PAPERS, PATENTS, AND SUPPLEMENTAL RESOURCES

SUPPLEMENTS (papers in review) 

Pap H:  Ground Effect Flight Transit (GEFT) - Approaches to Design (PREPRINT)

• 3D CFD studies on impact flat plate and thin-plate cambered airfoils provide insight into how to attain high L/D efficiency in ground-effect flight.
• L/D efficiencies greater than 40 were only attainable if the forward section generated thrust due to air flow, this is referred to as “induced thrust”.
• Thin cambered airfoils achieved L/D greater than 40 in ground effect, but it is possible for pressures around the leading edge to create included drag rather than reduced thrust.
• An airfoil with a cambered upper surface, horizontal lower surface, and trailing flap (aka, Airfoil B) was able to systematically achieve L/D in excess of 60 in close ground effect.
• Airfoil B achieved L/D in excess of 50 when used in a 3D lifting body without enhancement from upper surface propulsion

Pap I:  Ground Effect Flight Transit (GEFT) - Towards Trans-Modal Sustainability (PREPRINT)

• An airfoil with a cambered upper surface, horizontal lower surface, and trailing flap (aka, Airfoil B) was compared TO a previous benchmark as a lifting body design for fuselage, Airfoil B performed better than any previous airfoils.
• The 3D digital prototype of Airfoil B attained an L/D of 38.9 without propulsion enhancement, and greater than 50 with propulsion enhancement.
• A horizontal upper surface followed by a propulsor and a trailing taper (aka, Lift Span Tech) was an effective upper surface configuration for generating high L/D where the propulsor created induced thrust.
• At higher thickness ratios boundary layer separation occurred over the trailing taper, increasing the propulsor power alleviated the boundary layer separation.
• These results were translated to viable vehicles based on the corridor, with corridors including railway, subway, highway, and waterway corridors.  A range of viable modes of operation were identified with L/D in excess of 40, many in excess of 50.

Pap J: Ground Effect Flight Transit (GEFT) in Subways (PREPRINT)

• GEFT transit in tunnels has an advantage of higher upper surface lift pressures than ground-effect alone.
• A problem encountered with GEFT transit in tunnels as low clearances is the drag induced by pushing air through the tunnel.
• In tight clearances, it was difficult to attain L/D in excess of 25.
• However, a cost analysis of the energy needed at L/D of 20 and 30 identified that energy costs were an order of magnitude less than car-related costs, like parking in cities, and an oRder of magnitude less than a reasonable time-value of money if GEFT technology were able to provide non-stop transit at high speeds.
• A worthy goal is GEFT technology that can convert one subway train track to two GEFT tracks (due to reduced height) and thus enable non-stop transit from origin to destination throughout subway networks with transmodal connectivity to other corridors.n progress.  ETA August 7, 2024.

Data Management Policy - HS-Drone LLC is a patent and license company, promptly  filing patent applications then publishing results, seeking collaboration to commercialize.  

Patent Applications PCT/US24/35242;  Entitled: “Ground Effect Aircraft” (June, 2024)

• Summarizes 18 months of innovation including priority provisional patent applications of the dates: 6/25/2023, 8/1/2023, 8/16/23, 8/30/23, 9/29,23, 11/3/23, 12/3/23, 12/29/23, 2/15/2024, and 5/20/24.
• Provides 32 charts/drawings of aircraft embodiments and performance results.
• Provides patent claims on ground-effect vehicle configuration, Lift-Span Technology, and the cross-over propulsor.
• Provides a Specification enabling continuation-in-part or divisional patent applications on technologies of: Bernoulli Loops, Control Algorithm for Ground-Effect Aircraft, Solar Aircraft with Bifacial Panel Lifting Body Surface, Railway Tracks with Lift-Enhancing Walls, Novel Towed Platform Aircraft, and Fan Configuration with Focusing Discharge.
• Provides concisely stated illustrative examples in paragraph 110a-n. 

