Russian Supply Rocket Malfunctions, Breaks Up Over Siberia En Route To ISS (npr.org)

An anonymous reader quotes a report from NPR: An unmanned cargo rocket bound for the International Space Station was destroyed after takeoff on Thursday. The Russian rocket took off as planned from Baikonur, Kazahkstan, on Thursday morning but stopped transmitting data about six minutes into its flight, as NPR's Rae Ellen Bichell reported: "'Russian officials say the spacecraft failed [...] when it was about 100 miles above a remote part of Siberia. The ship was carrying more than 2 1/2 tons of supplies -- including food, fuel and clothes. Most of that very likely burned up as the unmanned spacecraft fell back toward Earth. NASA says the six crew members on board the International Space station, including two Americans, are well stocked for now.'" This is the fourth botched launch of an unmanned Russian rocket in the past two years. Roscomos officials wrote in an update today: "According to preliminary information, the contingency took place at an altitude of about 190 km over remote and unpopulated mountainous area of the Republic of Tyva. The most of cargo spacecraft fragments burned in the dense atmosphere. The State Commission is conducting analysis of the current contingency. The loss of the cargo ship will not affect the normal operations of the ISS and the life of the station crew."

Comments

Tuva or bust!

[orzetto]

[...] over remote and unpopulated mountainous area of the Republic of Tyva

Apparently, it was rather Tuva and bust .

um

[Anonymous Coward]

BASIC astrophysics: it's the horizontal velocity that matters. If it were not for obstacles and atmospheric drag slowing you down, you could orbit the Earth at 5000 feet. You can certainly orbit the moon (which has essentially no atmosphere) or any similar body at any altitude.

During WWII German V-2 Rockets flew to as high as 206 km (128 miles) which is space, but they never had even a third of the horizontal velocity to achieve orbit. It's that horizontal speed which causes things reentering the atmosphere to heat up and burn, and the lack of that horizontal speed is why V-2 rockets, Spaceship One, Spaceship Two, and the Red Bull parachutist could all plunge back to Earth from space without heat shields.

To orbit the Earth, you must be going "sideways" so fast that as the Earth's gravity pulls your trajectory "down" (towards the center of the Earth) you've moved "sideways" far enough for the Earth's curvature to equal that bent trajectory. That's about 14500MPH for low Earth orbit. Most rockets burn an enormous amount of fuel initially getting off the pad and climbing vertically to get up out of the thick lower atmosphere quickly, but then execute a "gravity turn" in the upper atmosphere so that they then spend most of their fuel thereafter building up the great horizontal velocity needed to achieve orbit. This Soyuz apparently had a third stage failure, so it was plenty high but unable to continue accelerating to orbital velocity - it was doomed the moment the third stage either shut down or failed to ignite.

Re:um

[MachineShedFred]

Usually they don't wait for upper atmosphere for starting the gravity turn - Apollo started the roll and pitch program at 15 seconds into flight, having only cleared the tower 5 seconds before. For altitude reference, the Apollo 11 flight plan has them passing 14,000 feet at 51 seconds into flight.

But you are correct - orbit is mostly not about altitude, rather it's about going fast enough horizontally to continually fall back to Earth and miss.

Re:um

[Opportunist]

You should probably add that one of the key reasons for this being that they don't want debris to fall back down onto the launch facility, either 'cause something goes wrong early on or because a stage gets jettisoned.

Also, it is actually more economical to start the turn early on, it gives you a way better flight profile that also puts less stress onto the parts.

Re:Hmmm....

[K. S. Kyosuke]

with 30 years of flawless flights

There actually seems to be one failure every several years in that time period, but given the very high flight rate of that vehicle, that's not shabby at all.

Re:almost made it

[Rei]

Unlike the others, I'm going to assume that you're saying "at 190km, they must have also been far enough along into the burn that they also had significant horizontal velocity" :)

And yes, like the overwhelming majority of modern Russian launch vehicle failures, this was an upper stage failure. Their lower stages have been reliable workhorses, but they've long struggled with upper stages.