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Journal Article

Vertical Takeoff and Landing Aircraft, Vertical Takeoff and Landing Ground Effects

2020-08-20
By strategically designing the vertical takeoff and landing (VTOL) ventral surface, reflection of the impinging fountain momentum is possible so that instead of losing 10% thrust while in ground-effect, remarkably, thrust is augmented 10% or more to a considerable height above the ground, in addition to stabilizing random pitch and roll moments caused by fountain instability.
Technical Paper

Vertical Attitude Takeoff and Landing Remotely Piloted Demonstration Vehicle

1975-02-01
751103
Launch and recovery of RPV's aboard ship has been identified by the Navy as a major design impact area. Vertical attitude take-off and landing offers attractive advantages to the Navy in that ship/RPV interface problems are alleviated. ...This vehicle during FY-1976 will be flight tested to assess vertical hover capability of the RPV in the turbulent aerodynamic wake generated by a ships superstructure while underway.
Technical Paper

NAVTOLAND (Navy Vertical Takeoff and Landing Capability Development) Project

1977-02-01
770990
A coordinated development of the aircraft flight control and display systems to provide flying qualities with satisfactory level of pilot workload and the shipboard and tactical site installed approach and landing guidance systems and visual landing aids to effect precision in touchdown will be applied toward improvement of the AV-8 Harrier and helicopter operations and development of total all-weather and rough sea operations of all future Navy and Marine Corps V/STOL aircraft and shipboard platforms and tactical sites.
Technical Paper

A Comparative Study of a Multi-Gas Generator Fan to a Turbofan Engine on a Vertical Takeoff and Landing Personal Air Vehicle

2006-08-30
2006-01-2435
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. ...Vehicle-level performance and sizing studies were implemented using the Grumman Design 698 tilt-nacelle V/STOL aircraft as a notional personal air vehicle (PAV), subjected to hypothetical single engine failure (SEF) emergency landing requirements and PAV mission requirements. An integrated analysis environment, which consists of design and simulation tools for SEF emergency landing; MGGF cycle analysis and sizing; and aircraft sizing and synthesis, was developed to perform studies on vehicle sizing, MGGF optimization, mission requirement tradeoffs, and sensitivity analyses of SEF emergency landing conditions. ...An integrated analysis environment, which consists of design and simulation tools for SEF emergency landing; MGGF cycle analysis and sizing; and aircraft sizing and synthesis, was developed to perform studies on vehicle sizing, MGGF optimization, mission requirement tradeoffs, and sensitivity analyses of SEF emergency landing conditions.
Technical Paper

ways of improving TAKE-OFF AND LANDING

1960-01-01
600026
These will improve the block speed characteristics of the aircraft and also give vertical take-off and landing capabilities. This paper discusses the advantages of each of these possibilities. ...These have an inherently higher take-off thrust to cruise thrust ratio than the jets, which vastly improves the take-off acceleration.
Technical Paper

The Effect of Propulsion System Parameters on Vertical Take-Off and Landing Performance of a Transport Aircraft

1964-01-01
640235
This paper discusses the variables of those system parameters that affect aircraft take-off and landing, and also provides data to aid in evaluating the compromise necessary for selecting an adequate and efficient propulsion system. ...The ability of V/STOL aircraft to take off and land vertically, while at the same time maintaining balance and control in the event of engine failure, requires selection of a propulsion system that satisfies all requirements of trim, control, and engine-out.
Technical Paper

Takeoff Predictions for Powered-Lift Aircraft

1986-10-01
861630
Takeoff predictions for powered lift short takeoff (STO) aircraft have been added to NASA AMES Research Center's aircraft synthesis (ACSYNT) code. ...The new computer code predicts the aircraft engine and nozzle settings required to achieve the minimum takeoff roll. As a test case, it predicted takeoff ground rolls and nozzle settings for the YAV-8B Harrier that were close to the actual values. ...Analysis of takeoff performance for an ejector-augmentor design and a vectoring-nozzle design indicated that ground roll can be decreased, for either configuration, by horizontally moving the rear thrust vector closer to the center of gravity, by increasing the vertical position of the ram drag-vector, or by moving the rear thrust vector farther below the center of gravity.
Technical Paper

Commercial Helicopter Outlook Vertical Take-off and Landing (VTOL) Aircraft Air Traffic Control System – An Analysis of Helicopter Air Traffic Control Problems

