Application Story

So, when Dr. Anne Jefferson’s underwater temperature loggers were blown up by a Minneapolis-St. Paul airport bomb squad, she hoped she would still be able to recover the five months' worth of data stored on them. And amazingly, she did.

Jefferson, a research associate studying hydrology in the Department of Geosciences at Oregon State University, had been using the devices to collect water temperature data in stream channels along the Mississippi River. Over the Thanksgiving weekend, she put the data loggers in the trunk of a rental car she had been using during the holiday break. She and her husband spent the holiday with family, and forgot to look in the trunk when they returned the car to the airport. By the time they arrived in Oregon and found federal agents waiting for them at the gate, the damage was already done.

A rental car company employee had been suspicious of the five, one-foot lengths of PVC pipe filled with gravel that he found in the car’s trunk. The pipes each contained three battery-powered underwater temperature-monitoring devices, called TidbiTs, which are slightly larger than bottle caps and have blinking LED lights.

The employee called the airport police, who in turn called the FBI, who eventually brought in a bomb squad.

When bomb-sniffing dogs found nothing, the squad removed the pipes from the trunk and used a high-pressure stream of water to “detonate” them. Nothing exploded, but the pipes were reduced to bits of plastic pipe and gravel.

After confirming her story with airport officials in Oregon, Jefferson said, “We drove the two hours from the airport to Corvallis, and there was a message waiting from the Minneapolis airport saying that some of the loggers were still intact.” The message wasn’t specific, but did mention that some of the devices’ green lights were still blinking.

Massachusetts-based Onset, which manufacturers the TidbiT loggers, caught wind of the story. According to Linda Cain, customer service manager, “We were able to contact Dr. Jefferson and let her know that we would like to try to retrieve the data from the loggers."

Two long weeks after the incident, Jefferson finally received all the loggers in a sealed police evidence bag.

Of the 15 battered devices, Jefferson was able to download data from all but a few. She sent the remaining two loggers to Onset, where engineers were able to recover the rest of the data.

Having this temperature data is a tremendous relief. “The data is the study, the basis for my postdoctoral research,” said Jefferson, “and without it, there was going to be a problem.” It wasn’t only Jefferson’s research at stake; scientists from several other universities are also participating in the project.

According to Onset’s Cain, the data likely survived because of the nature of the loggers. The TidbiTs are designed to be submerged underwater and to withstand rough conditions. The data recorded by the device is stored electronically in EEPROM, which unlike RAM, retains data even when the power supply is cut off.

Overall, no great harm was done, though Jefferson hasn’t tried to fly anywhere or rent a car since the incident. “We’re probably on their blacklist,” she said.