Soyuz TMA-11 Landing

[Scrooge McDuck]

And for the media guys out there, not reading a good forum: A ballistic reentry is still a controlled situation. It is not according to the flight plan, but the crew is not in danger. It is even much better as reentering with lift and possibly a wrong orientation of the capsule. (I think the reentry program switches to ballistic reentry when the G forces increase faster as expected - at least it would be one indication of a bad reentry)

Still we see everything getting over hyped, even an article on slashdot.

So whoever added this incident to the "Near fatalities" list on Wiki, was probably completely wrong? Read it here: http://en.wikipedia.org/wiki/Space_accidents_and_incidents#Near-fatalities
Of course, experiencing a very high-G force must have been terrible for the people inside, but if it has happened more than once, and if it's still controlled, it's no unique and no 'near fatal' incident.
Should we remove it from this list (if it wasn't near fatal at all, and if it also happened in the last flight too)?

regards,
mcduck

 

[C3PO]

I'm not an expert on the subject, but isn't this mode 'safer' than the lifting reentry? It would be pretty daft to use it as fail-to mode if it wasn't. It is more uncomfortable, but I don't think it's a safety issue.

I would guess that it's about as dangerous as the engine #5 shut-down on Apollo 13, and I don't hear anyone calling that near-fatal.

 

[Andy44]

From http://history.nasa.gov/SP-4029/Apollo_13a_Summary.htm

Between 000:00:12.6 and 000:00:32.1, the vehicle rolled from a launch pad azimuth of 90° to a flight azimuth of 72.043°. The S-IC engine shut down at 000:02:43.6, followed by S-IC/S-II separation, and S-II engine ignition. Due to high amplitude oscillations in the propulsion/structural system, the S-II center engine shut down at 000:05:30.64, 132 seconds earlier than planned. The early shutdown caused considerable deviations from the planned trajectory. The altitude at shutdown was 10.7 n mi lower and the velocity was 5,685.3 ft/sec slower than expected.

The Apollo 13 S-IVB anomaly was indeed very serious, and had the engine not shut down when it did, could have been catastrophic. The deviation in flight plan, was, again, a serious anomaly. The whole thing resulted in technical investigations and engineering changes to prevent it from happening on future missions. These things aren't exciting to hear about, so you don't hear about them in the news, especially in this case, since Apollo 13 suffered a much more serious anomaly which would overshadow the Saturn problem.

I stand by my earlier statement: what happened to TMA-11 should not be glossed over as no big deal. Given that this is not the first time, someone needs to look at the the project leadership and say "Hey, WTF?"

Spaceflight is not like driving a car. When things go wrong, you investigate, find out why, and fix it. You don't keep kicking the can down the road (ahem, like the o-ring problem). It's risk management 101: the consequences of a re-entry anomaly can be very high, even resulting in death of personnel, therefore you must lower the probability of re-entry anomalies to an extremely low number.

3 times in 5 years is not low enough, try again.

 

[Scrooge McDuck]

I stand by my earlier statement: what happened to TMA-11 should not be glossed over as no big deal. Given that this is not the first time, someone needs to look at the the project leadership and say "Hey, WTF?"

True, but still it probably wasn't a so called "near fatality", as mentioned on Wiki.
Btw, just looked at the Wiki page again, and saw it was removed from the list, by some Andy , thanks.

regards,
mcduck

 

[Andy44]

Wasn't me, I have no wiki privs...

 

[Scrooge McDuck]

Everyone has. But whoever it was, I think it's good now. The fact that someone called Andy changed it was a coinsidense then.

regards,
mcduck

 

[Marcel]

Anybody hear how Peggy Whitson is doing? I read that she looked pale and wasn't up to meeting with the public after the landing.

 

[Urwumpe]

Anybody hear how Peggy Whitson is doing? I read that she looked pale and wasn't up to meeting with the public after the landing.

That's not unusual. Astronauts who spent a long time in micro-gravity need some days to become used to Earths gravity again. She also had a high-G reentry behind, which is additional stress for her weakened circulatory system.

She'll be fine, at least according to the statement of the Russian flight medic. He was not too happy, but also not concerned.

 

[ryan]

The flight medic or surgeon are never happy, becuase the astronauts or cosmonauts never do what the doc says them to do.

