to observe landmarks on Earth and reason about their position in orbit, but that was a contingency technique.
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I thought I had read somewhere that a sextant wasn't that accurate in determining course?
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I thought I had read somewhere that a sextant wasn't that accurate in determining course?
It isn't during most flight modes. In fact, nearly useless for that purposes. But prior to TLI the spacecraft would be in Earth orbit, and some determination of the spacecraft position can be obtained by using the sextant to sight landmarks on Earth as the CSM/S-IVB stack passes over them. This can translate into a set of observations that, taken together, could determine the spacecraft orbit if no other means were available. This and related techniques require using the sextant as a "dumb" sighting device, not really in the way it was designed.
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Cernan in the ALSJ (https://www.hq.nasa.gov/alsj/a17/a17.landing.html) : "I could have flown that Saturn V to orbit"
The launches - both from the Earth and from the Moon - were the only truly automatic phases of the mission, but we could take over and fly it manually to orbit. Aborting during Earth launch was the last thing I wanted to do, so I trained and planned. It was a lot more difficult at night than in the daytime because you didn't have horizons and things to look at; you had to look at the stars. We had several modes of failure that could have degraded systems. The worst would have been for all the guidance to fail so that you literally had to fly it by the stars. Now, I can never prove that I could have done it. But I did it a lot of times in simulators and really did - and still do - believe that I could have flown that Saturn V to orbit. It's one of those things where you say 'I hope it never happens; but I dare you. I'll show you. If you do fail, you just watch.'
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I always saw Cernan's claim of being able to pilot the Saturn V into orbit as a bit of a boast. Luckily, it never had to be tested.
The Apollo Guidance Computer on the CSM could determine position/trajectory in cislunar flight by having the crew sight the edge of the moon or earth. This was first tested during Apollo 8 with Jim Lovell as CMP, and his solutions essentially matched those produced by radio tracking from earth.
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I always saw Cernan's claim of being able to pilot the Saturn V into orbit as a bit of a boast. Luckily, it never had to be tested.
The Apollo Guidance Computer on the CSM could determine position/trajectory in cislunar flight by having the crew sight the edge of the moon or earth. This was first tested during Apollo 8 with Jim Lovell as CMP, and his solutions essentially matched those produced by radio tracking from earth.
Lovell had good experience that would be helpful in A13's trajectories, thrust to shorten the return and be within supplies in the spacecraft. The Law of Unintended consequences.? :)
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The Apollo Guidance Computer on the CSM could determine position/trajectory in cislunar flight by having the crew sight the edge of the moon or earth. This was first tested during Apollo 8 with Jim Lovell as CMP, and his solutions essentially matched those produced by radio tracking from earth.
Somewhere in my dead-tree library I have the paper that tested the degree of accuracy practically obtainable by this method. As I recall, the limiting factor was the dispersion in the optics for detection the edge of a bright object like the Earth in comparison with a nearby star. But yes, the bottom line is that a sextant is merely an object for measuring angles optically, and it can be put to a number of uses with enough imagination and mathematics.
Flying the Saturn V during powered flight is a much different animal than on-orbit maneuvers after SECO. Giving pitch and yaw commands from a hand controller via alternate command mode still washes those commands through the IU flight computer for necessary rate-limiting filtration, so you have very limited control anyway. The problem with rocketry in general is that it's extremely easy to exceed the structural limits for bending moments. You steer a rocket gently, and if gently isn't enough then all heads turn to the range safety officer. The bending moment measured on the Saturn V (and I want to say it was at one of the joints at the S-IC/S-II interstage) was well over 100 kN·m in normal flight. The last thing you want to do with a very large launch vehicle is fly it manually.
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How much, if any, torque is applied to the Saturn V from all the umbilicals being released?
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How much, if any, torque is applied to the Saturn V from all the umbilicals being released?
Negligible. The extraction force of some umbilical connectors can top 200 lbf on the Saturn V, but the connectors for launch vehicles always have some sort of stored-energy mechanism (spring, gas capsules, etc.) that provides the actual force. There's nothing pulling at the vehicle. All you have are incident forces from the separation actuators working.
