Summer 2021: last ever flying Lockheed S-3 Viking ASW carrier jet to be retired by NASA....

[Stratofreighter]

...as it is NASA, these days civilian registered N601NA,

I suppose this Lockheed Viking can now be considered "civil" by some?

https://www.thedrive.com/the-war-zone/4 ... the-sunset
/
https://www.avweb.com/aviation-news/nas ... 3b-viking/
/
https://www.nasa.gov/feature/glenn/2021 ... -its-fleet

The history of this particular Lockheed airframe:
https://www.avgeekery.com/nasa-601-the- ... t-vikings/

Today the last Viking built wears registration number N601NA and NASA tail number 601.
Since then the remaining “War Hoover” S-3B Vikings in Naval service have all been retired- the last of them in 2016.

N601NA is literally the very last S-3B Viking.
BuNo 160607/N601NA may be the only aircraft that was both the last one of its kind built and the last one of its kind to be airworthy.

[Bennie]

Aren't most NASA aircraft 'civil' in this respect?

[SquAdmin]

I believe all mil airframes that are in use with NASA are on loan and thereby still property of the armed services. Not entirely sure, so if someone could confirm...