Some sources confuse the "An-990" with the An-70-900 proposal (a stretched military transport with 8 propfans). That project was real but never left the CAD stage. However, the "An-70-900" is frequently misread as "An-990" in poor photocopies of Russian industry magazines from 1998. This is likely the true origin of the myth.
Navigating the plane requires several unique considerations: antonov an 990
A staggering 870 feet (265 meters)—that’s 3x the wingspan of the real-life An-225! Max Weight: 6,000 Tonnes (13.2 Million lbs). Scale: Roughly 120 times the weight of a Boeing 737-100. Some sources confuse the "An-990" with the An-70-900