Apparatus and associated methods relate to determining, based on a spatial extent of ice accretion, a maximum size of super-cooled droplets contained in an atmosphere and/or if an atmosphere contains super-cooled water droplets that equal and/or exceed a predetermined size. A testing region on an exterior surface of an aircraft is monitored for ice accretion by an ice detector. A boundary calculator determines a specific location to be tested within the testing region. The determined specific location corresponds to a calculated boundary that separates an ice-accretion region from an ice-free region if the atmosphere contains super-cooled water droplets of no larger than the predetermined size. If the ice detector detects ice accretion at the determined specific location, an alert is generated. The alert can advantageously inform a pilot of the aircraft that the atmosphere contains super-cooled water droplets that equal or exceed the predetermined size.

An air data system includes a laser emitter, a laser receiver, and an electronics module. The electronics module includes a processor and computer-readable memory encoded with instructions that, when executed by the processor, cause the laser to emit a coherent light pulse into a target volume locating within an exhaust flow aft of an aircraft. The laser receiver detects backscatter produced by the coherent light pulse interacting with the aft target volume, and the electronics module determines an air data parameter based on the backscatter and at least one of an engine parameter indicative of an engine condition of the aircraft and an aircraft parameter indicative of a state of the aircraft before outputting the air data parameter to a consuming system of the aircraft.

Disclosed is a method of correcting at least one result of calculating at least one flight characteristic of an airplane, based on in-flight measurements and on values calculated from the measurements, the in-flight measurements being taken in at least one determined flight condition defining a determined flight point, each flight condition being defined by particular flight parameter values, the measurements and values being in particular: θ.sub.measure the measured pitch angle of the airplane and α.sub.model the angle of attack calculated by solving a lift equation and an aerodynamic model associating the angle of attack α of the airplane with at least one flight parameter, which is the lift coefficient Cz of the airplane. The pitch angle measurements θ.sub.measure are corrected by a pitch angle correction term Δθ.sub.0 that is a particular constant for each flight, and the calculated angles of attack α.sub.model are corrected by an angle of attack correction term Δα(Cz . . . ).

A wave generator for an ultrasonic air data system can be configured to collect data derived from a flow of air in a downstream direction. The wave generator can include an ultrasonic wave source configured to output ultrasonic waves from a first end and a wave shaper connected to the first end of the ultrasonic wave source. The wave shaper can be configured to focus the ultrasonic waves into an area downstream from the ultrasonic wave source bounded by a first plane parallel to the downstream direction and a second plane orthogonal to the first plane.

A first air data value is generated based on a first set of parameters. A second set of parameters that does not include any of the first set of parameters is processed through an artificial intelligence network to generate a second air data value. The second set of parameters is processed through a plurality of diagnostic artificial intelligence networks to generate a plurality of diagnostic air data values. Each of the plurality of diagnostic artificial intelligence networks excludes a different one of the second set of parameters. One of the second set of parameters is identified, based on the first air data value and the plurality of diagnostic air data values, as a fault source parameter that is associated with a fault condition.

An aircraft air data probe contamination monitor includes at least two air data sensor probes, a first probe located on one side of the aircraft, a second probe located on an opposite side of the aircraft, each probe being operable to generate a parameter value from an airflow passing the in-flight aircraft. The monitor also includes a processor operable to compare the generated parameter value from the first probe to the generated parameter value from the second probe to determine if one of the first probe and the second probe is contaminated.

An air data system includes an avionics system and a plurality of sensors associated with the avionics system, each of the sensors providing a signal indicative of a parameter used by the avionic system to determine the flight status of the aircraft. At least one air data probe is electronically coupled to the avionics system. At least one pitot static probe is coupled to a pressure transducer through pneumatic tubing, the pressure transducer is electronically coupled to the avionics system.

Estimating the speed of an aircraft estimates three components of the speed vector (TAS, AOA, SSA) of an aircraft relative to the surrounding air. The static pressure is estimated on the basis of measurements of geographical altitude. A first intermediate variation of a linear combination of the three components of the speed vector of the aircraft relative to the surrounding air is estimated using explicitly the fact that the pressure measured by the static probe is falsified by a known quantity under the effect of the three components of this speed vector of the aircraft relative to the surrounding air. The process then estimates the three components of the speed vector of the aircraft relative to the air by likening the latter to the speed vector of the aircraft relative to an inertial reference frame and by using inertial measurements. The various estimates are fused to provide a final result.

An air data probe includes a probe head having an interior surface defining a cavity, a component positioned within the cavity of the probe head, a plurality of protrusions defining contact between the interior surface of the probe head and a peripheral surface of the component prior to brazing the component to the probe head, and a braze material located between the interior surface of the probe head and the peripheral surface of the component as a result of brazing the component to the probe head.

A flow angle sensor includes a sensing element, a background component connected to and movable with the sensing element, the background component having a marker, a lens adjacent the disk, an image sensor axially aligned with the lens, a light source positioned to illuminate the disk, and an image processing system connected to the image sensor. The image processing system provides an angle of attack output based on a location of the marker sensed by the image sensor.