Pope Francis left New York City to head to Philadelphia Saturday morning (afternoon in Europe) as several hundred people waved him goodbye at John F. Kennedy Airport.

The pontiff, who suffers from sciatica and a bad knee, stumbled slightly as he walked up the stairs into the waiting American Airlines jet around 9am. He recovered quickly and waved to the crowd after he was seen limping as he headed towards the plane.

Before he departed, Francis met with nuns and Catholic leaders on the tarmac.