“Airplane mode” for a phone or a computer (or similar electronic device) suspends radio-frequency signal transmission by the device, and was originally intended for safe air travel. “Airplane mode” does not turn a phone into an airplane, but there are jokes.
 
“I just switched my phone to airplane mode and a small child appeared and started kicking me in the back” was posted on Twitter by RollmanInOz on December 10, 2015.
   
Other “airplane mode” jokes include “I dropped my phone from the fourth floor, but it was on airplane mode so it landed safely” and “I put my phone on airplane mode. Now it won’t stop calling me Shirley.”
     
 
Wikipedia: Airplane mode
Airplane mode, aeroplane mode, flight mode, offline mode, or standalone mode is a setting available on many smartphones, portable computers, and other electronic devices that, when activated, suspends radio-frequency signal transmission by the device, thereby disabling Bluetooth, telephony, and Wi-Fi. GPS may or may not be disabled, because it does not involve transmitting radio waves.
 
The name comes from the prohibition by most of the airlines of using equipment transmitting radio-frequency signal while in flight; using airplane mode prevents devices from transmitting.
 
When the “aeroplane mode” is activated, it disables all voice, text, telephone, and other signal-transmitting technologies such as Wi-Fi and Bluetooth. Wi-Fi and Bluetooth can be enabled separately even while the device is in airplane mode; this is acceptable on some aircraft. Receiving radio-frequency signals, as by radio receivers and satellite navigation services, is not inhibited. However, even receiving telephone calls and messages without responding would require the phone to transmit; a smartphone in airplane mode is effectively a PDA.
 
Twitter
RollmanInOz
@Rollmaninoz
I just switched my phone to airplane mode and a small child appeared and started kicking me in the back.
5:57 PM - 10 Dec 2015
     
Twitter
MeannMike™
@MeannMike
I just switched my phone to airplane mode and a small child appeared and started kicking me in the back.
6:11 AM - 13 Dec 2015
   
Twitter
Steve Rowe
@Shikonboss
I just switched my phone to airplane mode and a small child appeared and started kicking me in the back.
4:40 AM - 15 Feb 2016 from Rochester, South East
             
Twitter
The Art of Charm
@TheArtOfCharm
Just switched my phone into airplane mode and a small child appeared behind me and started kicking me in the back.
3:51 PM - 4 Apr 2016
 
Funny or Die
27 Goodest Tweets We Scrolled Past This Week #54
By Jason Flowers and Funny Or Die Sep 30, 2016
(...)
RollmanInOz
@Rollmaninoz
I just switched my phone to airplane mode and a small child appeared and started kicking me in the back.
5:57 PM - Dec 10, 2015
 
Twitter
Paul Stevenson
@hauntedmagazine
I just switched my phone to airplane mode and a small child appeared and started kicking me in the back….
12:19 PM - 17 Mar 2018
 
Twitter
🤣 The Dad Joke Man 😉
@DadJokeMan
I just switched my phone to airplane mode and a small child appeared and started kicking me in the back…
10:33 AM - 6 Mar 2019