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The term Active Flow Control encompasses a surprisingly wide array of techniques [1]. Most of them are far more subtle that a Harrier like vectoring of exhaust

The term Active Flow Control encompasses a surprisingly wide array of techniques [1]. Most of them are far more subtle that a Harrier like vectoring of exhaust gas. Personally I'm a fan of "Electrically powered plasma actuators" which can use a high voltage AC source to alter how well the airflow sticks to the wing, and actively reduce drag. Here's some info I read about 2 decades ago on that approach[2] There were open source experiments with high voltage AC and lamp cord wire ("zip cord") in the year 2000.[3] The more time goes on, the more stuff I see as "leading edge" that I read about 20 years ago. ;-) [1] https://www.aerospacetestinginternational.com/features/is-active-flow-control-the-next-step-in-flight-controls.html https://www.aerospacetestinginternational.com/features/is-ac... [2] http://jlnlabs.online.fr/plasma/html/s_gdpthr1.htm http://jlnlabs.online.fr/plasma/html/s_gdpthr1.htm [3] http://jlnlabs.online.fr/plasma/html/s_gdp.htm http://jlnlabs.online.fr/plasma/html/s_gdp.htm

Steve44 3y ago
> Most of them are far more subtle that a Harrier like vectoring of exhaust gas. The Harrier has a number of bleed air reaction nozzles dotted around the aircraft so it can be controlled whilst hovering. The vectored thrust is just for the main "drive", these nozzles replace the control surfaces at hover speeds. https://xplanereviews.com/index.php?/forums/topic/965-aircraft-review-mcdonnell-douglas-harrier-av-8b-by-x-trident/ https://xplanereviews.com/index.php?/forums/topic/965-aircra... > For me the significant area was the flight "puffer" small reaction nozzles that are the most important and the most ingenious aspect of the Harrier. It is actually quite easy to support any aircraft on a downward thrust of gases, and even here with the clever engine mounted vector nozzles... the real trick was in actually controlling the aircraft in the air. The Harrier has a unique system of engine bleed that directs air to the various reaction nozzles...

Steve44 3y ago

> Most of them are far more subtle that a Harrier like vectoring of exhaust gas. The Harrier has a number of bleed air reaction nozzles dotted around the aircraft so it can be controlled whilst hovering. The vectored thrust is just for the main "drive", these nozzles replace the control surfaces at hover speeds. https://xplanereviews.com/index.php?/forums/topic/965-aircraft-review-mcdonnell-douglas-harrier-av-8b-by-x-trident/ https://xplanereviews.com/index.php?/forums/topic/965-aircra... > For me the significant area was the flight "puffer" small reaction nozzles that are the most important and the most ingenious aspect of the Harrier. It is actually quite easy to support any aircraft on a downward thrust of gases, and even here with the clever engine mounted vector nozzles... the real trick was in actually controlling the aircraft in the air. The Harrier has a unique system of engine bleed that directs air to the various reaction nozzles...