United Boeing 757 Declares Mayday As Fuel Runs Low After Aborted Landing At San Francisco

Published Nov 1, 2026, 3:06 AM EST Luke has over a decade of experience as a travel writer and aviation analyst. As a passionate traveler based across the Middle East and Asia, Luke offers strong insights into the industry. Based in South East Asia. A United Airlines Boeing 757 declared a Mayday on Friday morning due to low fuel after aborting its landing at San Francisco International Airport (SFO) and going around. The aircraft — operating flight UA1023 from Boston Logan International Airport (BOS) — was on final approach to Runway 28R when it suddenly went around due to an unstable approach. Moments later, the flight crew declared "Mayday, Mayday, Mayday, fuel emergency," before climbing to 5,000 feet and reporting 5,200 lbs of fuel remaining. The flight, which had 97 people onboard, ultimately landed safely around 14 minutes after the go-around, with no injuries reported. United Flight 1023 Aborts Unstable Landing As Fuel Runs Low Credit: Robin Guess | Shutterstock The Boeing 757-200 (registration N19117) was operating the transcontinental service on the morning of Friday, October 30. Air traffic control (ATC) audio from Flight Follower shows that the controller cleared the aircraft to land on Runway 28R. ATC also warned the crew about wake turbulence from a Boeing 787 Dreamliner that had landed ahead of it, as well as a slight tailwind of five knots. The 757 then attempted to land at 11:11 AM local time — however, ADS-B data shows it started climbing at around 75 feet as the pilot initiated a go-around, later clarifying it was due to an unstable approach. The crew then declared a Mayday due to the fuel emergency and was cleared to land on Runway 28R for a second time, touching down safely at 11:24 AM. It is not clear whether the wind or wake turbulence from the preceding 787 played any part in the go-around. United Says No Emergency Was Declared Credit: Markus Mainka | Shutterstock Simple Flying contacted United Airlines for comment on this incident. A spokesperson responded that "the crew did not declare an emergency," while confirming that the flight had 91 passengers and six crew members onboard. The crew can be heard using the word "Mayday" when communicating with ATC, but the aircraft did not change its transponder squawk code. While a change to an emergency squawk code is standard protocol during emergencies, it is not necessarily required when the crew has already communicated the situation by radio. The 5,200 lbs of fuel remaining is close to the minimum threshold for a Boeing 757-200, although it is up to the discretion of the pilots whether to declare an emergency. Under FAA rules, US airlines on domestic flights must carry enough fuel to reach their destination and an alternate airport where required, plus a further 45 minutes of flying. The incident occurred just five days after another United flight reported critically low fuel levels — on Sunday, October 25, United flight 1854 from Grand Cayman (GCM) to Houston (IAH) declared an emergency after its right main landing gear failed to extend, with the pilots later reporting having just 10 to 12 minutes of fuel remaining. What Happens During Fuel Emergencies Credit: Jacek1708 | Shutterstock Fuel emergencies are among the most serious situations a crew can face, leaving pilots with limited time to reach an airport before fuel levels become critical. However, not every low-fuel situation is automatically an emergency. Pilots can first declare "minimum fuel" to alert ATC that they cannot handle any further delays to landing. If the situation becomes more urgent, pilots can declare an emergency using the "Mayday" call. This tells ATC that the aircraft requires immediate assistance, allowing controllers to prioritize its landing and deal with other flights accordingly. Importantly, a fuel emergency does not necessarily mean that the aircraft is moments away from running out of fuel. It means the crew has reached a point where its remaining fuel requires immediate attention and further delays cannot be accepted. In UA1023's case, the crew reported approximately 5,200 lbs of fuel remaining soon after the aborted landing, but it was able to land safely around 14 minutes later.