P&L W&B Flashcards
CG checks at TAXI and ZFW are required because as fuel is burnt in flight the CG
moves!
Advantages of using stabiliser trim are that
it reduces drag, preserves elevator travel and permits a smaller elevator
The MAC of a swept wing is defined being equivalent to the chord of an unswept rectangular wing of the same area, or the chord through
the centroid of the area.
The %of MAC is the distance from back along the chord from the
the leading edge
The representation of the aircraft CoG as a %of MAC permits comparison of the CG relative to the wing.. .. .
Centre of Pressure!
The distance between the CP and CoG determines the magnitude of the .. ..
pitching moments which must be balanced with pitch trim for take-off!
When loading a tricycle undercarriage aircraft, cargo should be first loaded into the front compartments and pax into
centre/front zones to prevent over balancing!
The nosed down pitching moment produced by a rear CG produces is weak and produces less ‘induced drag’ than a FWD CG.
FWD CG’s require larger stabaliser A….
stabaliser AOA’s for the same speed –> which produces more induced drag compared to a rear CG.
Less drag is produced for a given weight and speed with a …..
Rear CG position!
With a rear CG, the arm from CG to tail plane is short so the tailplane is
LESS effective, consequently in the cruise there will be reduced longitudnal stability and light elevator forces to effect pitch changes. .
When fuel is added as ballast
it is considered UNUSABLE and the BW needs to be increaseed by the weight of the ballast fuel!
THIS REDUCES PAYLOAD capacity!
Max PAX - 138
Plus 6 Cabin Crew
- 144 seats -
Empty weight includes equiptment whcih has a fixed location and is actually on the aircraft when it is weighed, inlcuding…..
ALL engine oil, hydraulic fluid & unusable fuel!
EW + Operational Items =
BEW
Operational Items include cockpit documentation, cabin equiptment as well as
crew and galley provision!
