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64 votes
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Did the Challenger SRBs fail due to design for reuse?

The O-rings and the temperature were only the last in the long chain of blunders, and that had little to nothing in common with reusability. The construction of the SRBs wouldn't be much different ...
SF.'s user avatar
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61 votes
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Could the shuttle wait out the whole burn of SRBs on launchpad in case of a problem on launch?

No. Compare Space Shuttle Launch Countdown. The SRB fire command and the hold-down fire commands are issued at the exact same time. The delay of about 6 seconds (note: each SSME is started at a ...
ereisch's user avatar
  • 801
52 votes

Could the shuttle wait out the whole burn of SRBs on launchpad in case of a problem on launch?

I don't have an immediate citation handy, but the answer is no. The SRBs were powerful enough to overcome the hold-down studs. That said, the same signal was used to blow the nuts on the hold-down ...
Tristan's user avatar
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45 votes
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Why can solid rockets be both the skinniest and most spherical launch vehicles while liquid fuel rockets have a more limited range of aspect ratios?

The squat end of the spectrum has little to do with solids versus liquids and everything to do with aerodynamics. Spherical tankage is most weight-efficient, so you'd expect squat stages in cases ...
Russell Borogove's user avatar
44 votes
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Why didn't the SRBs of the Space Shuttle use carbon instead of aluminium?

Specific impulse is not the only measure of a rocket. For the case of the SRBs, high thrust is much more important than high specific impulse. In this case, you want to look at the heat of formation ...
Tristan's user avatar
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43 votes
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Does the Long March-11 increase its thrust after clearing the launch tower?

Long March 11 is a cold-launched rocket, based on a concept popular with military rockets. A gas charge is generated by the launch platform (often using a chemical gas generator) to eject the rocket ...
Saiboogu's user avatar
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38 votes
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Why were they using segmented boosters on Space Shuttle?

Four companies submitted bids to build the solid rocket boosters for the Space Transportation System based on the requirements provided by the Space Shuttle Program. Three of the designs were ...
Organic Marble's user avatar
33 votes
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Challenger hypothetical - what if the SRB breach faced outboard?

Do we get to pick our assumptions? I don't see how to answer this otherwise. I'll assume the hole kept growing at a "slow rate" and the booster didn't come apart. (If the booster came apart, the ...
Organic Marble's user avatar
32 votes
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How were the Space Shuttle SRBs ignited? (with what?)

SRB Ignition SRB ignition can occur only when a manual lock pin from each SRB safe and arm device has been removed. The ground crew removes the pin during prelaunch activities. At T minus ...
Organic Marble's user avatar
26 votes

Did the Challenger SRBs fail due to design for reuse?

Not reusability per se, but design and politics. The competitor to build the SRBs for the Shuttle program was Aerojet, and their design was monolithic. In other words, no segments. Aerojet was ...
Organic Marble's user avatar
26 votes
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What is the purpose of the aft skirt on the Space Shuttle and SLS Solid Rocket Boosters?

Main points about the SRB aft skirt are that they: bear the entire weight of the launch vehicle, prelaunch had (SLS SRB does not) four hold-down/support posts distributed the loads between the SRB ...
blobbymcblobby's user avatar
25 votes
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How does a single SRB control attitude?

The Ares 1-X used stock Shuttle program SRB thrust vector control (TVC) - hydrazine fueled power units drove hydraulic pumps which powered actuators that could tilt and rock the nozzle, which ...
Organic Marble's user avatar
23 votes
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What are they doing to this rocket following its test fire?

It's a quenching probe. After burnout of the booster was confirmed, a CO2 fire extinguisher was moved into the nozzle area to inject carbon dioxide into the booster to kill any remaining fire in ...
Organic Marble's user avatar
23 votes
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How would larger solid rocket boosters have improved the space shuttle's capabilities?

Five-segment boosters for shuttle were being actively developed prior to the STS-107 failure. (personal notes) The paper Five-Segment RSRB Feasibility Status (1999) predicts an increase in ISS ...
Organic Marble's user avatar
22 votes

Why didn't the SRBs of the Space Shuttle use carbon instead of aluminium?

