Load and Trim Sheet: Legal Mass-Balance Record and Take-off Trim
Purpose
The Load and Trim Sheet is the legal record of the aircraft's mass and balance calculation for a specific flight. It serves two main purposes:
- Mass Check: Ensures MTOM, MLM, and MZFM limits are respected.
- Balance Check: Ensures the CG is within limits and determines the take-off trim setting.
Sections of the Sheet
1. Header
Flight number, date, registration, crew configuration (e.g., 2/4), and airport codes.
2. Loading Distribution
Breakdown of passengers and cargo in each zone/hold.
- Traffic Load: Sum of all passengers, bags, and cargo.
3. Mass Build-up
- Dry Operating Mass (DOM)
- + Traffic Load
- = Zero Fuel Mass (ZFM) (Check against MZFM limit)
- + Take-off Fuel
- = Take-Off Mass (TOM) (Check against MTOM and Performance/Runway limits)
- - Trip Fuel
- = Estimated Landing Mass (ELM) (Check against MLM)
4. Trim Calculation (Balance)
Uses an index system (graphical "drop line" or numerical table) to calculate the final Index or %MAC.
- Result: The Take-off CG position (usually in %MAC).
- Action: Determines the THS (Trimmable Horizontal Stabilizer) or Trim Wheel setting required for take-off (e.g., "4.5 Units UP" or "28%").
Commander's Signature
The commander (captain) must sign the load sheet, accepting responsibility that the loading is within limits.