Abstract: A computer-implemented method, environmental control system (ECS) for an aircraft, and system are provided. Air temperatures at the inlet and outlet of a ram air duct for an ECS are measured. Also, air temperatures at outlets from one or more heat exchangers arranged in the ram air duct are measured. The temperatures are typically measured when the aircraft is on the ground and when aircraft engines supplying air to the ECS are operating at idle. Shortly thereafter, the heat exchangers are manually inspected to determine a level of actual fouling (e.g., dirt, dust, or other debris accumulated on heat exchanger surfaces). A supervised machine learning or other statistical analysis is performed on the measured temperatures and associated actual fouling levels to develop a model that predicts an amount of heat exchanger fouling, based on the temperature measurements. An alert can be output if the predicted fouling exceeds a fouling threshold.

Abstract: A computer-implemented method, environmental control system (ECS) for an aircraft, and system are provided. Air temperatures at the inlet and outlet of a ram air duct for an ECS are measured. Also, air temperatures at outlets from one or more heat exchangers arranged in the ram air duct are measured. The temperatures are typically measured when the aircraft is on the ground and when aircraft engines supplying air to the ECS are operating at idle. Shortly thereafter, the heat exchangers are manually inspected to determine a level of actual fouling (e.g., dirt, dust, or other debris accumulated on heat exchanger surfaces). A supervised machine learning or other statistical analysis is performed on the measured temperatures and associated actual fouling levels to develop a model that predicts an amount of heat exchanger fouling, based on the temperature measurements. An alert can be output if the predicted fouling exceeds a fouling threshold.

Abstract: Method and apparatus for determining a probability of below-specified performance of a low temperature limit control valve. During operation of an environmental control system (ECS) for a vehicle, current operation parameters related to the ECS are sensed. Historical operation parameters related to the ECS are retrieved. A probability of below-specified performance of the low temperature limit control valve is determined based on a predetermined relationship between the stored current operation parameters, the historical operation parameters, and the probability of below-specified performance of the low temperature limit valve.

Abstract: A computer-implemented method, environmental control system, and aircraft are provided. Environmental operating conditions data for a heat exchanger is received. Measured values from sensors measuring parameters of the heat exchanger are also received. An operating model for the heat exchanger based on the received environmental operating conditions is retrieved from a first data structure. The retrieved model includes estimated values for the sensors. A difference between the estimated values and the measured values is calculated. The calculated differences are compared to at least one threshold value. Upon the differences exceeding the at least one threshold value, the calculated differences are compared to abnormal operation models in an abnormal operation library data structure. Upon the calculated difference matching an abnormal operation model in the abnormal operation library data structure, outputting an abnormal operation identity associated with the abnormal operation model.

Abstract: A system and method for transmitting an information signal through a radio-frequency opaque barrier are disclosed. A transmitter is positioned on a first side of the barrier and a re-transmitter is positioned on a second side of the barrier. The transmitter includes a controller that modulates a received information signal with a carrier signal and forwards the modulated information signal to a vibration generator which converts the received electrical signal to a corresponding vibration signal. The re-transmitter includes an accelerometer that detects vibration signals and produces a corresponding electrical signal and a controller coupled to the accelerometer which receives the electrical signal from the accelerometer and demodulates the information signal included within the electrical signal received from the accelerometer.