The T-50 or PAK FA aborted its demonstration flight at Zhukovskiy today when its right engine malfunctioned as it started down the runway. The pilot stopped the flight, deploying his brake chutes. The aircraft was traveling about 100 kmph when the malfunction occurred. The cause is being investigated.
Here’s RIA Novosti and other video of what occurred.
Kommersant reports its sources say the problem was a malfunction in the power plant’s automatic controls which allowed an uncontrolled supply of fuel to the engine. The incident could have had more serious consequences if the aircraft had actually taken off.
Russian Defense Policy 