Methods, systems, and devices for wireless communication are described. Generally, the described techniques provide for determining a suitable pattern for transmitting reference signals used for positioning on allocated resources. In particular, the pattern may be used to assign the reference signals to frequency tones across multiple symbols such that the frequency tones to which the reference signals are mapped in at least two consecutive symbols are non-adjacent (e.g., separated by at least one frequency tone). In some cases, a wireless device may determine the pattern used to assign reference signals used for positioning autonomously (e.g., based on configured algorithms or a look-up table), and, in other cases, a wireless device (e.g., a user equipment (UE)) may determine the pattern used to assign reference signals used for positioning based on a configuration received from another wireless device (e.g., a base station).

Disclosed is a method including sampling the air of a pressurized zone of an aircraft by identifying a pre-existing pressurized air flow in a pressurized zone of an aircraft without substantially blocking the pre-existing pressurized air flow and creating a data record that can be used when cleaning the cabin air ducts using cleaning techniques suitable for cleaning the respective air duct elements using a sequence of cleaning acts suitable for cleaning select elements of the cabin air ducts. The data record includes identification information which can be used to report incidents to the relevant aviation authority.

A device that equalizes an aircraft pressure difference has a separating wall, fixable to the aircraft, and a decompression valve. The wall is for fluidically separating first and second spaces, and has a flow opening that fluidically connects the spaces. The valve closes the flow opening. A securing element on the valve or wall enables a release of the valve when a pressure gradient between the spaces is exceeded, such that there is a fluidic connection between the spaces. The receiving element on the wall or valve is connected to the receiving element. The securing element has a rotary element and fixing elements. The rotary element is rotatably mounted about a rotational shaft. The rotary element is receivable in the receiving element. The fixing elements non-rotatably fix the rotary element beneath the predetermined pressure gradient. At least one of the fixing elements is a spring.

A device that equalizes an aircraft pressure difference has a separating wall, fixable to the aircraft, and a decompression valve. The wall is for fluidically separating first and second spaces, and has a flow opening that fluidically connects the spaces. The valve closes the flow opening. A securing element on the valve or wall enables a release of the valve when a pressure gradient between the spaces is exceeded, such that there is a fluidic connection between the spaces. The receiving element on the wall or valve is connected to the receiving element. The securing element has a rotary element and fixing elements. The rotary element is rotatably mounted about a rotational shaft. The rotary element is receivable in the receiving element. The fixing elements non-rotatably fix the rotary element beneath the predetermined pressure gradient. At least one of the fixing elements is a spring.

An aircraft cabin blower system includes a transmission configured to receive mechanical power from a gas turbine engine in the form of a first transmission input; and an electrical circuit including a first electrical machine, a second electrical machine, and power management system, wherein, when operating in a blower mode, the first electrical receives mechanical power from the gas turbine engine and act as a generator to provide electrical power to the power management system, and the second electrical machine acts as a motor providing mechanical power to the transmission in the form of a second transmission input, the second electrical machine being driven by electrical power from the power management system. The transmission's output drives a cabin blower compressor when operating in the blower mode, a speed of the output of the transmission being determined by a function of a speed of the first and second transmission inputs.

An aircraft cabin blower system includes a transmission configured to receive mechanical power from a gas turbine engine in the form of a first transmission input; and an electrical circuit including a first electrical machine, a second electrical machine, and power management system, wherein, when operating in a blower mode, the first electrical receives mechanical power from the gas turbine engine and act as a generator to provide electrical power to the power management system, and the second electrical machine acts as a motor providing mechanical power to the transmission in the form of a second transmission input, the second electrical machine being driven by electrical power from the power management system. The transmission's output drives a cabin blower compressor when operating in the blower mode, a speed of the output of the transmission being determined by a function of a speed of the first and second transmission inputs.

The invention relates to a system for environmental control of an aircraft cabin (5), comprising a device for bleeding compressed air from at least one aircraft engine; an air cycle turbine engine (20) comprising at least one supercharger (21) connected to said device for bleeding compressed air by an air bleed duct (7) and a turbine (22) connected to the cabin (5) by a cabin inlet duct (8) in order to be able to supply said cabin with air at a controlled pressure and temperature, characterised in that it further comprises: stationary blading (23) which has a variable injection cross section and is mounted on said turbine (22) of said air cycle turbine engine (20) so as to be able to modify, on command, the flow rate and/or the pressure of air supplying an air inlet of said turbine (22); and a second supercharger (22) which is mounted on said air cycle turbine engine (20) and is connected to a device for bleeding outside air and to said bleed duct.

The invention relates to a system for environmental control of an aircraft cabin (5), comprising a device for bleeding compressed air from at least one aircraft engine; an air cycle turbine engine (20) comprising at least one supercharger (21) connected to said device for bleeding compressed air by an air bleed duct (7) and a turbine (22) connected to the cabin (5) by a cabin inlet duct (8) in order to be able to supply said cabin with air at a controlled pressure and temperature, characterised in that it further comprises: stationary blading (23) which has a variable injection cross section and is mounted on said turbine (22) of said air cycle turbine engine (20) so as to be able to modify, on command, the flow rate and/or the pressure of air supplying an air inlet of said turbine (22); and a second supercharger (22) which is mounted on said air cycle turbine engine (20) and is connected to a device for bleeding outside air and to said bleed duct.

Example implementations for maintaining airflow into a flight deck of an aircraft are described herein. An example method may involve detecting, at a computing system and using a flow sensor, a decrease in a level of airflow entering into the flight deck such that the level of airflow is below a threshold level. The aircraft may include air sources configured to direct airflow towards occupancy areas (e.g., the cabin and flight deck) of the aircraft. The method may further involve adjusting a control valve to cause an increase in the level of airflow entering into the flight deck based on detecting the decrease in level of airflow entering into the flight deck. The control valve may be configured to enable and disable airflow from entering into the flight deck.

Example implementations for maintaining airflow into a flight deck of an aircraft are described herein. An example method may involve detecting, at a computing system and using a flow sensor, a decrease in a level of airflow entering into the flight deck such that the level of airflow is below a threshold level. The aircraft may include air sources configured to direct airflow towards occupancy areas (e.g., the cabin and flight deck) of the aircraft. The method may further involve adjusting a control valve to cause an increase in the level of airflow entering into the flight deck based on detecting the decrease in level of airflow entering into the flight deck. The control valve may be configured to enable and disable airflow from entering into the flight deck.