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Flickr User Tony Webster // CC BY 2.0
Flickr User Tony Webster // CC BY 2.0

How Do Power Outlets On An Airplane Stay Grounded?

Flickr User Tony Webster // CC BY 2.0
Flickr User Tony Webster // CC BY 2.0

Airlines know we can’t go a few hours without our precious electronic devices, which is why many airplanes feature power outlets to help people stay plugged-in. Being able to charge your laptop like you would at home is a perk, but how is the electrical socket grounded when you’re 35,000 feet above the Earth?

A plug's grounding pin and the corresponding hole you see on an outlet you have at home is there for safety. In case of a lightning strike or power surge, that prong is connected to the Earth, which gives the excess electrical current somewhere to go besides an appliance (or through you while you are holding said appliance). Wiring airplane power outlets to the Earth below is obviously out of the question, so something else has to take the ground's place as a conductor to dissipate electric current. Luckily, an aircraft’s metal frame is perfectly suited for the job.

“If the third pin (‘ground’) on the receptacle were connected at all, it would be to the metallic structure of the airplane,” electrical engineer Roger L. Boyell tells mental_floss over email.

Grounding, after all, is just a term. As long as it can complete its circuit, electricity couldn’t care less about where the Earth is.

“Grounding on the airframe is analogous to grounding to the Earth,” turbomachinery expert Steven B. Kushnick tells mental_floss, also over email. To electricity, the airplane’s metal frame is a much more desirable conductor than a person, and any time there is stray or excess current, it will always take the easiest path.

Kushnick explains it thusly:

If you had one hand on the stainless steel sink in the lavatory (ground); and one hand on, perhaps, an electric razor that is plugged in and properly wired with a ground-prong, then stray electric currents would have no ‘desire’ to enter your razor-holding hand to get to your sink-touching hand (and shock you in the process) because the stray currents have a shorter circuit to travel: through the ground-prong to ground (airframe).

This remains true even in the event of lightning strikes. “Modern airplanes are frequently hit by lightning,” Boyell says. “Their skin is made electrically conductive to pass the current, much like through a wire, with no effect.” At most, this could “leak through to induce an electromagnetic field inside the airplane,” Boyell says, adding that it “could momentarily disrupt electronic instruments.” Even still, “an electrical device will be unaffected by whether it is plugged into a power outlet on the airplane or not.”

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Animals
Meet Piper: The Border Collie Making a Michigan Airport Safer for Travelers
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Birds may look harmless on solid ground, but in the sky they pose a big threat to any aircraft crossing their path. The Cherry Capital Airport in Traverse City, Michigan, uses a low-tech approach to the problem: a border collie named Piper.

Great Big Story profiled Piper and his handler, airport operations supervisor Brian Edwards, in a recent video. Piper’s job as the airport’s wildlife control canine is chasing away large birds that could strike incoming and outgoing planes, potentially causing anything from dents to engine failure. In Michigan, this usually means large waterfowl like ducks and geese, but it can also include crows, gulls, and snowy owls.

After he’s deployed from a moving car, Piper heads for the birds, scattering them away from the tarmac and teaching them to associate the area with predators. Piper is just doing what most border collies would do in the presence of a flock of birds, only in this case he gets to wear stylish protective goggles while following his instincts.

You can watch the full story below.

[h/t Great Big Story]

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travel
How to Win a Year of Free Flights From JetBlue
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JetBlue has an enticing offer for anyone resolving to travel more in 2018: Customers who book a non-refundable flight before December 15 will be automatically entered to win the airline's All You Can Jet Pass, Thrillist reports. That means a full year of free unlimited flights to 100 destinations in the U.S. and beyond.

If you already have, or are planning to, purchase a flight in the first half of December, no further steps are required: You're automatically in the running to receive one of the three available passes. And if you have no upcoming flights to book but a bad case of wanderlust, you’re also invited to enter. To do so, just mail a letter with your full printed name, address, phone numbers, and email address to: All You Can Jet Sweepstakes, Centra 360, 1400 Old Country Road, Suite 417, Westbury, NY 11590.

The randomly selected winner can start flying for free as soon as February 1, 2018.

All You Can Jet Pass flyers won’t be able to book multiple flights departing from the same city on the same day, and change and cancellation fees will still apply. Other than that, they can travel without limitations. Travelers get a complimentary plus-one for each flight they book, and they’re free to change their travel companion from trip to trip. There are zero blackout dates, so even on the busiest travel days of the year, winners can fly without paying a cent.

The free year of travel ends January 31, 2019. If they’re smart with their time, it’s possible for winners to visit every one of JetBlue's 100 destinations, including Jamaica, Los Angeles, and the Dominican Republic, by the time their pass expires. The only thing they'll need to worry about is finding the energy for all that travel.

[h/t Thrillist]

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