CCA From Hong Kong, joined Oct 2002, 872 posts, RR: 14
Reply 4, posted (12 years 3 weeks 4 hours ago) and read 3653 times:
Usually at low speed with high thrust and the right atmospheric conditions low pressure vortices form due to condensation, this one looks more like it's passed over a puddle of water which helps the process but gives a similar, but much more spectacular effect.
This is another way for the same sort of thing.
AApilot2b From United States of America, joined Nov 2000, 578 posts, RR: 1
Reply 5, posted (12 years 3 weeks 1 hour ago) and read 3562 times:
The answer by CCA says it all. I have seen this a lot with F-16s. They create a mini tornado in front of the aircraft (even at idle) it is most noticeable if their is moisture in the air. It is pretty cool to watch.
A330DAT From Belgium, joined Nov 2001, 469 posts, RR: 1
Reply 7, posted (12 years 2 weeks 6 days 20 hours ago) and read 3394 times:
Just like AApilot2b said. It's a mini tornado being formed with air being sucked into the engine.
Below here are pictures of 737's equipped with "pins" in front of their engines, which are there to avoid injestion (sucking up) of debris. Not all aircraft are equipped with this, of course. In this case they are used in rugged terrain of the high north where the risk of engine damage is greater. Also notice what looks like a ski on the forward landing gear. This also prevents debris (rocks, pebbles...) from damaging the aircraft.