Author: E. L. ColePublisher:
ISBN:
Category : Aeronautical instruments
Languages : en
Pages : 24
Book Description
Brightness Levels of Three Instrument Lighting Systems Used by Pilots Flying at Night
Author: E. L. ColePublisher:
ISBN:
Category : Aeronautical instruments
Languages : en
Pages : 24
Book Description
Brightness Levels of Three Instrument Lighting Systems Used by Pilots Flying at Night
Author: Publisher:
ISBN:
Category :
Languages : en
Pages : 0
Book Description
Information obtained from twelve pilots flying a C-47 aircraft at night using three different instrument lighting systems is presented. These systems were: (1) Red Flood, (2) Indirect Red, and (3) Ultra-Violet. Brightness levels used by the pilots were recorded for the three systems under varying flying conditions. These conditions were (1) normal night flying, (2) night instrument (maximum), and (3) minimum brightness necessary for safe flight. For normal conditions the lowest brightness level used occurred under Red Flood and highest under Indirect Red. At minimum levels Indirect Red was lowest followed by Ultra-Violet and Red Flood. At maximum levels (night instrument condition) Red Flood was highest, Indirect Red next and Ultra-Violet the lowest although this position of Ultra-Violet represented the maximum available brightness range for this system. Pilot opinion showed varying preferences for the different conditions. Indirect Red was preferred as being the most pleasant and comfortable system and Red Flood was preferred as being the most effective of the three.
The Effects of Pure Red and Low-color-temperature White Instrument Lighting Upon Dark-adapted Visual Thresholds
Author: Kenneth T. BrownPublisher:
ISBN:
Category : Aeronautical instruments
Languages : en
Pages : 48
Book Description
"The effects of pure red and low color temperature white flood lighting upon completely dark adapted visual thresholds have been determined. The red light was adjusted to brightness levels which pilots have been found to use as the minimal, normal, and maximal levels for night flying. For each brightness level of the red light, a brightness was found for the low color temperature white light at which aircraft instruments were equally legible under the two lighting systems. Both a simulated instrument panel and a pure white panel were used as viewing panels. Six subjects were tested under each lighting condition. A higher brightness proved necessary with the low color temperature white light than with the pure red light in order to attain equal legibility of instruments. Both lighting systems at all brightness levels caused small increases in visual thresholds above the completely dark adapted state. When the simulated instrument panel was illuminated at the normal brightness level, thresholds after viewing low color temperature white light were 0.15 log micro-microlamberts above thresholds after viewing pure red light. This value defines the approximate sacrifice in dark adaptation which would be made if white lights, operated at low voltage, were substituted for red lights in flood lighting aircraft instruments. The white lighting would also be more visible to dark adapted enemy observers. However, the white lighting system would make colors in the cockpit appear more natural, which would facilitate such tasks as map reading. When operated at normal voltage, the white lighting system could also provide high intensity illumination for special purposes such as thunderstorm flying, very high altitude daytime flight, and simulated instrument flying with the amber hood and blue goggles."--Abstract.
The Effects of Pure Red and Low-color-temperature White Instrument Lighting Upon Dark-adapted Visual Thresholds
Author: Kenneth T. BrownPublisher:
ISBN:
Category : Aeronautical instruments
Languages : en
Pages : 0
Book Description
"The effects of pure red and low color temperature white flood lighting upon completely dark adapted visual thresholds have been determined. The red light was adjusted to brightness levels which pilots have been found to use as the minimal, normal, and maximal levels for night flying. For each brightness level of the red light, a brightness was found for the low color temperature white light at which aircraft instruments were equally legible under the two lighting systems. Both a simulated instrument panel and a pure white panel were used as viewing panels. Six subjects were tested under each lighting condition. A higher brightness proved necessary with the low color temperature white light than with the pure red light in order to attain equal legibility of instruments. Both lighting systems at all brightness levels caused small increases in visual thresholds above the completely dark adapted state. When the simulated instrument panel was illuminated at the normal brightness level, thresholds after viewing low color temperature white light were 0.15 log micro-microlamberts above thresholds after viewing pure red light. This value defines the approximate sacrifice in dark adaptation which would be made if white lights, operated at low voltage, were substituted for red lights in flood lighting aircraft instruments. The white lighting would also be more visible to dark adapted enemy observers. However, the white lighting system would make colors in the cockpit appear more natural, which would facilitate such tasks as map reading. When operated at normal voltage, the white lighting system could also provide high intensity illumination for special purposes such as thunderstorm flying, very high altitude daytime flight, and simulated instrument flying with the amber hood and blue goggles."--Abstract.
