I've read several articles about the new Angara rocket, that called it clean/eco-friendly. I know it runs on kerosene (and LOX), which is not super-toxic like hydrazine, but still... it's polluting the air, right?

Also, I've never heard Falcon/Atlas/Delta or any other kerosene rocket called eco-friendly.

So my question: Are there any aspects of Angara which deserves the eco-friendly term, or is it just "marketing"?


1 Answer 1


When you compare the waste products of LOX/Kerosene vs hydrazine/MMDH/etc, it is actually not too terrible at full combustion. (End up with CO2 and water, or CO2, Ammonia, and water).

However, if say, a fully fueled Proton looses control say 50 seconds into flight and collides with the ground, literally a million lbs of hydrazine is the definition on Unenvironmentally friendly. While the Proton is very reliable, this has happened twice recently, once in July 2013 and again in May 2014.

Also since Russia has no good coastal launch sites, they have no choice but to drop stages that never have completely used all their fuel over land, which is no fun wherever it lands. (Mostly in barren desert).

It is fundamentally the difference in the fuels.

Now technically LOX/H2 is better than LOX/Kerosene, but Hydrazine is so bad, it is worthy of the designation for switching to Kerosene.

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    $\begingroup$ The nitrogen in hydrazine and other nitrogen-containing fuels isn't all going to end up as ammonia. (In fact, at "full combustion", there shouldn't be much if any ammonia at all.) A lot of it will end up as harmless dinitrogen gas, but there will also be all sorts of nitrogen oxides, which are generally not nice things to scatter around. With incomplete combustion, you can end up with even nastier combustion products (although, admittedly, few as toxic as hydrazine / MMDH / etc. themselves). $\endgroup$ Dec 23, 2014 at 15:57
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    $\begingroup$ (Cc: @IlmariKaronen) Indeed, the reason that nitrogen-containing substances burn or explode so energetically is that the nitrogen-nitrogen triple bond in N2 is so stable. You have to put in huge amounts of energy to break the N-N bond; in the case of a fuel or explosive, that's the energy you get back when the N-N bond forms. $\endgroup$ Dec 23, 2014 at 22:15
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    $\begingroup$ I couldn't tell if your comment about the Proton failing was sarcastic or not, so I looked up the launch info from 2000 - 2009 and 2010 - 2014 and found two first stage failures that looks like it would have impacted the ground. The rest are second stage failures which put the payload into an unsuitable orbit. $\endgroup$
    – Schwern
    Dec 23, 2014 at 22:32
  • $\begingroup$ @Schwern It was sarcasm and a fully loaded Proton had the inertial sensors upside down or somesuch and made it up a short distance, then right back down, big mess. I forget the mission, could not be bothered looking it up. Would you please edit it into the answer for me? $\endgroup$
    – geoffc
    Dec 23, 2014 at 23:09

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