There is a very big problem at London's Heathrow Airport. Planes land but it sometimes takes hours of waiting in line before travelers are let in. 

On April 22, I arrived from New York City to complete chaos. It was a Sunday morning at around 6:30 a.m. and I was tired after a seven-hour flight.

A crush of humanity greeted me in the immigration hall. Lines didn't just wind around, they stretched back outside the waiting area down into unknown, never-before-seen corridors. Travelers wore looks of shock, horror and fury depending on how much time they had already logged waiting. 

There were people who had traveled long distances, already exhausting their patience during the journey, and others who had traveled just a short distance — Heathrow is less than a three-hour flight from Madrid, Paris, Frankfurt and other major European cities. Most of the latter group would end up spending more time in line as they did on a plane.

Long immigration lines are often a part of international travel, but rarely, if ever, like this. In the last several months, the system at Heathrow, with alarming regularity, has come undone. 

The problem is so grave that London’s mayor, the outspoken Boris Johnson, on Sunday wrote a letter to Theresa May, the secretary of the Home Office, the UK’s equivalent to the Department of Homeland Security.

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He did not mince his words. “It is quite clear that because of problems at the UK Border, London and the UK’s reputation as a welcoming city in which to do business or travel are at stake," Johnson said, according to the copy of the letter given to NBC News. 

Hanging over the debate is the London 2012 Olympics. If Heathrow is having a hard time coping with run-of-the-mill travel numbers — more than 69 million people moved through the airport in 2011 — what will officials do when a large portion of the estimated millions of people expected to descend on the city try to cram themselves through ahead of the Games?

UK border patrol says British citizens as well those from the European Union have a target waiting time of 25 minutes and foreign nationals will wait 45 minutes. But over the last few months there have been numerous delays well over those targets.

Over the weekend the head of UK's Border Force, Brian Moore, responded to complaints and seemed to dismiss the severity of the problem.

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"Despite what you are hearing for the moment we are doing a really, really good job at achieving [target waiting times]. We don’t always get it right and occasionally there are disruptions to passengers for lots of reasons,” he said on British television. 

For example, Moore said unpredictable “flight bunching” sometimes causes a deluge of passengers. At other times people “aren’t presented to the right immigration desk.”

However, in Monday's Daily Telegraph, there were reports that the Home Office was actively trying to cover up the problem.  Marc Owen, director of the UK Border Agency, contacted BAA, the company that operates Heathrow, and instructed them not to hand out leaflets directing complaints to the Border Agency, the Telegraph reported.

“The leaflet is not all right with us.  It is both inflammatory and likely to increase tensions in our arrival halls,” the newspaper quoted him as saying. 

BAA's press office declined to comment on the leaflets, but they did say this in a statement: “Immigration is a matter for the home office. Immigration waiting times during peak periods at Heathrow recently have been unacceptable.” The press agent then offered to give me the Home Office’s number — just in case I needed it.

In three months the world descends upon this city for the 2012 Summer Olympics. The Border Agency insists that staffing will be increased to handle the millions of people visiting the UK during that time.  Hopefully, it works. 

London’s image is on the line. It would be a real shame if it was tarnished before anyone even got through the door.

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