Lately, I have been talking about the SLC Airport: the international flights, possible flights, and even the longest flight.

Currently, the reigning champion of commercial aviation is Singapore Airlines Flight SQ 23, a staggering marathon from New York (JFK) to Singapore Changi (SIN) that keeps passengers airborne for 18 hours and 50 minutes, covering over 9,500 miles.

But what if you live in Utah? If you wanted to push a commercial aircraft to its absolute limits departing right out of Salt Lake City International Airport (SLC), how far could you actually go nonstop—and what happens if you add just one strategic stop to the itinerary?

The Current Limits: SLC’s Nonstop Reality

Because Salt Lake City sits landlocked in the Mountain West, planes departing from Utah hit geographical and fuel limitations much sooner than their coastal counterparts.

Furthermore, SLC’s high altitude (4,227 feet) means thinner air, requiring planes to use more runway and burn more fuel to lift off with a heavy fuel load.

Despite these hurdles, SLC punches well above its weight class as a major Delta Air Lines hub.

If you want to maximize your time in the air without a single connection, your absolute longest nonstop options are:

• Seoul, South Korea (ICN): The reigning heavyweight champion of SLC. This transpacific crossing keeps you in the air for roughly 13 hours and 5 minutes, passing over Alaska and the Pacific before dropping into Asia.
• The European Gateways: Flying nonstop to Paris (CDG), Amsterdam (AMS), or London (LHR) will keep you airborne for an impressive 10 to 10.5 hours.

To put that into perspective, to match the New York-to-Singapore world record using only nonstop flights from Utah, you would have to fly all the way to London, step off the plane, turn right around, and fly halfway back across the Atlantic Ocean before your clock hit 18 hours and 50 minutes!

The Wishlist: What is Physically Doable Nonstop?

If an airline decided to park an ultra-long-range aircraft like an Airbus A350 or a Boeing 787-9 at SLC tomorrow, what are the absolute longest nonstop flights physics would allow?

If we look at global destinations, aircraft could theoretically hit these boundaries nonstop from Utah:

• Hong Kong or Auckland, New Zealand: ~13.5 to 14 hours in the air.
• Sydney, Australia: ~14.5 to 15 hours in the air.
• Dubai, UAE: ~15.5 hours in the air.

The Hard Stop: What is Physically Impossible?

If you want to fly nonstop from SLC to South Africa (Johannesburg or Cape Town), you are out of luck. At nearly 10,000 miles, the flight time would soar past 20 hours. Between SLC’s high altitude, which restricts takeoff weights, and the sheer distance, a standard commercial plane would run out of fuel. It is one of the few places on Earth you physically cannot reach nonstop from Utah.

Maxing Out the Clock: The Power of One Strategic Stop

If you are willing to break your journey for a quick leg-stretch and a refill of jet fuel, adding just a single stop at one of America’s major mega-hubs completely unlocks the globe.

By leveraging a single connection at LAX, JFK, or ATL, you can comfortably replicate—and even beat—the 18-hour-and-50-minute airtime of the world’s longest flight. Here is how you can use Utah’s gateway hubs to maximize your flight time:

1. The Pacific Gateway: One Stop via LAX

Heading west out of Utah into Los Angeles International Airport (LAX) positions you perfectly for massive transpacific leaps.

• The Route: SLC to LAX to  Singapore (SIN) or Sydney (SYD)
• The Air Time: After a quick 2-hour hop to Southern California, you board a heavy-lifter to cross the Pacific. A connection to Singapore nets you roughly 19 total hours in the air, while a jump to Australia gives you a clean 17 hours of air time.

2. The Global Crossroads: One Stop via JFK

Connecting through New York’s John F. Kennedy International Airport (JFK) allows you to split your journey over the Atlantic or take a direct polar route down into South Asia.

• The Route: SLC to  JFK to New Delhi, India (DEL)
• The Air Time: You will spend about 4.5 hours flying coast-to-coast across the United States. Once at JFK, you can board a marathon 14.5-hour flight straight to India. Your total time physically suspended in the air? Right around 19 hours.

3. The Deep South Super-Hub: One Stop via ATL

Delta’s crown jewel hub is Hartsfield-Jackson Atlanta International Airport (ATL). Because Atlanta sits significantly closer to the equator and the Atlantic than Salt Lake City, it serves as the perfect launching pad for destinations deep in the Southern Hemisphere.

• The Route: SLC to ATL to Johannesburg, South Africa (JNB)
• The Air Time: You start with a 3.5-hour domestic flight to Georgia. From there, you board one of the longest over-ocean flights in Delta’s entire network: a massive, 16-hour and 40-minute push straight down the Atlantic to South Africa. Total time in the clouds totals a mind-boggling 20 hours and 10 minutes.

Final Thoughts

While Salt Lake City may not host the nonstop, 18-hour global marathons found along coastlines, its unique positioning as a heavy-hitting interior hub gives Utah travelers the best of both worlds. You can choose a highly efficient 13-hour nonstop flight straight into the heart of Asia, or, with just one single stop at a coastal gateway, you can comfortably spend a full 20 hours in the sky, bound for the literal ends of the Earth.

My question to you is

Where is your next marathon flight taking you?

Next Week

Boeing 777X

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