grumbles69
Current Weight & Balance based on Free-seating relies on an even spread of passengers throughout the cabin. The cabin crew may well move passengers to achieve this. This is fine on on full-ish or full flights etc. If the flight has a low load however, the cabin crew will count the exact number of passengers seated in certain cabin rows. The cabin is split into 3 bays A/B/C.
This seating distribution is then fed into the weight & balance notebook computer on the flight deck along with the number of Males/Females/Children/Infants and with details on hold baggage weights loaded into set holds of the aircraft.
The trim settings and Take-Off V speeds obtained are then entered into the aircrafts flight management computer.
If Allocated seating systems do not manage the aircraft passenger distribution in a sensible and balanced way; then the aircraft may be in a state in which it would be outside of the prescribed flight envelope on take-off!
ie. like my name, it would be considered Out of Trim! To get the aircraft back in trim, either passengers or baggage or indeed both may have to be moved with the inevitable delays this would cause!
Re DPNA is an IATA code.
SPECIAL SERVICE REQUEST (SSR) CODES
The following are the IATA codes applying to disabled persons and persons with reduced mobility requiring assistance:
MEDA Passenger whose mobility is impaired due to clinical cases with medical pathology in progress, being authorised to travel by medical authorities. Such passenger usually has social coverage in relation to the illness or accident.
STCR Passenger who can only be transported on a stretcher. Such passenger may or may not have social protection or specific insurance.
WCHR Passenger who can walk up and down stairs and move about in an aircraft cabin, who requires a wheelchair or other means for movements between the aircraft and the terminal, in the terminal and between arrival and departure points on the city side of the terminal.
WCHS Passenger who cannot walk up or down stairs, but who can move about in an aircraft cabin and requires a wheelchair to move between the aircraft and the terminal, in the terminal and between arrival and departure points on the city side of the terminal.
WCHC Passenger who is completely immobile who can move about only with the help of a wheelchair or any other means and who requires assistance at all times from arrival at the airport to seating in the aircraft or, if necessary, in a special seat fitted to his/her specific needs, the process being inverted at arrival.
BLND Blind.
DEAF Passenger who is deaf or a passenger who is deaf without speech.
DEAF/BLND Passenger who is both deaf and blind, who can only move around with the help of an accompanying
person.
DPNA Disabled passenger with intellectual or developmental disability needing assistance.
