US 4,836,019 A · Compact air data sensor

Abstract

An air data sensor comprising an elongated probe having a standard, sharped edge, orifice pitot port or opening, and a tapered leading end that is elongated with respect to its lateral dimensions along the longitudinal axis of the probe. The leading end portion blends into the main portion of the probe at a desired relatively short distance downstream from the pitot port. The probe comprises a tube or barrel that can be rectilinear or circular in cross section. Sets of sensing ports are utilizied and at least one pair of ports is oriented on a common axis and facing in opposite directions. Reliable sensing can be obtained when two sets of oppositely facing ports are used with the axis of each set 90.degree. to the axis of the other set. By using the pressure sensed in more than one combination, that is by co-using the pressures, static pressure, impact pressure, angle of attack and angle of sideslip can be derived. The ports are positioned on the tapered forward section, rearwardly of the pitot port before the full size of the basic tube is reached, and are positioned very close to the leading end. The tapered forward section expands from the edge of the pitot port a short axial distance, not generally more than eight equivalent radii at the port location, and the ports are positioned greater than one and less than six equivalent radii aft of the pitot tip.

Claims21

Dependent claims

A longitudinally shortened pressure sensing probe comprising a barrel having first and second ends, means for supporting the second end of said barrel relative to an air vehicle in a desired orientation, said barrel having a longitudinal axis, and the first end of said barrel having a tapered leading end section, said tapered leading end section being generated about said longitudinal axis and extending for an axial length of not substantially greater than six times the minimum lateral dimension of a main part of said barrel downstream of the tapered leading end section measured perpendicular to said longitudinal axis;

a pitot port defined in the barrel and opening at a leading end of the tapered leading end section, said pitot port being defined by surface means extending at an angle with respect to the longitudinal axis to form a sharp peripheral edge on the pitot port, the surface tapering toward the axis in downstream direction;
a plurality of port means formed through the tapered leading end section ahead of the junction of the tapered leading end section and the main part of the barrel, said port means comprising at least two oppositely facing ports means that are centered on axes perpendicular to the longitudinal axis of the barrel, with the port means sensing pressures on opposite sides of the barrel, the common axis being oriented in a desired manner when the barrel is mounted on an air vehicle;
and
said leading end section comprising an enclosing surface formed so that cross sections taken through the longitudinal axis show the enclosing surface to have a longitudinal axial length of at least 11/2 times the minimum radial dimension at the location of the port means and to smoothly expand throughout the longitudinal length of the tapered leading end section.

1 more element

An air data sensing probe for determining air data parameters relative to the direction of fluid moving past the probe comprising an elongated probe barrel having a longitudinal axis, a first end of said barrel comprising a leading end with respect to the direction of fluid flow and comprising a tapered leading end section tapering to smaller size than a main part of the probe barrel in direction facing the fluid flow, said tapering section extending a relatively short length, but greater than one equivalent radius of the main part of the probe barrel and said tapered leading end section defining a circular pitot port facing in the direction of fluid flow and centered on the longitudinal axis;

a plurality of port means formed through the probe barrel on the tapered leading end section, said port means being arranged in at least two pairs with each of the port means in each pair facing in an opposite direction and generally centered along a common axis passing through the longitudinal axis of the probe barrel;
a manifold assembly mounted within said probe barrel and having a central passageway therethrough in fluid communication with the pitot port, and having a separate longitudinally extending passageway aligned with and opening to each of the port means to carry the pressure sensed by the respective port means to a second end of the barrel, said passageways each being fluidly isolated from the other passageways;
and
means for providing signals representative of the pressures at each of said pitot port and said port means, including means for providing a signal representing differential in pressure between selected port means for providing outputs from the probe.

1 more element

Dependencies are inferred from the claim text.

Compact air data sensor

Life of this patent

Compact air data sensor

Life of this patent

Abstract

Claims21