If vehicle naming is going to happen the way it happened in the Apollo missions then it is really up to the crew. If a Japanese/Russian etc member of the crew suggests a name that is from their heritage and the rest of the crew likes it then that name will be used unless for some reason NASA management has a big issue with it.
If vehicle naming is going to happen the way it happened in the Apollo missions then it is really up to the crew. If a Japanese/Russian etc member of the crew suggests a name that is from their heritage and the rest of the crew likes it then that name will be used unless for some reason NASA management has a big issue with it.
Why sentimentality it would be nice. However none of the Apollo crews named either the LM or CM after a specific person. They had a closer connection to these 3 astronauts than any of the current astronauts would have (Except for John Young). I am not sure if any of the crews would realistically want to do this.
Not to mention, it's kind of creepy. Respectful, worthy names these are, yes. But wouldn't you worry the mission with these names would be kind of--jinxed?
Oh, of course not! Jinxes are silly superstitions; the space program is a triumph of reason! Just look at all the occurrences of the number "13" in the third mission to the Lunar surface, and how the astronauts joked about it, and nothing bad...oh wait...
Part III, Post 18: Boeing-Grumman and the design and testing of the Artemis Altair lander
Good afternoon everyone! It's that time once again, so here we are. Last week, we covered the joint Russo-American Phobos sample return mission, Phobos Together. This week, we're moving back towards the efforts aimed at another, closer moon. This post is one that's been a long time coming, but I think next week's may be slightly more hotly anticipated. Anyway, without further teasing, let's be about it...
Eyes Turns Skyward, Part III: Post #18
By the mid-1990s, Boeing’s position in the space industry had grown to one that other companies, be they existing competitors or new upstarts, were well justified in being envious of. With an effective state-sponsored monopoly in large launchers due to ongoing NASA and DoD support for the Saturn Multibody family, and the approaching promise of Artemis flights on the Heavy variant of the booster, Boeing was in the attracting position of having guaranteed and stable profits in its space division, even before it had clinched the Artemis lander contract with the purchase of Grumman and its acquisition of that company’s talent and experience.
Even the most stable monopoly brings its own challenges, however, and in this respect Boeing’s position was perhaps not quite as desirable as entrepreneurs competing with the emerging Internet boom for venture capital might have wanted to believe. With the Saturn Multibody uncompetitive in the commercial market due to excessive size and relatively high per-launch costs, Boeing-Grumman possessed no entrant in the rapidly growing and, as Lockheed was showing, profitable commercial market. Reliable and reasonably cost-effective for large governmental payloads like Freedom resupply and rotation missions or military spy satellites, even the smallest Saturn variant faced the same problem as Vulkan in competing for commercial dollars, being too large for even the largest commercial satellites. Moreover, unlike the cash-strapped Russian program, to whom selling commercial Vulkan was very nearly a matter of life or death, Boeing’s guaranteed governmental contracts ensured that Saturn would always have a nice, stable cash flow, with a virtual floor of nine flights per year, shooting up to ten or eleven in some years. With Artemis, requiring a further nine cores per year, looming on the horizon, there was even less pressure for Boeing to try to compete; even if they wanted to, their manufacturing operations at Michoud would be near their limit at 18 cores per year, and for all but the most lucrative and long-term contracts the expense of expanding their operations would outweigh the revenue possible from more flights.
Under these conditions, Boeing’s management was largely content to let the space division run itself, choosing instead to focus attention on the highly competitive airliner market, where they were facing severe pressure from Airbus, Lockheed, and McDonnell Douglas, on one side, and smaller firms like Bombardier on the other, or the upcoming Joint Strike Fighter contract, possibly worth a trillion dollars or even more over the next several decades. Indeed, their purchase of Grumman had been largely intended to improve their positioning for this competition, whose winner would likely dominate American tactical fighter production--and therefore export markets for American fighter aircraft--for decades to come. Compared to the serious competition they were facing in both sectors, the stable, profitable, and safe space market seemed worthy of little focus from the greater corporate entity.
To their customers, of course, Multibody was an important part of their space operations, and whatever shortfalls in attention Saturn might have suffered from Boeing, it certainly lacked none from NASA and the Air Force, especially as Artemis continued to advance as a program. In order to achieve the best possible performance from the Saturn Heavy in its role as the critical Artemis launch vehicle, Boeing was tasked by NASA with performing its own version of the “interim improvements” already undertaken by McDonnell on the Delta 4000 family. Compared to the massive overhaul given to Delta, though, Saturn’s facelift was minor, mainly focusing on production streamlining, the introduction of improved models of the J-2 second stage engine, and the replacement of the aluminum skin of the S-IVB and C upper stages with lighter-weight aluminum-lithium alloys. Altogether, it was enough to push the payload of the Saturn H03 to over 80 tons, increases eagerly put to work by Artemis’ mission designers.
Of course, one of the design bureaus benefiting most from the changes was Boeing-Grumman’s own Bethpage spaceflight division, inherited from Grumman, which retained its responsibility for the design of the Artemis lunar lander. The task of the lander design was complicated by the fact that, like the original Apollo lander, it was really not one but two spacecraft: the descent stage and the ascent stage. Even compared to the Lunar Module, however, the new design would require an unusual amount of independence between its two parts, driven by the fact that the two stages had their own crucial and separate missions. Unlike Apollo’s descent stage, Artemis’ would also be used independently for cargo flights, and therefore require its own attitude control, gyroscopes, radar, and computer systems to allow it to land autonomously on the surface of the moon at sites precisely selected from orbital imagery that the international flotilla of precursor probes would provide. Meanwhile, the ascent stage would have a crucial life-support role through all the stages of the flight, serving not only as the sole transport vehicle for the journey to and from the Moon to L-2, but also as a key extension of the living space available within the Apollo itself on the voyage to and from the Earth. Both stages would also need to be much more capable as rockets than the original Apollo LM, in order to travel all the way to and from the Apollo capsule waiting patiently at L-2.
