2001年11月19日 · Jets leave white trails, or contrails, in their wakes for the same reason you can sometimes see your breath. The hot, humid exhaust from jet engines mixes with the atmosphere, which at high...

2016年10月24日 · Smoke in jet engines is usually from unburnt or partially burnt fuel (or by water injection). Early jet engines used to create a lot of smoke due to these reasons (and due to lack of environmental regulations).

2018年3月12日 · The top answer of the suggested dupe says smoke is caused by water injection and inefficient engines not burning all the fuel. That explains what causes smoke but it doesn't explain why there is significant difference in visible smoke between takeoff and cruise, i.e. what changes to stop the conditions that cause smoke? $\endgroup$

2018年1月21日 · Smoke from unburnt or partially burnt fuel. This was prevalent in early jets and allowed to spot them from a distance - just follow the black line, at its tip is an aircraft. Smokeless combustor cans which allow more fuel-air mixing put an end to this. For more information I recommend the excellent web page contrailscience.

2024年9月12日 · Contrail clouds from passing jet planes streak the sky over the Utah desert. If you’ve ever looked up at a mostly blue sky and seen straight white lines criss-crossing the horizon, or watched a...

2015年7月30日 · Here are the reasons why many older jet engines are known to make more inky, acrid smoke, especially on takeoff, than newer models. The first type of jet engine to enter widespread commercial...

The primary sources of contrails are consistently jet powered aircraft, particularly those with multiple large high bypass ratio engines like those common on modern airliners and business aircraft. Because these aircraft are most efficient in the low humidity, cold air above 35,000 feet, airliners and business aircraft will continue to be the ...

2013年8月3日 · In the early development of jet engines, it was occasionally found that excessive amounts of coke or other carbonaceous deposits were formed in the combustion chamber. Sometimes a considerable amount of smoke was noted in the-exhaust gases. Excessive coke deposits may adversely affect jet-engine performance in several ways.

2017年1月21日 · As some aircraft fly through the sky, they leave trails of what appears to be smoke. Though do not be concerned, the trails are mostly condensation- hence the name “condensation trails”. As the...

2020年3月30日 · From small single-engine airplanes to large four-engine airplanes, all jet engine airplanes produce white smoke. It doesn’t stay in the sky forever. Rather, the white smoke will gradually dissipate over the course of a few hours.