WI: Challenger had made it?

On January 28th, 1986 the Challenger disaster occurred. What if the Aluminum Slag that kept Challenger alive for the first 78 seconds had lasted 62 more seconds?

What would happen if NASA had discovered how close shuttle had come to disaster? Would the public be furious if a whistleblower revealed that the first civilian in space had nearly been killed by rushing?

Or could it make the disaster worse?
 

Archibald

Banned
Nothing would have happened and another shuttle would have blown up sooner rather than later - I bet you 100%, before the end of 1987. The shuttle launch agenda was gruesome and unsustainable, a train wreck.

A striking example is what was planned for May 1986. Two planetary probes, Galileo and Ulysses, were to be launched to Jupiter on the same launch window (Ulysses needed Jupiter to launch itself toward the Sun) - only some days apart. Both probes needed a very dangerous Centaur ticking bomb in the payload bay.

By the way, a shuttle mission launched on January 24, 1985 in horrible weather and major O-ring erosion was found. NASA just shrugged and charged ahead. The root cause was that back in '72 they had promised 60 launches a year then in 1981 had downrated launch rate to 24 a year. That was the unflexible treshold they couldn't give up. It was 24 launches in 1987 or burst. Well, Challenger burst.

Even the mission before Challenger - Columbia STS-61A - dodged two bullets by pure luck.

There were all kind of evils lurking in the shuttle guts, ready to kill a crew.
 
How about a SUPER close call:
The explosion happens, but, through some near miracle, the shuttle comes out of the explosion, and manages to land back at Kennedy Space Center. As people are talking about Apollo 13 redux, they're also saying, "Fix this!"
Is there any possible explosion that has the shuttle managing to land semi intact?
 
How about a SUPER close call:
The explosion happens, but, through some near miracle, the shuttle comes out of the explosion, and manages to land back at Kennedy Space Center. As people are talking about Apollo 13 redux, they're also saying, "Fix this!"
Is there any possible explosion that has the shuttle managing to land semi intact?


At the time of the Challenger disaster, there wasn't any way for a shuttle or the crew to survive an incident where all 3 main engines were lost, (or ran out of fuel due to the external tank exploding) even if the orbiter itself was somehow still completely intact. (https://en.wikipedia.org/wiki/File:ShuttleAbortPre51L.png)

Challenger might be able to survive if the o-ring failed on a different side of the SRB, so the exhaust coming out the side wasn't blasting the external tank and the strut holding it in place, though there would still be the unbalanced SRB thrust to deal with. (The SRB survived the breakup until burnout/the self destruct signal was sent, despite the damage from the o-ring failure)


Could Challenger, thus damaged, survive reentry? Or would she end up like Columbia?

If the slag held, there shouldn't be any damage to the orbiter itself, so it should be able to survive reentry without any problems.
 
To summarize==

1) no explosion at all, the slag holds=> another blowup somewhat later, but not too much later.
2) O-ring fails but on the far side from the tank--bad boost, thrust imbalanced, no way to abort anything=> possible mission continuation depending on how badly off the boost phase is, possible once-around abort, possible abort to African landing field, possible crash in the Atlantic which the Shuttle could not do survivably, so everyone would have to improvise jumping out of the gliding orbiter on parachutes, which I presume were handy, and with life rafts which I hope were handy. If the aerodynamics of the Orbiter in glide mode even allowed for crew to bail out. They'd have to do it one by one and be scattered miles apart on the open ocean.
No matter what, with or without loss of crew, the mission will be badly impacted and attention focused on the problem.

With loss of life avoided, the atmosphere will be less somber, but it will be necessary for NASA to adopt the new version of booster, meaning a hiatus in launches until the new design is finalized, ordered, and produced; it probably requires a campaign of firing tests too.

It could be worse than OTL, I guess, the O-Ring could fail within seconds of booster ignition causing the tank explosion while the Shuttle is still on the pad, wrecking the pad. In this circumstance, the blast from the tank explosion would impact the Orbiter worse, due to happening at low altitude, in denser air with lower, very subsonic airspeed. I don't know if it is known absolutely whether the crew was killed instantly when the blast wave from the tank hit them, or if they died later, of injuries during descent or with the final impact on the sea.

If they were known to survive for a while after the explosion I'd say they might have a chance with a pad explosion, but the blast being relatively more powerful, probably not. If they were known to be dead with the blast OTL, surely this surface blast will kill them too. If they could survive the initial blast, presumably the Orbiter would fly off like a kicked football, very likely breaking up, and if not, it will land going crunch somewhere, on land I think most likely because I think the Orbiter faced inward from the shore. That crash landing seems likely to finish the job of killing any crew left alive by the blast and spin.