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Flying the Saturn V during powered flight is a much different animal than on-orbit maneuvers after SECO. Giving pitch and yaw commands from a hand controller via alternate command mode still washes those commands through the IU flight computer for necessary rate-limiting filtration, so you have very limited control anyway. The problem with rocketry in general is that it's extremely easy to exceed the structural limits for bending moments. You steer a rocket gently, and if gently isn't enough then all heads turn to the range safety officer. The bending moment measured on the Saturn V (and I want to say it was at one of the joints at the S-IC/S-II interstage) was well over 100 kN·m in normal flight. The last thing you want to do with a very large launch vehicle is fly it manually.
My recollection was that the level of possible pilot control was higher during the second and third stage burns than it was for the first, during which basically any critical failure would trigger automatic abort faster than the commander could react. Is there any truth to this recollection or am I just fabricating memories?
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That's almost certainly true, as second and third stage flight occur outside the atmosphere so angle of attack isn't a problem.
As you accelerate through the atmosphere the aerodynamic drag increases with velocity squared, but it also varies linearly with air density, which decreases exponentially with altitude. So it increases to a peak called Max-Q and then drops again. This occurred at 78.9 seconds and 37.5 kilopascals on AS-503 (Apollo eight). Sea level atmospheric pressure is about 101 kPa, so you can see this is quite a bit of pressure.
But it falls just as fast as it rises, and by staging at 154 sec at an altitude of about 60 km, air density and therefore drag has decreased to essentially zero.
Maximum bending moment on that flight occurred at 74.7 sec, just before Max-Q, and was 6.78 meganewton-meters. That sounds like a lot, but the design load is 30 MN-m. This occurs near the bottom of the LOX tank in the first stage (the LOX tank is above the RP-1 tank). Bending moments tend to vary a lot from flight to flight due to differences in high altitude winds. It's why they release so many weather balloons before a launch.
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As you accelerate through the atmosphere the aerodynamic drag increases with velocity squared, but it also varies linearly with air density, which decreases exponentially with altitude. So it increases to a peak called Max-Q and then drops again.
Ok, so let me see if understand this correctly....
1. As the rocket accelerates from lift off, the velocity component of aerodynamic drag increases, and as its altitude increases, the air density component decreases.
2. In the first part of the flight, the velocity component increases faster than the air density component decreases, causing a nett increase the aerodynamic drag.
3. Eventually, the rocket reaches an altitude where the atmosphere is thin enough that the air density component begins to fall faster than the velocity component increases and that point is Max Q.
Wasn't it just after Max Q that Challenger exploded?
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The Emergency Detection System (EDS) was specifically designed to cause an automatic abort during the first two minutes of first stage flight when even small attitude errors can produce bending moments beyond what the structure can handle.
It used angle rates from the gyros in the IU and angle-of-attack sensors in the Q-ball (the very tip of the launch escape tower). It also watched for loss of electrical continuity between the CSM and IU, and for failure indications from the engines. A pitch or yaw rate exceeding 4 degrees/sec, or a roll rate exceeding 20 deg/sec would trigger an abort, as would the loss of 2 or more F-1 engines.
As far as I can tell, excessive angle-of-attack did not trigger an automatic abort, but it could be used as an indication for a manual abort. It was apparently measured by differential pressures sensed by the Q-ball. The abort limit was 22 kPa; the maximum reached on AS-503 was 4.8 kPa, again around Max-Q.
The crew disabled the EDS at about 2 minutes. They could still command a manual abort if they saw excessive rates. The pitch and yaw limits were relaxed to 9.2 deg/sec (from 4 deg/sec); the roll limit remained at 20 deg/sec. And of course the Q-ball was jettisoned along with the escape tower shortly into second stage flight.
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As you accelerate through the atmosphere the aerodynamic drag increases with velocity squared, but it also varies linearly with air density, which decreases exponentially with altitude. So it increases to a peak called Max-Q and then drops again.