Additional challenges came with the fuels required for the trip. While Bethpage had recent experience with hydrogen-fueled landers, the need to store cryogenic fluids for the entire coast to the moon was a new challenge, requiring the solution of new problems in insulation and thermal management to ensure adequate supplies of these fuels throughout the mission. With the higher specific impulse of the new RL-10-A4 engines being key to the mission design, however, these problems had to be solved if Artemis was to succeed; and lurking in the back of the mind were always the similar but far greater challenges posed by Mars missions, even if NASA was not officially pursuing the Red Planet. Three of these engines would be fitted in a line on the bottom of the descent stage, with all three used for the powered descent initiation (PDI) burn which would slow down the lander, bringing it out of its trajectory from Earth or L-2 and setting it on course down to the surface. However, for the final part of the descent to touchdown, firing all three engines would require excessively high throttle ratios, so the plan was to proceed to touchdown only on the center engine or (if that engine failed to restart) on the paired outer engines. Despite this theoretical redundancy, ensuring that restart would be reliable and guaranteed was a paramount concern during vehicle development and testing. The fuel for the stage would be clustered into a large octagonal descent stage, which would also provide ground-accessible cargo bays for the mission’s rovers and other surface hardware, along with a wide platform for the other cargo on top of the stage.
For the ascent stage, fuels and engines were again a concern, though from a different perspective. Even the sophisticated new insulation designs being developed for the descent stage would have trouble keeping cryogenic liquid oxygen and, especially, liquid hydrogen fluid through a two-week lunar surface stay, and after a brief study of alternatives both Boeing-Grumman and NASA had concluded that tried and tested hypergols, used in the original Apollo Lunar Module, would have to be used for the new lander’s ascent stage as well. However, since the ascent stage’s fuel was itself cargo for the descent stage and the extended use of the ascent stage as a mission module placed rather firm minimums on its mass, it was critical that the ascent stage achieve the delta-v it needed on as little fuel as possible. To accomplish this, NASA and Boeing had to look outside the United States--where pressure-fed engines were state-of-the-art for hypergolic fuels--to Russia, where brilliant engineers had rejected the American approach of switching to fuel combinations with a superior specific impulse to instead push hypergolic propellants to their uttermost limits. The resulting closed-cycle engines had specific impulses closer to those that might be found in kerosene-liquid oxygen engines, often ten or twenty seconds greater than their American counterparts, yet still used dense and highly storable hypergolic fuels. With an extensive flight history allaying American concern over the relative reliability of pump-fed closed-cycle engines and pressure-fed designs, the S5.92 engine that had originally been designed for the latest generation of Soviet deep-space probes but which had found subsequent use as a mid-performance competitor to the Blok R as an upper stage and as a performance upgrade for smaller rockets was accepted as the ascent stage’s powerplant. Three would be clustered at the stage’s base, allowing the stage to return to L-2 even if one of them failed, whether on the surface or while ascending.
The ascent stage design consisted of a rather squat vertical pressure vessel, with the engines clustered at the bottom and an Apollo drogue port at the top. Fuel would be divided into four tanks, two each of nitrogen tetroxide and UDMH. While slightly heavier than the one tank of each that had been provided for the Apollo LM and given it its distinctive “off-center chipmunk” appearance, Artemis’ higher payload capability meant that trimming every spare ounce of weight wasn’t quite as critical, and the stage balance could be more easily achieved in the four-tank design. A side pressure hatch would provide the entrance into the spacecraft’s airlock module, which would be left behind on top of the descent stage when the spacecraft departed the lunar surface. For safety reasons and to take advantage of a proven system, the life support systems of the ascent stage were subcontracted to the same firm which provided systems for the Rockwell Apollo capsules. Carbon dioxide filter systems and other critical spares aboard the surface habitat, the ascent stage, and the Apollo capsule would be interchangeable--providing protection throughout the mission from the kinds of hassles that had complicated the use of the Apollo LM as a lifeboat during Apollo 13’s flight.
After the lander design reached critical design review in 1995, two years after the awarding of the contract in 1993, work proceeded apace on hardware development and various ground-based testing. Component-level testing of landing gear reactions to the shock of lunar touchdown, breadboard examinations of radar, the construction and programming of the lander’s twin guidance systems, and much more took place throughout 1995 and 1996 while work on the manufacturing of structural demonstrators took place. Finally, in spring 1997, the first structural test vehicles passed initial pressure testing, and integration began on the first complete test vehicles. When these were completed, one was shipped to NASA Glenn’s Plum Brook for full-scale testing in the facility’s massive vacuum chamber, as well as aeroacoustic tests. As these tests began, the next, consisting of a descent stage only, was being finished ahead of its date with space.
The first flight of the Artemis descent stage came in February 1998 under the mission name Artemis 2. Together with a Pegasus third stage, the vehicle was carried into orbit on a Saturn H03, carrying on its deck a functional (though not furnished) surface habitat. Pegasus had completed its own demonstration flight flying partially-filled as a third stage on a Saturn M02 in October 1997, placing the depleted stage into heliocentric orbit. On Artemis 2, as on an operational cargo flight, the Pegasus was fired partially during ascent in order to place itself and the payload into orbit. Though the hardware carried by the launch was essentially the same as the planned final cargo lander delivery stack, there was one key difference.
While cargo flights would launch with their Pegasus departure stage, the heavier crew stack would require a full Pegasus stage for Earth departure, and thus would be too heavy for a single H03--even the uprated IIP H03--to loft. Instead, the Pegasus and the crew stack would have to rendezvous and dock in orbit, which had posed a serious design problem--the development of a docking standard capable of holding the stack together during the departure burn under hundreds of kiloNewtons of compressive force. While this force requirement was far beyond the capacity of the CADS docking ring alone, CADS was capable of handling the initial docking loads. Thus, NASA sought to avoid reinventing the wheel by building on the CADS design. The final docking standard developed, the Large Payload Attachment System (LPAS), would consist of a CADS ring augmented by a second, large-diameter mating ring. The CADS docking ring and petals would serve to guide the lander and crew capsule (as the active vehicle) into a docking with the passive Pegasus. Once docked, the retraction of the CADS rings to effect hard dock would also bring together the outer force-transfer rings, which would be rigidized by a set of electrically-driven bolts. Artemis 2 carried a pre-mated version of this hybrid LPAS system between the descent stage and and Pegasus, instead of the single-piece fixed truss that was intended for operational cargo flights.
