Three hundred travelers started the summer with an airplane nightmare they will not soon forget.



Hundreds of Newark-bound passengers sat for four hours on a tarmac in a stifling cabin after bad weather diverted their flight from London in Connecticut and union regulations grounded it there.



To make matters worse, passengers said, the plane's generators shut down for the second time, leaving them with no air conditioning and sweltering temperatures that reached 100 degrees.



Some people on the inauspicious Virgin Atlantic flight fainted from the heat, said Andrew Porwancher, of Princeton, N.J. One passenger was taken to a hospital, but airline officials said there is no evidence to link this with the flight.



"It was like four hours on the ground without any air conditioning. It was crazy. Just crazy,'' passenger Beth Willan told CNN. "There were babies on the plane. And we are in dark and hot. You try to be patient but people were yelling and screaming.''



Even before the flight left Heathrow Airport, there were problems. The generators were not working, so neither was the air conditioning system, passengers said. The flight was supposed to leave at 5:33 p.m., London time. Two hours later, with the plane fixed, the flight took off for Newark.



But problems arose again because of storms in the New York area on Tuesday night. The airline needed to divert the plane. With no option to land at JFK, it landed at Connecticut's Bradley Airport, the company said.



When the plane, carrying 300 passengers and 14 crew, landed on the tarmac, the generators broke for the second time, passengers said. With no fresh air coming in, temperatures reached a baking 100 degrees, they said.



For four hours, they sat on the plane, sweating, frustrated and tired. During the ordeal, pilots exceeded their maximum flight time and the plane had to stay grounded so after all that, the passengers still couldn't reach their Newark destination.



Passengers were eventually brought into a terminal, where they waited at least two more hours for their luggage and instructions on how they would eventually get to Newark.



Virgin Atlantic officials said Bradley Airport is not equipped to deal with international arrivals, so Virgin Atlantic had to wait for U.S. Immigration and Customs to arrive to process the passengers.



According to airport spokesman John Wallace, airport managers tried to find motel rooms for the stranded passengers but because of the golf tournament there was no room in the inn.



The flight was scheduled to reach Newark at 9:10 p.m. on Tuesday. Nearly 12 hours later, at about 8:30 a.m. Wednesday, passengers finally began boarding buses en route to Newark Airport.



Peter Blok, of Philadelphia, called the trip “hell on wheels.”



The airline apologized for the frustration and inconvenience the delays caused for the passengers.



“The safety and welfare of our passengers and crew is of paramount importance,” Virgin Atlantic said in a written statement. "Virgin Atlantic would like to thank passengers for their patience and apologise for any inconvenience cause. All passengers are now being transported to Newark by bus."



"It was a situation that was beyond our control,'' Janine Doy, a Virgin spokeswoman in London, told the Associated Press. "There were weather conditions. ... Bradley had to get customs and immigration to the airport.''



A new federal rule on flights stuck on runways went into effect in April and bans U.S. carriers from making passengers wait on planes for longer than three hours. But because the London-to-Newark flight was international, it isn't eligible for a fine under the tarmac delay rule.



Doy said she was checking into the passengers' reports of the plane not having air conditioning while stalled. She said the planes have water fountains aboard, but she wasn't sure if any food was left over after the in-flight meals had been served.



The delays frustrated not only the passengers desperately waiting to get off the Virgin Atlantic plane in Connecticut, but those waiting to get out of Newark on the airline as well.



Eva Shah may not even make her own wedding. Shah was supposed to fly Virgin Atlantic to Mumbai, but the Newark flight she needed to take to connect in Heathrow to complete the trip to India has been delayed 23 hours, her future brother-in-law, Justin Holmes, told NBCNewYork.



Holmes said the airline will only offer Shah a refund and will not transfer her to a more expensive flight.



The airline couldn't immediately be reached for comment on that matter.



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