Ok, so let me see if understand this correctly....
Yes, you have it right. Aerodynamic drag is 1/2 Cd rho A v2. Cd is the coefficient of drag, A is the cross sectional area, rho is the air density and v is velocity. Air density decreases exponentially with altitude.
The path through the atmosphere is pretty much determined by keeping the angle of attack as close to zero as possible; this is done by flying a "gravity turn" where the rocket is momentarily pitched over shortly after clearing the tower, then the gimbals are restored to near 0 degrees. Then gravity does the rest. The guidance system uses predetermined values during this time. Around staging, attitude is held constant. After staging, when the rocket is in vacuum, the guidance system is allowed to operate "closed loop" by steering it from where it is (in position and velocity) to where it wants to be.
Wasn't it just after Max Q that Challenger exploded?
Yes, but that was probably coincidental. It happened when the plume through the breach in the SRB had eaten away enough of the rear SRB strut that it was free to swing away and allow the nose to pivot into the LOX tank at the top. The bottom of the LH2 tank also fell away.
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Wasn't it just after Max Q that Challenger exploded?
Yes, but that was probably coincidental. It happened when the plume through the breach in the SRB had eaten away enough of the rear SRB strut that it was free to swing away and allow the nose to pivot into the LOX tank at the top. The bottom of the LH2 tank also fell away.
AFAIK on SRB ignition sections of primary and secondary O-rings were burned away but fortuitously an oxide plug formed and sealed the leak. After Max Q the stack encountered wind shear which caused bending moment which dislodged the plug and allowed hot gases to impinge the support strut and the External Tank.
Lurky
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Ok, so let me see if understand this correctly....
There's an extra complication in that the drag coefficient isn't a constant. It increases with angle of attack and is also a function of Mach number, most marked by a sharp increase as the Mach number approaches and passes through 1.
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AFAIK on SRB ignition sections of primary and secondary O-rings were burned away but fortuitously an oxide plug formed and sealed the leak. After Max Q the stack encountered wind shear which caused bending moment which dislodged the plug and allowed hot gases to impinge the support strut and the External Tank.
Lurky
From what I remember a piece/chuck of solid rocket propellant was the temporary plugging agent
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From what I remember a piece/chuck of solid rocket propellant was the temporary plugging agent
On the morning of the disaster, the primary O-ring had become so hard due to the cold that it could not seal in time. The secondary O-ring was not in its seated position due to the metal bending. There was now no barrier to the gases, and both O-rings were vaporized across 70 degrees of arc. Aluminium oxides from the burned solid propellant sealed the damaged joint, temporarily replacing the O-ring seal before flame passed through the joint.
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I stand corrected.
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Yes, that's correct; propellant combustion residue temporarily blocked the breach in the O-rings. As I recall, it was upper altitude wind shear that eventually broke the residue and let the plume re-emerge. It also took some time for that plume to burn through the strut holding the SRB to the ET and to cause the bottom of the LH2 tank to fail.
Speaking of max-Q, you can really hear the effect in the videos made within shuttle cabins during launch. At liftoff there is a lot of noise and shaking, as you'd expect. That settles down, but as the shuttle accelerates the wind noise grows very loud, reaches maximum at max-Q, and then tapers off again. It becomes eerily quiet in the cabin even before the SRBs burn out and are jettisoned, which is accompanied by a noticeable bang and a flash in the windows from the separation rockets.
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Maximum bending moment on that flight occurred at 74.7 sec, just before Max-Q, and was 6.78 meganewton-meters.
Thanks for the correction; you obviously looked up the values while I was trying to remember it. The value I had in my head was for a different parameter of the Saturn v.
Bending moments tend to vary a lot from flight to flight due to differences in high altitude winds. It's why they release so many weather balloons before a launch.
And indeed, as you allude to below, why post-Challenger launch criteria were amended to add more winds-aloft data.
As I recall, it was upper altitude wind shear that eventually broke the residue and let the plume re-emerge.