No telling what the Orbiter would crash onto. What if it hits the VAB?

Meanwhile the tank going boom on the ground is likely to kill some more people I'd think--unless observer zones were set up with a most pessimistic estimate of possible blast energies, which they ought to have been.

So best case scenario, on this launch or an earlier one, an O-ring failure that produces a spectacular gusher of fire squirting sideways away from the fuel tank causes a degraded mission as the Orbiter reaches orbit but falls short of mission target. NASA cannot shrug it off, especially when people realize what would have happened if the torch had been pointed inward and that there is no particular reason it shouldn't have been. All launches go on hold while the new booster design is ordered and procured.

But with Challenger surviving, there is never any authorization to construct Endeavor. As the fleet nears EOL, there is no young, ultralight version in the inventory.
 
The on-paper turn around time for the space shuttle was 17 days. In theory that meant the space shuttle was supposed to launch a couple of times a month. Prior to the Challenger accident, it was a relatively common, and no doubt impressive sight, for NASA to have two shuttles prepping on the pad at the same time, but in order for that to happen NASA had to cut a lot of corners. Challenger taught them that the space shuttle had been way over-engineered. After Challenger having two shuttles on the pad at the same time became very, very rare.
 
To summarize==

1) no explosion at all, the slag holds=> another blowup somewhat later, but not too much later.

This assumes that whatever incident does happen still isn't enough to warrant the redesign that resulted in the switch from SSSRBs to RSRMs. The most severe incident that could happen while ensuring Challenger's survival would've been having a more minor O-ring blow-through later in the SSSRB burn. This would still be the most severe O-ring erosion incident in the program's history and would inevitably result in a flight stoppage and incident review, although the Rogers Commission that happened in OTL would not have happened.

2) O-ring fails but on the far side from the tank--bad boost, thrust imbalanced, no way to abort anything=> possible mission continuation depending on how badly off the boost phase is, possible once-around abort, possible abort to African landing field, possible crash in the Atlantic which the Shuttle could not do survivably, so everyone would have to improvise jumping out of the gliding orbiter on parachutes, which I presume were handy, and with life rafts which I hope were handy. If the aerodynamics of the Orbiter in glide mode even allowed for crew to bail out. They'd have to do it one by one and be scattered miles apart on the open ocean.
No matter what, with or without loss of crew, the mission will be badly impacted and attention focused on the problem.

This would've been an LOM/LOV (loss of mission/loss of crew) incident and would've resulted in the loss of the TDRS satellite and would've almost inevitably resulted in the construction of Endeavour. If the crew did have to bail out at low altitude, they would've been able to fly Challenger south for the bailout and wouldn't have been more than five miles off shore.

With loss of life avoided, the atmosphere will be less somber, but it will be necessary for NASA to adopt the new version of booster, meaning a hiatus in launches until the new design is finalized, ordered, and produced; it probably requires a campaign of firing tests too.

The redesigns to the SRBs were ready within two years, so they may have only decided to suspend flights in cold conditions. This still may have resulted in a LOM/LOV/LOC if they had a particularly bad O-ring.

It could be worse than OTL, I guess, the O-Ring could fail within seconds of booster ignition causing the tank explosion while the Shuttle is still on the pad, wrecking the pad. In this circumstance, the blast from the tank explosion would impact the Orbiter worse, due to happening at low altitude, in denser air with lower, very subsonic airspeed. I don't know if it is known absolutely whether the crew was killed instantly when the blast wave from the tank hit them, or if they died later, of injuries during descent or with the final impact on the sea.

The ET would not have exploded, even at low altitude. The hydrogen and oxygen simply would not have been able to mix fast enough to prevent a very large proportion of the gases from simply being blown away by the pressure wave. The orbiter would probably have stayed attached to the ET's structure if the ET had not collapsed by then. There wouldn't have been enough time for the strut to have been melted away. In the actual incident, the orbiter disintegrated due to off-axis air pressure loadings that occurred when the strut failed and the right SRB swung off-axis. The deflagrating fuel from the breach in the ET had nothing to do with the breakup. During the breakup, the crew cabin became separated from the vehicle and remained intact until it impacted the ocean downrange.

