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We want Solid Fuel tanks/Canisters maybe you can just configure current tanks so you can put Solid fuel or LF OX and also be able to get Solid fuel to 1 or 10 because the lowest is 20 for some god damn reason

Edited by Kroslev Kerman

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But then we would need solid fuel engines. 

Now we have four different configurable boosters, both in terms of amount of fuel and thrust, what more do we need?

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2 minutes ago, The Aziz said:

But then we would need solid fuel engines. 

Now we have four different configurable boosters, both in terms of amount of fuel and thrust, what more do we need?

Stackable solid fuel tanks with forced priority that can have different thrusts applied during the burn to "shape" the SRB thrust curve.

Which would be really cool, but not sure if it's appropriate for stock.

Edited by Geonovast
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oh this sounds cool  Would love to see something like this but probably a mod

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6 hours ago, Geonovast said:

Stackable solid fuel tanks with forced priority that can have different thrusts applied during the burn to "shape" the SRB thrust curve.

Which would be really cool, but not sure if it's appropriate for stock.

Isn't exactly the opposite (as in: cannot shut down, constant thrust until depleted) one of the things that make the definition of solid rocket booster?

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39 minutes ago, The Aziz said:

Isn't exactly the opposite (as in: cannot shut down, constant thrust until depleted) one of the things that make the definition of solid rocket booster?

Real SRBs can have their fuel grain geometry tuned at construction time, which gives you the ability to set a throttle curve. Of course, this can't be changed once the booster is assembled, but still.

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13 hours ago, Kroslev Kerman said:

We want SRB Fuel tanks maybe you can just configure current tanks so you can put Solid fuel or LF OX and also be able to get Solid fuel to 1 or 10 because the lowest is 20 for some god damn reason

So you can add more fuel to your boosters? That would be nice

8 hours ago, The Aziz said:

Now we have four different configurable boosters, both in terms of amount of fuel and thrust, what more do we need?

According to some people we need everything

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3 hours ago, The Aziz said:

Isn't exactly the opposite (as in: cannot shut down, constant thrust until depleted) one of the things that make the definition of solid rocket booster?


While solid boosters can't be shut down, they can be made to produce zero net thrust - which amounts to the same thing in the vast majority of cases.

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Solid boosters can be shut down, if engineered so.  You can choose a propellant combo that requires a surrounding pressure (supplied by the atmosphere on the ground at ignition, and by combustion products in flight) to sustain combustion.  Vent the interior pressure by explosive doors, pressure drops to zero, thrust terminates.  But that imposes constraints on your choice of propellant - another option as Derek mentions is to use a propellant that continues burning in vacuum, but use similar ports with shaped nozzles that redirect some thrust opposite the main nozzle.  You can do it to yield zero net thrust, or even net reverse thrust to ensure a dropped stage moves away from the vehicle at staging events.  Google on 'thrust termination ports' if you're curious - these have been commonplace on solid-fuel ICBMs like the Minuteman III, SLBMs etc.

Such devices have been critical to ICBMs, where payloads are fixed size, cost is no object, and the goal is to accurately target any arbitrary point on Earth with a suborbital flight.  If your goal is simply to carry more mass to orbit than the other guy in the global orbital service market, these things are simply dead mass and extra cost - which is why they're not used on the launch vehicles most KSP players are familiar with.  And indeed, in later generation strategic missiles (for instance LGM-118), designers have often turned to more flexible liquid fueled final stages with simple non-terminated solid boost stages. This lets you control trajectory with fewer moving parts and a smidge more efficiency - and being restartable, you can now spread your MIRVs over a colossal area presenting a more difficult target to strategic defenses.  And being a tiny final stage, it doesn't present the extreme hazards of giant quantities of storable propellants for main boosters.

Some light reading:

https://charlesvono.com/minuteman-thrust-termination/

https://www.researchgate.net/publication/245434781_Thrust_Termination_Dynamics_of_Solid_Propellant_Rocket_Motors

https://www.eba-d.com/capabilities/missile-aircraft-and-space-vehicle/flight-termination-systems/thrust-termination-destruct-charges/

https://pdfs.semanticscholar.org/e002/369606d9c1e896494b9de77ec665849d97a6.pdf

https://ntrs.nasa.gov/search.jsp?R=19620004856

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On 11/24/2018 at 10:55 AM, fourfa said:

And indeed, in later generation strategic missiles (for instance LGM-118), designers have often turned to more flexible liquid fueled final stages with simple non-terminated solid boost stages.

Nit:  The USAF has used liquid fueled final stages (actually a PBCS) since the MMIII (LGM-30G) was deployed in 1970.  The Navy absolutely loathes liquid fueled missiles, so US SLBMS have always used a hot gas powered PBCS.  (First flown on Poseidon in 1971.) 

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I reckon a tuneable thrust curve could be implemented (even with only 3 or 4 points) though I'm not sure how the VAB interface would work.

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