ATV-4 set to lift the Station tomorrow
Details on tomorrow's planned reboost for the ISS – the final one in the ATV-4 mission – from ESA's Thomas Beck at ATV-CC.
The reboost on Thursday [24.10] is planned to generate a modest delta-V (change in speed) of about 0.6 m/sec and to use approximately 85 kg of fuel.
The corresponding small increase in ISS altitude should be on the order of a bit less than 2 kilometres. The back-up date for this reboost is Saturday, 26 October.
I will provide more up-to-date figures after reboost termination.
Today’s fuel transfer to ISS complete
Fuel tank for the ATV cargo carrier Credit/Copyright © 2007 David Monniaux. Via http://commons.wikimedia.org/wiki/File:ATV_propeller_fuel_tank_p1220787.jpg
Confirmation from ESA's Mission Director Marcus de Deus Silva received just after completion at 17:44 CEST today.
ATV propellant transfer (fuel and oxidiser) has just been completed successfully.
Best regards, Marcus de Deus Silva
ESA-ATV - MD on console
Marcus added in a subsequent update:
ATV-4 has just successfully transferred all its refuelling propellant to tanks in the Russian segment of the ISS. This propellant consists of liquid fuel and oxidiser, which is used by the ISS to boost its orbit and control its attitude.
As expected, the total length of the refuelling operation was about one and a half hours. However, the propellant transfer itself – that is the time taken for the liquid to flow through the pipes and connectors – only took about half an hour.
As announced earlier, the next refuelling system operation will be purging – to expel any residual propellant from the refuelling system piping.
Fuel usage on last night’s departure burn
Quick update via ESA's Lionel Ferra on ATV fuel usage last night. This leaves about 1386 kg on board.
Water flows, fuel burns and avoiding debris
CONTINUED -- Diary from a space project 3 May, Thursday, L+42
A continuation of Charlotte Beskow's 'Mission Diary' update from last week. PLUS: Read below for a great overview of the orbital debris situation – Ed.
Independently of what were were doing on the RICU, the crew took the opportunity last week to discharge some more water. Twenty two litres of Russian water was transferred to a Russian water container; a total of 88 litres have now been transferred.
How water transfer from ATV to Station appears in ATV-CC
Apart from the verbal reporting on the voice loops, we can monitor these transfers by looking at the pressure parameters of the ATV tanks. Another good indication that something is happening inside ATV is the ON / OFF status of the lights inside ATV.
As an aside, we note that each crew is different: some always turn the lights OFF when they leave, others leave at least one light ON all the time -- just like the rest of us!
Tanking ATV-3 today with 2049kg of rocket fuel
Preparing to load MMH Fuel onto ATV3. Credit: ESA/C. Beskow
This sent in this AM from (a sleepy) Charlotte Beskow in Kourou, where teams today are loading MMH (Monomethylhydrazine - 'hydrazine rocket fuel') on board ATV-3 - Ed.
Today I under-slept... I can blame it on the fact that we will begin MMH fuelling preparations at 06:00 - or on my deteriorating eyesight (I couldn't read the alarm clock very well and only realised my mistake as I glanced at the wall clock before leaving at 04:45!).
We did the inspection of the MMH fuel loading set-up yesterday evening. It is fairly straightforward and consists of a big storage tank (containing 2,900 kg of MMH), 2 filters, a loading panel, a bubble tank (to ensure that the loaded MMH is free of bubbles), piping to the ATV, a line to recover the gas that is expelled as the fuel enters the tank, a waste tank (two, to be exact) and a cold trap which liquefies the fuel vapours (easier and safer to transport).
The system is set up for closed-loop operation which means that in case something goes wrong, the loaded fuel can be emptied back into the Storage tank.
This short paragraph translates, of course, into a lot of hoses, valves and procedures to ensure that we load clean fuel in a safe manner. Just as with loading of Russian fuel (which we did last week) only the Scape-suited operators are actually in the clean room. The test conductor, quality control, safety officers and the ESA representatives are in a separate room following the operations via camera and radio.
