Despite many security checks and lengthy processes carried out by the airport authorities, there are still some unexpected passengers who make their ways directly on board without any boarding pass.
And they are the ones who are born during a flight in mid-air. There have been many instances when the mother had to deliver her baby when she was flying at a height of thousands of feet above the ground increasing the plane's crowd.
Here we have a few fascinating ones.
The flight SV21 was on its way to New York from Jeddah in Saudi Arabia on June 15th, 2016 when the woman went into labor. Subsequently, the pilots were instructed to dump fuel and return to London.
But she gave birth on board and as soon as the plane landed in London, the mother and the baby were taken to the hospital.
Saw Ler Htu was flying to Myanmar from Singapore on April 22nd, 2016 when she went into labour. Luckily, she was accompanied by three doctors as passengers who helped her to deliver a baby boy along with the crew.
To pay tribute and gratitude towards the airlines, the mother named her baby after the airlines -- Saw Jet Star.
A Taiwanese woman was flying to The US on Oct 7, 2015, when she went into labour and delivered a baby aboard.
The lady whose surname was Jian supposedly lied to the ground staff of China Airlines about her pregnancy condition.
Therefore, the baby girl was granted American citizenship but her mother was refused from entering the United States. She was reportedly ordered to go back.
Irina Vasylkova was traveling to from Zyryanka to Yakutsk on May 9, 2014, when she went into labor midway.
She was then moved to a seat having more leg room to make her comfortable in a hope that she would give birth on the ground. But the twins did not wait.
Fortunately, there was an obstetrician on board who helped with the delivery.
The Polar Airlines decided to provide the trio with free flights for life.
The woman was 28 weeks into her pregnancy when she started having labour pains during the flight from Guinea to Burkina Faso in April 2017. (The dates of the flight have not been confirmed.)
The crew helped deliver a baby girl aboard.
It is yet not clear whether there was a doctor on board or not to assist with the delivery or whether the plane crew was trained for such events but both of them are doing fine.