(CNN) -- A harrowing United Airlines flight Friday over the Pacific Ocean was forced to land on remote Midway Island because of what an FAA official said was an electrical odor on board.
The United Airlines plane, carrying 335 passengers and 13 crew on a Boeing 777, was flying from Honolulu to Guam when it was forced to land and spend seven hours on the Pacific atoll, said United spokeswoman Mary Clark. A replacement aircraft later carried everyone back to Hawaii on Friday, she said.
When explicitly asked Saturday whether the disturbing smell was smoke or something burning, Clark described the incident as an odor in the cabin.
A passenger, Karen von Merveldt-Guevara of Sedona, Arizona, said the pilot spoke of smoke and failure to the radar and other systems.
"The captain said there was smoke in the cockpit and the radar failed and other electronic systems were failing, so they had to land. I think they landed old-school. They did an amazing job to get there safely," Merveldt-Guevara said.
"At one point there was one drop of about 40 feet. After that turbulence, it got really silent. I thought everybody was praying, and we were coming in on the wings of faith. We were all praying," Merveldt-Guevara told CNN.
She said an odor emanated even before the plane took off. But the jet took flight any way before being diverted to Midway Island, a U.S. territory known as home to a World War II battle.
United is now investigating the plane, a Boeing 777. The new jetliner is one of the most sophisticated in aviation, Clark said Saturday.
United couldn't comment on further details, such as the purported radar failure, because its investigation is ongoing, Clark said.
Passengers: 'They should not have let us go'
Von-Merveldt said that passengers were told before the flight began that there was an odor in the cockpit.
Some people left the plane, but Merveldt-Guevara decided not to because she was with 25 people traveling together to a big family gathering in Guam.
"I'm just digesting it," she said Sunday in a telephone interview. "I think they should not have let us go from the plane from Honolulu. They told us they had a problem with a smell in the cockpit.
"We had 25 family members on board, and that made me think it was OK to stay," she added.
After all, she thought, her airplane ticket was a last-minute gift given to her a week earlier. "I thought this was godsend, this was meant to be. I was thinking this can't go wrong!" she said.
In fact, the flight takeoff was delayed in Honolulu for three hours, during which the plane sat on the tarmac, she said. "Then they let us go, and I thought it didn't feel right, but hey," she said.
But during the flight while everyone was asleep, Merveldt-Guevara overheard a conversation of a passenger with a flight attendant who said the plane was returning to Honolulu.
"When more people woke up, they made an announcement. I could understand they didn't want mutiny. First we thought it was of a storm hitting Guam. Then the smell got worse in the cabin, and I started to gag because of the smell of chemicals. The attendants were busy. In between they would communicate saying they were busy in the cockpit trying to figure things out," Merveldt-Guevara said.
On Midway Island
A video shows people fanning themselves with leafs of paper inside the cabin, apparently after the plane landed.
In the video, a voice on the intercom tells the passengers: "Midway is not an island that has hotels and things. It's just a diversion airport. What they're offering is they have gymnasium here that you can all go to if you like and they have chairs and things. We can put you there until we figure out what exactly is going on. They will open up their stores so you can get something to eat."
The video then displays passengers getting off the plane and walking the tarmac in the middle of the night.
Inside the gym, passengers sat on chairs or rested on the floor.
At the end of the video, the passengers cheered when addressed by a man in the top bleachers. Apparently, they were about to get off the island.
A new flight, 2105, flew the passengers to Guam, where they landed Saturday, Clark said.
FAA spokesman Allen Kenitzer described the odor aboard the plane as an "electrical smell" in the cabin or cockpit.
On Sunday, Merveldt-Guevara expressed relief that the journey was over.
"I thought let's just be grateful. Let's savor the moment," she said.
But she said her luggage still hadn't arrived in Guam.
CNN's Carma Hassan contributed to this report.