You recall correctly. The steering moments generated in response to the wind shear flexed the SRB more than usual and cracked the oxide plug loose. Regardless of how it may have behaved on the Challenger flight, engineers realized that their design limits for flexure on the field joints were not nearly conservative enough given the emerging knowledge of the joint's dynamic behavior, and this led to more stringent wind-shear requirements for launch. This had the effect of limiting the anticipated steering moments to those within the existing experience base, excluding Challenger.
Speaking of max-Q, you can really hear the effect in the videos made within shuttle cabins during launch. At liftoff there is a lot of noise and shaking, as you'd expect. That settles down, but as the shuttle accelerates the wind noise grows very loud, reaches maximum at max-Q, and then tapers off again.
This is in part a response to discontinuities in the forward section of the orbiter. The angle between the nosecone and the windscreen "traps" air, and the inset of the windscreen panes certainly doesn't help any with that behavior. There's a lot of dynamic pressure applied to the windscreen, and the inset produces turbulence. That's a huge roar just a meter or so from your face if you're in the commander or pilot seats. Boeing struggled with a similar problem for years; their airliner flight decks were notoriously noisy, for many of the same reasons. Even as late as on the 777, the particular way in which they traditionally formed the forward section of the fuselage included these discontinuities -- the result of structural methods to frame the windscreens. On the 777 tabs were added to the top surface of the nosecone in an attempt to redirect the airflow to the sides of the windscreen. Boeing wasn't responsible for the orbiter cockpit design, but the orbiter designers wrestled with similar problems and design constraints. With the 787 Dreamliner, the entire structural system of the forward section was redesigned from scratch and we were able to entirely eliminate the "Boeing roar" on the flight deck. The 787 windscreen is entirely conformal to the overall fuselage shape.
Also on the orbiter, the flow did not "stick" very well to the top of the flight deck as it came off the windscreen. There was intermittent flow separation right above/behind the windscreen that would have produced a fair amount of turbulence there as well, and that's yet another source of noise. The extremity of this behavior can be seen in this (http://www.feldoncentral.com/forumspp/data/13/spaceAtlantismach1.jpg) photo of the stack as it transits the sound barrier.
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The extremity of this behavior can be seen in this (http://www.feldoncentral.com/forumspp/data/13/spaceAtlantismach1.jpg) photo of the stack as it transits the sound barrier.
...and I have a new desktop background!
The Emergency Detection System (EDS) was specifically designed to cause an automatic abort during the first two minutes of first stage flight when even small attitude errors can produce bending moments beyond what the structure can handle.
It used angle rates from the gyros in the IU and angle-of-attack sensors in the Q-ball (the very tip of the launch escape tower). It also watched for loss of electrical continuity between the CSM and IU, and for failure indications from the engines. A pitch or yaw rate exceeding 4 degrees/sec, or a roll rate exceeding 20 deg/sec would trigger an abort, as would the loss of 2 or more F-1 engines.
I read a report a couple of years ago that concluded that if one of the outboard F-1s went-out during ascent, vehicle destruction due to bending moments would occur faster than the LES could fire. This makes some sense to my layman's mind: If I imagine the Saturn V stack as a 30-story building stressed with 4 gravities, and then one of the corner supports fails, I would think Really Bad Things will Happen Really Fast.
Using more formal terms, the report went on to predict that the spacecraft would be flicked from the tip of the rocket like whipped-cream from a spoon. In looking for ways to mitigate the lateral forces on the spacecraft, the report ironically pointed-out that these forces would be substantially less if the escape tower wasn't there providing leverage.
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Was that before or after the practice of "canting" the engines was begun? With canting, the four outboard engines are gimbaled slightly outward so the thrust vector from each one runs through (or at least closer to) the c.g. of the stack. The purpose is to minimize the disturbance if one of those engines should suddenly fail.