 

[simonpro]

Andy, yes the ballistic landing incidents are serious. But they are not a reason for grounding soyuz (which we can't do anyway, else the ISS would be empty).
The incident on Soyuz-TMA 1 was an extremely rare possibility of the attitude measurements being such that an incorrect yaw command was sent. The chances of this occuring at thousands-to-one: As demonstrated by this never happening on any mission prior to TMA-1 (even though the same control unit type had been in use for the previous quarter of a century).
This problem was resolved post-flight, and upgrades prevent it from happening again.

The last Ballistic descent was, as I already said, caused by bad wiring. Looks like this was caused by the same thing.
Basically it's a question of increased quality control during manufacture, and as such isn't a fundamental flaw in the vehicle.




Ryan, all the flight surgeons I have worked with have been incredibly happy people actually. They seem to act like lightning rods, attracting all the happiness whilst those around attract all the nervousness. It's quite funny to watch.

McDuck: It was me who edited the Wiki article.

 

[Andy44]

Well, I didn't say it should be grounded. If that's what the press is saying, well, like you said, they are sensationalists.

 

[reverend]

Yea, to ground soyuz would mean abandonment of ISS... Even with a ballistic re-entry as uncomfortable as it is, this problem will be corrected on future vehicles, and would be in no way worth abandoning the (trillions?) of dollars spent to get the space station to where it is today...

 

[Belisarius]

Video report on the landing from the BBC

http://news.bbc.co.uk/2/hi/science/nature/7356520.stm

 

[SiberianTiger]

Now see what happens when you are away on the days off and is not tracking how the things are going. :blink: Looking forward to the Monday's news and comments.

 

[Urwumpe]

Now see what happens when you are away on the days off and is not tracking how the things are going. :blink: Looking forward to the Monday's news and comments.

Yeah, you should have been there, pushing the "nominal reentry" button. How can you dare to take a day off! :rofl:

 

[Urwumpe]

I'm not an expert on the subject, but isn't this mode 'safer' than the lifting reentry?

Yes, it requires less hardware to work properly. It only needs maximal the roll rate gyro to avoid excessive rates and the RCS. And in theory, even that RGA could fail.

When the attitude reference in a lifting reentry is defect, the worst you can get is a lifting reentry with full negative lift - which no heat shield could compensate if it happens early.

Even during a late reentry, I already got from 2G to 12G in a capsule flight in Orbiter within a few seconds ( < 20 seconds from command to wrong bank attitude to 12G). The capsule would have survived this, though...

 

[simonpro]

I'm fairly sure that the BBC space correspondant thinks that the Soyuz capsule just contains a number of buttons marked "Big rocket go now", "Big rocket stop now" and, apparently, "Nice controlled reentry" (colored pink, probably) plus "Horrific uncontrolled death plunge" (with a skull and crossbones).
Alan Sugar is currently employed by the BBC, I suggest we unleash him upon their unfortunate space correspondant.

 

[Urwumpe]

I'm fairly sure that the BBC space correspondant thinks that the Soyuz capsule just contains a number of buttons marked "Big rocket go now", "Big rocket stop now" and, apparently, "Nice controlled reentry" (colored pink, probably) plus "Horrific uncontrolled death plunge" (with a skull and crossbones).
Alan Sugar is currently employed by the BBC, I suggest we unleash him upon their unfortunate space correspondant.

Actually Soyuz mostly has buttons labelled "On" and "Off". It's part of their command signal matrix architecture. But the only horrific uncontrolled death plunge button should be the "inhibit automatic propulsion module separation" button.

Don't know Alan Sugar, does he do Wrestling?

 

[Andy44]

I'm fairly sure that the BBC space correspondant thinks that the Soyuz capsule just contains a number of buttons marked "Big rocket go now", "Big rocket stop now" and, apparently, "Nice controlled reentry" (colored pink, probably) plus "Horrific uncontrolled death plunge" (with a skull and crossbones).
Alan Sugar is currently employed by the BBC, I suggest we unleash him upon their unfortunate space correspondant.

Doesn't the BBC think a proper rocket looks like a TARDIS?

 

[C3PO]

When the attitude reference in a lifting reentry is defect, the worst you can get is a lifting reentry with full negative lift - which no heat shield could compensate if it happens early.

I thought the worst case was if you get too much lift, and you start to gain altitude while slowing down. When you hit the second time, the angle is too steep for the shield.