Once on orbit, the lander was powered up and its systems checked out and verified as functional. Then, the lander retracted the bolts on the hybrid ring and separated from the Pegasus. Over several days, during which time the temperatures of both hydrogen-fueled stages were monitored, the lander practiced docking to the Pegasus under a variety of lighting conditions, proving that the hybrid system could be relied upon for future crew flights. With the system fully proven, the lander conducted one final docking with the Pegasus, and the Pegasus was fired up to send the lander into a highly elliptical orbit through Earth’s Van Allen belts. With this step completed, the truss attaching the descent stage to its side of the hybrid ring was separated with explosive bolts. Once it was cast loose, Pegasus conducted one final maneuver to lower its perigee to intersect Earth’s atmosphere for disposal. The inflatable “loft” of the surface habitat resting of the descent lander’s deck was deployed, and dosimeters throughout the habitat’s cabin were used to monitor the radiation attenuation at various positions in the cabin, including the loft and the “storm shelter” within the rigid portion of the habitat, confirming that the habitat would be capable of keeping astronauts from excessive radiation doses while on the lunar surface.
Meanwhile, the NASA operations team and Boeing engineers monitored the performance of the lander’s computers and other systems as it carried the habitat through the belts high above the Earth. Just as they were designed, the lander’s computers had little trouble dealing with the radiation-filled environment of the belts--qualifying both the computers of the descent stage and the modified versions which would control the ascent stage. With the proving passes complete, the descent stage fired its engines in space for the first time, lowering Artemis 2’s orbit below the belts. A number of additional burns were conducted, altering the mission’s inclination and consuming delta-v without changing the orbital altitude as NASA confirmed that the lander’s engine would reliably relight and that the lander’s computers could handle the problem of guiding the stage. The surface habitat was monitored, watching the pressure inside the loft for thankfully-absent leaks--NASA’s gamble on inflatables was proving well in its first in-space deployment. Finally, after almost a week in space and almost a dozen firings of the engines, which had shown not a single failure to light, Artemis 2 conducted a final burn that sent it on the same track as the Pegasus stage which had carried it to orbit, speeding low into the Earth’s atmosphere before breaking up in a fiery tail of debris. The first Artemis lander flight had been a complete success.
Due to the use of LC-39’s facilities for Freedom logistics operations and the pace of Bethpage and NASA’s evaluations and tweaks to the lander, it was five months before Artemis 3 would follow in Artemis 2’s path. June 1998 saw the first dual-launch Artemis mission, with an H03 carrying up a crew-configuration lander similarly pre-docked to a Pegasus stage met in orbit by a lunar-configuration Block V Apollo capsule launched aboard a Saturn M02 the same day. The Artemis 3 crew, lead by veteran pilot Jack Bailey (who had also been the first commander of Freedom), consisted of four pilot-trained astronauts, including Chris Valente, an experienced commander in his own right. After several trials duplicating the docking carried out by Artemis 2’s computers, Bailey’s crew fired their Pegasus stage to place themselves on a similar belt-passing trajectory. Unlike the departure burns on Apollo, the Artemis stack would have its crew “eyeballs” out for the trajectory, with Apollo’s nose facing aft. However, because the maximum forces capable of being passed through the Apollo probe and drogue connection limited to the stack were limited for structural reasons to a mere 0.5 G of acceleration, the Artemis 3 crew experienced little overall discomfort.
After the burn was complete and the Pegasus had been cast loose for its date with destruction over the ocean, the Artemis 3 crew opened the hatch between the lander and the capsule, and began to power up the lander’s ascent and descent stages, testing their systems as well. At perigee after the vehicle’s trouble-free pass through the belts, the crew used the descent stage to lower the stack’s orbit below the belts, at which point Bailey transferred to the lander while Valente took control of the Apollo. Without the mass of the ascent stage, the Apollo’s 2.25 tons of return propellant gave it 600 m/s of delta-v while retaining margin for landing, so Bailey’s crew aboard the lander performed a number of burns over the next day to “bounce” its inclination back and forth four degrees above the base 27.5 degree inclination, this being within the inclination change which would allow Valente’s Apollo to come after them should they suffer issues. On their next pass over the equator, they then fired the descent stage again, changing inclination again across 27.5 degrees to four degrees below it (23.5 degrees), and then on another pass returned back to 27.5 degrees to meet back up with the capsule. In total, it was sufficient to demonstrate the delta-v of nearly a full lunar descent, with the four starts and shutdowns being used to qualify the engine’s start response and burn residuals under a varied set of throttle and ignition conditions. The descent stage was then ejected, and placed into a decaying orbit with the last of its fuel, while Bailey repeated the process using the ascent stage’s engines. At the end of the “relay race” Artemis 3 flight, the lander had been tested and qualified as thoroughly as possible, short of actually landing on the moon. While Valente and his co-pilot waited, “hands-off” but ready to take action in case of an emergency, Bailey and his co-pilot practiced the process of docking the ascent stage back to the Apollo capsule, using the ascent stage as the active vehicle--which would be necessary during the return to the quiescent Apollo capsule after an Artemis flight. With this final task completed, the Artemis crew returned to Earth, once more testing the “skip entry” technique for a pinpoint landing of Hawai’i.
The question of the next test flight had been a topic of hot debate within NASA’s management. In the original plans, a separate test flight of the lander ahead of the first manned mission’s cargo lander had been called for (and budgeted). After all, despite their ventures into extreme-altitude orbits, none of the Apollo test missions so far had even approached the lunar sphere of influence. However, a manned landing test would require an additional two Saturn Heavies, and a cost of almost a billion dollars. While an unmanned touchdown of the cargo lander would achieve a similar goal for just half the cost, it would then mean that another half-billion would have to be spent acquiring a second cargo lander, the 14-ton payload of the demonstration lander squandered to no end carrying a mass simulator. However, in 1996, a surface hardware group study had kicked around the idea of taking the chance to test the surface habitat on the lunar surface ahead of its first operational use. After all, the cost of the surface habitat was nothing compared to the cost of the unmanned test landing itself, and would provide a valuable chance to test the habitat once more.
