Doug Vetter wrote:

And to think...the 480 has apparently been downgraded to a TSO 129 box...

Not true. The 480 is still approved for WAAS procedures - the SAIB just recommends a RAIM check and
a non-GPS alternate.

Note also that the press release includes a footnote saying the 430W is not approved for primary means
navigation. Just connecting the dots, it appears that the testing of the 430W revealed a marginal test
condition that was also applicable to the 480, and that resulted in both the 480 SAIB, and the need for
another software upgrade to the 430W to get the TSO limitation lifted and provide primary means WAAS
capability.

My guess is they took the TSO limitation to get the TSO completed, and allow the hardware retrofit to get
started. In the mean time they can work on the follow-on software update, which can be easily installed in
the field, separate from the hardware upgrade.

Mike