This return occurred just 32 minutes after the Boeing 737-700 , operating as Flight 2301, departed at 08:52 local time.
Flight Aware data showed the airplane left from Sacramento at 08:52 on Saturday local time and returned to Sacramento at 09:24 in the morning.
According to The Aviation Herald, the crew asked to level off at 4000 feet, saying they were looking at something, as the plane climbed out of Sacramento's runway 35L.
Approximately one minute after leveling off at 4000 feet, the crew reported that they had to head back to Sacramento due to a potential engine problem.
For passengers like Christine Buff, the ordeal was both unsettling and nerve-wracking. Buff, who was traveling from Sacramento to Raleigh, North Carolina, shared her experience with local television station KCRA 3, stating that the passengers could tell something was off shortly after takeoff.
"I smelled something weird. I mean, it wasn't like fresh air or anything. It smelled more like burning wires," she said. "As we're on the runway going super-fast, as you normally are for takeoff, that's when it went super loud. Boom."
Buff and another passenger who talked to KCRA 3 reported seeing what they believed to be flames coming from one of the engines.
Shortly after, the pilot informed passengers that they would return to Sacramento to allow mechanics to inspect the engine.
In a statement to Simple Flying, Southwest stated that the plane landed safely and passengers onboard were accommodated with a replacement aircraft.
"On Feb. 8, Southwest Airlines Flight 2301 made a non-emergency return to Sacramento International Airport to evaluate a possible engine issue. The aircraft landed uneventfully and taxied to the terminal, where Customers were accommodated aboard another aircraft to Denver. Southwest apologizes for any inconvenience. Nothing is more important to Southwest than the Safety of our Customers and Employees."
When asked about the engine issue by NBC Sacramento station, Southwest said there was nothing notable to report.
A replacement aircraft, a Boeing 737-700 registered N461WN, was sent by the airline to complete the remaining flight to Denver.
The journey was delayed by two hours and 10 minutes. The replacement aircraft N461WN was delivered to Southwest in May 2004 and is 20.8 years old.
Concerns over the safety of air travel have increased in the wake of a string of disturbing aviation accidents in recent weeks.
Concerns over the safety of air travel have increased in the wake of a string of disturbing aviation accidents in recent weeks, which has led to the most recent flight interruption.
The most notable event was on January 29, when an American Airlines passenger flight and a Black Hawk helicopter tragically collided near Ronald Reagan Washington National Airport and killed all 67 people on board.
This was the worst US aviation catastrophe since 2009.
"I thought at that point, this is it. We're going down and we're going to die," she said. "All I could think about was the plane that crashed into the helicopter. That's all I could think about this whole time."