The report’s authors were rather startled to find themselves invited to fly to headquarters to brief none other than Administrator Davis himself, who their memo had apparently reached. Expecting a lecture about unnecessary costs (Davis’ frugality and unwillingness to suffer fools having become infamous within NASA circles), they were instead startled to be interrogated not just about how they’d developed their thoughts, but on the potential costs of simply fitting this test habitat out as a full cargo landing mission--after all, weren’t the final EVA suits and other fittings also rather trivial compared to the total mission cost? And, in this case, if this initial landing worked, the payload left on the lunar surface wouldn’t even be a spare test mission, but the full first landing site, ready for the crew to join it--saving the half billion dollars of the first cargo flight and valuable time off the officially unrecognized but well-understood 30th anniversary deadline. The rest of the Artemis hardware stood largely ready, with the Mesyat network in place, the Apollo Block V already entering servicing to replace the Block IV for Freedom logistics, and the surface hardware teams clearly chomping at the bit to get their first tests on the surface. Far from a reprimand for thinking wastefully, the report’s writers were told to put together a team to study the question, and analyze the savings in comparison to the mission’s odds of success. When the initial Artemis test flights were completed in mid-1998, Lloyd Davis thus came to Boeing-Grumman Bethpage and the Artemis program office with a simple question: were they more than 10% confident the landing would succeed? The combined staff indicated that they were far, far more confident--more like 80% to 90% sure. This dramatically exceeded the “magic number” that Davis’ informal research had suggested as a minimum break-even point, and thus Davis made his decision, the so-called “banker’s bet”--the next Artemis lander flight would be delayed from the scheduled September flight to the other side of the October Freedom crew rotation, into November. However, Artemis 4 would be going to the moon not as a simple test, but as the first cargo landing of the Artemis manned flights--simultaneously a test and an operational flight. If it succeeded, the manned landing could follow as the next flight. If it failed, then it would have served its function as a test. With all the components ready and a bet on success, the countdown was on to the return to the moon.
Anyway, without further teasing, let's be about it...Eyes Turns Skyward, Part III: Post #18
By the mid-1990s, Boeing’s position in the space industry had grown to one that other companies, be they existing competitors or new upstarts, were well justified in being envious of. With an effective state-sponsored monopoly in large launchers due to ongoing NASA and DoD support for the Saturn Multibody family, and the approaching promise of Artemis flights on the Heavy variant of the booster, Boeing was in the attracting position of having guaranteed and stable profits in its space division, even before it had clinched the Artemis lander contract with the purchase of Grumman and its acquisition of that company’s talent and experience.
Even the most stable monopoly brings its own challenges, however, and in this respect Boeing’s position was perhaps not quite as desirable as entrepreneurs competing with the emerging Internet boom for venture capital might have wanted to believe. With the Saturn Multibody uncompetitive in the commercial market due to excessive size and relatively high per-launch costs, Boeing-Grumman possessed no entrant in the rapidly growing and, as Lockheed was showing, profitable commercial market. Reliable and reasonably cost-effective for large governmental payloads like Freedom resupply and rotation missions or military spy satellites, even the smallest Saturn variant faced the same problem as Vulkan in competing for commercial dollars, being too large for even the largest commercial satellites. Moreover, unlike the cash-strapped Russian program, to whom selling commercial Vulkan was very nearly a matter of life or death, Boeing’s guaranteed governmental contracts ensured that Saturn would always have a nice, stable cash flow, with a virtual floor of nine flights per year, shooting up to ten or eleven in some years. With Artemis, requiring a further nine cores per year, looming on the horizon, there was even less pressure for Boeing to try to compete; even if they wanted to, their manufacturing operations at Michoud would be near their limit at 18 cores per year, and for all but the most lucrative and long-term contracts the expense of expanding their operations would outweigh the revenue possible from more flights.
Under these conditions, Boeing’s management was largely content to let the space division run itself, choosing instead to focus attention on the highly competitive airliner market, where they were facing severe pressure from Airbus, Lockheed, and McDonnell Douglas, on one side, and smaller firms like Bombardier on the other, or the upcoming Joint Strike Fighter contract, possibly worth a trillion dollars or even more over the next several decades. Indeed, their purchase of Grumman had been largely intended to improve their positioning for this competition, whose winner would likely dominate American tactical fighter production--and therefore export markets for American fighter aircraft--for decades to come. Compared to the serious competition they were facing in both sectors, the stable, profitable, and safe space market seemed worthy of little focus from the greater corporate entity.
To their customers, of course, Multibody was an important part of their space operations, and whatever shortfalls in attention Saturn might have suffered from Boeing, it certainly lacked none from NASA and the Air Force, especially as Artemis continued to advance as a program. In order to achieve the best possible performance from the Saturn Heavy in its role as the critical Artemis launch vehicle, Boeing was tasked by NASA with performing its own version of the “interim improvements” already undertaken by McDonnell on the Delta 4000 family. Compared to the massive overhaul given to Delta, though, Saturn’s facelift was minor, mainly focusing on production streamlining, the introduction of improved models of the J-2 second stage engine, and the replacement of the aluminum skin of the S-IVB and C upper stages with lighter-weight aluminum-lithium alloys. Altogether, it was enough to push the payload of the Saturn H03 to over 80 tons, increases eagerly put to work by Artemis’ mission designers.
Of course, one of the design bureaus benefiting most from the changes was Boeing-Grumman’s own Bethpage spaceflight division, inherited from Grumman, which retained its responsibility for the design of the Artemis lunar lander. The task of the lander design was complicated by the fact that, like the original Apollo lander, it was really not one but two spacecraft: the descent stage and the ascent stage. Even compared to the Lunar Module, however, the new design would require an unusual amount of independence between its two parts, driven by the fact that the two stages had their own crucial and separate missions. Unlike Apollo’s descent stage, Artemis’ would also be used independently for cargo flights, and therefore require its own attitude control, gyroscopes, radar, and computer systems to allow it to land autonomously on the surface of the moon at sites precisely selected from orbital imagery that the international flotilla of precursor probes would provide. Meanwhile, the ascent stage would have a crucial life-support role through all the stages of the flight, serving not only as the sole transport vehicle for the journey to and from the Moon to L-2, but also as a key extension of the living space available within the Apollo itself on the voyage to and from the Earth. Both stages would also need to be much more capable as rockets than the original Apollo LM, in order to travel all the way to and from the Apollo capsule waiting patiently at L-2.
Additional challenges came with the fuels required for the trip. While Bethpage had recent experience with hydrogen-fueled landers, the need to store cryogenic fluids for the entire coast to the moon was a new challenge, requiring the solution of new problems in insulation and thermal management to ensure adequate supplies of these fuels throughout the mission. With the higher specific impulse of the new RL-10-A4 engines being key to the mission design, however, these problems had to be solved if Artemis was to succeed; and lurking in the back of the mind were always the similar but far greater challenges posed by Mars missions, even if NASA was not officially pursuing the Red Planet. Three of these engines would be fitted in a line on the bottom of the descent stage, with all three used for the powered descent initiation (PDI) burn which would slow down the lander, bringing it out of its trajectory from Earth or L-2 and setting it on course down to the surface. However, for the final part of the descent to touchdown, firing all three engines would require excessively high throttle ratios, so the plan was to proceed to touchdown only on the center engine or (if that engine failed to restart) on the paired outer engines. Despite this theoretical redundancy, ensuring that restart would be reliable and guaranteed was a paramount concern during vehicle development and testing. The fuel for the stage would be clustered into a large octagonal descent stage, which would also provide ground-accessible cargo bays for the mission’s rovers and other surface hardware, along with a wide platform for the other cargo on top of the stage.
