From ATV Control Centre, Jean-Michel Bois' update on this morning's activities:
Two boosts this morning were performed with very high accuracy. At 07:42 and 08:30 UTC, decreasing ATV Albert Einstein's speed by 1.7 m/s.
The thrusters were ignited for 29 seconds, bringing Albert's orbit down to around 360km - around 50 km below the International Space Station's orbit.
The next set of manoeuvres is planned tomorrow 01 November at 18:27 and 19:13 UTC.
Final station reboost complete
Update from ESA's Thomas Beck at ATV-CC on today's reboost, the last planned reboost of the ATV-4 mission.
At 13:03 CEST, ATV-4 used two of its main engines, OCS1 and OCS3, to lift the ISS into a higher orbit. After a burn of 256.6 secs, the velocity of the orbital complex was changed by 0.62 m/sec. The manoeuvre burned 86.0kg of propellant.
This was the last scheduled reboost of ATV-4, which is set to undock from the ISS on Monday, 28 October 2013.
Update sent in last night from ESA's Mission Director Thomas Beck, at ATV-CC:
Today's reboost of the ISS was successful. At 19:35 GMT (21:35 CEST), ATV Albert Einstein used its two main engines (OCS1 and OCS3) to lift the ISS into a higher orbit. After a burn of 815 secs, the velocity of the orbital complex was increased by 1.95 m/sec. The amount of propellant burned for this manoeuvre was 271.6 kg.
The next reboost is planned for 23 October 2013, the final planned boost before ATV-4 departure from the ISS.
ATV reboost: ISS orbiting higher
On Sunday, 15 September, ATV-4 conducted a reboost for the ISS. Starting at 14:42 CEST, ATV Albert Einstein used two of its four main engines (OCS1 & OCS3) to lift the ISS into a slightly higher orbit.
After a burn of 205 secs, the velocity of the orbital complex was increased by 0.50 m/sec. The amount of propellant burned for this manoeuvre was 68.1 kg.
The next reboost using ATV is planned for 2 October 2013.
Thanks, Thomas Beck, at ATV-CC for the update!
ATV-4′s first ISS reboost complete
Quick update from ESA Mission Director Thomas Beck at ATV-CC Toulouse:
Today's ISS reboost by ATV-4 was successfully completed just before 07:45 CEST. The firing of Albert Einstein's Orbital Control System (OCS) engines No. 2 and 4 started at 07:35 CEST, lasted slightly less than 10 minutes and resulted in a 'delta-v' (change in Station velocity) of 1.45 m/sec. The manoeuvre consumed 199 kg of propellant.
Amaldi’s propulsion system is performing perfectly!
Yesterday, in a dual-burn reboost, ATV Edoardo Amaldi boosted the ISS, for the first time, into an orbit entirely above 400 km altitude. The burns took place at 11:45 and 15:17 CEST; the former ran for under 7 minutes while the latter ran for almost 35 minutes.
A Needed Boost - By astronaut Don Pettit 3 Apr 2012: Here is my attempt to capture a Station re-boost last weekend using the ATV (Automated Transfer Vehicle). Notice that as the burn progresses, a halo of exhaust accumulates that is visible when the thrusters fire for thrust corrections.
An engineering analysis of the European vessel's propulsion system performance showed the first burn achieved its planned propulsive push (that is, the planned increase in Station speed, measured in metres/second) within 1% of the target, while the second achieved an enviable 0.5%!
As a result, there will be no need to use the back-up boost slot available on 24 August.
Amaldi's propulsion is performing perfectly!
News from ATV-CC Toulouse: Today’s two-part ISS reboost continues
A quick update on today's dual-burn reboost from ATV-CC; ESA's Daniel Firre is on console at the Mission Director's position:
Today's reboost is split into two separate thruster ignitions. The purpose of the reboost is to set up the ISS phasing conditions for the Soyuz 30 landing in mid-September and Progress 49 accelerated rendezvous on 31 October.
Hot! Video showing how a 220N ATV thruster appears when firing. More details
The details of each part of the reboost are:
Time of ignition (TIG) 11:45:00 CEST. Burn duration (planned) is 6:24 min:secs providing a delta-V (change in velocity) of 0.9 m/s
TIG 15:17:00 GMT. Burn duration (planned) is 34:49 min:secs for a delta-V of 4.9 m/s
The total delta-V will be 5.8 m/s, which corresponds roughly to an increase in ISS altitude of 10 km.
Daniel Firre (right) in ESOC Main Control Room during Cryosat launch 8 April 2010
The propellant consumption for this reboost will be in the order of 780 kg.
The boost had to be split in two parts because the remaining propellant in one of the two tank systems of ATV-3 is not enough for the planned delta-V; therefore, it is necessary to switch tanks in between the two burns.
So far today, the first burn took place exactly as planned and ATV-CC has just performed the tank switching. Waiting now for the thruster temperatures to lower to the nominal value before starting the second burn.
... update after the second boost!
Cheers from Toulouse,
Update on ATV reboost anomaly
Editor's note: Yesterday's Station reboost resulted in an incomplete burn, which is explained below in an email received from ESA's Jean-Michel Bois, Head of Mission Operations at ATV-CC.
