Just like the Bottom of the green is VS1.

Big (yet common) misconception there.... VS1 is simply the stall speed in a
"Specified" condition. In MOST aircraft this is stall in a clean
configuration, but the definition of VS1 does not require it to be a stall
speed in the "Clean" configuration. It is entirely possible that the POH
may define VS1 as a stall with perhaps 10 deg flaps.... perhaps NEGATIVE
flaps (some aircraft can do that ya know for more efficient cruising),
perhaps VS1 can be clean with gear extended.... or it can be clean with gear
retracted.... whatever the manufactor specifies.


Still have no idea why structural crusing speed is shortened to Vno "no"
doesn't seem like an it fits.. unlike NE and FE and so forth. Kind of like
Va... how does "a" represent manuevering.... but it does. One of those
aviation things... if it all made sense it wouldn't be worth doing!
Perhaps they say "Normal Operating" because it reminds them where they
"Normally Operate" I've never flown a plane that cruises in the yellow
arc.... the ONLY time I've seen the yellow arc has been in descents... Fly
mainly Piper Archer/Arrow/Seminole... have about sixty hours in a C-172.
Not exactly speed deamons.