In total we are loading a total of 2049 kg of MMH. This will be done in one continuous operation by 9 teams. Estimated duration 30 hours.
More photos below
ATV-3 fuelling gets underway
ATV Fuelling Area in Kourou, waiting for Edoardo Amaldi Credit: ESA/C. Beskow
ATV-3 launch -2 months: Day 141 of the Launch Campaign
The first New Year update from ESA’s Charlotte Beskow in Kourou. This post written 5 Jan – Ed.
Post-holiday work restarted at CSG in Kourou on Monday, 2 January.
The ATV teams are already in place and busy preparing for the next big step: fuelling. We have a lot of fuel to load!
- The fuel ATV needs for its journey to and from the ISS (ca 2200 kg)
- The propellant to be used by ATV while attached for ISS attitude control and reboost (ca 2500 kg)
- The fuel that will be transferred to the Russian segment of the ISS (ca 860 kg)
The preparation and loading of this fuel will keep us busy throughout the month of January.
Today some of us completed our safety training for working in the fuelling area. Even though we have all done this training before it is good to get a refresher. In case of problems, you need to react quickly. None are expected, but it is important to be prepared! The fuel is toxic and the operators will wear special suits to protect them. Luckily, I am not one of them.
At the moment the fuelling area is empty (apart from some loading equipment). This will change tomorrow morning (6 January) when we push ATV Edoardo Amaldi, from work area S5C down the corridor and into S5B.
Affaire a suivre, as they say...
Diary from a space project: Undocking – 14 days (reentry – 15 days)
A quick update from Charlotte Beskow at ATV-CC in Toulouse, France, explaining how the ATV fuel lines have been emptied in preparation for undocking.
Monday, 6 June - undocking minus 14 days, reentry minus 15 days
Between this morning and now (22:03 CEST), we have completed the purging of the refuelling lines; last refuelling of the ISS was done 17 and 18 May.
We could not purge on 19 May due to Shuttle Endeavour operations but we have to do it before 20 June in order to be able to undock safely. So, this was done today.
The lines are purged of fuel / oxidiser and then vacuumed. The whole operation is automatic and the most important steps 9there are four in all) take less than 10 min each - but it is a critical operation and we take time to prepare properly and to check progress during / after the operation, so in total the operation lasts about three orbits (4.5 hours).
Since ATV's refuelling system is a Russian design, a Russian expert is here at ATV-CC in Toulouse with us, ready to help in case of problems.
Our lead engineer on the ATV project team for refuelling is also from Russia and has worked in MCC-M (Mission Control Centre - Moscow) and our interface officer is fluent in Russian, so the team was well prepared for any eventuality. In the end, everything went smoothly (just like for ATV-1)!
That part of the team can now go home for some well-deserved rest. Our next planned refuelling is with ATV-3 in 2012.
That’s it for today but I’ll be back in the coming days with more information on the final part of the ATV-2 mission.
ATV Kepler tanking up
ATV-2 tanking up at Kourou, 10 January 2011
In anticipation of the vessel's upcoming launch, scheduled for 15 February, ATV Johannes Kepler is now being 'tanked up' with fuel at Europe's Spaceport in Kourou.
Of all the vessels that can deliver cargo to the ISS, ATV can deliver the largest quantity of fuel, up to 5.5 tonnes maximum.
With this fuel, ATV can regularly reboost the Station's orbit, which suffers a natural decay of 50 to 100 m each day (what goes up must come down - unless reboosted by ATV - Ed.) due to drag caused by traces of atmosphere at the ISS orbital altitude (roughly, 400km) .
The predecessor of Johannes Kepler, ATV-1 Jules Verne, conducted four reboots during its 5-month attached phase in 2008. All ATVs can also perform debris avoidance manoeuvres for the ISS.
Kepler also saves a portion of its fuel so that it can properly and safely perform its own de-orbit manoeuvre at the end of its mission, after undocking from the ISS .
via L’ATV Kepler fait le plein « Le blog de l'image satellite – CNES.