For the ascent stage, fuels and engines were again a concern, though from a different perspective. Even the sophisticated new insulation designs being developed for the descent stage would have trouble keeping cryogenic liquid oxygen and, especially, liquid hydrogen fluid through a two-week lunar surface stay, and after a brief study of alternatives both Boeing-Grumman and NASA had concluded that tried and tested hypergols, used in the original Apollo Lunar Module, would have to be used for the new lander’s ascent stage as well. However, since the ascent stage’s fuel was itself cargo for the descent stage and the extended use of the ascent stage as a mission module placed rather firm minimums on its mass, it was critical that the ascent stage achieve the delta-v it needed on as little fuel as possible. To accomplish this, NASA and Boeing had to look outside the United States--where pressure-fed engines were state-of-the-art for hypergolic fuels--to Russia, where brilliant engineers had rejected the American approach of switching to fuel combinations with a superior specific impulse to instead push hypergolic propellants to their uttermost limits. The resulting closed-cycle engines had specific impulses closer to those that might be found in kerosene-liquid oxygen engines, often ten or twenty seconds greater than their American counterparts, yet still used dense and highly storable hypergolic fuels. With an extensive flight history allaying American concern over the relative reliability of pump-fed closed-cycle engines and pressure-fed designs, the S5.92 engine that had originally been designed for the latest generation of Soviet deep-space probes but which had found subsequent use as a mid-performance competitor to the Blok R as an upper stage and as a performance upgrade for smaller rockets was accepted as the ascent stage’s powerplant. Three would be clustered at the stage’s base, allowing the stage to return to L-2 even if one of them failed, whether on the surface or while ascending.
The ascent stage design consisted of a rather squat vertical pressure vessel, with the engines clustered at the bottom and an Apollo drogue port at the top. Fuel would be divided into four tanks, two each of nitrogen tetroxide and UDMH. While slightly heavier than the one tank of each that had been provided for the Apollo LM and given it its distinctive “off-center chipmunk” appearance, Artemis’ higher payload capability meant that trimming every spare ounce of weight wasn’t quite as critical, and the stage balance could be more easily achieved in the four-tank design. A side pressure hatch would provide the entrance into the spacecraft’s airlock module, which would be left behind on top of the descent stage when the spacecraft departed the lunar surface. For safety reasons and to take advantage of a proven system, the life support systems of the ascent stage were subcontracted to the same firm which provided systems for the Rockwell Apollo capsules. Carbon dioxide filter systems and other critical spares aboard the surface habitat, the ascent stage, and the Apollo capsule would be interchangeable--providing protection throughout the mission from the kinds of hassles that had complicated the use of the Apollo LM as a lifeboat during Apollo 13’s flight.
After the lander design reached critical design review in 1995, two years after the awarding of the contract in 1993, work proceeded apace on hardware development and various ground-based testing. Component-level testing of landing gear reactions to the shock of lunar touchdown, breadboard examinations of radar, the construction and programming of the lander’s twin guidance systems, and much more took place throughout 1995 and 1996 while work on the manufacturing of structural demonstrators took place. Finally, in spring 1997, the first structural test vehicles passed initial pressure testing, and integration began on the first complete test vehicles. When these were completed, one was shipped to NASA Glenn’s Plum Brook for full-scale testing in the facility’s massive vacuum chamber, as well as aeroacoustic tests. As these tests began, the next, consisting of a descent stage only, was being finished ahead of its date with space.
The first flight of the Artemis descent stage came in February 1998 under the mission name Artemis 2. Together with a Pegasus third stage, the vehicle was carried into orbit on a Saturn H03, carrying on its deck a functional (though not furnished) surface habitat. Pegasus had completed its own demonstration flight flying partially-filled as a third stage on a Saturn M02 in October 1997, placing the depleted stage into heliocentric orbit. On Artemis 2, as on an operational cargo flight, the Pegasus was fired partially during ascent in order to place itself and the payload into orbit. Though the hardware carried by the launch was essentially the same as the planned final cargo lander delivery stack, there was one key difference.
While cargo flights would launch with their Pegasus departure stage, the heavier crew stack would require a full Pegasus stage for Earth departure, and thus would be too heavy for a single H03--even the uprated IIP H03--to loft. Instead, the Pegasus and the crew stack would have to rendezvous and dock in orbit, which had posed a serious design problem--the development of a docking standard capable of holding the stack together during the departure burn under hundreds of kiloNewtons of compressive force. While this force requirement was far beyond the capacity of the CADS docking ring alone, CADS was capable of handling the initial docking loads. Thus, NASA sought to avoid reinventing the wheel by building on the CADS design. The final docking standard developed, the Large Payload Attachment System (LPAS), would consist of a CADS ring augmented by a second, large-diameter mating ring. The CADS docking ring and petals would serve to guide the lander and crew capsule (as the active vehicle) into a docking with the passive Pegasus. Once docked, the retraction of the CADS rings to effect hard dock would also bring together the outer force-transfer rings, which would be rigidized by a set of electrically-driven bolts. Artemis 2 carried a pre-mated version of this hybrid LPAS system between the descent stage and and Pegasus, instead of the single-piece fixed truss that was intended for operational cargo flights.
Once on orbit, the lander was powered up and its systems checked out and verified as functional. Then, the lander retracted the bolts on the hybrid ring and separated from the Pegasus. Over several days, during which time the temperatures of both hydrogen-fueled stages were monitored, the lander practiced docking to the Pegasus under a variety of lighting conditions, proving that the hybrid system could be relied upon for future crew flights. With the system fully proven, the lander conducted one final docking with the Pegasus, and the Pegasus was fired up to send the lander into a highly elliptical orbit through Earth’s Van Allen belts. With this step completed, the truss attaching the descent stage to its side of the hybrid ring was separated with explosive bolts. Once it was cast loose, Pegasus conducted one final maneuver to lower its perigee to intersect Earth’s atmosphere for disposal. The inflatable “loft” of the surface habitat resting of the descent lander’s deck was deployed, and dosimeters throughout the habitat’s cabin were used to monitor the radiation attenuation at various positions in the cabin, including the loft and the “storm shelter” within the rigid portion of the habitat, confirming that the habitat would be capable of keeping astronauts from excessive radiation doses while on the lunar surface.
