Newton’s third law says that forces come in equal and opposite pairs. This means that when air exerts lift on an airplane, the airplane also exerts a downward force on the air. This is clear in the image above, which shows a an A380 prototype launched through a wall of smoke. When the model passes, air is pushed downward. The finite size of the wings also generates dramatic wingtip vortices. The high pressure air on the underside of the wings tries to slip around the wingtip to the upper surface, where the local pressure is low. This generates the spiraling vortices, which can be a significant hazard to other nearby aircraft. They are also detrimental to the airplane’s lift because they reduce the downwash of air. Most commercial aircraft today mitigate these effects using winglets which weaken the vortices’ effects. (Image credit: Nat. Geo./BBC2)
For a period of 5 years starting in 1978 the US government issued a massive recall of the Fiat 850 for rust issues. Presumably those examples that weren’t pulled from the road in the recall likely fell victim to the rust-proofing, because today these are few to be found. The rear-mounted 843cc engine produced a whopping 49 horsepower, pushing the car to speeds of nearly 90mph.
Street-parked on Tiffany Street. San Francisco, CA.