iPhone Fire
The Apple iPhone 4 after its mid-flight combustion. The smartphone began to burn as the plane prepped for landing. Regional Express

The Apple iPhone 4, like the iPhone 4S, has been flying off the shelves for months, but this hot gadget still has some kinks to work out: while on a flight over Australia on Nov. 25, one user's iPhone became literally too hot to handle, glowing red and smoking before having a minor combustion.

The passenger, whose name has not been released, was taking Australian flight Regional Express ZL319 from Lismore to Sydney. During the landing, his iPhone 4 suddenly started emitting a significant amount of dense smoke, accompanied by a red glow, according to an official statement by Regional Express.

As black smoke filled the cabin, passengers on the airline discovered that the phone appeared to have combusted.

In accordance with company standard safety procedures, the statement continued, the flight attendant carried out recovery actions immediately, and the red glow was extinguished successfully.

After landing in Sydney, the phone was handed over to officials from the Australian Transport Safety Bureau (ATSB) as well as the Civil Aviation Safety Authority (CASA) for investigation. The back on the iPhone 4 had melted and been pushed outward by the heat. No passengers or crew members were harmed.

iPhone, iPod Touch Fires

Although no report has been released on what may have caused the iPhone 4 to combust, CASA has issued a warning advising against using electronic devices using lithium batteries while in flight.

The Australian safety authority recommends limiting lithium batteries to two per flight, and requires them to be placed in separate bags to prevent the battery from short circuiting.

Though the model has been reported as an iPhone 4, not the new iPhone 4S, this is not the first time an Apple smartphone has overheated and caught fire, even causing minor explosions.

In 2009, the European Union launched a far-reaching investigation into Apple products after multiples cases of iPhones and iPod Touches exploding or catching fire mid-flight were reported to authorities in Holland, France, Sweden and the UK.

Apple also recalled the first generation of iPod nanos sold between September 2005 and December 2006 because of the products' lithium ion batteries overheating. The company reported that the battery heat could pose a safety risk, but the second generation of nanos were confirmed safe to use on-flight.

Danger of Lithium Batteries

Nor is Apple the only company whose electronic devices have come under fire for dangerous battery overheating.

In December 2010, a man in north Texas reported that his Motorola Droid 2 smartphone exploded next to his ear when he was finishing a call.Aron Embry said he heard a loud pop from his phone, which was just two days old, before the glass covering on his Droid 2 shattered, bloodying his face and sending him to the hospital.

The incident resulted in a trip to the Emergency Room and a bloodied face, though no hearing loss was recorded. Remarkably, the phone itself was still working after the explosion.

Apple has not yet released a statement about the iPhone 4 fire. Luckily, the newer iPhone 4S model appears to be working fine, with only SIRI stalls and occasional, minor overheating reported.