Apa, 46, is one of the most respected climbers in the mountaineering community. His closest competitor -- fellow Sherpa guide Chewang Nima, 41 -- scaled the peak a 14th time last year.
Apa was leading a team calling themselves the "Super Sherpas Expedition" on a charity climb to raise education funds for children of the Nepalese mountain guides.
He and his teammates had set out to make a documentary about the climb and all money raised will go toward providing better education and health care for children in their community at the foothills of the mountain.
Like most Sherpas, Apa grew up in the foothills of Everest, and began carrying equipment and supplies for trekkers and mountaineers at an early age.
He made his first summit of Everest in 1989 and has been climbing almost every year since.
Sherpas were mostly yak herders and traders living in the Himalayas until Nepal opened its borders to tourism in 1950. Their stamina and knowledge of the mountains make them expert guides and porters for foreign mountaineers.