A-330 MRTT Tanker Grounded for Modifications

Needless to say, the Boeing rent-a-crowd is probably all over this, but really, this grounding is a normal part of a test program. (Paid Subscription Required)

Basically, they are installing updated plumbing, and setting up a remote station for the boom operator in the cockpit.

Earlier tests have been about verifying the airworthiness of the boom, which it passed in flying colors, with testing of the boom in use being done on a smaller A310 testbed.

The MRTT is almost identical to the KC-45 selected by the USAF.