01/09/2013 09:43 EST | Updated 03/11/2013 05:12 EDT

Pilot error, bad weather caused fatal Yellowknife plane crash: safety board

YELLOWKNIFE - A Transportation Safety Board investigation has concluded that the fatal crash of a plane on a Yellowknife street was caused by pilot error and bad weather.

The pilot and co-pilot were killed and seven passengers injured on Sept. 22, 2011, when a Twin Otter float plane tried to land on Great Slave Lake near the northern capital's Old Town.

Bystanders tried desperately to save the lives of the two pilots by administering CPR as people rushed from a nearby restaurant with blankets and towels. But Nicole Stacey, 26, and her fellow pilot Trevor Jonasson, 36, died in the crash near the float-plane docks, not far from the Bush Pilot's Monument.

Witnesses described the impact as "a huge crash, kind of like thunder."

In a report from Gatineau, Que., the safety board concluded the crash occurred when the crew attempted a landing in "gusty and variable" winds.

"The aircraft bounced, then porpoised and landed hard on the right float," the report says.

It says the pilots tried to recover by simultaneously climbing and circling around to the right, towards the shore — a manoeuvre beyond the aircraft's capabilities.

"The aircraft lifted off the water with its nose very high and the right wing low. In this configuration, the aircraft could not accelerate or climb."

The Twin Otter then hit power lines and the side of a building before coming to rest in a parking lot.

The plane was returning to Yellowknife from a remote mining exploration camp about 100 kilometres east of the city. Four of the passengers were seriously hurt and three had minor injuries.

No one on the ground was hurt.

Stacey was a military reservist and a third-generation aviator. Jonasson was married with no children.