We use the word “thrust” for the force that drives the airplane forward against air resistance. Because the word applies equally to all kinds of propulsion, comparisons of the properties of jets and props may include some statement to the effect that props produce their thrust by accelerating a mass of air backward.
Why Jets Fly High and Fast
Peter Garrison explains how jets produce thrust and recips produce torque.
Key Takeaways:
- Jet engines generate thrust internally by accelerating exhaust gases, becoming more efficient at higher altitudes and speeds; in contrast, propeller engines generate thrust by accelerating ambient air and lose efficiency as air density decreases with altitude and speed.
- Computer simulations reveal that a blunt-nosed body with a *rounded* leading edge, followed by a streamlined tail, can achieve significantly lower drag than a traditional bullet-shaped nose, influencing design choices from radial engines to vehicle aerodynamics.
- For optimal low-drag designs at subsonic speeds, gently tapering tails are more crucial than long, swoopy noses, and while airfoil shapes are best for enclosing volume, a blunt nose with a streamlined afterbody can be slightly superior for fairing objects with a specific cross-section due to reduced skin friction.
Key takeaways sponsored by Aviator Pro | Start Your Training ->
See a mistake? Contact us.
