2. Safety hazard due to sudden and developing damage in transport systems

Despite many efforts in the processes of designing and implementation of new aircraft constructions, the occurrence of not signalled (sudden) damage, the effects of which are serious, took place. They may occur in the process of operation for many reasons, and mostly due to the lack of complete recognition of many processes that take place during the aviation equipment operation. So far, there has been also a lack of methodology for optimal shaping of construction elements based on destruction models, which would take into account all possible types of their loads and assessment of the environmental impact effects in the long-term operation.

where R(t)—probability of failure to the catastrophic damage occurrence.

E[K]min

Figure 1. Diagram for determination of the acceptable range of the risk of losses.

Obszar dopuszczalnego ryzyka

Area of the acceptable risk

E[K]—expected value of the total cost E[K] = E[O] + E[S].

3.1. Classification of construction systems and wear processes

result of the occurrence of catastrophic damage in the operation process.

able' risk policy based on the principle 'as low the risk, as it is reasonably achievable'.

3. Types of damage causing threats and models for assessing the

order to eliminate catastrophic damage).

during operation resulting in catastrophic damage.

probability of their occurrence

be presented.

Koszty

Costs

E[S]

E[K]

E[O]

E[O]—expected value of the cost of developing the construction and reliability test (in

Poziom bezpieczeństwa

Safety level

Probabilistic Methods for Damage Assessment in Aviation Technology

http://dx.doi.org/10.5772/intechopen.72317

39

Reliability

1,0 R(t)

E[S]—expected value of the risk resulting from the frequency of the failure and losses as a

Figure 1 shows the possibility of moving from the zero-risk policy of a threat to the 'accept-

The basis for estimating the risk of threat is a forecast of the occurrence of negative phenomena

In this chapter, the selected models, which can be used for estimating the reliability and risk of the occurrence of catastrophic damage in the accepted time period of the device operation, will

By assumption, the aviation technology has high reliability requirements, which, in practice, are implemented through special inspection procedures and appropriate design solutions involving the introduction of excesses of structure, strength, power, information, etc. The structural excess is characterised by elements or functional systems, basic and reserveprotective ones. After damage to the basic system, the protection systems start functioning. It ensures a high safety level of aircraft flights, which is one of the most important issues in the

For example, it is possible to distinguish some causes of sudden (catastrophic) damage. They are as follows [1]:


All the causes leading to catastrophic damage are the subject of numerous experimental and theoretical considerations.

The occurrence of catastrophic damage to the aircraft equipment usually results in serious failures or catastrophes and large losses. Therefore, it is necessary to estimate the risk of incurring these losses.

The term of risk is understood as the probability of the occurrence of critical damage or an adverse event in case of the occurrence of losses. In our case, a negative phenomenon will include the occurrence of catastrophic damage to aircraft. The level of the accepted risk of negative events is determined by the frequency of their occurrence and costs. In Figure 1, a method for determination of the accepted risk range is presented.

Figure 1. Diagram for determination of the acceptable range of the risk of losses.

The second way is to use an external central computerised system of monitoring and analysing the operation process of the entire set of objects, including a system of recording operational events and an information processing system. The system of recording information obtained during diagnostic checks and detected damage divided by types, symptoms, causes and effects is of particular importance. The recorded data are used for determination of the reliability and safety characteristics, and provide the opportunity to estimate a functioning resource.

2. Safety hazard due to sudden and developing damage in transport

loads and assessment of the environmental impact effects in the long-term operation.

fatigue crack, which exceeded the critical value.

foreign matters between the cooperating elements.

circumstances conductive to uncontrolled explosions.

method for determination of the accepted risk range is presented.

• The random shortcuts in the electronic circuits.

Despite many efforts in the processes of designing and implementation of new aircraft constructions, the occurrence of not signalled (sudden) damage, the effects of which are serious, took place. They may occur in the process of operation for many reasons, and mostly due to the lack of complete recognition of many processes that take place during the aviation equipment operation. So far, there has been also a lack of methodology for optimal shaping of construction elements based on destruction models, which would take into account all possible types of their

For example, it is possible to distinguish some causes of sudden (catastrophic) damage. They

• The loss of the volume strength of the element, which can be damaged as a result of the occurrence of excessive permanent deformations, the occurrence of an ad hoc crack, or a

• The loss in material properties in the construction elements as a result of functioning of

• The loss of the element's usability as a result of the surface wear or the inclusions of

• The random increase in the concentration of vapours of chemicals and the occurrence of

All the causes leading to catastrophic damage are the subject of numerous experimental and

The occurrence of catastrophic damage to the aircraft equipment usually results in serious failures or catastrophes and large losses. Therefore, it is necessary to estimate the risk of

The term of risk is understood as the probability of the occurrence of critical damage or an adverse event in case of the occurrence of losses. In our case, a negative phenomenon will include the occurrence of catastrophic damage to aircraft. The level of the accepted risk of negative events is determined by the frequency of their occurrence and costs. In Figure 1, a

systems

38 System of System Failures

are as follows [1]:

ageing processes.

theoretical considerations.

incurring these losses.

where R(t)—probability of failure to the catastrophic damage occurrence.

E[O]—expected value of the cost of developing the construction and reliability test (in order to eliminate catastrophic damage).

E[S]—expected value of the risk resulting from the frequency of the failure and losses as a result of the occurrence of catastrophic damage in the operation process.

E[K]—expected value of the total cost E[K] = E[O] + E[S].

Figure 1 shows the possibility of moving from the zero-risk policy of a threat to the 'acceptable' risk policy based on the principle 'as low the risk, as it is reasonably achievable'.

The basis for estimating the risk of threat is a forecast of the occurrence of negative phenomena during operation resulting in catastrophic damage.

In this chapter, the selected models, which can be used for estimating the reliability and risk of the occurrence of catastrophic damage in the accepted time period of the device operation, will be presented.