If they were known to survive for a while after the explosion I'd say they might have a chance with a pad explosion, but the blast being relatively more powerful, probably not. If they were known to be dead with the blast OTL, surely this surface blast will kill them too. If they could survive the initial blast, presumably the Orbiter would fly off like a kicked football, very likely breaking up, and if not, it will land going crunch somewhere, on land I think most likely because I think the Orbiter faced inward from the shore. That crash landing seems likely to finish the job of killing any crew left alive by the blast and spin.

Even when rockets fly upwards and then crash down on the pad, they do not explode. The downward motion of the fuel at the time of impact simply compresses it more, which results in better fuel mixture and therefore more energy release. Think of how a meteor releases energy throughout its passage through the atmosphere, not just at the time of impact. If the SRBs start and do not blow themselves up instantly, you are going somewhere, and you will be going there until either the boosters burn out or the stack disintegrates. If you jettison the SRBs mid-burn, they will fly ahead of the stack and torch it with exhaust. When the ET tank structure fails, the fuel will deflagrate. There will not be any explosion, and an impact strong enough to knock the Orbiter around "like a kicked football" would destroy it before any motion became apparent. The orbiter faced south on the launch pad and rolled to face east (i.e., on the east side of the stack) so it would be facing down, with LOS to the communications relays at KSC, during the stack's gravity turn.

No telling what the Orbiter would crash onto. What if it hits the VAB?

The shuttle only gets that far under manual control. No pilot is going to intentionally crash into the VAB.

Meanwhile the tank going boom on the ground is likely to kill some more people I'd think--unless observer zones were set up with a most pessimistic estimate of possible blast energies, which they ought to have been.

Again, the tank is not going to explode. US rockets launch over oceans so pieces don't fall on land, and any vehicle - manned or not - that strays too far off its flight path will be destroyed in flight. The exclusion zone around the pads were made with N1-style failures of the Saturn V in mind. That failure mode simply cannot happen with the shuttle because of the solid boosters.

So best case scenario, on this launch or an earlier one, an O-ring failure that produces a spectacular gusher of fire squirting sideways away from the fuel tank causes a degraded mission as the Orbiter reaches orbit but falls short of mission target. NASA cannot shrug it off, especially when people realize what would have happened if the torch had been pointed inward and that there is no particular reason it shouldn't have been. All launches go on hold while the new booster design is ordered and procured.

This would be a rather iffy scenario. The asymmetric thrust would probably be controllable given the SSME's vectoring capabilities, but something the scale of the O-ring failure Challenger saw would be hard to handle. A minor booster redesign could probably be complete in a few months, with testing. If that for a few years, we might see ASRMs or even five-segment booster coming on line to replace the original SSSRBs.

But with Challenger surviving, there is never any authorization to construct Endeavor. As the fleet nears EOL, there is no young, ultralight version in the inventory.

Endeavour was not ultralight, Columbia was just a bit heavier than the other shuttles. Endeavour was built to the same design as Discovery, Atlantis, and Challenger and was never treated as anything other than a standard shuttle, while Columbia was restricted from flights to the ISS because it did not have sufficient payload margins.
 
As an aside, I always hoped to have seen two STS in space at once. Was this possible with the single launch site?

Let's say Challenger is damaged, and can't return without repairs in space. Could NASA send another Shuttle to undertake repairs? Certainly looks possible here.

Space_shuttles_Atlantis_(STS-125)_and_Endeavour_(STS-400)_on_launch_pads.jpg


However, is this possible in 1986? There's no large IST to support Challenger's crew if onboard life support systems and provisions are exhausted.
 
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The Shuttle was always operating in regimes that, had something gone just a little worse, would have meant loss of mission and loss of crew. All the way back to STS-1, for example, there were problems with tiles falling off the wings, resulting in thermal damage. Sooner or later, particularly as NASA tries to ramp up to 24 flights per year, something is going to cause a tragic accident.

But it would be rather boring to say "the next flight has a fatal accident and things proceed mostly as IOTL," so let's consider what happens if the Shuttle program's luck holds out and we go to 1992 without a fatal accident.

Shuttle-Centaur flies, and Galileo gets to Jupiter sooner, and with a functioning main antenna. Shuttle flights from VAFB to Polar Orbit commence. There might be a Wet Workshop experiment with the external tank, though that would probably just prove that Wet Workshops give you a lot of pressurized volume but not much else.

Without the Challenger Disaster or something like it, there's no Ride Report. NASA's mode of operation is "routine space travel with the Shuttle," with a long-term goal of building a space station. There remains very little official discussion of manned flight beyond Low Earth Orbit (essentially limited to the old Mars Underground), until 1989 at least. Bush Sr. was at least to a limited degree in favor of a bold leap forward into space (even if SEI was mangled by Dick Truly and the JSC Shuttle Mafia)--would he be content with continuing business-as-usual, or would he try to leave his own big mark on the space program with something like SEI? Without Truly in charge of NASA, could that be handled better ITTL?

