Abstract: A method of approximately correcting a vehicle's guidance system command for the disturbing effects of the medium through which it is moving, without having to sense or estimate the speed and direction of that medium. The correction is determined by taking the ratio of two scalar quantities: the speed of the vehicle relative to the medium, which can be estimated from the known fluid dynamic characteristics of the vehicle, divided by an approximation of inertial speed, which can be obtained using one or more on-board sensors such as a GPS, thus increasing transient performance of the vehicle moving through the fluid medium.

Abstract: A method of approximately correcting a vehicle's guidance system command for the disturbing effects of the medium through which it is moving, without having to sense or estimate the speed and direction of that medium. The correction is determined by taking the ratio of two scalar quantities: the speed of the vehicle relative to the medium, which can be estimated from the known fluid dynamic characteristics of the vehicle, divided by an approximation of inertial speed, which can be obtained using one or more on-board sensors such as a GPS, thus increasing transient performance of the vehicle moving through the fluid medium.

Abstract: A method of guiding aerial vehicles to a target site in adverse weather conditions wherein the method regulates the range indirectly by regulating heading error to an offset target that revolves around the true target site. The improved guidance architecture is effective in adverse weather conditions, such as high winds.

Abstract: A method of computing an antenna pointing direction for an inertial navigation unit (INU) utilizing a global positioning system (GPS) signal during periods of GPS signal outage includes determining antenna pointing error of magnitude and phase information. The phase information is obtained by detecting the angle where a signal to noise ratio of the antenna passes through a minimum level, and wherein the magnitude information is obtained by calculating the difference between the maximum and minimum signal to noise ratio of the antenna measured over one conical cycle of rotation of the antenna about an axis that is not parallel to a vector pointing from an antenna center to a GPS signal transmitting satellite. During periods of GPS signal outage, the determined magnitude and phase information is used to cause a nominal antenna beam axis to move by an amount that depends on the determined magnitude information in a direction defined by the determined phase information.

Abstract: A multimodal vehicle includes a ground based vehicle with an attached high-capacity airfoil parachute for deployment. The ground based vehicle includes a drive system for use on either land, water or both. Furthermore, the ground based vehicle is sized and dimensioned for transport of multiple vehicles in a cargo plane. The high-capacity airfoil parachute allows high-altitude deployment of the multimodal vehicle. The risers to the parachute may be adjusted for powered parachute flight rather than free fall flight. The ground based vehicle may include a propeller for powered flight.

Abstract: The canopy of the ram air parachute of the present invention has cells which are trapezoidal in shape. The non-loaded ribs of the canopy are shorter in height than the loaded ribs. The different height ribs results in tensioning of the bottom skin and transfer of forces from the loaded rib-bottom skin junction through the bottom skin to the non-loaded rib. The non-loaded rib is then tensioned to not float up as high. Thus, the spanwise distortion of the top skin is reduced and the aerodynamics are improved.

Abstract: A fastening system particularly suited for removably securing a first component of a parachute system to a second component. The fastening system includes a first and at least a second magnetic element secured to the first and second components of the parachute system. At least the first magnetic element is adapted to create a magnetic field that attracts the second magnetic element. In the preferred embodiment, both the first and second create magnetic fields which attract each other and may include permanent magnets or temporary magnets. Alternatively, the magnetic elements may include electromagnets connected to a power source. Optionally, a power controller adjusts the strength of the magnetic force generated by the magnetic elements.

Abstract: A ram air parachute of the present invention includes specific cross porting of the ribs between certain cells to create a two-stage or multi-stage deployment. Cross ports between certain sets of cells have reduced or no conductance. In this manner, the center cells of the canopy open first, slowing decent, before the outer cells. The staged deployment reduces the opening forces on the pilot particularly in high speed flights.