At the website: http://wiki.openwrt.org/toh/ubiquiti/routerstation, the following step-by-step instructions are listed to reflash the Firmware. 

1. Under the most recent Backfire repository, under ar71xx, find the image named "openwrt-ar71xx-ubnt-rs-squashfs-factory.bin".
2. Boot the system in recovery mode by holding the reset switch until the RF LED lights up while powering on the device.
3. Upload the new firmware to the device through WAN port using TFTP on the default IP address, 192.168.1.20.

GNU/Linux: tftp 192.168.1.20 -m binary -c put openwrt-ar71xx-ubnt-rs-jffs2-factory.bin

Note the .bin image in (1.) above is not the same as the filename shown in the above GNU/Linux tftp command statement.  Which is the correct file?

Hardware:
Ubquiti Routerstation 10.3 Atheros AR7161,  3 wired ports,  3x miniPCI NIC slots

TIA

Bill