USA 186 (2005-042A), the secondary West plane KH-11, is still in a non sun-synchronous orbit and hence still drifting westwards. It is drifting for over half a year now. The difference in RAAN with USA 245, the primary West plane KH-11, is now over 20 degrees (21.8 degrees on May 19th). I am very curious as to when the drifting will stop, if ever. If it continues to drift for many weeks to come, we should contemplate whether perhaps the satellite is "dead", i.e. has lost manoeuverability. Problem is that NW European observers temporarily have lost visibility of the satellite, due to the current short nights. Tracking all comes down now to observers in the US and southern Europe.
Meanwhile, Russell Eberst in Scotland recovered USA 224 (2011-002A), the primary East plane KH-11, on May 9th. It is in a 260 x 1006 km orbit, which means it has slightly lowered its apogee. Before the winter blackout it was in a 258 x 1023 km orbit. The difference in RAAN with USA 245, the primary West plane KH-11, is now 48.5 degrees.
My own first observation of USA 224 was in the night of May 16-17. The image below shows it crossing through Corona borealis:
click image to enlarge
USA 161 (2001-044A), the secondary East plane KH-11, has still not emerged out of the winter blackout. Meanwhile, USA 129 (1996-072A) has gone missing since April 24 (see a previous post). There is a good chance it has been de-orbitted.
The current KH-11 constellation now looks like this (where the current orbital configuration of USA 161, in red, is uncertain, and USA 129 left out as it is no longer in its old orbit, and presumed de-orbitted):
click images to enlarge
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