There are 6 Robinson R44 ASTRO aircraft on the U.S. registry that TailWiki has a page for. Every one is built from the public FAA record — year, serial, engine, home base, and registration history — and owners and pilots add photos, trips, and stories on top. The ones listed here were built between 1994 and 1999.
N18FH
1999 Robinson Helicopter Company R44 ASTRO
Auburn, IN
N680PM
1999 Robinson Helicopter Company R44 ASTRO
Knoxville, IA
N171WC
1997 Robinson Helicopter Company R44 ASTRO
Flora, IL
N128KR
1994 Robinson Helicopter Company R44 ASTRO
Skidmore, TX
N144FL
Robinson Helicopter Company R44 ASTRO
Indiantown, FL
N300MK
Robinson Helicopter Company R44 ASTRO
Kahuku, HI