Hello dear collegues!
How many times have you started to plan a flight, inspired by realism and then hit wall?
I'm talking about finding two destinations which in your mind find a realistic resonance and then, you get stuck on something weird and it kinda kills the mood?
Using my experience with RL aircraft handling as turn-around coordinator, I'll bring my two cents to, break or at least lower the obstacle "Aircraft loading" can become. By loading I mean, determining realistic loads depending on passenger figures, how to load and load limitations.
1/Basic Aircraft loading, bullet points:
-Aircraft are loaded from FRONT to REAR
-The First item IN (loaded) is the LAST item OUT (what is sometimes abbreaviated as "FILO")
-Airlines issue a priority of commodities, meaning for XYZ Airways (passenger) the most important item are the First class bags, then Transit bags, then "Local Bags" [...] Cargo.
-Some dangerous goods (cargo) cannot be loaded one next to another and need to be separated. This is also a very important part when it comes to positionning loads in an aircraft.
Below is an example of a priority list:
1/First class Bags 2/Transit Bags 3/Local Bags 4/Crew bags (noted D as "Duty") 5/Rush bags 6/Non-revenue staff bags (if isolated) 7/Cargo 8/Mail 9/EIC
2/Aircraft Holds/Compartements:
The standards are the following:
Zone 0 for the cabine (hence when the cabin areas are divided we have 0A/0B/0C (and NOT OA (OSCAR A))
Compartment 1 for front part of forward Hold (On ATR you have 1Left and 1Right)
Compartment 2 for Aft part of forward Hold
Compartment 3 for front part of aft Hold
Compartment 4 for Aft part of Aft Hold
Compartment 5 for Bulk hold
Compartment 6 (used in ATRs/Dash8) Bulk
FYI: There are cases when the operator will load cargo in the cabin (called "SOC") using a specially desinged "cloth container" embrasing the contours of the seats. Quit funny that stuff (at least for the rampies)
3/Weights and load dispatch:
Passengers! for aircraft with more than 30 seats (godda check that) the operator has to take the standard weights as opposed to weighing each and every passenger. These std weights account for passenger & their hand luggage.
Scheduled flight :
Adult : 84K
Male : 88K
Female : 70K
Child : 35K (from 2 to 18 Yrs old)
Inft : 10K (this can vary from airline to airline)
Charter flights have a lower weight: 79K for adults.
Back in class we used to do pax weight times 0.79 (i think) on the manual load & trim sheets which were based on 84K.
4/Bags, ULD, fun in an aluminium box!
Now we need to split all the commercial aircraft you know into two categories.
Mecanised Hold / Bulk Hold.
Think ATR, bags are loaded directly into the hold, vs 777 which has two mecanized holds and one (Big) bulk load.
The Airbus A32X familty can acctually be both, with one Hold mecanized and the rest all bulk. An airline can also put a pallet secured on the floor and load bags above it...
The big advantage of mecanized holds is that your are MUCH faster at loading the aircraft. The loads are secured using LOCKS and depending of the position and type the these locks a certain type of ULD can or cannot be loaded.
Ex: one AKH type container (Airbus A32X) can hold up to 35 bags (3,5m3). The A320 can hold up to 7 AKH. In a big hub, the inbound aircraft can have a dedicated container with all bags heading to the same next destination. The AKH will be offloaded on arrival from plane A and be directly delivered at plane B for the next destination without even having to handle the 35bags. Nice ha?
Before we get into details, lets see what ULD stands for!
ULD = Unit Load device
It can be a container (LD1, LD2, LD3 ...) or a pallet (P1P,P6P,AMP...)
Most of you have seen them beaten aluminum "cans" with weird markings and airline logos at the airport.
Croatia Airlines used to have AKH, the markings were AKH0354OU.
Your all smart folks, so your reading this gibberish and seeing two things : AKH (which i've mentioned before) and serves to identify the type. OU and the end which is the IATA designator for Croatia Airlines, so the last two letters identify the owner of the ULD. Lastly the numbers, here is our random variant, totally up to airline's own rules. You just can't have two baring the same number.
Quizz question: how much does ONE AKE cost?
Vocabulary 101: here is the root of "how things are called" when it comes to cargo loading space.
Its a Hold (Forward/Aft), with compartements (1/2/3.../5), where if mecanised hold there are Positions (43R) to put ULDs.
So theses ULD are loaded into positions. These positions are coded using the compartiment for the first digit and position in line, 1 being the most forward. Additionnally pallet positions are identified with the suffix "P"
So postion "11P" is the first Palet position in compartement 1 (meaning forward part of forward hold).
On A320 the AKH containers are loaded one behind the other, so the positions would be:
CPT : 1-------------/3--------/4-------/5
HLD: ------------------------------------/5
POS :-11, -12, -13, -31, -32,-41,-42
Aha no compartement 2? Well no, its up to the airline to decided what to name it. Their choice is also based on weight and balance stuff which I'll cover later.
Next example B763, which can load a varaity of ULDs. In this example its a B763 with a wide cargo door in the front and a narrow one in the back:
POS LD2 R: 11R, 12R, 13R, 14R, 21R, 22R, 23R, 24R, 31R, 32R, 33R, 34R, 41R, 42R, 43R
POS LD2 L: 11L, 12L, 13L, 14L, 21L, 22L, 23L, 24L... 31L, 32L, 33L, 34L, 41L, 42L, 43L
POS LD7 : 11P..........12P.......21P........22P...........//NO palets here as they would not fit through the door
POS LD8/11 : 11, 12, 13, 14, 21, 22, 23, 24, 31, 32, 33, 34, 41, 42, 43
5/ULDs:
Here is a brief table of most common bagage used ULDs
ACFT (designed for) // ACFT can be loaded in-------/ Name /ULD / Empty weight / MAX bags
A320 ..................//A33x*/A34x* ................../ LD3-45 /AKH / 90KGS / 35 BAGS
B77x/A33x/A343....// B76x* ........................../ LD3 / AKE / 83KGS / 43 BAGS
B76x..................//B77x* .........................../ LD2 / DPE / 65KGS / 35 BAGS
B763..................//B77x/A33x*/A34x* ............/ LD8 / DQF / 120KGS / 70 BAGS
B74x..................//B77x/A33x*/A34x* ............/ LD1 / AKC / 90KGS / 47 BGS
*= Depending on locks, limited number of positions certified.
More info :