You might be interested in the tool called cpropep. This allows us to gain basic performance indications for different fuels by solving the physics behind it: chemical equilibria and expansion/...
Christoph's user avatar
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22 votes
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Why do the Titan SRBs have an angled engine bell?

As Ohsin comments above, the SRB nozzles are canted to direct the thrust approximately through the rocket's center of mass. This prevents any imbalance in thrust between the SRBs from creating a ...
Russell Borogove's user avatar
21 votes

Could the shuttle wait out the whole burn of SRBs on launchpad in case of a problem on launch?

Could the shuttle wait out the whole burn of SRBs on launchpad in case of a problem on launch? No. The question seems based on the assumtion that something (the hold-down bolts perhaps) could hold ...
dotancohen's user avatar
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21 votes
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Is there documented Space Shuttle O-ring failures excluding STS-51-L?

Yes, several of the previous shuttle launches exhibited erosion and/or "blow-by" of the SRB O-rings, starting with the second flight, STS-2. Much has been written about the failure of NASA and Thiokol ...
Russell Borogove's user avatar
19 votes
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Why didn't the space shuttle SRBs have wings and tires?

Wings, engines to fly back to the launch site, and landing gear are heavier than parachutes. Using this design on the SRBs could have resulted in a significant payload to orbit reduction (every 10 ...
Organic Marble's user avatar
19 votes
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What are these circular spots on these Ariane V SRB nozzles?

Meet the Ariane EAP (Étage d'Accélération à Poudre, "Solid Booster Stage"): what are the (presumably eight) circular spots on the external nozzle-like protrusions at the bottom of each of ...
Russell Borogove's user avatar
19 votes
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Why was the Atlas V's SRB kept attached for 1 minute after burnout in the OFT-2 mission?

The solid rocket boosters are left attached because they don't want to separate them during the phase of highest dynamic loading of the vehicle. The risk of something going wrong during this critical ...
TrySCE2AUX's user avatar
  • 3,235
18 votes

Was a method available to save the Challenger Crew?

My reading of the function of the SRB manual separation control is that it would not actually trigger a separation while the boosters were firing (bold mine): SRB separation is normally performed ...
Russell Borogove's user avatar
16 votes
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Why were Solid Rockets chosen for the SLS

SRBs have a very high thrust to weight ratio, even if they have an only modest ISP. That makes it complementary with LH2/LOX systems that have a relatively low thrust. Early on acceleration is almost ...
SE - stop firing the good guys's user avatar
16 votes

Has an SRB been considered for use in orbit to launch to escape velocity?

This is referred to as 'kick stage' motor and is commonly used. One example being Star 37. A larger Star 48 is what sent New Horizons on the way to Pluto
kert's user avatar
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15 votes
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Why do the shapes of these two exhaust plumes from an Atlas V 411 look different?

Yes, the pressure of the first stage exhaust is always at least slightly subatmospheric, because that gives the maximum average ISP over the whole burn time. Rockets with boosters attached (parallel ...
Rikki-Tikki-Tavi's user avatar
15 votes

Did the Challenger SRBs fail due to design for reuse?

Technically, it was the O-rings, but that was not the root cause. The root cause was a poor culture at NASA. The technical solution was easy: Don't launch on that cold of a day. In Florida, even in ...
David Hammen's user avatar
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15 votes
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Features seen on the Space Shuttle's solid booster; what does "LOADED" mean exactly?

Image source The booster has two kinds of joints between its segments, field joints and factory joints. The booster parts shipped to KSC were made up of two segments joined by factory joints. At KSC,...
Organic Marble's user avatar
15 votes
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Is it possible to propulsively land an SRB?

Fundamentally soft landing a solid requires controlling the thrust. This is not totally impossible, as demonstrated by the Nulka system that hovers by adjusting away from the optimal nozzle shape to '...
GremlinWranger's user avatar
14 votes

How does a single SRB control attitude?

Apart from having an actuated nozzle, an inert gas or reactive liquid can be injected into the nozzle of an SRB to dynamically deflect or shape the exhaust, thereby vectoring the thrust. ISRO's Polar ...
Ohsin's user avatar
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14 votes
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How were STS SRBs disassembled

SRB segments for reference while reading this: The boosters were towed back to KSC by ship. This crane then lifted them out of the water... ...and placed them on this dolly which could move them ...
Organic Marble's user avatar

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