1966-02-01
660319
All that is needed is a relatively small landing and terminal area. By comparison, surface transportation whether by transit systems or private vehicles, assumes a rather inflexible pattern once it is established. ...Hard and controlled operating experience with a low frequency navigational aid and tests of various VTOL landing systems and techniques are reviewed. The use of the Air Traffic Control Beacon (secondary radar), communications and the relationship of VTOL requirements is compared to fixed wing requirements.
Book

Advances in Aircraft Landing Gear

2015-08-24
The aircraft landing gear system is relatively unique on board an aircraft—it is both structure and machine, supporting the aircraft on the ground, yet providing functions such as energy absorption during landing, retraction, steering, and braking. Advances in Aircraft Landing Gear is a collection of eleven hand-picked technical papers focusing on the significant advancements that have occurred in this field concerning numeric modeling, electric actuation, and composite materials. ...The content of Advances in Aircraft Landing Gear is divided into two sections: Analysis and Design Methods; and Electric Actuation, Control, and Taxi. ...For those looking for more information on aircraft landing gears, the SAE A-5 committee (the Aerospace Landing Gear Systems Committee), which meets twice a year, serves as a useful forum for discussion on landing gear issues and development.
Standard

Extraordinary and Special Purpose Landing Gear Systems

2012-10-03
CURRENT
AIR4846A
Section 2 of this document describes the features of landing gear which are addressed in the specific descriptions of various landing gears (Category A). ...A landing gear system comprises the most compelling assembly of engineering skills. Its importance to the successful design of an aircraft can be favorably compared with that of the aircraft's wings and engines. ...Its importance to the successful design of an aircraft can be favorably compared with that of the aircraft's wings and engines. A landing gear system consists of several different engineering disciplines, and is continually in the public eye especially with regard to safety.
Technical Paper

FAA STOL Approach, Landing, and Takeoff Operational Evaluation Tests

1968-02-01
680667
An operational evaluation of two aircraft which are candidates for metropolitan area STOL port operation has been made in the approach, landing, and takeoff regimes of flight. Information was obtained on characteristics such as instrument approach angle, beam width or softness, deviations from approach course, approach obstacle clearance planes, threshold crossing heights, landing distance, takeoff distance, offset approach angles, etc. ...Information was obtained on characteristics such as instrument approach angle, beam width or softness, deviations from approach course, approach obstacle clearance planes, threshold crossing heights, landing distance, takeoff distance, offset approach angles, etc.
Technical Paper

An Inexpensive Electronic Method for Measuring Takeoff and Landing Distances

1977-02-01
770477
The Gates Learjet airplanes are certificated under the F.A.R. 25 Transport Category airplane rules, the same as most other business jets, and all the Jumbos and Wide-Bodied jets. Take-off and landing field lengths must be measured in the certification process and had been measured at Learjet since its beginning with a portable phototheodolite owned by the FAA.
Technical Paper

Pilot Monitoring of Airplane Acceleration on Takeoff

1983-10-03
831415
But ironically, pilots have no direct, accurate means to assess actual airplane acceleration during takeoff. Despite a history of infrequent but sometimes catastrophic accidents in which takeoff performance was a factor, little progress has been made to remedy this situation. ...Timely detection of subnormal acceleration and appropriate pilot reaction either to continue the takeoff or to reject it and stop on the remaining runway is vital to the safe operation of today's transport category airplanes. ...A novel and promising approach which uses the onboard inertial navigation system also is described and is advocated as a means to enhance pilot judgment and decision-making during the takeoff roll. This scheme offers potential for significant improvement of air transport safety with a minimum of development effort and equipment cost.
Technical Paper

Critical Speed Testing of the Grumman X-29A Power Take-Off Shaft Subsystem

1984-10-01
841603
Critical speed tests were performed on the Power Take Off shaft subsystem of the Grumman X-29A advanced technology demonstration aircraft. Test speeds up to 20,000 rpm were run to insure stable operation up to the maximum installed overspeed of 17,250 rpm. The subsystem was instrumented with proximity probes and accelerometers to measure shaft displacement and vibration. This paper will show that unprocessed data from proximity probes and accelerometers does not reliably indicate the location of a critical speed, and it will outline a method for processing this type data to accurately determine the critical speed. An example of reverse precession, as well as the effects of unbalance on critical speed, will be presented.
Technical Paper

A Perspective on the First Century of Vertical Flight

1999-10-19
1999-01-5584
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. ...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.
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