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Commercial Airplane Op
QUESTION: Dear Ned

1. Is the Cargo carrying capacity (Load, Weight) fixed or standard in all Commercial Airplane Carriers ?. Is this done for Security measure for not exceeding the total weight, load of the airplane i.e passengers, cargo, fuels, airplane etc ?

2. Is there a certain Total Load or Weight of the Airplane which cannot be exceeded ?. Is this identified by Electronic Instruments panel, Alarms etc indicating the Total Weight, Load of the Airplane to the pilot before flight takes off ?.

3. In case if the Total Load or Weight of a Airplane is exceeded
and still the Pilot tries a take off, can it lead to plane crash ?

Thanks & Regards,
Prashant S Akerkar

ANSWER: Hi Prashant, during the initial certification of an airplane the maximum takeoff weight is determined. This weight is based on sea level altitude, standard temperature, and no wind conditions using the maximum power on the engines.

This weight includes sthe weight of the aircraft, the fuel and the payload.

During normal operating conditions this maximum weight is adjusted to account for the actual temperature, altitude and wind conditions.

Some airplanes have an electronic readout of the actual weight of the airplane, but this is not in widespread use.

Normally the pilots input the data into a flight management computer on the airplane.

Exceeding the maximum weights could contribute to an accident.

Hope this helps.

Ned

---------- FOLLOW-UP ----------

QUESTION: Dear Ned

Thank you.

As you mention, during the initial certification of an airplane, the maximum takeoff weight is determined. Can this be considered as a part of Airplane Load / Stress Testing methods ?.

Can we derive some mathematical formula or equation to calculate / compute the Total Weight of the Machine (Airplane) before takeoff ?

Parameters : temperature, maximum power of the engines etc

1 Ton = 1000 kg

Example :

1. Aircraft Weight : x kg - Construction (Manufacturing)
2. Fuels Weight : y kg - Construction (Manufacturing)
3. Passengers Weight : z kg - Load - Includes Crew Cabin - Pilot, CoPilot, Captain etc - Load
4. Cargo Weight : - n kg - Load
5. Miscellaneous Weight - Furniture - Seats, Tables, Utensils - Dishes,Glasses etc) - m kg - Load

Total Weight of the Aircraft W in Tons = x + y + z + n + m.

Should we add safety factor value to this total weight ?

Do you feel electronic instrument panels calculating and showing the Total
Weight (Load) of the aircraft can be useful for Pilot before he takes a take off ?. Alarms will buzz to the Cabin Crew if Overload occurs within the aircraft before the Take Off.

Among different accidents, which are the most likely to occur because of Aircraft Overweight ?

1. During Takeoff.
2. During Landing.
3. During Aircraft flight (i.e. After Plane Takeoff and Before landing).

Thanks & Regards,
Prashant S Akerkar

After the aircrafts' designers have produced an aircraft they put it through an exhaustive series of tests to prove that their design will perform as they forecast. After the design criteria have been proven some percentage of the actual performance is reduced to provide a safety margin.

Of course the design process uses many formulas to calculate the expected performance.

Electronic readouts of aircraft weight would only be useful for comparing the actual weight of the aircraft with the maximum allowable on a standard day. The weight that would be allowable on a normal flight would be affected by temperature, wind, altitude, length of runway and a host of other variables.

I think the takeoff would be the most likely to be affected by overweight.

I sure hope I am not doing homework for you!!

Ned
Questioner's Rating
 Rating(1-10) Knowledgeability = 10 Clarity of Response = 10 Politeness = 10 Comment Dear Ned Thank you. Thanks & Regards, Prashant S Akerkar

Aviation/Flying

Volunteer

#### Ned Dolan

##### Expertise

38 years as a professional pilot. Worked as an instructor for a major airline, as a tow pilot towing gliders and flew international routes until 1998. Do not know much about the maintenance end of the business.

##### Experience

Teaching new Captains the skills and knowledge needed to occupy the position. Helping develop procedures for use in a new airplane type. (B757)