031 Mass & Balance

EASA code: 031

Mass & Balance covers aircraft mass terminology, structural and performance limits, centre of gravity theory, loading calculations, and EASA standard masses.

Chapters

1. Mass definitions — BEM, DOM, ZFM, TOM, useful load
2. Mass limitations — structural vs regulated, MFZM, floor load
3. Centre of gravity — datum, moment, arm, indexes
4. MAC & envelope — LEMAC, %MAC, CG limits
5. CG & performance — forward/aft effects, Vs scaling
6. Loading calculations — load shift, transfer, load sheet
7. Weighing & standard masses — fleet masses, EASA pax masses
8. Key notes — quick revision

Exam focus

• Mass definitions (BEM, DOM, ZFM, OM, TOM, LM)
• Regulated TOM = lowest of MTOM, MZFM + TOF, MLM + trip fuel
• Moment = mass × arm; CG = total moment ÷ total mass
• %MAC and load shift formula d/D = m/M
• Vs scaling: Vs new = Vs old × √(new mass ÷ old mass)
• Forward vs aft CG effects on stability, range, stall speed
• Standard passenger/crew masses and fleet weighing intervals