The NBC10 Investigators have been digging into the pilots' background and the requirements to fly the type of aircraft that crashed on Friday, Jan. 31 in Northeast Philadelphia.
The pilots flying the Learjet55 were Mexican so when our team looked up their credentials with the FAA, it was either non-existent or didn't add up to the work they were doing on Friday.
It turns out that international-based pilots do not have to register with the FAA. There is an international organization that sets the standard for pilots all around the world.
As the NTSB looks at the evidence, other investigators have also been digging into records elsewhere.
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The NBC10 Investigators recently caught up with recently retired director of the FAA's Aviation Accident Investigation team, Patrick Hempen.
"They're looking at the pilot records, they're looking at the training records of the crew. They're probably going to go with the last flight simulator," Hampen explained.
Hampen also explained that the investigation into the cause of the Learjet55's quick nose dive into the ground is an all-hands-on-deck situation.
"The NTSB and the FAA do parallel investigations simultaneously together. And the NTSB has lead," Hampen said.
He said that the NTSB is looking at probable cause and the FAA is in the background looking at how they can improve operational safety by what happened with this accident.
The NTSB shared with our investigators that the company that owned the airplane, Jet Rescue, was authorized to operate in the United States airspace.
The agency also said that the Mexican pilots, Captain Alan Alejandro Montoya Perales and co-pilot Josue de Jesus Juarez Juarez, had the proper licensing required to fly a Learjet55 and they were certified to fly in inclement weather.
"I saw no red flags. I looked at it and I said, 'if I was ramp checking that aircraft, that's exactly what I want to see,'" Hampen said.
Jet Rescue, the company that owned and operated the plane that crashed told NBC10 that the pilots had years of experience flying in the U.S. and internationally.
The pilot had 8,700 hours and the co-pilot had 2,600 hours of flight time.
Hampen said that international pilots fly in U.S. airspace all the time and vice-versa.
The International Civil Aviation Organization is what sets the global standard to aviation.
"We rely on each government and they rely on us to do the correct licensing and to have the correct training and certification," Hampen explained.
The FAA does spot-checking at airports to ensure pilots do have proper certificates.
"They will walk over to the aircraft for us to see the pilot's license, medical and aircraft registration, airworthiness certificates, look at the load manifest, those kinds of things," according to Hampen.
Hampen said that when flying a Leerjet, there is a quick checklist of things that have to happen right after take off.