Meanwhile, the NASA operations team and Boeing engineers monitored the performance of the lander’s computers and other systems as it carried the habitat through the belts high above the Earth. Just as they were designed, the lander’s computers had little trouble dealing with the radiation-filled environment of the belts--qualifying both the computers of the descent stage and the modified versions which would control the ascent stage. With the proving passes complete, the descent stage fired its engines in space for the first time, lowering Artemis 2’s orbit below the belts. A number of additional burns were conducted, altering the mission’s inclination and consuming delta-v without changing the orbital altitude as NASA confirmed that the lander’s engine would reliably relight and that the lander’s computers could handle the problem of guiding the stage. The surface habitat was monitored, watching the pressure inside the loft for thankfully-absent leaks--NASA’s gamble on inflatables was proving well in its first in-space deployment. Finally, after almost a week in space and almost a dozen firings of the engines, which had shown not a single failure to light, Artemis 2 conducted a final burn that sent it on the same track as the Pegasus stage which had carried it to orbit, speeding low into the Earth’s atmosphere before breaking up in a fiery tail of debris. The first Artemis lander flight had been a complete success.
Due to the use of LC-39’s facilities for Freedom logistics operations and the pace of Bethpage and NASA’s evaluations and tweaks to the lander, it was five months before Artemis 3 would follow in Artemis 2’s path. June 1998 saw the first dual-launch Artemis mission, with an H03 carrying up a crew-configuration lander similarly pre-docked to a Pegasus stage met in orbit by a lunar-configuration Block V Apollo capsule launched aboard a Saturn M02 the same day. The Artemis 3 crew, lead by veteran pilot Jack Bailey (who had also been the first commander of Freedom), consisted of four pilot-trained astronauts, including Chris Valente, an experienced commander in his own right. After several trials duplicating the docking carried out by Artemis 2’s computers, Bailey’s crew fired their Pegasus stage to place themselves on a similar belt-passing trajectory. Unlike the departure burns on Apollo, the Artemis stack would have its crew “eyeballs” out for the trajectory, with Apollo’s nose facing aft. However, because the maximum forces capable of being passed through the Apollo probe and drogue connection limited to the stack were limited for structural reasons to a mere 0.5 G of acceleration, the Artemis 3 crew experienced little overall discomfort.
After the burn was complete and the Pegasus had been cast loose for its date with destruction over the ocean, the Artemis 3 crew opened the hatch between the lander and the capsule, and began to power up the lander’s ascent and descent stages, testing their systems as well. At perigee after the vehicle’s trouble-free pass through the belts, the crew used the descent stage to lower the stack’s orbit below the belts, at which point Bailey transferred to the lander while Valente took control of the Apollo. Without the mass of the ascent stage, the Apollo’s 2.25 tons of return propellant gave it 600 m/s of delta-v while retaining margin for landing, so Bailey’s crew aboard the lander performed a number of burns over the next day to “bounce” its inclination back and forth four degrees above the base 27.5 degree inclination, this being within the inclination change which would allow Valente’s Apollo to come after them should they suffer issues. On their next pass over the equator, they then fired the descent stage again, changing inclination again across 27.5 degrees to four degrees below it (23.5 degrees), and then on another pass returned back to 27.5 degrees to meet back up with the capsule. In total, it was sufficient to demonstrate the delta-v of nearly a full lunar descent, with the four starts and shutdowns being used to qualify the engine’s start response and burn residuals under a varied set of throttle and ignition conditions. The descent stage was then ejected, and placed into a decaying orbit with the last of its fuel, while Bailey repeated the process using the ascent stage’s engines. At the end of the “relay race” Artemis 3 flight, the lander had been tested and qualified as thoroughly as possible, short of actually landing on the moon. While Valente and his co-pilot waited, “hands-off” but ready to take action in case of an emergency, Bailey and his co-pilot practiced the process of docking the ascent stage back to the Apollo capsule, using the ascent stage as the active vehicle--which would be necessary during the return to the quiescent Apollo capsule after an Artemis flight. With this final task completed, the Artemis crew returned to Earth, once more testing the “skip entry” technique for a pinpoint landing of Hawai’i.
The question of the next test flight had been a topic of hot debate within NASA’s management. In the original plans, a separate test flight of the lander ahead of the first manned mission’s cargo lander had been called for (and budgeted). After all, despite their ventures into extreme-altitude orbits, none of the Apollo test missions so far had even approached the lunar sphere of influence. However, a manned landing test would require an additional two Saturn Heavies, and a cost of almost a billion dollars. While an unmanned touchdown of the cargo lander would achieve a similar goal for just half the cost, it would then mean that another half-billion would have to be spent acquiring a second cargo lander, the 14-ton payload of the demonstration lander squandered to no end carrying a mass simulator. However, in 1996, a surface hardware group study had kicked around the idea of taking the chance to test the surface habitat on the lunar surface ahead of its first operational use. After all, the cost of the surface habitat was nothing compared to the cost of the unmanned test landing itself, and would provide a valuable chance to test the habitat once more.
The report’s authors were rather startled to find themselves invited to fly to headquarters to brief none other than Administrator Davis himself, who their memo had apparently reached. Expecting a lecture about unnecessary costs (Davis’ frugality and unwillingness to suffer fools having become infamous within NASA circles), they were instead startled to be interrogated not just about how they’d developed their thoughts, but on the potential costs of simply fitting this test habitat out as a full cargo landing mission--after all, weren’t the final EVA suits and other fittings also rather trivial compared to the total mission cost? And, in this case, if this initial landing worked, the payload left on the lunar surface wouldn’t even be a spare test mission, but the full first landing site, ready for the crew to join it--saving the half billion dollars of the first cargo flight and valuable time off the officially unrecognized but well-understood 30th anniversary deadline. The rest of the Artemis hardware stood largely ready, with the Mesyat network in place, the Apollo Block V already entering servicing to replace the Block IV for Freedom logistics, and the surface hardware teams clearly chomping at the bit to get their first tests on the surface. Far from a reprimand for thinking wastefully, the report’s writers were told to put together a team to study the question, and analyze the savings in comparison to the mission’s odds of success. When the initial Artemis test flights were completed in mid-1998, Lloyd Davis thus came to Boeing-Grumman Bethpage and the Artemis program office with a simple question: were they more than 10% confident the landing would succeed? The combined staff indicated that they were far, far more confident--more like 80% to 90% sure. This dramatically exceeded the “magic number” that Davis’ informal research had suggested as a minimum break-even point, and thus Davis made his decision, the so-called “banker’s bet”--the next Artemis lander flight would be delayed from the scheduled September flight to the other side of the October Freedom crew rotation, into November. However, Artemis 4 would be going to the moon not as a simple test, but as the first cargo landing of the Artemis manned flights--simultaneously a test and an operational flight. If it succeeded, the manned landing could follow as the next flight. If it failed, then it would have served its function as a test. With all the components ready and a bet on success, the countdown was on to the return to the moon.
