UNIVERSAL KNOWLEDGE on Instagram: "The Instagram reel showcases a DIY "pickle jar pulse jet," a simple valveless engine using alcohol-soaked cotton ignited via a lid hole, producing pulsating blue flames and thrust through cyclic combustion and exhaust, as seen in the 20-second video. This homemade design mimics full-scale pulsejets like the WWII German V-1 "buzz bomb," which powered over 30,000 cruise missiles with similar intermittent ignition for efficient, low-cost propulsion, though noisier