Technical Information Pilot
Author: Human Engineering Guide for Equipment Designers
Author: Publisher: Univ of California Press
ISBN:
Category :
Languages : en
Pages : 286
Book Description
Visual Recovery Times from High-intensity Flashes of Light
Author: Robert D. MetcalfPublisher:
ISBN:
Category : Brightness perception
Languages : en
Pages : 22
Book Description
"A high-intensity carbon arc was used as a light source to determine the course of visual recovery after exposure to a level of illumination comparable to that likely to be encountered during nuclear operations. The subjects in the experiment were exposed to a source subtending 3°58' at the eye and with a luminance of up to 15 x 106 foot-lamberts. Exposure time was constant at 0.1 second. Recovery time plotted against illumination at the eye (and source brightness) produced a straight line curve in a semilog plot. Extrapolation to the estimated burn threshold indicates a maximum recovery time of 170 seconds to discriminate a brightness contrast comparable to reading red-lighted aircraft instruments. Recovery times to other brightness levels are also indicated."--Abstract
The Effects of Two Instrument Lighting Systems on Dark Adaptation
Author: Lawrence R. WilcoxPublisher:
ISBN:
Category : Aeronautical instruments
Languages : en
Pages : 42
Book Description
Four pilots with normal vision were tested for the effects of the standard indirect red and red-flood aircraft lighting systems on dark adaptation. Data were gathered in a completely blacked-out cockpit while the aircraft was in a hanger and also during conditions of normal night flight. Significant differences in dark adaptation thresholds were found between the hangar and flight phases and between the low and high levels of light intensity used. No significant differences were found between the types of lighting systems used. It is concluded that the flight conditions of starlit night sky affect dark adaptation levels to a significant degree.
Visual Presentation of Information
Author: Charles A. BakerPublisher:
ISBN:
Category : Human engineering
Languages : en
Pages : 120
Book Description
"An important factor in the design of equipment for maximum efficiency of human operation is the design, illumination, and arrangement of visual displays which provide information to the human operator. This report provides a compilation of general human engineering recommendations and presents some of the supporting data which should aid the engineer in providing the most satisfactory visual presentations of information. The report is divided into seven chapters entitled: mechanical indicators, warning devices, cathode-ray tubes and signal coding, printed materials, instrument panel layout, lighting, and visual detection and identification. Liberal use is made of pictorial, graphic, and tabular presentations to illustrate the data and design recommendations. A table of contents, subject index, and a selected bibliography are included as an aid to the user."--Abstract.
Review of the Cone-to-rod Efficiency Ratio as a Specification for Lighting Systems
Author: John Lott BrownPublisher:
ISBN:
Category : Bars (Engineering)
Languages : en
Pages : 30
Book Description
"The need for systems of illumination which will afford the maximum stimulation of the eye at low luminances has led to the widespread use of red light. The theoretical basis for the advantage of red light is reviewed. Several methods for the practical specification of illumination which are based on a cone-to-rod luminous efficiency ratio are considered. These methods are analyzed and compared in terms of the actual physical significance of the numerical values which they yield. It is evident that no method of calculating a cone-to-rod ratio provides an index from which the effects on sensitivity after adaptation to a given illumination system can be predicted. The general problem of specification is discussed in relation to a number of the underlying practical problems, such as luminance level at which a given illumination system must be used, the nature of the visual tasks for which it is provided, and the nature of the visual tasks for which sensitivity must be preserved. It is concluded that a cone-to-rod luminous efficiency ratio may afford a satisfactory index for the specification of lighting systems. However, the use of such a ratio to predict the effect on eye sensitivity of exposure to different lighting systems must await a careful experimental investigation of the relations among cone-to-rod ratio, luminance, and criteria of sensitivity within the context of specific practical situations."--Abstract.