The theoretical subject "Operational procedures / behaviour in special cases" deals with the procedures that must be followed to ensure safe flight operations. In particular, it discusses what to do in emergencies. It deals with the procedures to be followed in the event of dangerous weather or fire. In addition, special dangers during take-off and landing and the topic of off-field landings are also discussed. Finally, other technical defects that can occur are discussed.
Dangerous weather conditions
This theory chapter deals with various aspects of visual flight and how weather conditions affect flight safety. It is emphasised that the ability to fly in bad weather depends not only on the current weather conditions, but also on the equipment of the aircraft and the training of the pilot. In particular, the challenges for private pilots under visual flight rules (VFR) in unfavourable weather conditions such as poor visibility, low cloud cover, freezing precipitation and thunderstorm fronts are highlighted.
The section explains the importance of complying with the visual flight minima defined by the legal regulations. It is emphasised that assessing the weather from the ground is sufficient for flights in the vicinity of the aerodrome, while professional flight weather preparation is necessary for longer flights.
Several examples of dangerous situations during visual flights in difficult weather conditions are given. The definition of a minimum safety altitude for various flight route sections and the importance of terrain structure and navigation accuracy in this context are also discussed.
It also covers the minimum visibility requirements for different airspaces and the challenges of navigating at low altitudes. The section emphasises the importance of guidelines, arresting lines and alternate aerodromes and discusses flights over clouds, including consideration of cloud cover and the availability of navigational aids.
A special focus is placed on snow/ice, thunderstorms and flights at night. It is emphasised that despite shorter days and often critical weather in winter, safe flights according to visual flight rules are possible if certain safety aspects are taken into account. These include the consideration of snow and ice, which can both impair visibility and have a negative impact on the aerodynamic properties and mass of the aircraft.
Low temperatures in winter can impair the functionality of engines and batteries. Methods for preheating aircraft engines are discussed. The contamination of aircraft on the ground by ice, frost or snow is also discussed, emphasising that even thin layers of frost or snow can have a significant negative impact on flight performance.
Aircraft de-icing is identified as critical to flight safety, with various methods proposed to remove ice and snow from the aircraft surface. In-flight icing is also recognised as a significant risk, with various measures to prevent or reduce ice build-up being discussed.
The section concludes with a discussion of the dangers of thunderstorms, including storms, turbulence, icing, heavy precipitation and hail, and emphasises the need to fly around thunderstorms over a wide area. It also emphasises the risks of loss of orientation and darkness during flight. Overall, this theory chapter emphasises the importance of careful flight preparation and consideration of specific winter conditions to ensure safety in visual flight.
Fire and smoke
Fire on board an aircraft is one of the most dangerous and time-critical situations in air traffic. It requires immediate action, whereby a distinction is made between two scenarios: Either the fire can be fought in flight or after a quick landing by specialised personnel on the ground. The chapter deals with different types and sources of fire and how to fight them. When smoke develops, the crew often has little time to act. Knowledge of how fires start and how to extinguish them is essential.
The most effective method of firefighting is the removal of fuel, heat or oxygen. Various extinguishing agents work by binding the oxygen or cooling. In aeroplanes, the options for fighting fires are limited. For example, the fire can be fought with a halon fire extinguisher on board, but with limited capacity. Knowledge of the fire classes is crucial for the correct use of extinguishing agents. In the event of a carburettor fire, which only occurs on aircraft with piston engines, the fire cock should be closed and the engine kept running so that the flames are sucked into the engine. In the event of an engine fire during flight, an immediate landing is usually the best option. Overheated brakes can lead to a fire hazard due to high or continuous loads. Immediate action must be taken in the event of smoke or fire in the cockpit, as this can have serious consequences for the technology and the crew. If a fire is suspected in the electrical system, it should be switched off immediately. In the event of a cable fire, the aircraft must be evacuated and the electrical system switched off.
Dangers during take-off and landing
The difficulties and special features of take-offs and landings, in particular the increased risks of wrong decisions and resulting flight accidents in these sensitive flight phases, are dealt with in detail in this chapter.
The condition of the runway plays a decisive role in ensuring a safe take-off and landing. Various factors such as vegetation, ground conditions, slope and contamination of the runway influence the rolling resistance, directional stability and structure of the aircraft. Aircraft manufacturers specify take-off performance under idealised conditions and any deviations from these conditions must be taken into account when calculating the take-off and landing distance.
Meteorological influences such as wind, wind shear, turbulence, precipitation and temperature can have a significant impact on flight conditions and require special attention from the pilot. These influences are particularly critical during the take-off and landing phase. Pilots must therefore familiarise themselves thoroughly with the current weather conditions and their development before every flight.
Wind shear, as sudden changes in wind direction and/or strength, is a serious source of danger, even for higher performance commercial aircraft. Turbulence caused by various factors such as convective air movements or airflow obstructions can impair flight performance and must therefore be avoided or handled with great care.
