The common query about whether skydiving causes the well-known “stomach drop” sensation touches on a fascinating intersection of physics and human physiology. This feeling, often associated with rollercoasters or elevators, is a reaction to a sudden change in the forces acting on the body. Understanding this experience requires looking at how the body perceives motion and how the atmosphere interacts with a falling object.
The Science Behind the Stomach Drop Sensation
The visceral feeling commonly described as the “stomach drop” is a physical response to a rapid decrease in the force supporting the body, occurring when a person is subjected to negative acceleration. This rapid reduction in the upward force counteracting gravity often results in a brief moment of near-weightlessness. It is not the stomach itself dropping, but the internal organs, known as the viscera, lagging slightly behind the skeletal structure as the body’s downward acceleration begins.
These internal organs, including the stomach and intestines, are relatively mobile and suspended within the abdominal cavity. When the body accelerates downward quickly, such as cresting the hill of a roller coaster, the support force beneath the body is suddenly reduced, and the organs momentarily float or lag. Nerves surrounding these organs detect this sudden change in pressure, sending a signal to the brain that registers as the disorienting, sinking sensation.
The vestibular system, housed in the inner ear, also contributes to the feeling by detecting changes in acceleration, not speed. A quick shift from a stable state to rapid downward motion effectively signals to the brain that the body is falling. This mechanism explains why driving a car over a steep hill or descending quickly in an elevator can produce the same brief, unsettling feeling.
Why Skydiving Feels Different: The Role of Terminal Velocity
The typical stomach-drop sensation is largely absent during the freefall portion of a skydive because the jumper quickly reaches terminal velocity. This is the maximum speed an object can achieve during a fall, occurring when the downward force of gravity is perfectly balanced by the upward force of air resistance (drag). At this point, the body ceases to accelerate, meaning the net acceleration approaches zero.
When a skydiver exits an aircraft, the plane is already moving horizontally at a high speed, often around 100 miles per hour. This existing momentum means the skydiver is not going from a near-standstill to a high speed, which is the condition that triggers the visceral drop on a roller coaster. The rapid transition from the aircraft’s speed to the body’s terminal velocity happens quickly.
The initial period of acceleration after exiting the plane lasts only a few seconds before air resistance builds up enough to stabilize the fall. This brief period is not enough to register the classic stomach-drop feeling. Once terminal velocity is reached, the body moves at a constant speed, which the inner ear and abdominal organs perceive as stable motion rather than an uncontrolled drop.
Sensory Experience During Freefall
The primary physical sensations during freefall are related to the intense interaction with the atmosphere. The skydiver’s body is essentially resting on a massive, high-pressure column of air. This resistance creates a feeling more akin to floating or flying rather than falling uncontrollably.
The experience is dominated by the powerful rush of wind, which can reach speeds of about 120 miles per hour. This wind generates a considerable amount of noise, making conversation impossible until the parachute opens. The force of the air against the body can be felt as a supportive pressure, much like sticking a hand out of a car window at highway speed.
This constant, stabilizing force of the wind allows skydivers to control their movement, shifting their body position to move across the sky. The overall sensation is one of intense sensory input and a unique feeling of stability. The entire freefall portion typically lasts between 30 and 60 seconds from an altitude of 14,000 feet, resulting in an exhilarating but smooth experience.