While cargo volume is soaring at other local airports, it has suddenly and inexplicably taken a nose-dive at Burbank Airport.

For the first six months of the year, Burbank suffered a 16 percent drop in cargo volume, from 45.2 million pounds in the first half of 1999 to 38 million for the like period this year. And the drop was not confined to one or two carriers it is spread evenly among all major airlines and overnight delivery services.

Federal Express and United Parcel Service, for example, saw their cargo volumes drop by 19.4 percent and 17.5 percent, respectively, during the first six months of 2000. Alaska Airlines saw a 29.4 percent drop and United Airlines’ volume went down by 9.1 percent.

At the same time, the number of passengers at the airport has stayed pretty much flat from last year, and there has been no comparable decrease in the number of flights.

All this raises the question of why Burbank has fallen out of favor as a cargo airport, and airport officials threw up their hands last week when asked for an explanation.

“We don’t really have an answer that fits the facts,” said Victor Gill, a spokesman for the Burbank-Glendale-Pasadena Airport Authority. “It seems more than just normal market fluctuations because the overall volume of air cargo in Southern California has not come down.”

In fact, total cargo volume at LAX is up 9 percent for the first six months, and at Ontario International it’s up 9.1 percent.

While cargo volume is generally expressed as the aggregate of incoming and outgoing cargo, the volume of incoming cargo has increased dramatically at Ontario by 21 percent for this period, whereas incoming cargo at Burbank dropped 27.2 percent.

This suggests that Ontario may be receiving a lot of shipments that previously went to Burbank.

“That could be part of the explanation,” said Bob Godlewski, a spokesman for UPS in Atlanta. “We don’t break out our numbers for individual airports but our overall volume has gone up and we do have a hub at Ontario. It might very well be the case that we have been rerouting more incoming goods through Ontario.”

An additional factor that may be contributing to the decline of incoming cargo at Burbank could be the ongoing corporate exodus from downtown L.A., Gill said.

“We’ve traditionally been kind of a niche market and would get late-afternoon shipments for downtown corporate headquarters,” he said.