A floatplane which crashed and burned earlier this month near Willow Lake, killing its pilot and leaving a mother and child severely injured, was carrying a variety of supplies including propane tanks when it went down according to federal investigators.

The National Transportation Safety Board’s preliminary report on the July 18 crash of a Regal Air flight which killed 24-year-old Colt Richter was released Tuesday. Witnesses to the crash have told KTVA that the de Havilland Beaver circled on the lake’s surface three times before taking off; the plane crashed soon afterward.

According to the NTSB, the woman and her 2-year-old son had been en route from the Willow Seaplane Base to a remote lake 61 miles northwest of Willow. The flight, which was chartered by the Alaska Medicaid Travel Office, was the return leg of a trip to the seaplane base.

Tracking data from the plane showed it taking off from Anchorage’s Lake Hood Seaplane Base just before 6 p.m. on the night of the crash, reaching the Willow Seaplane Base about 20 minutes later.

“Witnesses reported that after arriving at the Willow Seaplane Base, the pilot loaded the passenger's cargo, which according to a statement provided by the passenger, consisted of multiple bags of masonry mortar, three totes full of food and stores, two propane tanks, and miscellaneous baggage and supplies,” investigators wrote. “Just prior to departure, the passenger was seated in the second row with her son on her lap.”

Witnesses told the NTSB that the plane “appeared heavy” during two takeoff attempts, followed by a third one. Several people recorded video of the takeoff due to its unusual nature.

“Each witness stated that the airplane departed to the south and descended out of sight below the tree line,” investigators wrote. “Soon thereafter, a loud airplane impact was heard.”

A resident southeast of Willow Lake just after the 7 p.m. crash stepped outside to find “the passenger walking with her son in her arms, outside of the airplane which was engulfed in flames.”

Soon afterward, Richter was found dead by firefighters when they extinguished the aircraft. According to the NTSB, the fire “incinerated the fuselage, empennage, floats, and cargo.”

NTSB investigator Noreen Price, who is handling the incident, emphasized Tuesday that she couldn’t confirm that the plane was overloaded, in large part due to the fire after the plane’s crash. No communications from Richter were received prior to the crash.

“I honestly don’t have any evidence at this time to say whether the plane was or was not over weight limits,” Price said.

The propane tanks carried during the flight were filled, Price said. Although the Federal Aviation Administration bars passengers from bringing propane on board commercial airliners, smaller carriers like Regal can choose whether to accept or reject propane or other hazardous materials.

“It is a ‘will-carry’ company,” Price said. “They can fly it, provided that it is documented appropriately.”

The surviving woman’s account of the plane’s loading is the only one available of the cargo and its positioning, Price said.

“Because all the cargo was destroyed in the fire, part of the investigation will be rebuilding the cargo,” Price said. “We’re working with the passenger and the company she bought the cargo from so we can determine what the takeoff weights were.”

The NTSB will also be evaluating Regal Air’s procedures to ensure they were followed in the loading of the aircraft, Price said. Although carriers often have a general knowledge of cargoes for planning purposes, pilots are ultimately responsible for their planes’ weight and balance.

“It is the pilot in command’s responsibility to ensure that the plane is loaded and operated in accordance with its limitations,” Price said.

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