Well, one of Russia's two Sukhoi T-50 PAK FA stealth fighters had to abort a takeoff at the 2011 MAKS airshow outside Moscow today. Apparently, a problem with the right engine forced the pilot to cancel the takeoff following four days of successful demo flights by both PAK FA test jets at the show. I'm curious to know which of the jets suffered the engine malfunction. The second PAK FA, used to test the plane's mission systems, was grounded for months until just last week for unknown reasons.
It'll be interesting to see if Sukhoi can really get the jet into mass production by 2016.
Enjoy this video of, among other things, the PAK FA's (non-aborted) takeoff roll.