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Brown, J. H., Jr.

Publications and source records attributed to Brown, J. H., Jr..

Analytical study of a free-wing/free-trimmer concept

The free-wing/free-trimmer is a NASA-Conceived extension of the free-wing concept intended to permit the use of high-lift flaps. Wing pitching moments are balanced by a smaller, external surface attached by a boom or equivalent structure. The external trimmer is, itself, a miniature free wing, and pitch control of the wing-trimmer assembly is effected through a trailing-edge control tab on the trimmer surface. The longitudinal behavior of representative small free-wing/free-trimmer aircraft was analyzed. Aft-mounted trimmer surfaces are found to be superior to forward trimmers, although the permissible trimmer moment arm is limited, in both cases, by adverse dynamic effects. Aft-trimmer configurations provide excellent gust alleviation and meet fundamental stick-fixed stability criteria while exceeding the lift capabilities of pure free-wing configurations.

Porter, R. F.↗

Evaluation of the tilt rotor concept: The XV-15's role

The need for an aircraft combining the efficient vertical takeoff and landing capability of a helicopter with the efficient high speed characteristics of a fixed wing turboprop is examined. The ability of the tilt rotor concept to fill this requirement and examples as to its potential usefulness in both military and civil missions is discussed.

Brown, J. H., Jr.↗

XV-15 tilt rotor test - Progress report

In a continuing effort to expand the versatility of their aircraft, VTOL designers have for many years tried to combine the desirable features of various concepts into a single aircraft. This is a formidable task and most efforts have met with limited success. This paper explores the need for an aircraft combining the efficient VTOL capability of a helicopter with the efficient high speed characteristics of a fixed wing turboprop. The ability of the tilt rotor concept to fill this requirement and examples as to its potential usefulness in both military and civil missions is discussed. The history of the concept and the status of the current Army/NASA/Bell XV-15 program and its role in proving the viability of the concept are reviewed.

Brown, J. H., Jr.↗

Status report on XV-15 Tilt Rotor Test Program

The XV-15 Tilt Rotor Research Aircraft Program has progressed from the design and fabrication stage to the test phase and is now beginning that portion of the program which will culminate in the determination of the viability of this promising concept. This paper will review the joint Army/NASA/Bell Helicopter Textron (BHT) XV-15 program as it currently stands, including the results of the experience gained during the design and fabrication phases and testing to date. Highlights of the overall Tilt Rotor Program will be discussed exploring the potential of this concept to result in a new generation of highly productive VTOL systems.

Brown, J. H., Jr.↗