Purists say it cheapens a military air show to have a private airline participate.
Either way, the Oct. 9 flyover seemed routine enough to most spectators as part of San Francisco's Fleet Week. Virgin America did a similar flyover during the 2008 Fleet Week. Virgin had a slightly different flight path.
Travel expert Chris McGinnis watched the Blue Angels show from a boat in San Francisco Bay. He knew the 747 was coming -- newspapers had reported its flyover a day before as part of their event coverage -- and was excited to see it.
"I did not have any issues with it," McGinnis said. "I thought it was a cool. I was in the cool camp. I knew it was coming.
"I loved it. I'm the kind of guy who goes to the airport to watch planes take off and land."
But others around him had some issues.
McGinnis recapped the flight in his blog post for the San Francisco Chronicle.
"I thought it looked pretty cool," he wrote. "But I heard some grumbling among the crowd I was with about it. When I posted some shots and video ... on my Facebook page, a minor scuffle broke out between some friends who liked it, others who said it reminded them of 9/11, and a vet who was appalled at the invasion of corporate sponsorship into a military show."
From there, the debate just took off.
Many commenters noted that United is a big employer in the Bay Area and was happy to see the airline participating.
Nothing New About Airline Flyovers
But aviation enthusiasts note that such flyovers happen at air shows all the time.
"To me, it just seems silly that people are getting upset that United did that," said David Parker Brown, founder of AirlineReporter.com. "I would hope this wouldn't scare away other airlines from doing publicity stunts."
In a statement, United said that the flyover was "well advertised in advance."
"Newspaper stories previewing the weekend noted that the United jet would fly closely over the Golden Gate Bridge," United noted.