Get out of the way: The 1st restartable solid rocket fuel could help reduce space junk (op-ed)

[Admin]

Researchers at Los Alamos National Laboratory recently developed and demonstrated the ability to stop and restart solid rocket motors many times — something that has never been done before.

Get out of the way: The 1st restartable solid rocket fuel could help reduce space junk (op-ed) : Read more

 

[Sergiy Fakas]

You are wrong - this engine is not the first ever restartable solid motor in the world. Back in 80-th I've seen soviet classified solid motor able to restart up to 10 (may be) times. It was operational and used for spy sat corrections/film return capsules drop. It uses special powder to extinguish burning and igniter to start engine again.

 

[dfjchem721]

Hello Sergiy, raketa toplivniy*?

I believe you. The CCCP was excellent at engineering, and the Russian space program today is no different. And they have an outstanding record on safety. No fatal Soyuz launches, and the recent aborted launch worked perfectly - with no injuries. I do not recall that a launch ever had to eject the capsule during flight. Was this the first time?

Do you think these rockets you mention are sill being used by various satellites? It sounds like what you are referring to is small scale for orbital adjustments.

The proposed rocket engine here is not exactly new, but also is for orbital corrections. The generation of H2 and O2 from water is something I had not heard of, but the basic design sounds similar to others.

Solid rocket boosters (SRBs) were on the space shuttle because restartable rockets are probably not optimal for launching , at least not with current technology. Even if they were, you do not want to stop rockets during launch, so the SRBs will probably play a role in heavy lift operations for quite a long time to come.

The restartable rocket I remember from some time ago used a solid propellant fixed to the wall of the booster, and O2 injected into this chamber from above. Once ignition begins, the solid fuel is burned off to provide thrust. The supply of oxygen is what makes it restartable. The solid fuel burning can only continue as long as oxygen is injected. So it is easy to stop by simply cutting the flow of O2. Need it again? Just start pumping in O2 and reignite the rocket. You can control start, stop, and thus burn times just by the O2 flow to the combustion chamber.

Have you ever heard of such a rocket? I bet the Soviets worked on something like that also.


* I got this Russian phrase off the internet - solid fuel rocket. If you respond with any Russian, I might have a problem reading it. Let's stick with English!!

 

[Sergiy Fakas]

Well... Russian space program is dead now. They are building Angara since 1994 and all they did is the wasted launch complex at Vostichniy.
I doubt if the engine I mentioned is in use now. Monopropellant engines are better for this purpose.
As for "a solid propellant fixed to the wall of the booster, and O2 injected into this chamber from above". It is called hybrid engine. From my knowledge Virgins SpaceShip Two uses it. Never heard it to be developed in the Soviet Union.
The main advantage of hybrid rocket engine it comparing to solid motors is not ability to restart but thrust throttling. Solid rocket can't change thrust flexible – thrust throttling depends n the shape f the charge burning. Hybrid rocket is able to change thrust by increasing or decreasing oxidiser flow.

 

[dfjchem721]

"Russian space program is dead now." Sorry to hear that. I was not aware, but I do know that all of Russia has serious financial problems. A shame for all the real people there. Many good people in Russia, they never seem to get a good chance. I have read most of Dostoevsky novels.

They still have an excellent Soyuz program. We even use it! Imagine that, Americans relying on the Russians to put our people into space. That tells you how much NASA trusts our Russian partners! A whole lot!!!

Yes, thrust throttling is something I had forgotten about with hybrid engines. A major advantage. I suppose you could even carry extra propellant in order to re-line the thrust chamber once it is exhausted.

The shape of the charge burning reminds me of how the wall of propellant might be formed in the rocket chamber. For maximum thrust one uses a convoluted pattern giving for maximum thrust. Perhaps star-shaped to maximize surface area.

Are you a "rocket scientist"?!

 

[Sergiy Fakas]

I'm not russian. Russia is kills our citizens just 400 km from my home. NASA must stop cooperating with Roskosmos led by Rogozin who is complete idiot and responsible for full degradation of the space industry in Russia. Just look at Sea Launch ships which were moved to Russia from Long Beach and now owner must pay twice as it had to pay in the US port.
Yes, I'm graduated rocket engine engineer but did not have a chance to work as rocket engineer.

 

[dfjchem721]

I had no idea you were not Russian. Where are you from?

And the Russians are still good people, it is their government that is the problem. That seems to be true in a lot of countries. I have read that Iranians hate America, but love the people and our culture. It is clearly all about the governments.

Was not aware that there was so much trouble with Roskosmos. U.S. will not stop working with them because the fools in our government ended the space shuttle program with three prime shuttles that could be used for years to come.


Sorry you cannot work in your profession. Where did you get your degree?

 

[Sergiy Fakas]

I'm fro Ukraine. I've graduated airspace university in 1993. Soviet Union was preparing rocket engineers in huge amounts - there were about 200 students who graduated in the same year and as rocket scientists.

 

[dfjchem721]

Now I understand. There are very bad things going on in your country, with all the fighting in the east and seizure of Crimea. My apologies for assuming you were Russian. I think all that happened because of Putin. Most of the Russian people do not support him anymore.

When you noted having seen Soviet engine designs, I made a stupid assumption. Someone else made stupid assumption about U.S. funding of Ukrainian military.

Have also read much about World War II and the Ukraine. Also very bad blood, going back to Soviet revolution. The Ukrainians don't have much luck either, it seems. If it is not the Russians, it is the Germans, then the Russians again. It is a shame your country is not more prosperous.

Did you have a specialty in rocket design, or is your degree in all aspects of their design?

 

[Sergiy Fakas]

My speciality was liquid propellant rocket engines with some knowledge of solid rocket motors.

 

[dfjchem721]

So Sergiy, you must follow some of the many dreams about people building habitats on the moon and Mars.

What do you think of the probability of those? It would take a lot of launches to get everything into orbit before you even begin the journey, and then you need to burn a lot of fuel to bring all that mass to escape velocity from earth. If I remember, that is about 11km/sec. Which is much faster than low earth orbit.

Perhaps a hybrid engine would work well for powering the trip to other places. As I noted, you could always replace the fuel in the chamber, since the weight of the rocket housing and other parts is much more than the fuel. But you are the real rocket scientist. Tell me if you think this will ever happen and how is the best way to do it. Clearly getting everything up there and on its way will take a lot of collective thrust.