Question General Spaceflight Q&A

[FordPrefect]

In the actual Shuttle coordinates, a +Z translation is downwards, and a +X translation is forward.

Are you manually entering orbit or allowing the Shuttle Fleet autopilot to fly the ascent? The reason I ask is that the separation burn at ET sep should put you well above the tank so that by OMS2 the tank is below and in front of you.

Hello David, thanks for chiming in. Well, I'll let the autopilot do all the work of the ascent. The only thing I did is to fire translational RCS thrusters "downwards" during the programmed ET sep burn of your autopilot, to counter the upwards RCS thrust, only because I have the impression that the ET sep burn in the real world has a lot lower delta-V than your AP performs? Please excuse me, if I am totally wrong with that observation.
Maybe I should increase the delta-V on my +X burn to prevent the situation described above?

 

[IronRain]

Today NASAKennedy tweeted:

Shuttle Discovery: Technicians will remove a thruster on the spacecraft's nose landing gear today.

What kind of thruster is on the nose landing gear?

 

[DaveS]

Today NASAKennedy tweeted:



What kind of thruster is on the nose landing gear?

It assists the NLG deploy mechanism.

 

[Urwumpe]

What kind of thruster is on the nose landing gear?

Think of a piston that is extended by a small pyrotechnic gas generator. Such things are also called thrusters.

 

[agentgonzo]

Ah shoot, sorry for that. Of course it is translational... :facepalm:

And sorry, I was thinking with the Apollo spacecraft coordinate system.
What I meant with translational actually is, they do not perform a burn "sideways", in order to get out of the orbital path of the ET!?

Correct. I think you were confusing the word 'translational' with 'lateral'

---------- Post added at 13:35 ---------- Previous post was at 13:33 ----------

Sounds like there is some confusion between the two different co-ordinate systems used in Orbiter and the shuttle world. They are different (left handed and right handed I believe?)

a +X translation (into the VV) would mean that the shuttle is slightly higher and slightly slower than the ET which would make sense. When STS-134 was originally going to launch two weeks ago we in the UK were looking forward to seeing the ET and Shuttle fly overhead. The ET would have been just slightly in front of the shuttle.

Gary, I looked at this and it still wouldn't have been visible. It would have passed over Kent at something like 20:15 (or was it 19:45, or 20:00) and would unfortunately still be light in the sky. If you knew *exactly* where it was in the sky, you'd probably still have been able to see it, but it would have been VERY hard work. As it was, it was even harder as it was still in Florida, and thus under the horizon.

---------- Post added at 13:39 ---------- Previous post was at 13:35 ----------

Assuming the plan goes ahead and weather is good, roughly what time will the landing opportunities at KSC be on the 1st?

 

[garyw]

Assuming the plan goes ahead and weather is good, roughly what time will the landing opportunities at KSC be on the 1st?

Hard to say this early in the mission but NASA are looking at 1st June, 02:32 EDT

Now for a question for me. Yesterday Flight aware showed an Antonov AN124 flying from EBOS (Ostend Bruges) to KTTS (NASA Landing field). Any thoughts as to what this Antonov is carrying?

 

[agentgonzo]

Yesterday Flight aware showed an Antonov AN124 flying from EBOS (Ostend Bruges) to KTTS (NASA Landing field). Any thoughts as to what this Antonov is carrying?

Cheese

 

[diogom]

Hard to say this early in the mission but NASA are looking at 1st June, 02:32 EDT

Wait, 02:32 as in 02:32 a.m.?

 

[Urwumpe]

Now for a question for me. Yesterday Flight aware showed an Antonov AN124 flying from EBOS (Ostend Bruges) to KTTS (NASA Landing field). Any thoughts as to what this Antonov is carrying?

Lets look over the next Atlas V launches...

Juno ... no significant European contribution (sorry Italy).

Falcon 9... nothing European

Shuttle... nothing European

Maybe they are flying a payload out of the USA?

Also can't find much about it on the homepage of the carrier:

http://www.volga-dnepr.com/

Ok, had ignored that there is a second carrier that uses An-124 currently:

http://www.polet.ru/en/cargo/news

But nothing to the USA in their news.

 

[DaveS]

The AN124 is used to ship Atlas V stages to CCAFS.

 

[Urwumpe]

The AN124 is used to ship Atlas V stages to CCAFS.

From Ostend, Belgium? :blink:

 

[DaveS]

From Ostend, Belgium? :blink:

No, from Denver, CO.

 

[agentgonzo]

... from EBOS (Ostend Bruges) ...

No, from Denver, CO.

What? EBOS is the ID for Oostende airport in Belgium.

 

[garyw]

Wait, 02:32 as in 02:32 a.m.?

Erm yes otherwise I'd have put 14:32 :lol:

This is a preliminary set of data from NASA so it may well change depending on burns, wave-offs and such like.

---------- Post added at 12:00 ---------- Previous post was at 11:59 ----------

What? EBOS is the ID for Oostende airport in Belgium.

Yes and that was listed as the originating airport. After landing at KTTS the AN124 left a few hours later and went to Andrews AfB.

Also, it was listed as belonging to volga-dnepr. You can see the details on flightaware here.

 

[Urwumpe]

Ostend-Brugge is the closest international airport to the ESTEC, maybe they transported something from there to KSC.

 

[David413]

Hello David, thanks for chiming in. Well, I'll let the autopilot do all the work of the ascent. The only thing I did is to fire translational RCS thrusters "downwards" during the programmed ET sep burn of your autopilot, to counter the upwards RCS thrust, only because I have the impression that the ET sep burn in the real world has a lot lower delta-V than your AP performs? Please excuse me, if I am totally wrong with that observation.
Maybe I should increase the delta-V on my +X burn to prevent the situation described above?

The duration of the burn is based upon documentation I have for the orbiter as is the isp of the thrusters. I'll take a look and see if the translation burns have changed post-Columbia in order to allow the +X burn and manuever to get better pictures of the tank. As to your original question about translating "side-ways", I'm not aware of any movement in that direction...

Dave

---------- Post added at 19:37 ---------- Previous post was at 17:18 ----------

Wait, 02:32 as in 02:32 a.m.?

If it's any help, it will be 06:32 GMT. :lol:

 

[Krikkit]

I know, not ISS but I didn't see a Q/A for for Soyuz

What are these things for

 

[tl8]

I believe they stabilise(Aerodynamically) the module in the event of an abort.

 

[Wood]

Couple of silly questions:
Why does the station fly backwards while the shuttle is docked? And why do the Russians and Americans use tethers in a different way during EVA, with a pair of alternating short tethers vs a long lifeline type arrangement?

Thanks.

 

[garyw]

The space station flies -XVV so that the heatsheild of the shuttle is protected from MMOD impacts. Several times windows or radiators have been damaged by MMOD and the decision was made that this is preferable to the rather fragile tiles.