BENCHMARKS Paper Entitled, “New Benchmarks in Ground-Effect Flight Energy Efficiency” (July, 2024)

• Relates L/D efficiencies to published energy-per-passenger-mile efficiencies to provide basis for comparing GEFT digital prototype performances to established trademarks.
• GEFT defined at HS-Drone’s Ground Effect Flight Transit which are vehicles with hovercraft-like compartments capable of L/D efficiencies up to 300% more than airliners.
• GEFT are designed as low aspect ratio vehicles.
• Summarizes the most complete “Methods” section published by authors to date.
• Documents key combinations of innovations capable of exceeding 30 L/D.
• Identifies work in progress and paths forward to expand GEFT applications capable of L/D in excess of 40, 50, and 60.

TRB Paper Entitled, “Highly-Efficiency Low-AR Aerial Vehicles in Urban Transit” (Jan 8, 2024)

• New theory on aerodynamic lift is introduced
• Bridging gap technologies Identify path to merge air and ground transit
• Expanded realm of solar-powered aircraft mapped on image
• Bernoulli loops introduced as bridging and transition technology to hyperloop

TRB Poster (Jan 8, 2024)

• Summarizes TRB Paper (above) and expands upon the concept of “trans-modal” transit where GEFT vehicles are able to seamlessly transfer between railway, subway, highway, and waterway corridors at high L/D efficiency and attain free flight as necessary. 

Supplement #1 Paper- (Submitted Dec-2024 ), “Camber”

“Understanding Thin Cambered Airfoils and their Solar Aircraft Applications”

Trends provide insight into heuristics on how air flow leads to lift pressures, later to be called “The Axiom”.

• Key to high L/D for cambered airfoils is low enough pitch to provide a continuous high pressure region on lower surfaces from leading edge to trailing edge.
• From an airfoil pitch of about 4°, the pitch can be decreased to increase L/D, where L/D will increase until a lower pressure region forms on the lower surface immediately behind the lead edge.
• A good leading edge shape is that of the NACA equation for the front of a NACA airfoil and as scaled to the thickness of a thin cambered airfoil. 

Supplement #2 Paper – (Submitted Dec-2024), “Sources”

“Thermodynamic Analysis of Distributed Propulsion”

• Lift-Span Technology is introduced where the preferred surface in front of a trailing-section propulsor is a morphing surface with surface pitch decreasing with increasing propulsor power.
• Aft a trailing-section propulsor, the surface pitch can be decreased to balance higher pressure discharge from the propulsor with lower pressure generated by air diverging from a surface, a good objective is to balance these opposing forces to attain near-free-stream pressure on the trailing edge taper.
• Of six propulsor positions evaluated based at 2 (upper and lower) X 3 (leading edge, midsection, trailing edge), best L/D and lift increase was generated by a trailing-edge upper-surface propulsor while the midsection upper surface propulsor had trends identifying utility to improve performance.
• One beneficial application of an upper-surface midsection propulsor is as a crossover propulsor.

News Release (Jan. 6, 2024)

& Initial Flying Railcar Paper Submission (2/15/2024)

Paper Entitled, “Ground Effect Railcar” (Feb, 2024) 

CFD results identify ultra-high efficiencies as viable on rails due to low air gaps and rails which block lateral losses of lift forces with the following needed to achieve the highest L/D:

• · Using fences and a trailing flap to block lift losses.
• · Engaging fences with rail to operate at low clearance gaps resulting in high L/D efficiency.
• · Optimizing/maximizing induced thrust for the frontal section.
• · Using distributed propulsion to increase lift on upper surfaces, increase induced thrust, and increase L/D.
• · An approach emphasizing 90% to 99% aerodynamic lift suspension with rubber tires to stay on tracks provides quieter, faster, and more-efficient operation rail service with full compatibility with existing rail infrastructure.
• · 3D simulations project L/D in excess of 60 are possible with non-optimized designs
• · A hypothesis emerges on the maximum lift coefficients that are possible which creates guidelines on weight distribution.
• · Performance trends are not projected by past “theories” of lift, but are predicted by new axiom.
• · Vertical movement of fence sections is introduced as a control methodology. 

