The video shows the flame motion following spark ignition in a turbulent methane jet. The flow conditions were: 30% air, 70% CH4, jet velocity 12.5m/s & 25m/s, framing rate 4200 fps, spark at r=0, z=40d (40 jet diameters; d=5mm). For details, see: S.F. Ahmed, E. Mastorakos, Spark ignition of lifted turbulent jet flames, Combustion and Flame 146 (2006) 215–231. doi:10.1016/j.combustflame.2006.03.007