I posted this comment on a less popular thread a few days ago: I had the luck of seeing this plane on approach to IAH airport while driving in Houston. For the first few minutes, it looked like a normal size plane, but felt too low and too slow. Then for the next few minutes, it kept getting bigger and bigger. Then I saw it had 6 engines. And a tail wing that seemed as large as a normal plane’s wingspan. I was lucky…
What you're describing matches my experience watching C-5M for the first time, heading in to land at what was Marine Corps Base Hawaii. I was out walking and watched one flying around the bay, turning in to land. Thought it was low and slow. I remember quite a feeling of cognitive dissonance, as subconscious parts of my brain were refusing to accept what my senses were really saying. Then this slowly dawning realisation no, it's bloody huge! I stopped in my tracks with my jaw dropping.
To some degree I still didn't believe it, until it had actually touched down at the strip in the distance, and I could see how it was in scale next to other planes and buildings.
I haven't seen the AN-225, guess I never will. Comparing specs I'm staggered.. I can't fathom what it would be like to see that one. C5 on left, AN-225 right:
Wingspan: 222' 9" 290'
Length: 247' 10" 275' 7"