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So if I read it right, again NASA has had to turn to their Russian Counterparts to get an essential piece of equipment that was up to the job. Okay, so 1,960 N of thrust doesn't sound very impressive, but the Lunar Surface Gravity is only about 16.7% that of Earth's, so you don't need as powerful an engine to get off its surface. But did I read the S5.92 as being a Gas-Generator Cycle Engine? Still, 327s of Isp should be enough provided the propellant load is sufficient.
Have to say, I like the simple fact that they're making certain parts the same for both the Apollo Block V and the Artemis Ascent Stage, so that's one area of concern nicely dealt with, though it goes without saying that they'll be making sure that it won't need to be done - but it always helps to be ready for such things.
Of course, with this much info about the testing phase of Artemis, you have pretty much given away what the next post will involve.
Have to say, I like the simple fact that they're making certain parts the same for both the Apollo Block V and the Artemis Ascent Stage, so that's one area of concern nicely dealt with, though it goes without saying that they'll be making sure that it won't need to be done - but it always helps to be ready for such things.
Of course, with this much info about the testing phase of Artemis, you have pretty much given away what the next post will involve.
You caught me. It's an onomatopoeic rendition of Swedish flute music to illustrate the effects on culture.Of course, with this much info about the testing phase of Artemis, you have pretty much given away what the next post will involve.
19.6 kN, not 1.96 kN. It makes a difference.
Yep, it's enough. Ironically, the payload mass landed by the Lunar Crew Module (if you include the Ascent Stage) is greater than the payload mass landed by the Lunar Cargo Module, since the latter can only be partially-fueled if it's to fit on the H03 with its Pegasus. If a Pegasus could meet with a fully-fueled descent stage, I calculate just short of 24 tons of cargo to the lunar surface, but that's sadly less cost-effective in our calculations than this mission. If only there was some way to get a fully loaded Pegasus and a fully-fueled descent stage into orbit using only one flight of Multibody H03. A matter worth depositing some thoughts into indeed, see what that might fuel....
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Fantastic update, e of pi.
Davis's "banker's bet" isn't as ballsy as Webb's decision to go with all-up testing on Saturn V, but still quite bold, especially for the late 90's.
Davis's "banker's bet" isn't as ballsy as Webb's decision to go with all-up testing on Saturn V, but still quite bold, especially for the late 90's.
19.6 kN, not 1.96 kN. It makes a difference.
Whoops! Misread it!
Only two ways that I can see that happening are with:
- Closed-Cycle Engines to replace the Open-Cycle ones they're using right now; and/or
- More CCBs; and/or
- Bigger Stages (especially the EDS)
The all-up test had one small thing in its favour. They had already ground-tested all the parts prior to that first flight. And while they didn't have all the bugs worked out, they were able to resolve them (for the most part) by the time they were ready to put Borman, Lovell, and Anders in one.
Which is a lot better than the Soviet N1, which was all-up tested without ground-testing of all the parts.
Freedom is not getting shut down, so I'd assume so.
But that's probably also a big reason why NASA can only afford one sortie to the Moon per year. The budgeting will get more interesting when NASA tries to take the next step to a man-tended (if not permanently manned) permanent lunar base after the initial batch of Artemis missions are completed. But at some point in the late 00's, I assume we're looking at a wind-down on Freedom, which will be approaching the end of its planned life expectancy. Then, at that point, a good deal more operational budget gets freed up.
P.S. I can't wait to see what kind of renders Nixonshead has hacked up for us on Monday. We're all counting on you, NH.
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Which of course was not unrelated to the N1's disastrous testing record.
Still Webb's decision was and is rightly seen as a bold one, one undertaken mainly to meet the 1969 deadline. It worked out, but it gave some folks in Huntsville ulcers at the time.
This decision is less risky, since even if Artemis 4 fails, NASA is only out a cargo lander and a half billion (if I read this rightly), and it can just try again.
And here's a sneak preview
All of Earth will be riveted on seeing the first footage from the Moon when Artemis makes some exciting discoveries missed by the Apollo missions:
All of Earth will be riveted on seeing the first footage from the Moon when Artemis makes some exciting discoveries missed by the Apollo missions:
All of Earth will be riveted on seeing the first footage from the Moon when Artemis makes some exciting discoveries missed by the Apollo missions:
Especially if they bring a Japanese HD Camera with them. No grainy B/W 10fps.
One last thought before the weekend starts:
Which got me to thinking about contingencies for LCM/AS failures...
Obviously, it was never really in the cards that the Cargo Module would be a means of a backup escape capability, just as it would not have been for the equivalent cargo modules on LESA or ALSS. But the lack of any fall-back capability was never something NASA planners were entirely happy with, which is why they played around with Lunar Escape Systems. These would simply use fuel from the ascent module fuel tanks.
Of course, there was never any chance of squeezing LES options on even J class missions, given weight constraints; the idea was that they might be incorporated into longer duration Apollo Applications lunar missions, where there'd be more payload capability to play with (and greater risk from systems dormancy/idleness).
So I'm wondering if NASA has given any thought to any such escape systems for Artemis. Granted, rendezvous with a CSM at L-2 is a different kettle of fish from rendezvous in low lunar orbit, unless the CSM retains sufficient fuel reserve to go into (and then leave) low lunar orbit. If the authors included such considerations in past posts, I must have missed it. But the question was surely explored, at least in cursory fashion, given that NASA has a lot more payload to play with than in the early 70's.
My guess is it was looked at, and set aside. (Also, you have to lift four astronauts, not two.) But I'd also guess that, like NASA's long-term planning for the 70's, it's something that would be looked at for longer-term missions and permanent bases.
Which got me to thinking about contingencies for LCM/AS failures...