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...The angle between the nosecone and the windscreen "traps" air, and the inset of the windscreen panes certainly doesn't help any with that behavior. There's a lot of dynamic pressure applied to the windscreen, and the inset produces turbulence. That's a huge roar just a meter or so from your face if you're in the commander or pilot seats. Boeing struggled with a similar problem for years; their airliner flight decks were notoriously noisy, for many of the same reasons. Even as late as on the 777, the particular way in which they traditionally formed the forward section of the fuselage included these discontinuities -- the result of structural methods to frame the windscreens. On the 777 tabs were added to the top surface of the nosecone in an attempt to redirect the airflow to the sides of the windscreen. Boeing wasn't responsible for the orbiter cockpit design, but the orbiter designers wrestled with similar problems and design constraints. With the 787 Dreamliner, the entire structural system of the forward section was redesigned from scratch and we were able to entirely eliminate the "Boeing roar" on the flight deck. The 787 windscreen is entirely conformal to the overall fuselage shape.
Also on the orbiter, the flow did not "stick" very well to the top of the flight deck as it came off the windscreen. There was intermittent flow separation right above/behind the windscreen that would have produced a fair amount of turbulence there as well, and that's yet another source of noise. The extremity of this behavior can be seen in this (http://www.feldoncentral.com/forumspp/data/13/spaceAtlantismach1.jpg) photo of the stack as it transits the sound barrier.
Jay
I seem to remember reading somewhere that the flow of air between the Orbiter and the ET turned out to be more dangerous than designers had expected, and this alone might have caused the destruction of Columbia in the first Shuttle mission.
Is this true or am I mistaken?
With only a lay knowledge of aerodynamics I get the impression that some of the air passing off the nose of the ET would funnel between the Orbiter and ET, and in the process get compressed as the space narrowed, and on top of that be disrupted by the struts and pipes connecting the two. Would it be right to say that around the time of Max Q that airflow would be doing a pretty good job of trying to shake the two apart?
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I seem to remember reading somewhere that the flow of air between the Orbiter and the ET turned out to be more dangerous than designers had expected, and this alone might have caused the destruction of Columbia in the first Shuttle mission.
Is this true or am I mistaken?
There were a few overpressure instances that were not expected, so that part is true. Whether any of the post-flight anomalies attributed to the overpressure, including loss of TPS tiles, would have had catastrophic consequences if they had been more severe is anyone's guess.
With only a lay knowledge of aerodynamics I get the impression that some of the air passing off the nose of the ET would funnel between the Orbiter and ET, and in the process get compressed as the space narrowed...
Yes. There's an overpressure hotspot on the ET just forward of the bipod. This corresponds to the contour of the orbiter's forward underside. It's actually worse between the SRB nosecones and the ET, and those zones sort of blend together.
...and on top of that be disrupted by the struts and pipes connecting the two
The LOX feedline really doesn't really affect the flow much, which is a bit counterintuitive. There are some local discontinuities. But the bipod itself wreaks havoc. The overpressure doesn't extend farther aft on the ET than the bipod, which tells me there's a fair amount of turbulent flow aft of the bipod, and I'd attribute it to the bipod's effect on the flow. I think that has implications more for STS-107 than for STS-1.
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I'm aware that the Apollo astronauts, on trans-lunar coast, used the 'optics' (sextant) to determine position, compute course, and then apply correction.
To what extent did they have manual control prior to this? Was there any element of them actually 'steering' the craft at any point from launch to TLI?
LIFT-OFF [...]
At the center of the abort decision was the commander[....] If two cues from the EDS called for an abort[...she would] twist the handle in her left hand counterclockwise, activating the appropriate sequence to leave a malfunctioning launch vehicle behind[....]
The EDS was responsible for lighting a cluster of indicators that showed whether each engine was running at full thrust, whether the rocket was veering too fast and whether the Saturn's guidance system still knew which way was up. In the latter case, from Apollo 11 onwards, if the commander saw that the Saturn was incapable of guiding itself, she had the option of twisting the T-handle clockwise to pass control of the entire rocket to the spacecraft, and if that was also failing, she could manually guide it to orbit[....]
