Every time she flies, Allison Dvaladze goes through her personal safety checklist.

Dvaladze travels frequently as the director of strategy for an international women's cancer program based at the University of Washington. She always books an aisle seat, and places a blanket on her lap before she buckles her seat belt. And when she sleeps, it’s with one eye open.

“I’m always aware of my surroundings,” she said. “I’m always aware of who is sitting next to me.”

It’s a strategy that Dvaladze has employed since April 2016, when — on an overnight Delta flight from Seattle to Amsterdam — the stranger seated beside her suddenly reached between her legs and grabbed her crotch, she said.

What happened to Dvaladze is not an isolated incident.

Sexual assaults on flights are increasing “at an alarming rate,” FBI Special Agent David Rodski told reporters last week. “We’re not sure why.”

The FBI investigated 63 reports of sexual assault on planes last year, a 66 percent increase from the 38 investigated in 2014, Rodski said. The spike may have been driven in part by more people reporting the crime, but the latest figure still likely represents just a fraction of such incidents, since assault victims often choose not to come forward. And even if they do, there's no regulatory agency that comprehensively tracks the reports.

In the latest incident to make the news, Massachusetts Gov. Charlie Baker's son, Andrew “A.J.” Baker, was accused last weekend of groping a female passenger during a JetBlue flight from Washington to Boston. Police are investigating but did not immediately charge Baker, who denies the allegation.

The victims aren’t just passengers, but flight attendants as well, according to a recent survey conducted for the Association of Flight Attendants-CWA union, which found that more than two-thirds of its members have experienced in-air sexual harassment.

“While much of the coverage of the #MeToo movement has focused on high-profile cases in the entertainment industry and politics, this survey underscores why AFA has long been pushing to eradicate sexism and harassment within our own industry,” Sara Nelson, the union's president, said in a news release. “The time when flight attendants were objectified in airline marketing and people joked about ‘coffee, tea or me’ needs to be permanently grounded.”

Some politicians are trying to solve the issue. The Stopping Assault While Flying Enforcement Act of 2017, which was sponsored by Sen. Robert Casey Jr., D-Pa., and supported by Sen. Patty Murray, D-Wash., and other Senate Democrats, would require all air carriers operating in U.S. skies to train flight personnel on how to respond to sexual assaults. Also, it would give the Department of Transportation the green light to establish a National In-Flight Sexual Assault Task Force that would create a “streamlined process for reporting incidents.”

“Airlines cannot always prevent this from happening,” said Dvaladze, who began researching and speaking out about airplane assaults after it happened to her. “But they can create a deterrent. If you know this is a crime and you will be held accountable, that will hopefully deter people from doing it.”

That message, Dvaladze said, could be delivered the same way flight attendants prep passengers for takeoff by showing them how to put on oxygen masks and life preservers.

“This is not a new issue,” she said. “Airlines were discussing this in 1998. The problem is that there is no good data."

Rodski said sexual assault on a plane is a federal crime and agreed that the FBI is only aware of some of the cases. He said most of the assaults happen on red-eye flights after the cabin lights are darkened — and after alcohol has been served.

Paul Hudson, president of Flyersrights.org, an airline consumer organization, said reporting an assault is not that easy.

“One of the biggest problems is there is a four- or five-step process to report the cases,” he said. “If you’re on a plane, you can’t call 911. You can report to the flight attendant who then has to report to the captain. Then the captain is supposed to report to the ground supervisors. Then it may or may not get to the FBI.”

Dvaladze said she immediately reported what happened to her to the Delta flight attendants — and it didn’t matter.

“They didn’t know what to do,” she said. “In fact, they asked me what I wanted to do. And then they told me to go back to my seat. I said, ‘Absolutely not, are you crazy?'”

Dvaladze said the flight attendants convinced another passenger to switch seats with her by offering him frequent flyer miles. She said a month after the incident, Delta responded to her formal complaint by offering her 10,000 SkyMiles “in hopes of easing some of the frustration and inconvenience you may have felt.”

“It was a totally inadequate response,” she said.

Dvaladze said Delta would not disclose the name of her alleged attacker, even though the airline had sold him a ticket. She sued Delta this year.

A Delta spokeswoman declined to comment on Dvaladze's case "due to pending litigation."

“Delta crews are trained to respond to a number of onboard passenger disruptions, and our crews treat all reports of harassment as serious as the safety of our customers and crews are our top priority,” the company said in a statement.

What happened to Dvaladze's attacker?

“When we landed in Amsterdam, he just walked off the plane,” she said.