With how much weight a plane can take off and land is decided upon even when the plane is a conceptual design (idea). In order to fly safely, the plane is designed in a way that these weights are taken into consideration and all indispensable parts and hardware are the lightest. So, in the end, there is a weight value the plane will have without the fuel it will take. The airlines are finding out their gross weight they can carry (they can sell) after adding fuel weight to the weight mentioned above. This is called payload in aviation.
For instance, if 20 tons of fuel is required for a plane weighing 35 tons with a total 75 tons of take-off weight, there are 20 tons left for the passengers, luggage and the offerings. That means each passenger has 100 kg on average in a 200-person plane.
Each and every weight added without paying the regarding flight is a cost item out of countenance of the airway because of the consumed fuel amount. While that item is accepted as a natural part of the operation for some companies and reflected on the ticket prices, it turns into an important criterion defining the competition for low cost airways that are getting share from the market with price advantage they offer.
If the passenger’s weight is 80 kg and he/she carries a luggage heavier than 20 kg, it means a potential problem for the airway. As that another passenger’s luggage should be lighter or the passenger has to finance the additional load, luggage limitation is subjected to strict rules. It still is not enough for the passenger to say “I can’t leave anything in my luggage, I comply with the penalty, I can pay whatever the price is” because if that happens, then additional obligations such as weighing scale for the luggage, luggage report and making collections are involved and the burden of the airway grow apace. This is the reason that demanding huge amounts even for 1 kg of additional weight is inevitable, thus the price advantage is lost for the passengers. Especially in Europe, some airways are determining astrological prices to deter passengers from taking additional luggage.
In a plane where the question “Can’t they make these pitches 2 cm more?” is asked, assuming that there are roughly 35 rows of seats, it means that (2 cm x 35 seats) an extra space of 70 cm is demanded. That means that a row will be taken out of the plane. A row of seats is equal to 6 passengers, 3 on the left and 3 on the right wing, and it makes 18 passengers for a plane plying 3 times a day; it makes 450 passengers monthly and more or less 5000 passengers in a year; and all this calculations are just for one plane. Annual value is 100 thousands passengers for an airway with a 20-plane squadron. We are talking about a passenger size that a 200-person plane can carry in 500 times. That means an airway has to abandon 100 thousands passengers just to relax passengers with 2 cm. As the expenses will change simultaneously in the same direction and the airway will have to reflect these losses to the tickets of the remaining passengers, 2 cm becomes an important value for the airway to offer affordable prices.
And a passenger complaining that “There is no magazine even to read, I’m bored!” is showing his desire to exceed the 100 kg limit allocated to him/her. Average weight of the free magazines placed at the back of the seats for the passengers to read are assumed as 250 gr and in a 200-person plane, it makes up 50 kg additional load. In a plane flying 4 hours approximately, 10 litres of additional fuel is required to carry 50 kg additional load. And for a plane flying 3 times a day, it makes 75 flight monthly and 825 flights annually and that is equal to 8250 litres additional fuel. It makes 165 thousands litres additional fuel for a 20-plane squadron. Knowing that the total fuel capacity of the mentioned plane is 30 thousands litres, it will ferry more than 5 times annually just due to the magazines.
All these costs are the same for offering a glass of water. Thus, an airway wanting to offer a glass of water to its passengers will have to pay for a cost of fuel almost equal to the cost of 250 gr free water including the weight of the glass well.
To sum up, a gap of 2 cm, a magazine of 250 gr and offering a glass of water that an airway with a squadron of 20 200-person planes and plying 825 times a year; will mean losing 100 thousands passengers and 330 thousands litres additional fuel consumption.
These examples are of course are far from being decisive when compared to the indorsement of an airway; however, they are highly appropriate examples to show that even the details that seems to be the most simple how can affect the budget of an airway. The engineering groups also will have to make decisions in the manufacturing stages regarding the same delicate balances before the operator airway of the plane. Similar decisions are to be taken in almost all industry branches but in aviation industry, they are more apparent and that makes them tend to be more critical.
Payload is a value of great importance for the airliners. Especially for the airlines such as Ryan Air, Easy Jet that are trying to survive with the cheapness of the tickets they sell and providing subgrade service, these items at their own disposal are eliminated from the very beginning. Also this is the reason for the seats to get thinner and lighter continuously in the planes making these kind of works. Even the idea to take out the toilets for the short flight are beginning to be taken into consideration seriously. And sacrificing offerings for the sake of competition also becomes inevitable.
* Average/approximate value as it depends on the plane model and the region it flies