Wheel detaches from United Airlines plane amid takeoff in Los Angeles City Airport.

A United Airlines flight experienced a malfunction during takeoff from Los Angeles International Airport when one of its landing-gear wheels detached but was able to safely return to Denver with all passengers and crew unharmed. The incident is under investigation by the airline, which stated that they are working diligently to understand the cause.

The aircraft involved in this event is a nearly 30-year-old Boeing 757, carrying 174 passengers along with seven members of its crew. This model was retired from production by Boeing in 2004. A similar incident occurred earlier in March when another United flight experienced an issue mid-flight but also landed safely without injuries to any individuals on board.

United's recent series of events includes a separate occurrence where an emergency landing was made at the same Los Angeles airport due to hydraulic system difficulties, as well as another incident in which a flight from Houston veered off the taxiway during its approach. These incidents have raised concerns about aircraft safety and maintenance practices within the company's fleet.

This recent occurrence is not isolated; it follows several other aviation industry occurrences that have garnered attention, including an emergency landing after a United flight encountered engine flames in Houston and an Alaska Airlines incident wherein a door latching mechanism detached mid-flight from their Boeing 737 MAX.

The impact of these events extends beyond immediate safety concerns as they also influence the financial performance and operational efficiency of airlines, with United citing the April incident's effect on its first quarter earnings in a recent disclosure to shareholders.