The Coulson Aviation practice of recalculating the target retardant drop airspeed after a partial drop reduced the post-drop stall speed and energy‑height safety margins.
The amendment to the Coulson Aviation Flight Operations Manual to prohibit the recalculation (lowering) of drop speeds following a partial load drop should adequately address this safety issue.
Coulson Aviation published Fixed Wing Operations Bulletin 23-2 to prohibit the recalculation (lowering) of drop speeds following a partial load drop. This was incorporated into their fixed-wing Flight Operations Manual on 10 October 2023 with an amendment to include an Airtanker Procedures section with a subsection for Recalculation of Airspeed during Partial Load Drops.
