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:

  1. 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
  2. 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

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,

— Daniel