Though we often think of planes as extremely safe, protected, and highly regulated spaces, there are several factors that sexual predators on planes often utilize to their advantage. "We have people crammed together in closer spaces than ever before," Nelson tells Bustle. Airline seats have become smaller (average seat size has dropped from 18 inches across to 17 inches over the past decade), meaning flights contain more passengers in closer quarters than in the past — which can provide cover for abuse and assault. "You would think that with more people in a confined space that it would be harder for somebody to commit a crime," says Nelson, "but in an assault like this, oftentimes it's easier, because it's harder for people to see, the close space and the seats pressed together make it hard for viewing, and the victims of this sometimes will not realize what's happening until it gets to a point of obviously unacceptable. There can be an 'oops factor' —[a person committing an assault will tell the victim] 'I accidentally touched your leg.' That's problematic."

The staff-to-customer ratio in plane cabins can also make it more difficult for flight attendants to monitor. "[The number of people in close spaces on planes is] also problematic," Nelson notes, "because flight attendants' ability to view it is diminished, and there are fewer flight attendants than ever, both in airlines in the US and in European carriers. Most are staffing at minimums, so we don't have as many eyes in the cabin to look for these issues as we could." (Delta, United Airlines, and Alaskan Airlines did not respond to requests for comment about their own protocols.)

The particular environment of planes can also make the experience of surviving sexual assault even more difficult. Mental health counselor Danielle Bostick tells Bustle that the cramped situation of planes in midair could exacerbate trauma. "Sexual assault is always a traumatic event," she says, "but when a victim is violated in a confined space, it can be even more distressing and exacerbate the feeling of helplessness, vulnerability, and powerlessness."

All these circumstances can make people who have experienced sexual assault on a plane reluctant to report it. “A lot of times these crimes go unreported because the victim feels ashamed, they feel intimidated by the person sitting next to them,” Robert Hughes, chief of the FBI’s section overseeing in-flight crime, told Quartz in 2015.

For many survivors of sexual assault on airplanes, the trouble does not end once they report the assault to staff. The New York Times reported in 2016 that flight attendants don't receive any kind of specialized training regarding sexual assault, and that "[u]nless police are called to meet the flight, it is up to the crew to decide whether to report disruptive behavior to the Federal Aviation Administration." Survivor reports often focus on the apparent lack of training by on-board staff for these types of events, despite the fact that incidents appear to have increased by up to 400 percent since 1995 and are on the upswing every year. Though many survivors report that crew members confronted their assailants and that the proper legal authorities were notified on the ground, this isn't always the case; a 2017 CNN Traveler piece, for example, quoted a survivor who reported her assault to crew members while onboard a long-haul flight, and was moved to a new seat by a flight attendant who told her that "Sometimes, you just have to let these things roll off your back;” she was told to sit next to her assailant again during landing, and after speaking with an airline representative once her plane landed, she was left with the impression that the airline expected her to contact local police to report the crime herself.

The lack of specific training regarding sexual assault means that plane crews may not understand why it needs to be handled differently than other on-board problems — a 2016 investigation by the Huffington Post found that sexual assault on major carriers is often treated the same as any other assault: separate the two people, re-seat them, keep everybody calm, avoid escalating the situation, and then use their discretion about whether or not to report to the authorities — a strategy that doesn't recognize how sexual assault is different from other kinds of physical attacks.

Experts agree that this is deeply problematic, and prevents survivors from being properly aided. "In my opinion," sexual assault educator Elizabeth Peace tells Bustle, "the victim's needs must be addressed immediately, removing the suspect from the victim right away while maintaining calm on the plane. I would not want to bring attention to the victim, who likely wouldn't welcome that at all and deserves privacy in such a horrific moment." Bostick agrees, saying "Proper training of flight attendants is critical because if a victim seeks help and is ignored — it is common for perpetrators to frame their violence as a misunderstanding — that can cause even greater distress for the victim, especially if he or she is not provided another seating option and is trapped next to the perpetrator for the duration of the flight."

"Flight attendants do need training on how to identify this," Nelson explains, "because this is a crime that is not obvious. There has to be some training provided to recognize the signs of this particular assault. It's not the same as when somebody is hit in the face. Training also has to include how to report and how to support the victim. Those are training components, but also I think it's really important that we recognize that conditions on the plane make this more likely and also make this more difficult for flight attendants to recognize."

American Airlines spokesman Ross Feinstein told the New York Times, "We’re reporting misconduct that occurred on the aircraft. It’s up to law enforcement to determine if any criminal misconduct occurred.” However, if airlines fail to notify appropriate law enforcement while the plane is in the air, survivors have few options. Once an alleged assailant and potential witnesses have left the plane, there is little that local law enforcement can do to advance an investigation, and survivors who sue airlines for damages often don't succeed in their lawsuits, due to the intricacies of air travel law.

So what can be done? Moves to legislate the issue haven't worked out so far; a 2014 attempt by by Rep. Eleanor Holmes Norton to pass the "Protecting Airline Passengers From Sexual Assaults Act,” which would have required the FAA to collect and publish information specifically about sexual assault cases on airplanes, failed.

But some airlines have taken it on themselves to experiment with new ways to deter assault. Air India announced in January 2017 that it would be marking out female-only sections on domestic flights after a spate of assaults on flights (it's worth noting that the airline's other major achievement this year was a flight on which all staff, from captains to ground crew, was female.)

Alcohol is often also a factor in these attacks — for example, a woman who admitted to "drinking heavily" pleaded guilty this March to sexually assaulting another woman on a flight — leading some to believe that tightening restrictions regarding on-board alcohol service would be helpful. Nelson agrees, but within limits. "Alcohol is absolutely a contributor to this crime, and to other crimes on the plane," she said, but believes that passenger education on how pressurized cabins affect your alcohol tolerance and on-the-ground training for airport staff about inebriation are a better idea than a ban. And even a total ban would do nothing to deter many assailants, or ensure that crew members know how to specifically handle sexual assaults.

The greatest hope, Nelson says, is consistent training across the airline industry itself. "Airlines can take it upon themselves to take on this issue as well, working with experts on training programs, working on their own internal reporting process," she tells Bustle, "and some airlines do a better job of this than others." This is, Nelson points out, a fraught endeavor at times, since airlines "may be concerned that if they're taking [on the issue of sexual assault], they are highlighting the issue and the name of the airline then gets associated with that particular crime. That's a real concern, and that gets in the way of airlines voluntarily being willing to take these issues on."

But committing to training staff, and to reporting assaults, is likely the only true way forward. And, Nelson observes, some companies have taken the lead here — "Some airlines have taken it upon themselves to identify sexual assault as a different type of assault in their training manual for flight attendants, and given some instruction about what to do." Though these types of staff training programs aren't standard yet, they're our best hope in making our skies truly safer.