New J-20 airframe pictured conducting high speed taxi tests

Scuttlebutt from Chengdu has been that J-20 2002 carried out high speed taxi test(s) last week, and as usual the Chinese spotting community have been out in force bringing us photos/video of the event. We've decided to save this post for when the first higher resolution photos started appearing, and true to form, we've not been disappointed, with a number of good photos appearing at various internet portals the past couple of days. There are quite a few interesting takeaways from the photos, which we will now look at (click on images below for higher resolution):

J-20 2002 during it's taxi test. Can't be long before this second airframe makes it's first flight.

J-20s 2001 and 2002 sit side by side. You can just about make out subtle differences between the radome shapes of the two aircraft in this view.

2 very good photos of J-20 2001 and 2002 compared from virtually similar angles. You can see how subtle the differences between shapes of the nose of both aircraft are. Of course the more obvious difference would be the location of the flight test instrumentation probes, with that on 2001 being offset to starboard and just above the tip of the radome, while 2002 has it's probe placed on the tip of it's nose. David Ceniotti over at The Aviationist believes that it could also be a sign of a different kind of radar, possibly an active electronically scanned array (AESA) fitted inside the new radome. However we reckon the redesign might be due to possible issues that cropped out (Aerodynamic? Or maybe low-observability?) during flight testing of the first prototype over the past seventeen months. Somehow, we wouldn't hold our collective breaths for answers on that one...

J-20 2001 lands after another flight. Purported taken in mid-April 2012, it is interesting to note that the aircraft has no flight test instrumentation probe fitted on the nose on this occasion.

A study of the main landing gear of the J-20. You can just about make out what appear to be weapons bays on the underside of the fuselage just in front of the main landing gear. The bays seem to be quite large (or at least long); which together with the seeming low level of rear-aspect stealth in the design, has led to speculation that the J-20 may be a first strike cruise missile carrier, designed to use its frontal aspect stealth to approach the target undetected, launch it's missiles and make a high speed getaway.