Tailspin (noun)

1. A sudden downward spiral of a aircraft in flight.
2. A rapid and uncontrolled descent or decline.

Origin:

Tail + spin.

Examples:

1. The plane went into a tailspin and crashed.
2. The company's profits went into a tailspin.
3. The stock market was in a tailspin.
4. The economy went into a tailspin after the pandemic.
5. The tailspin caused the plane to lose altitude rapidly.