Bombardier Challenger 604 dual engine failure

The NTSB will be looking at all factors to establish the failure chain.

Given dual engine flameout indicates a common cause, evidence to rule in or out fuel system starvation and icing will include:

- Flight data recorder fuel tank quantities, fuel temperatures, and cutoff valve positions

- KOSU's samples of jet A, FSII ("Prist" DEGMME) for water content, and vendor and customer purchase records. The aircraft's operator should've purchased A+FSII and it should've contained DEGMME ~0.125% by volume when fueled. Prist is mixed in during fueling but it has to be stored carefully because it's hygroscopic. KOSU's fuel equipment, supply chain, and practices should all be reviewed.

- Records of draining water from fuel tank bleed valves

CL 604 limitations document from Canadair[0]

0. (PDF) https://www.smartcockpit.com/docs/CL_604-LIMITATIONS.pdf