Per the FAA site, the Federal Aviation Administration has asked the public not to turn on or charge the Samsung Note 7 on board aircraft and not to stow them in any checked baggage.
If you haven’t heard, there has been a massive recall on Samsung Note 7s as they were exploding on the charger. The phone retails for near $1,000 USD and the recall/exchange program is pulling back 2.5 million of them.
The issue appears to be in the construction of the battery used inside the phablet. Any damage to the internal mechanics of the cell or imperfections in the electrolyte can raise the risk of a short-circuit.