Finally, what happens if/when the fatal accident finally comes? With most of the American expendable rockets out-of-production for years, how long would it take for the USAF to shift back toward something like the EELV program? Titan will have been out-of-production for years--there's no Titan IV ITTL. How long would it take to replace that capability?
 
As an aside, I always hoped to have seen two STS in space at once. Was this possible with the single launch site?

Let's say Challenger is damaged, and can't return without repairs in space. Could NASA send another Shuttle to undertake repairs? Certainly looks possible here.
Not in time with the state of orbiters IOTL. While NASA could put Orbiters on both pads and in theory could use this to arrange for a rescue to be waiting for any Orbiter not going to a station, they did not have any policy to do so IOTL. The next orbiter in rotation was Columbia, which was only ten days off her most recent flight and by no means ready to go in the week or so Challenger could have stayed on orbit.

The image you link is of Endeavour and Atlantis being prepared to do just that for STS-125--following Columbia, any mission not headed to ISS (which basically meant Hubble servicing and only Hubble servicing) would be required to have a fully-prepped "launch on need" backup mission ready to go. I happen to think it's a really pretty picture, but it's not NASA practice in the '80s...and it was pretty much a once-in-a-blue-moon think even on STS-125.
Presumably Challenger's crew could take refuge in the International Space Station if provisions or life support systems are exhausted onboard the shuttle.
Doesn't exist at the time.
 
Looking at the disaster it seems that had the crosswind that loosened the slag (which was warned about by a jetliner an hour before)
My POD is the crosswind is averted and Challenger escapes but a whistle blower (The chief engineer perhaps? Given he recognized the act of god and fate) lets loose the danger Challenger had been in after a successful reentry (No damage to the Shuttle, yet) to have America turn from pride and joy (It was a special mission) to horror and revulsion.

Of course getting Congress to make more money available so NASA isn't that pressured anyway is another matter.
 

Archibald

Banned
possible mission continuation depending on how badly off the boost phase is, possible once-around abort, possible abort to African landing field, possible crash in the Atlantic which the Shuttle could not do survivably, so everyone would have to improvise jumping out of the gliding orbiter on parachutes, which I presume were handy, and with life rafts which I hope were handy. If the aerodynamics of the Orbiter in glide mode even allowed for crew to bail out. They'd have to do it one by one and be scattered miles apart on the open ocean.
No matter what, with or without loss of crew, the mission will be badly impacted and attention focused on the problem.

Pre-Challenger ? no way. The way the shuttle entry/exit door was located (bottom side of the nose), any astronaut trying to jump would be smashed in two by the wing fat leading edge. The telescopic boom was especifically created to get astronauts out of the wing way.

though there would still be the unbalanced SRB thrust to deal with.

Good point.
The thrust inbalance by the leaking SRB was pretty severe and 72 seconds of flight is only halfway to 120 seconds and SRB jettison.
- It isn't possible to jettison a SRB at 80s or 100 seconds - thrust still to high, it would rip off the tank.
- also not possible to detach the orbiter from the stack, not with SRBs still firing

Within the last ten seconds (before the flame punctured the tank) the SSMEs were swivelling like crazy to try and correct the unbalanced trajectory, to no avail.
At some point the difference in thrust between the SRBs would have been such, the whole stack would have cartwheeled and been smashed to bit by the aerodynamic forces well past Mach 2.

Whistleblower Roger Boisjoly was scared that the shuttle stack might explodes on the ground, devastating Pad 39B. He couldn't believed the shuttle had lifted off without a glitch... and then the accident happened.

Had they survived the unbalanced thrust thing, all three SSMEs were intact and so would be the tank, so maybe they could have pressed to a very low orbit. At worse, TAL in Dakar, Senegal (one of the many delays that affected STS-51L was bad weather in Dakar.)
 