BOOKS

Fixing Airplane Science - If only we would have known (Booklet, see Amazon Kindle)

Fixing Airplane Science - Ground effect aircraft (Booklet, see Amazon Kindle)

Fixing Airplane Science - Analogies versus basic physics (Booklet, see Amazon Kindle)

PAPERS IN REVIEW

“Kinetic Theory of Gases Explanation of Aerodynamic Lift”, submitted May, 2024:

• · New Theory on aerodynamic lift is elevated to the “axiom” status with mutually validating explanations by continuum and discrete mechanics and accurate performance extrapolation.
• · Axiom consists of heuristics for generating and expansion of aerodynamic lift based on converging and diverging air flow with pressure expansion at the speed of sound.
• · Reversible stages of aerodynamic lift identified in streamline paths which set stage for systems analysis of aircraft to identify lost work.
• · Impact of boundary layer separation is described in terms of impacting/diverging air flows and destruction of energy reversibly stored in stratified streamlines.

“Thin Cambered Lifting Bodies in Ground Effect Flight”, submitted, May 2024

• For thin cambered panel sections, L/D correlates with frontal-projected height rather than the thickness of the panel.
• Use of distributed propulsion can overcome “chord” requirement trends where L/D correlates with thickness rather than chord length (Supplement #2 is a critical resource).
• While higher-camber thin-plate airfoils (i.e., cambers greater than 0.04)  have little or no utility in contemporary aircraft, they are a strategic technology for ground effect aircraft due to the ground and fences blocking loss of lower-surface lift pressures.
• Middle thin cambered panel sections of a lifting body can replace laterally-extending wings for ground-effect flight as a light-weight lift-generating surface.
• Crossover sources that top off the dynamic pressure of oncoming air to pressurize the lower surface compartment are effective to increase lift at lower velocities in a format that can transition to optimal cruising velocities where air’s dynamic pressure is sufficient to create full suspension (Supplement #2 is a critical resource).
• Thin cambered middle sections are able to increase size of vessels to thicker/higher lifting body airfoil sections and lower fractions of fence perimeters which can both increase L/D efficiency and reduce vehicle weight per planform area; this latter quality teaches toward fully solar-powered WIG aircraft.
• The performance of thin cambered panel sections varies considerably based on designs that project higher pressure on lower surfaces of frontal sections; an understanding of this phenomenon is critical to attain the benefits of use of thin-cambered panel sections (Supplement #1 is a critical resource).
• For a well-designed lifting body, the Clearance Ratio is able to replace the Gap Ratio as the parameter that correlates with high L/D; this enables higher L/D due to a variety of factors as identified by other highlights.

PAPER IN TRANSITION

Paper Entitled, “Next Generation Ground-Effect Aircraft and the New Axiom of Aerodynamic Lift Enabling Their Conception” (May 2024)

A new WIG-aircraft planform is introduced with the following advantages:

a robust, barge-like geometry for survivability in choppy ocean waters—the design does not rely on lateral wing extensions, which are not designed to handle impacts from waves. 

• · A rectangular planform with decreasing perimeter fence/flap area with increasing scale allows for the simultaneous advance of both increasing thickness and decreasing air gap since inadvertent contact of a fence with water has less of an impact on a larger vessel. 
• · Increasing efficiency enables lower-cost more-robust electric propulsion, especially at speeds less than 0.6 Mach which would be favored in maritime transit. 
• · Further increases in efficiency with increasing surface area enable use of direct solar power to replace costs and weights of batteries and internal combustion engines. 
• · Key design parameters of “pusher” distributed propulsion are introduced to reduce chord length and focus on optimal designs.
• · The concept of concave lower compartments is introduced, but not to the extent of extensive use of thin cambered panels as midsections of aircraft.
• · Two ways to increase L/D efficiency: 1) decrease the gap and 2) increase the thickness. 
• · The 3D performance of a lifting body is able to approach, but not reach, 2D performance as the Clearance Ratio approaches zero with fences in application.