Question on RNAV departures

[gt2]

Since I fly an archaic plane that has not seen pax in at least a decade, I have little experience in RNAV stuff. My question is...I was looking at an RNAV departure (particularly the Thrasher Five at ATL) and saw the phrase "RNAV 1" under the notes. What does this mean? I'd never seen it before, and couldn't find it in the Jepp intro section.

 

[328dude]

RNAV 1 means that it requires a total system error of not more than 1 NM for 95% of the total flight time.

RNAV 2 means the same thing only 2 NM.

It has a lot to do with your TSO compliance on your unit. RNAV 1 is always used on SID's and STAR's. RNAV 2 is primarily used for enroute unless specified otherwise.

 

[gt2]

thanks

I apreciate the quick response.