Several hundred NetJets pilots are staging protests in seven cities over the lack of progress in contract talks.

NetJets, which sells partial ownership interests in business jets, is owned by Warren Buffett’s Berkshire Hathaway.

The pilots union says the concessions NetJets has been seeking since contract talks began in 2013 don’t fit with the picture of financial success company’s executives have described.

Thursday’s protests were planned at NetJets’ headquarters in Columbus, Ohio, and at airports the company serves in Dallas, Texas; Scottsdale, Arizona; Seattle, Washington; Teteboro, New Jersey; Van Nuys, California; and West Palm Beach, Florida.

NetJets CEO Adam Johnson says negotiators made remarkable progress over the summer and he’s confident an agreement will eventually be reached, but the two sides remain far apart on several key issues.

Photo Credit: Net Jets flights on the tarmac. Aero Icarus / Flickr