Temperature affects the performance of the aircraft, with cold air leading to better performance, while warm air reduces performance. Precipitation such as rain can disrupt the airflow on the wings and impair flight performance.
Finally, the sun, especially when it is low on the horizon, can also significantly impair visibility during take-off or landing.
Visual flight is based on the pilot's view from the cockpit in order to maintain the flight attitude, navigate, avoid collisions and recognise dangers at an early stage. Especially in the vicinity of aerodromes, a wide variety of road users such as motorised aircraft, gliders, parachutists or lighter-than-air aircraft can be expected. Particular caution is required in the vicinity of radio navigation systems and military low-flying areas.
Compliance with traffic regulations in accordance with the LuftVO is essential for safe air traffic. It is important that the aircraft with greater manoeuvrability gives way to the aircraft with less manoeuvrability. Sufficient distances must be maintained to avoid collisions. The visibility of your own aircraft can be increased by using collision warning lights and, if necessary, by switching on the landing lights. Radio communication supports the avoidance of dangerous approaches through early and clear communication.
Aerodromes harbour a high risk of accidents due to the high density of aircraft. Maximum attention is required when taxiing, especially at large and unfamiliar aerodromes. Wake vortices, especially from large aircraft, can have a considerable impact on smaller aircraft. The exhaust jet from engines and turbulence from helicopter rotors also pose risks.
Bird strike is another danger, especially near aerodromes and during bird migration. Measures such as scaring birds away by airfield operators or switching on landing lights can help to minimise the risk.
To summarise, it is crucial that pilots are always alert, follow rules and take proactive measures to ensure aviation safety.
Outlanding
An unscheduled landing may be necessary for various reasons, such as deteriorating weather, technical problems, health restrictions, fuel shortages or the onset of darkness. Such landings require that a suitable landing site is available, the suitability of which also depends on the urgency of the landing and the type of aircraft. Off-airport landings are not only possible at unusual landing sites, but also at regular airports, e.g. if you touch down in front of the runway threshold. By law, off-airport landings require either authorisation or a compelling reason, such as an engine failure.
If there is a risk of fuel shortage or deteriorating weather conditions, the decision to make an off-field landing should be made at an early stage in order to find suitable fields for the landing. Technical or health problems require a quick assessment of the situation in order to decide whether an off-field landing increases or decreases safety. In the event of an engine failure, preparations for an off-field landing must be started immediately and the speed of the best glide assumed. The landing field should be selected according to criteria such as length, wind direction, absence of obstacles, slope and surface characteristics. Harvested grain fields, large and flat areas that are in the direction of the wind and free of obstacles are particularly suitable.
The approach should be planned and executed using standard procedures and checklists. Occupants should buckle up with all available seatbelts and a decision should be made whether to open doors prior to landing. Touchdown should be at the lowest possible speed with the flaps fully extended. After landing, priority should be given to rescuing and caring for people. An ELT transmitter can automatically send out radio signals to determine the location after an accident.
In flight training, the ability to master various types of unscheduled landings is considered essential. These include forced off-field landings such as emergency landings and ditchings, which require quick action, as well as safety landings, which leave more room for manoeuvre. Every type of forced landing requires maximum concentration and quick, rational decisions.
A safety landing is a proactive measure to ensure safety in the absence of an emergency. It may be necessary due to various circumstances such as medical emergencies, instrument failures, deteriorating weather conditions or fuel shortages. The aim is to carry out the landing in a safe and controlled manner, ideally at an aerodrome.
An emergency landing, on the other hand, is a forced landing due to an acute danger, such as engine failure or fire on board. In such situations, there is little time for deliberation and the pilot's actions must be quick and effective. The emergency landing may require a forced landing or ditching.
A ditching is a special form of emergency landing that is relevant for flights over water. It requires special preparations and equipment such as life jackets and life rafts. During a ditching, it is crucial to choose the right technique for touching down in order to prevent the aircraft from rolling over and to maximise the occupants' chances of survival.
In all cases, it is important that the crew prepares for such scenarios, trains regularly and knows and can apply the necessary emergency procedures.
Possible technical defects
This section emphasises the importance of understanding and dealing with technical defects during flight. It is emphasised that some defects can have serious consequences. Correct diagnosis and prompt action are critical. Resources include flight manuals and instructions from manufacturers or maintenance organisations.
Particularly in the case of engine problems, the risk varies depending on the type of aircraft and the severity of the defect. While an engine failure in a multi-engine aircraft does not necessarily pose a serious threat, it can be critical in a single-engine aircraft.
Early detection of power loss during the take-off run enables a safe take-off abort. In the event of engine problems after take-off, a safe airspeed should be ensured immediately and a landing initiated if necessary.