The Saturn V took care of its own guidance and [...]the crew had little to do except to keep a careful watch over it. This they did by running Program 11 on their computer, which displayed their speed, height and how rapidly that height was changing. P11 also drove their displays to show what their attitude should be throughout the ascent, so that any deviation could be seen. Should the commander have to take over control of the Saturn, she would fly it by following the the cues given by P11.
[...] The decision to control the Saturn V from its own instrument unit instead of using the capabilities of the command module's guidance system [...] was dramatically shown to be a fortuitous decision when the Apollo 12 was struck by lightning only 36 seconds after [lift-off....]
Later in the mission Dick Gordon laughed about the experience. "The launch was almost as good as me getting to fly the Saturn V into orbit." His was only the second Saturn equipped to allow the commander to fly manually into orbit - a contingency that, while never called upon, would have been welcomed by the hot-shot commanders within the astronaut corps.
Woods, W. David. How Apollo Flew to the Moon pp. 70-73.
All of this is in the book prior to the section entitled "SECOND STAGE".
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All of this is in the book prior to the section titled "SECOND STAGE".
In fact, it's all contained in the sub-section titled "Abort mode one-alpha".
The first 42 seconds of the flight up to a height of about 3 kilometres was flown in abort mode one-alpha[....]
Later in the mission Dick Gordon laughed about the experience.
Oops, I put Dick Gordon, the Apollo 12 CMP, rather than Pete Conrad, the commander.
Here's a link to the book's website: How Apollo Flew to the Moon (http://www.hafttm.com/author.htm)
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Sooo, if my take on this thread is correct...
In the event of Saturn V launch to orbit guidance system failure, it 'could' be flown manually, and this would consist of essentially "follow the pointer" on the ADI (is it still called that on rockets?), and keeping the line painted on the ball indicating attitude aligned under the needle indicating desired attitude, with inputs filtered to keep roll/pitch/yaw rates low, using the CSM's guidance system?
And in the event of an outboard F-1 failure, the stack would break up before the abort system could fire? Which of course would still trigger the LES tower, and the capsule would be pulled clear, even if not quite in the original direction?
(I recall reading a study done to determine that in the event of a high altitude stack breakup, the CM would aerodynamically assume either "bottom down, parachutes up" or "bottom up, parachutes down, impact ground" position. And the pilot would have maybe 20-40?? (It was a long time ago) seconds to orient it correctly. It was difficult to use outside references to do so, but they did discover a different method they relied on the capsule's response to control inputs when it first entered the atmosphere, and having something like a 15-20 second period where that could be used and the CM RCS was still powerful enough and the air thin enough to flip the orientation if it was the wrong one. Likely the main downside of the CM compared to the Soyuz capsule - Soyuz was aerodynamically self-righting, including on reentry. IIRC, it 'also' had to be, as it had no RCS in the capsule proper.)
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Yes, I believe your take on manual control of the Saturn V is pretty much correct. A lot still has to work for this to be possible, however. The CSM's guidance and control system and its communication links with the Saturn have to be fully functional, the rates have to be low enough (before atmospheric exit) that the emergency detection system hasn't already commanded an abort, and most importantly the Saturn's engines have to be functional. Given the redundancy in the Saturn's IU, a failure in an engine gimbal (like the dreaded "hardover") seems much more likely than a guidance failure that leaves the whole stack in a state where it can still be manually steered successfully into orbit.
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That's an interesting question of properly orienting the CM after an abort. Remember there were numerous abort "modes" for each phase of flight (you hear the Capcom calling them off to the commander as they step through them). Assuming you're talking about an abort on first stage flight around max-Q, the most dangerous time, my understanding is that the LES was expected to reorient the CM after pulling it free from the rest of the stack. Depending on air density it could use either the canards and/or the CM's RCS. It's also possible that deploying the drogue chutes would reorient the CM if it were falling nose first; they seem to be a popular way to stabilize the attitude of a falling object that's still too high and too fast for main chutes to be used.