Obviously, it was never really in the cards that the Cargo Module would be a means of a backup escape capability, just as it would not have been for the equivalent cargo modules on LESA or ALSS. But the lack of any fall-back capability was never something NASA planners were entirely happy with, which is why they played around with Lunar Escape Systems. These would simply use fuel from the ascent module fuel tanks.
Of course, there was never any chance of squeezing LES options on even J class missions, given weight constraints; the idea was that they might be incorporated into longer duration Apollo Applications lunar missions, where there'd be more payload capability to play with (and greater risk from systems dormancy/idleness).
So I'm wondering if NASA has given any thought to any such escape systems for Artemis. Granted, rendezvous with a CSM at L-2 is a different kettle of fish from rendezvous in low lunar orbit, unless the CSM retains sufficient fuel reserve to go into (and then leave) low lunar orbit. If the authors included such considerations in past posts, I must have missed it. But the question was surely explored, at least in cursory fashion, given that NASA has a lot more payload to play with than in the early 70's.
My guess is it was looked at, and set aside. (Also, you have to lift four astronauts, not two.) But I'd also guess that, like NASA's long-term planning for the 70's, it's something that would be looked at for longer-term missions and permanent bases.
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Very interesting update, but it needs editing. Badly. It looks like two versions smashed together.
Example 1:
paragraph 1, sentence 1:
paragraph 2, sentence 2:
Example 1:
paragraph 1, sentence 1:
paragraph 4, sentence 1:
Example 2:
paragraph 2, sentence 2:
paragraph 5, sentence 1:
There are a few more similiar happenstances in the text. It's a bit distracting.
Workable Goblin and I use gDocs to make changes to each other's posts. In this case, those are a couple sections Goblin overhauled. For some reason, it looks like when I copied out of the doc, it re-inserted my original text alongside Goblin's revised sections. Thanks for the catch, and it will be corrected.
EDIT: And revised.
Congress Renames NASA Flight Center After Neil Armstrong - See more at: http://www.space.com/24236-neil-armstrong-nasa-flight-center-name.html#sthash.N5AeK6CW.dpuf
Good thing those were caught but I still see 2 issues:
The title itself--"Eyes Turns Skyward..."?
The paragraph starting "During the Cold War, Russian engineers had similarly wrestled..." seems to be an alternate rendering of the latter part of the paragraph before. The two need to be merged.
But textual glitches are not your problem alone!
The image link you provided there refuses to load on my browser--not a bad link but a forbidden one, apparently. What was it a picture of?
No matter what, no amount of money spent can guarantee safe return of any crew.
Given the mission profile chosen for Artemis, I'd think the most cost-effective backup would be to design a spartan, highly durable Emergency Rescue Lander/Ascender to be parked at one of the Lagrange points--say, park it at L-1 instead of L-2 to avoid cluttering up the latter.
In the event of an Ascent Module failure that would leave the crew of a mission stranded, the Emergency vehicle would move out of its parking place to land in walking distance of the mission site. In order to allow it to have the delta-V to get it down there with storable hypergolic fuels the other masses involved will have to be ruthlessly trimmed--it would be a crowded, smaller habitable volume with the lowest possible mass of supplies needed to get the four-member crew back to their CSM. No room for moon rock samples or the like, unfortunately! (But those might be retrieved by a later mission or by a later program, decades later perhaps). Once the four have boarded the ascent stage it immediately blasts off to return to the CSM.
Other than the space sled approaches of the LESS (where the idea was not only to come up with a minimal system as light as possible, but indeed to make it entirely out of LEM parts repurposed, much as the Apollo 13 crew had to improvise both adapters for their CO2 scrubbers and power links to let the LEM power the CM--a.k.a. "Ikea instructions from Hell!
) any other approach would involve sending along extra mass each mission that, God willing, would prove to be a complete waste.So that's two approaches I can think of--one, design parts of the LEM to be easily repurposed by spacesuited astronauts with wrenches into a space sled, which would unfortunately have to have the four of them surviving in pressure suits all the way back to L2, over a period of days--
--or have a whole standby LEM parked ready to go--the crew have to wait many days for it to come, and then ride many days back to L2 in a cramped, ultralight version of the ascent module that has been parked for years, maybe the better part of a decade--the food stored aboard would also of course need an infinite shelf life. This alternative requires at least one extra Saturn Heavy launch to place it, if indeed a single such launch can throw a craft heavy enough to get the job done using only storable fuels.Frankly I'd think that any scenario where more than one of the three Ascent stage engines is known to be no-go in advance of the launch would be no more likely than one where either two engines are out but this is not known before launch--in which case the craft is doomed to crash once launched on only one engine, unless the crew is skillful enough to soft-land a capsule not meant for such handling shortly after they've launched--or where one or more engines fail catastrophically, or some other system does, blowing the capsule up and killing the four of them right there. If things are going to go wrong, how sure are they to know in advance? A rescue craft may be covering only a small part of the scenarios where the main vehicles fail--and in most of them, the crew is doomed anyway.
Still I agree providing some alternative way of getting back to the CSM seems only sensible and necessary. Having one standby lander strikes me as a way of doing it without doubling the cost of every mission. Some kind of LESS contingency, allowing crew to jerry-rig a minimal ascent rig, perhaps with an inflatable habitation volume, might also not be very costly and worth something.
I wonder if it would not be too costly to even design the ascent stage to be able to make an emergency landing, as near as possible to the mission base area, if upon ascent not just one but 2 engines fail. One really does not want to crash-land with a load of hypergolic fuel!
But the crashlanding mode would only be needed briefly--if upon takeoff all three, or even only two, engines are working OK and the failures bringing it down to one happen late enough after ascent starts, just one engine would be sufficient to return to L-2 late in the burn.Backup for a descent engine failure would be, as per Apollo, aborting the landing by launching the ascent stage. I believe there might be phases of the descent where that is not going to work, but perhaps, with a fuel supply meant to get all the way back to L-2, even in the worst case the craft can at least get to orbit and then a pre-positioned emergency rescue vehicle can come down and rendezvous, either for the crew to transfer to or in a better case to give the ascent module a nudge back to L-2.
Hello everyone, and welcome to your Monday peek across the inter-dimensional barrier into the world of Eyes. Project Artemis is gathering steam for a human return to the Moon, so let's take a look at some of the machines that will get them there.
Before risking a trip to space, it's important to test as much as you can on the ground. For that, you need a very large thermos...
Before risking a trip to space, it's important to test as much as you can on the ground. For that, you need a very large thermos...