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Let's asume the Booster manage to keep seal or burn true on another side away from ET and Orbiter
So Challenger reach orbit, while the recovery team tow the two booster back to KSC

Here they will discover the hole or the internal Damage during cleanup and disassembly them.
It would be hard shock for Shuttle program managers and Close call for NASA Administration to take action
special after STS-2 flight had similar problem

First Grounding the Shuttle fleet until the Error in SRB is found
Likely that a whistleblower at Thiokol, reveal the Problem of Seals at low temperature
here NASA can do this resume Shuttle launch under ideal weather condition as "an acceptable flight risk". (no winter flights)
and push for the Advance Solid Rocket Booster to replace the current SRB on Shuttle to be ready for 1989/90

back to 1986 original it hab to be very busy launch schedule of 14 flights

STS-51-L 28 January TDRS-2 launch
STS-61-E 06 March ASTRO-1 mission
STS-61-F 15 May launch Ulysses probe with Centaur-G upper stage
STS-61-G 20 May Launch of Galileo probe with Centaur-G upper stage
STS-61-H 24 June launch three satellites, international crew
STS-62-A 1 July DoD mission first launch from Vandenberg AFB into Polar orbit
STS-61-M 22 July TDRS-3 launch
STS-61-J 18 August Hubble Space Telescope (hell there will be large disappointment)
STS-61-N 4 september a DoD mission
STS-61-61-I 27 September launch Intelsat-4 and recovery of LDEF
STS-62-B 29 September DoD launch from Vandenberg AFB into Polar orbit
STS-61-K 1 October EOM-1 mission
STS-61-L 1 November deployment of commercial communications satellites, first US american Journalist in space.
STS-71-B December a DoD mission

With SRB problem investigation and launch restriction STS-61-E/F/G are Cancelled and put on later date
seven launch will occur like DoD STS-62 flights from Vandenberg AFB and STS-61 H to I
while rest three flights are Cancelled and put on later date, do cold winter temperature
Until the the Advance Solid Rocket Booster are ready, it stay on 7 launch/year from KSC and several from Vandenberg.
The Shuttle will use the Centaur-G upper stage to launch space probes and Heavy commercial communications satellites.
from 1989 Advance Solid Rocket Booster offer save launch and more payload for Orbiter
NASA could increase the launch rate on planned 14/year

but still a Columbia stile disaster will happen
 

Delta Force

Banned
They were flying members of Congress as payload specialists. It's possible one of them might be caught up an incident. In fact, Representative Bill Nelson of Florida flew on STS-61-C, the last successful mission before the Challenger Incident.
 

Archibald

Banned
They were flying members of Congress as payload specialists. It's possible one of them might be caught up an incident. In fact, Representative Bill Nelson of Florida flew on STS-61-C, the last successful mission before the Challenger Incident.

Yes, and he was pretty lucky to save his life (that the two bullets I mentionned earlier)

There was a glitch somewhere so they postponed the launch and then while checking the shuttle they found a temperature probe that had broken and fallen into a SSME turbopump. The SSME would have exploded into a deadly rain of hot metal, trashing the orbiter rear structure.

Then there was another delay and a quantity of LOX got out of the E.T without anybody noticing, had the shuttle lifted offf they would have fallen short of LOX during ascent. Both troubles were caught in time, but only through pure luck.
 

GarethC

Donor
Previous thread here.

From apocryphal memory, Thiokol did blow the whistle - they had a call with NASA the night prior to the launch where the Thiokol engineering team said that the weather was out-of-parameter for launching and they should postpone. There is no log of the NASA response on the call, but the launch went ahead and all the astronauts died.

I chased up the Senate investigation report (love the internet!) a while ago - I'd read Surely You Must Be Joking, Dr. Feynman (which is a decent read) and has a chapter on the commission's work, and his point was that NASA management had groupthunk themselves into an echo chamber that did not allow for engineers - NASA's own, or contractors - to naysay their assessments of risk. NASA management's tolerance for error margins was based on wishful thinking about the ineffable eliteness of the manned space programme, not any actual quantitative assessment. So frankly, NASA was going to continue to make the launch schedule until there was a loss of mission accident, and it is unfortunate but completely unsurprising that it involved the deaths of the crew.

What was striking, actually, was the Columbia accident report. What really stood out was that the Columbia crew died for the same reason - of decision-makers responding to engineers' assessments with a three-monkeys la-la-la I can't hear you approach - that was exactly the same as was castigated after Challenger. I don't know whether there was a temporary change of management culture after Challenger which was then hounded out by austerity until Columbia, or if the culture never changed but just got by on the post-Challenger fixes for a while, but either way it looks at first glance that STS-51-L dodging the O-ring bullet will yield no more than a temporary reprieve, and that there will be no systemic improvements before a later catastrophe.
 

Archibald

Banned
Amen to that.
NASA did improve things after Challenger, until Dan Goldin cut 20% of the shuttle budget between 1992 and 2001, plus a culture of autoritarism that led to STS-107.
 
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