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This paper attempts to assess the benefits of a unique distributed propulsion concept, known as the Multi-Gas Generator Fan (MGGF) system, over conventional turbofan engines on civilian vertical takeoff and landing (VTOL) applications. The MGGF-based system has shown the potential to address the fundamental technical challenge in designing a VTOL aircraft: the significant mismatch between the power requirements at lift-off/hover and cruise. ...The MGGF-based system has shown the potential to address the fundamental technical challenge in designing a VTOL aircraft: the significant mismatch between the power requirements at lift-off/hover and cruise.

Two types of service are recognized: metropolitan area service, connecting airports with downtown and suburban heliports -- which will continue to be done by helicopters; and inter-city downtown to downtown service employing high speed future type VTOL aircraft. Currently operating VTOL airlines are demonstrating the practicality of metropolitan area helicopter service. ...The objective of this paper is to show the probable composition of the VTOL Transportation System of the future and provide some specific predictions concerning some of its key elements. ...Advanced, high speed VTOL vehicles, introduced in the 1970’s will make extension of current routes possible to inter-city service.

Advance study is vitally necessary in the fields of VTOL/ STOL performance.stability and control, and instrumentation and/ or displays for terrain clearance and avoidance during high speed, low altitude flight.

Jet powered VTOL aircraft with high performance capabilities are feasible and are being developed. Because operation of these vehicles within the low speed flight regime is mandatory, if the VTOL capability is to be realized, possible operational difficulties within this zone must be investigated from a safety standpoint. ...Because operation of these vehicles within the low speed flight regime is mandatory, if the VTOL capability is to be realized, possible operational difficulties within this zone must be investigated from a safety standpoint. ...The low speed flight regime as it applies to jet powered, VTOL, high performance aircraft is presented in comparison to similar zones existing for present day rotorcraft.

A cost-benefit analysis is presented which indicates that a VTOL business aircraft would be more viable economically than a contemporary turbine-powered business aircraft. ...A discussion of operational aspects of interest to future users of V/STOL business aircraft by a NASA test pilot with VTOL research aircraft experience is centered around the requirements for routine IFR terminal area operations.

The following types of vehicles were considered as competing: seaplanes, helicopters, VTOL, ekranoplans and patrol vessels. The results of the carried out comparisons have shown the capacity of work of the method and its sensitivity to all of the important mentioned above factors.

In particular, a hazard and risk analysis tool exploiting Bayesian belief networks was developed and demonstrated in support of the interim flight clearance process for the the JACKAL VTOL UAS platform being developed for use in Naval Research Laboratory research flight testing.

This paper is a preliminary step in the direction of the definition of a radically new wing concept that has been conceived to maximize the lift even at low speeds. It is expected to equip new aerial vehicle concepts that aim to compete against helicopters and tilt rotors. They aim achieving very good performance at very low speed (5 to 30 m/s) by mean of an innovative concept of morphing ducted-fan propelled wing that has been designed to maximize the lift force. This paper presents an effective bibliographic analysis of the problem that is a preliminary necessary step in the direction of the preliminary design of the wing. A preliminary CFD evaluation allows demonstrating that the claimed results are in line with the initial expectations. According to the CFD, results it has been produced a preliminary energetic evaluation of the vehicle in a flying car configuration by EMIPS method.

The different features and characteristics of seven varieties of VTOL aircraft are defined and discussed. Basically, the future for all VTOL vehicles hinges on the recognition of the need to select the proper type for a specific role. ...Compounding the two, he predicts very high cost for a highspeed VTOL. Thus the development of the low-speed helicopter necessarily emerged first. Although the evolution of VTOL vehicles has been slow and difficult, progress continues toward the original goal of a safer more effective vehicle for transportation through the air. ...Although the evolution of VTOL vehicles has been slow and difficult, progress continues toward the original goal of a safer more effective vehicle for transportation through the air.

The first powered vertical flight was accomplished less than four years after the first powered horizontal flight was made by the Wright Brothers. But it was not until nearly 30 years later that the first practical vertical takeoff and landing aircraft was flown. By World War II, the problem of achieving practical vertical flight had been solved with the introduction of the helicopter, but higher speeds were desired. Vertical and/or Short Take-Off and Landing (V/STOL) aircraft are intended to combine the vertical take-off and landing capability of the helicopter with the high forward speed of an airplane. The key problems with developing a practical vertical take-off and landing aircraft have been the same as with the early fixed-wing aircraft: high thrust to weight and adequate controllability. This paper looks at the key achievements in vertical flight throughout the 20th century.

Electric vertical take-off and landing (eVTOL) is defined as vertical lift aircraft propelled by electric power and capable of carrying people. Based on the system of battery powered CY300 eVTOL, a fuel cell-battery hybrid system (FBHS) in steady-state operation as a potential propulsion system for CY300 eVTOL is proposed. In order to analyze the feasibility of FBHS-powered eVTOL system, a mathematical model is established to evaluate the proposed system performance considering various irreversible effects. Furthermore, considerable sensitivity analyses indicate that the payload of the proposed system is considerably benefited by a higher specific energy of the battery system, specific power of the fuel cell system and hydrogen storage ratio of the hydrogen tank. Hydrogen tank weight decreases the payload while enhances the hovering time.

The STOL capability includes a deck run of no more than 400 feet, while retaining an excellent vertical takeoff and landing (VTOL) capability. This concept also offers a simple lightweight cross-duct multiengine coupling which is adaptable to either a twin or four engine configuration. ...The selection of number of engines will depend on the safety of flight requirements in the VTOL mode. An inherent advantage of the split flow concept is the efficient propulsion control system which employs cross duct coupling between engines.

For example, Sikorsky is preparing a two-phase program beginning with the readily available 46-passenger S-65-40 helicopter, and followed by introduction of the 100-passenger S-200 compound aircraft in 1980. The VTOL market potential is discussed, as is projected acceptance of the VTOL short-haul system in the Northeast Corridor and the principal routes of western Europe. ...This paper traces the evolution of the VTOL short-haul concept from its origins in 1967 to the present. It shows how design proposals have become more responsive to the evolving system and economic requirements of the potential operating airlines.

Tern continues to undergo progress toward creating a new class of unmanned air systems combining shipboard takeoff and landing capabilities, enhanced speed and endurance, and supervised autonomy.

In the “What’s Next for Aerospace and Defense: A Vision for 2050” study, AIA, New York City-based McKinsey & Company, and other industry partners reveal a comprehensive 30-year, Industry 4.0 forecast of air travel and spaceflight based on improvements in automation and digitization, next-generation materials, alternative energy sources and storage, and increased data throughput.

A description is given of a medium-range transport with VTOL capabilities and its performance is compared with conventional aircraft.

The electric aircraft market continues to grow at a fast pace, boosted by increasing demand for ultralight electric test aircraft and innovative general aviation (GA) programs, such as urban air taxis for urban mobility. The global electric aircraft market, which includes hybrid-electric and all-electric aircraft and systems, will realize a compound annual growth rate of more than seven percent by 2022, predict market research analysts at Technavio in London.

A five year development program conducted by the propeller industry has resulted in several major design innovations: lightweight blades, integrated propeller and gearbox, variable camber, shrouded propellers, and redundant control systems, of which all are flight qualified and used in two major VTOL aircraft programs, XC-142 and X-22A. This paper reviews these developments, defines their performance, weight, and functional potentials, and describes their current hardware status.