Main Engine Cut Off

The curious case of USA 276 is complicated by the sheer number of “coincidences” that appear to be involved. It is very easy (and dangerous) to descend into conspiracy theory and see everything as related. For example, consider the following summary list of “coincidences.” The quotation marks in this case are to indicate that it is open to debate whether this all is coincidental or not. Some or maybe all of them likely are true coincidences, but I leave it to the reader to decide:

1. The “coincidental” similarity of the USA 276 orbit to that of the ISS;

2. The launch moment “coincidentally” resulting in a very close encounter a mere month after launch;

3. The “coincidence” that the close encounter distance stayed just outside the ISS safety zone, with a small margin only, just enough to avoid safety issues;

4. The “coincidence” that the close approach happened around the approach and berthing of a US cargo ship, Dragon CRS-11.

But there is more:

5. When the launch of the Dragon CRS-11 was postponed for technical reasons, “coincidentally” it was decided that another US cargo ship, Cygnus OA-7, was suddenly to be unberthed from the ISS, a month ahead of the original schedule, on what would have been the original arrival date of CRS-11;

6. Ball Aerospace, the same company that built USA 276, “coincidentally” also built RAVEN, an instrument to monitor spacecraft approaching the ISS that was “coincidentally” attached to the outside of the ISS only a few months before the USA 276 close encounter;

7. As a commenter on my blog remarked, one of the US astronauts on board the ISS during the close approach, US Air Force Colonel Jack D. Fischer, “coincidentally” happens to have a military background in the space intelligence community (he served in the Space and Intelligence Capabilities Office), and his presence on the ISS was “coincidentally” bumped up to the current 51/52 ISS expedition. He originally was scheduled for the later 52/53 expedition: the change in his crew assigment was announced late November 2016.
That is quite a list of coincidences.

My own take on this all is that I think it is possible, but not certain, that the close approach was deliberate and meant to test space-based technologies to monitor grapplings and berthings of third-party objects. If this is correct, I tend to see the coincidence of the flyby with the originally planned Dragon arrival, but also the sudden undocking of Cygnus OA-7 when Dragon CRS-11 was postponed, as related to the technology demonstration. The relevance of the other coincidences is more conjectural: I tend to see the rescheduling of astronaut Jack Fischer as likely unrelated, for example.

Interesting. This will bring Dragon CRS-12 at the ISS while (on current orbit) USA 276 makes another close ISS approach. Is @SpaceX aware?

Difficult to say. Nominal close approach with current orbit is on or near Aug 18, but uncertainty at least a day. Also, maybe manoeuvres