A wheel fell off one of the Las Vegas Monorail trains early this month, forcing the entire system to shut down during a major convention and one of the busiest holiday weekends of the year.

After repairs and a major investigation, the system reopened six days later -- only to close again the next day when another small part fell off a train. As of Sept. 13, the system is still closed.

The first incident occurred early Sept. 1 when a 60-pound guidance wheel broke loose from a train and fell into a Harrahs parking lot. No one was injured and there was no damage caused to anything other than the systems' pride.

Trains had to stay in their stations for six days during an investigation into the cause. This threw a monkey wrench into the plans of the tens of thousands of Mens Apparel Guild of California (MAGIC) convention goers and Labor Day holiday vacationers who had hoped to use the monorail to get around the Strip.

Monorail officials laid the blame on an improperly installed wheel and a missed opportunity to solve the problem before it occurred. Operators of the system apparently ignored automated warnings of potential trouble that came in the night before the wheel fell off. Wheel systems on all trains were inspected, and similar problems were found on several of them.

All of those problems were reportedly fixed, and additional personnel have been added to the guidance system oversight team in an effort to, well, hear an alarm when it goes off, I suppose.

The system reopened Sept. 7, after an estimated loss of around $500,000 in revenue.

But then the losses and embarrassment continued the next day when a bolt on one of the trains broke and a two-pound chunk of metal fell off onto a live wire, causing a small electrical explosion (or a big electrical spark depending on whose version you want to believe). The metal piece then fell 20 feet to the street below, luckily missing people and cars.

The metal assembly in question is used to hold the driveshaft of the monorail in place. You may remember back in January an entire driveshaft fell out of one of the monorail trains onto a service lot during testing, delaying the debut of the system by several months. Whether the two issues are related is under investigation.

Regardless, the monorail line was shut down immediately and all the engineers who were brought out to fix the last problem were coming back to Las Vegas to look at this one.

The $650 million monorail system has been running for about two months and has had its share of bad press. I'm still confident the kinks will be worked out and the trains will eventually be a good thing for Las Vegas. Until then ... maybe its best if you don't stand directly under the tracks.