Engine problems, such as carburettor icing or a drop in oil pressure, can occur during a cruise flight. Here, too, it is important to recognise the problem quickly and take appropriate countermeasures. In the event of critical problems, such as a sharp drop in oil pressure combined with an increase in oil temperature, an immediate landing is required.
Finally, restart procedures following in-flight engine failures are discussed, emphasising that these should only be carried out at safe altitudes and according to clearly defined procedures.
To summarise, the emphasis is on careful observation and maintenance of the engine, knowledge of the flight manual and immediate reaction to signs of problems to ensure the safety of the flight.
In addition to engine problems, other possible critical defects are landing gear and control problems, as they can cause considerable difficulties both during flight and on landing. Landing gear problems are particularly critical during landing, whereby a distinction is made between fixed and retractable landing gear. Retractable landing gear is more prone to failure due to its complexity. A comprehensive pre-flight check can recognise and avoid most problems in advance. In the event of control problems caused by mechanical or hydraulic faults, precise knowledge of the on-board systems is crucial for handling unexpected situations.
Technical defects such as electrical and instrument failure can also severely impair flight operations. A complete electrical failure, often caused by faulty connections or overloading, leads to the failure of various systems, which can make navigation and communication more difficult. Instrument failures, especially of flight and navigation instruments, require a high degree of flying skill and adaptability from the pilot. A radio failure also requires special procedures to ensure communication with air traffic control and other aircraft.
In all cases, good preparation, knowledge of the aircraft systems and careful pre-flight checks are essential to minimise such problems. In critical situations, it is important to remain calm, act systematically and consider a safety landing if necessary.
The chapter also highlights other potential dangers in aviation and shows professional strategies for coping with them. It shows that some risks, such as flying with a severe cold, are avoidable. Other challenges, such as navigating in marginal flight conditions, can be mastered safely through special training. In cases of deliberate hazards, such as sabotage, early detection through attentive observation of the surroundings is crucial. If this is not successful, the challenge remains to handle the situation as thoughtfully and professionally as possible.
Critical flight attitudes, such as a stall, are not necessarily dangerous as long as they are practised regularly under the guidance of a flight instructor. Unusual flight attitudes can be caused by turbulence, spatial disorientation or improperly executed flight manoeuvres. These can lead to high bank angles and speeds, which in turn risks overloading the aircraft structure and the human body. The ability to recognise such situations at an early stage and resolve them correctly is therefore of crucial importance.
The take-off, approach and landing phases of flight are particularly susceptible to stalls, as they involve flying at low speeds with varying configurations and high workloads. These phases leave little room for error, which is why the training of procedures for the early detection and termination of a stall is essential. It is important to know the limitations of each aircraft type as aircraft react differently.
In addition, disruptions on the ground and dangerous interventions are addressed. This includes problems that do not originate directly from the aircraft, such as the failure of ground equipment to which the pilot must react. Special airspaces and the failure of radio navigation systems also pose challenges that can be overcome through careful flight planning and NOTAM checks.
It also describes in detail the challenges and dangers of flying in mountainous terrain or at high altitudes. It emphasises the need to prepare for these special conditions and to act responsibly. Key topics include the effects of lower air density on aircraft performance and the human body, the particular importance of thorough flight preparation and the need to adapt to changing weather conditions in the mountains.
Firstly, the danger of oxygen deficiency (hypoxia) is emphasised, which can occur at altitudes of 5,000 ft and above. The symptoms of hypoxia vary from person to person and are influenced by factors such as fitness and smoking.
Special attention is paid to navigation in the mountains. It is emphasised that conventional navigation aids such as radio navigation systems are only of limited use in the mountains, while satellite navigation is more reliable. Terrestrial navigation along clearly recognisable valley courses is regarded as critical, as many valley entrances can be similar and in some cases end in dead ends.
Weather conditions in the mountains can change rapidly, with phenomena such as thermal and orographic turbulence being more pronounced. Strong downdrafts can exceed the performance limits of an aircraft. It is therefore essential to obtain thorough weather advice before flying in the mountains.
Pass overflights present a particular challenge, especially for aircraft with low performance or without oxygen equipment. It is recommended to approach passes at an angle of 45° in order to keep the possibility for turnarounds open. The service ceiling, i.e. the maximum altitude at which the aircraft can still achieve a climb rate of 100 ft/min, is also discussed. Flight routes that are close to the maximum performance of the aircraft should be avoided.
Finally, the topic of loading errors is addressed. An incorrect centre of gravity position can have a considerable influence on the flight characteristics. A centre of gravity that is too far back worsens the stall behaviour and increases the tendency to spin. A centre of gravity that is too far forward makes take-off, recovery and landing more difficult. Exceeding the maximum permissible take-off mass can lead to structural damage to the aircraft and increase the stall speed.