Gazelle and Sprint - fastest rockets ever?

[1greywind]

I love reading about rocket. I knew about missile defence systems developed and built by USA and USSR during Cold War: "Safeguard" and "A-135". But I haven't had understanding how fast missiles used in this system were: they were (and are) not just "fast", they are insane-blazing-faster-than-you-may-imagine fast. Don't believe me?

Let's define "fast" in terms of acceleration: typical KSP rocket accelerates at about 1.5-2 G (15-20 m/s in second). If we strap Mainsail engine to smallest fuel tank and launch it in full throttle we get ~25 G.

But real life rocket were much faster that 25G! The Sprint close range missile of Safeguard system had acceleration packing at more that 100g! And soviet Gazelle (it is still in service in Russia) is event fast with max acceleration at 200g! This is mind blowing: in just 4 second rocket accelerates to >5 km/s still within atmosphere!

[table=width: 1000]

[tr]

[td]Name[/td]

[td]51â6 Óð÷õûь (ABM-3 Gazelle)[/td]

[td]Sprint[/td]

[/tr]

[tr]

[td]Country[/td]

[td]USSR[/td]

[td]USA[/td]

[/tr]

[tr]

[td]In service[/td]

[td]1988[/td]

[td]1972[/td]

[/tr]

[tr]

[td]Max speed[/td]

[td]>5 km/s (mach 17)[/td]

[td]>3 km/s (mach 10)[/td]

[/tr]

[tr]

[td]Max acceleration[/td]

[td]~200g[/td]

[td]~100g[/td]

[/tr]

[tr]

[td]Stages:[/td]

[td]1[/td]

[td]2[/td]

[/tr]

[tr]

[td]Operational range:[/td]

[td]80 km[/td]

[td]40 km[/td]

[/tr]

[tr]

[td]Weight[/td]

[td]10 t[/td]

[td]3.5 t[/td]

[/tr]

[tr]

[td][/td]

[td]

[/td]

[td]

[/td]

[/tr]

[/table]

Contemporary USA's midcourse intercept anti missile defense system is more effective, but much less spectacular. I wonder, are Sprint and Gazelle fastest rockets ever built or not?

Edited December 4, 2014 by 1greywind

[problemecium]

I think you mean "mach" but your thing seems to have autocorrected it to "march" in the "max speed" row.

[1greywind]

I think you mean "mach" but your thing seems to have autocorrected it to "march" in the "max speed" row.

Thx for correction.

[Idobox]

I just checked the wiki on the gazelle and sprint to try to find out how the hell they managed this kind of acceleration and deltaV.

Not a lot of info on the gazelle, but for the sprint they say :

"The first stage, Hercules X-265 engine, is believed to have contained alternating layers of zirconium "staples" embedded in nitrocellulose powder, followed by gelatinizing with nitroglycerine, thus forming a higher thrust double-base powder."

Nitrocellulose mixed with nitroglycerine is known as smokeless powder, and is the most common type of propellant for guns, from hand guns to naval artillery. And they added zirconium, I suppose because aluminium was not reactive enough.

This rocket is pretty much a big bullet with the propellant exploding slowly.

[shynung]

Nitroglycerine!? That's a highly-explosive material used in early dynamite sticks. I wonder if the engineers who built this thing has lost a few fingers during his careers.

[Sandworm]

100g+ rockets are not rare. Thousands, possibly millions, have been fired. Google "FFAR" for Folding Fin Aerial Rocket. Those little guys pull 100+Gs getting out of their tubes. The Canadian CRV7 is probably the fastest accelerating and is famous for being more accurate than the 20mm cannons mounted on many aircraft. I believe they top out at around 3000m/s, but that's impressive given their size/price. There are even stories of practice rockets (no warheads) punching holes through tanks.

Edited December 5, 2014 by Sandworm

[rdfox]

Engineers who witnessed test launches of Sprint described it as less of a launch and more of an explosion.

As a side note, the silo launcher was essentially a cannon that fired the missile into the air before it ignited, to further speed launch.

[AcidSludge]

Someone has to strap some GoPros or something to that.

[SciMan]

... I have a feeling that a GoPro would break due to the stress breaking the chips off of the circuit boards. Also, if you watch that Sprint ABM launch video, you can see the outside of the missile getting red hot near the end.

In other words, the Sprint ABM is an IRL missile that gets "re-entry effects" on the way UP.

[1greywind]

Someone has to strap some GoPros or something to that.

Gazelle nose cone temperature reaches up to ~2000 degrees. Even if GoPro will survive 200g of acceleration it will be evaporated during "reverse reentry".

[AcidSludge]

They should do it anyway. You know, for SCIENCE!.

Also they have to add bananas.

[Voidryder]

I say the heck with GoPro. Strap Jeb to one. heh heh heh

[SubzeroSpartan7]

The SpaceLoftXL takes 90 seconds to reach space which is impressive, but these are insane. What did they even think about doing with these?

[rdfox]

The SpaceLoftXL takes 90 seconds to reach space which is impressive, but these are insane. What did they even think about doing with these?

Last-ditch endoatmospheric intercept of incoming ICBM and SLBM warheads; Sprint had a maximum range of 40km and a maximum altitude of 30km. These were not space launch boosters, but defensive weapons that, due to the high speed of their targets, had to react incredibly quickly. More information here: https://en.wikipedia.org/wiki/Sprint_%28missile%29

[Triarius]

It occurred to me in contemplating this missile that at 100G, covering 500m in the first second, it will outrun a handgun bullet at that range. At a range of 1 km, this missile has already passed concurrently fired .50BMG, and that's completely neglecting friction (bullets slow down IRL). Breathtaking.