One ATV function is to maintain the ISS altitude by performing regular reboosts, raising the Station's altitude. This manoeuvre uses the ATV propulsion system, and is commanded by ISS software.
The regularly planned ISS reboost conducted by ATV-3 on 15 August stopped prematurely. The thruster burn was set to run for 1876 seconds to increase orbital speed by 4.4 m/s and raise the Station's orbit by 7.7 km to 414.4 km altitude.
The boost began as scheduled at 18:00 CEST using the No. 1 & 3 thrusters of the ATV vessel's Orbital Control System (OCS).
However, after achieving a 2.9 m/s speed increase, the boost was stopped by the ISS. A temperature alarm had been triggered by ATV on a thruster of the propulsion system (which was not used for this boost), but that is nevertheless permanently monitored.
This (correctly) generated an isolation of the suspect thruster from the rest of the vessel.
A signal was sent from ATV to the ISS to highlight this 'partial reconfiguration' (with ATV continuing to be available for the boost). But the ISS software stopped the boost, which was not the excepted reaction to this kind of anomaly.
Engineers at ATV-CC and their counterparts in Moscow and Houston are studying the cause of the initial ATV issue and of the unforeseen ISS reaction.
In order to give time to the ground experts to complete their investigation, it has been jointly agreed with the ISS control centres to perform the remainder of the yesterday's reboost during the next scheduled reboost slot, set for 22 August; this manoeuvre is compatible with the next vehicle (HTV and Soyuz) movements.
ATV remains in a safe configuration and is fully capable of performing any necessary operations, such as reboosting the Station or performing a debris avoidance manoeuvre if so commanded.
The ATV-3 Mission Manager, Massimo Cislaghi, said he was pleased with the skilled work of the joint ESA/CNES operations team in Toulouse together with the essential support of ESA Moscow in reacting to the issue and investigating the cause:
"While the results of the boost were 'outside routine business', the team reacted with skill to manage the issues that arose during the reboost, which are always delicate operations," said Massimo.
ATV-3 reboosts ISS: view from ‘on console’ at ATV-CC
ATV-3 conducted its 6th ISS reboost manoeuvre early this morning, and ESA Mission Director Adam Williams oversaw the activity at ATV-CC, Toulouse. He's sent in a detailed timeline of how it went -- giving a rare, 'on console' look behind the scenes of ATV operations.
ATV fires its thrusters to reboost ISS to higher orbit
With high solar activity, there is an increased risk of highly charged particles affecting ATV, at worst causing a reset of the Fault Tolerant Computer. If this occurred during the reboost it would terminate the boost before it was fully completed.
However, the Houston space weather forecast was more positive [than that of CNES, nominally responsible for space weather monitoring for ATV - Ed.], and the trilateral [i.e. Houston, Moscow, Toulouse - Ed.] conclusion was that the reboost could continue. Moscow and Houston both agreed it was better to attempt a reboost, and deal with the consequences of any underboost if and when it happened.
Wednesday, 18 July 2012 - All times Toulouse local - CEST
02:00 - All teams are on console preparing ATV for the reboost. Everything is calm.
03:40 - Successful transition of ATV to 'ISS Attitude Control' mode.
05:15 - Successful transition of ATV to 'ISS Reboost' mode.
05:16 - Start of reboost...
05:35 - Successful end of reboost and transition back to 'ISS Attitude Control' mode. Delta-V (change in velocity) achieved was around 2.8 m/s, which raised the ISS approximately 5 km.
06:15 - ATV back in 'Dormant' mode. Time for an early breakfast!
ATV-3 reboost update – Station orbits higher
Using its Orbit Correction System thrusters, ATV-3 performed a one-burn reboost of the ISS on 26 May at 02:10 CEST with a burn duration of 6 min, 17 sec. The burn achieved a 'delta-V' (change in orbital velocity) of 0.84 m/s (planned: 0.9 m/s), and increased the average Station altitude by 1.55 km (planned: 1.66 km).
Back in April, NASA astronaut Don Pettit, Expedition 30 flight engineer, captured this video of engines of the Automated Transfer Vehicle being fired to reboost the International Space Station. Credit: NASA
After the burn, the ISS was orbiting at 399.0 km average altitude, with 407.5 km apogee height and 390.6 km perigee height. The reboost was a slight underburn, providing about 7% less than expected delta-V and altitude gain.
This reboost -- together with the next one in June -- will set up orbit phasing for Soyuz 29S departure and landing, set for 1 July (the flight that will bring astronaut André Kuipers back home -- Ed.).
Times in UTC
6/05 - ATV-4 moves to the BAF for final preparations
8/05 - ESA Operations Readiness Review
20/05 - Late-cargo loading
31/05 - Launch Readiness Review
03/06 - IMMT GO/NO-GO for launch & docking
05/06 - Lift-off Arianespace VA213 23:52 CEST
15/06 - Docking 15:46 CEST
28/10 - Undocking 9:55 CET
2/11 - Reentry 13:05 CET All future dates subject to change