NATIONAL BUREAU OF STANDARDS REPORT

NBS PROJECT

0201-20-2304

NBS REPORT

3222

Development, Testing, and Evaluation of

Visual Landing Aids

Consolidated Progress Report

to the

Airborne Equipment Division

Bureau of Aeronautics

Department of the Navy

for the period

January 1 to March 31, 1954

for

Bureau of Aeronautics Projects

TED No. NBS-AE-10001

TED No. NBS-AE-10003

TED No. NBS-AE-10004

TED No. NBS-AE-10005

<NBS>

U. S. DEPARTMENT OF COMMERCE

NATIONAL BUREAU OF STANDARDS

The publication, r Approved for public release by the

unless permisaion Director of the National Institute of

25 ,d.c, Such p< Standards and Technology (NIST)

cal ly prepared If 0 n October 9, 2015

r In part, Is prohibited

itandards, Washington

eport has been speclfireport for Its own use,
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DEVELOPMENT, TESTING, AND EVALUATION OF VISUAL LANDING AIDS

Quarter Ending March 31, 1954

Laboratory Tests

Test Noo Requested

Study of the life characteristics of 36 seadromelight batteries.

21A-3/54 In conference 2-12-54

Letter dated 3-16-54

Status: Samples awaited; advanced mathematical analysis completed.

21A-4/54

Electrical characteristics of four amperites.

By telephone 3-9-54

Status: Measurements completed; report in preparation.

Photometric and colorimetric characteristics

of two approach-angle lights.

21A-5/54 In conference 3-31-54

Status: Awaiting measurement.

Consultation Activities

Tentative boundaries have been adopted for all colors to be

included in the Standard for Signal-Light Colors. The work of preparing diagrams to illustrate these boundaries is approximately 50$

completed.

Mr. Breckenridge has attended meetings of the Lighting and

Marking Panel in Dayton, Ohio and Washington, D. C. Assistance was

furnished in reporting the status of projects being conducted by the

Airborne Equipment Division.

Study of Heliport Lighting

Several models illustrating the principle of beacon identification by compound rotation, which was proposed by Mr. A. L. Lewis of

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the Airborne Equipment Division, have been made and two demonstrations

of these models have been given to members of the Division. These

demonstrations indicated that beacons based on this principle- can be

so designed as to be more distinctive at ranges up to a mile than any

beacons now in use. For ranges in excess of a mile, longer ranges for

detection and recognition can probably be obtained with beacons of the

multiple-flash type such as have been tested by the Bureau of Aeronautics

at Patuxent and Areata. An improved code for this type of beacon, which

was devised by a member of our staff several years ago, is available if

at any time there appears to be a need for it. The present indications

seem to be that there is no immediately urgent need for powerful beacons

for the helicopters used by the Navy. The use of other types of lighting

for heliports has been discussed with representatives of the Airborne

Equipment Division in two conferences.

Kinorama Research

To explore the problem of analyzing the records of tests made with

the kinorama, a series of approaches was flown by one observer, and the

records were processed. The experience indicated that the time required

for reducing the data could be shortened if the ratio of forward speed

to recorder chart speed could be held more nearly constant. The drift

in this ratio produces a maximum difference of approximately 2.5% between

the chart lengths corresponding to 5000 feet of approach.

In an effort to stabilize the ratio of forward speed to recorder

chart speed, a feedback circuit was designed and installed with available equipment. Tests with this circuit showed no noticeable improvement in operation, but further tests with other stabilizing circuits

are planned and will be carried out when the more urgent task of validation of the kinorama permits.

It also became apparent from the test described above that the

relocation of the altitude pen to bring its records abreast of the

traverse records would also facilitate the reduction of data. A pen

specially modified for this purpose has been ordered from the manufacturer.

An occasional erratic performance of the time-indicating photocell

circuit during the program led to the further development of the projector-receiver units. The use of a projector of higher intensity led

to the design of a unit which promises to be more stable and to give a longer lamp life. The mechanical design of the units has been substantially improved, and the construction of the two new units is now about

80$ accomplished.

The work initiated last quarter with incandescent projectors for

equalizing the illumination on all of the visible surfaces was con- tinued, and an improved background lighting system was arranged. A

group of forty approaches, constituting the first exploratory test of

this aspect of the kinorama was flown, and the results showed that

this method of reducing the extraneous visual cues was unsatisfactory
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Experiments were then conducted with a reflecting filter in an

effort to obscure the differences in illumination which had not been

eliminated. A group of twenty approaches flown using such a filter

yielded results which suggest that this method largely obscures the

extraneous cues present, but reduces somewhat the visibility of the

simulated lights. However, mechanical difficulties encountered in

mounting this filter to accommodate all conditions which may arise

during a test have led to experiments with a different system.

Experiments with fluorescent filters are now in progress, and

a preliminary test of such a device suggests that it probably will

be as effective as a reflecting filter in obscuring differences in

background illumination. It appears to be superior to the reflecting

filter in two respects: tire installation and adjustment are con- siderably simplified, and the attenuation of the lights under inspection is somewhat reduced. However, the chromaticity of the fluorescent

filter appears to be somewhat questionable.

If further tests show that this method of eliminating extraneous

visual cues is satisfactory, the validation program can be started

at once.

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KINORAMA CONFERENCES & DEMONSTRATIONS*

Date

1-22-54

1-26-54

3-5-54

3-9-54

3-26-54

3-26-54

H.J.C. Pearson C.A.A. Evaluation Center,

Indianapolis, Ind.

Demonstration

Prof. Fox George Washington University

Demonstration & Conference on psychological design

of evaluation program

Ward D. Davis Lear, Inc., Washington, D.C.

Demonstration & Conference on simulator for

Air Force

Col. A. J. Pema Chief, Special Training Devices Div.

Maj . W.H.Wilhelmi Flight Simulator Section

Maj . L. Davenport Training Films Section

(Representing Director of Personnel Procurement and

Training, H.Q., U.S.A.F.)

A. L. Lewis Bureau of Aeronautics

The Kinorama as a Training Device

Maj. W.H.Wilhelmi" U.S.A.F.

Maj. Howard Ellsburg U.S.A.F.

Mr. Ray Stout U.S.A.F. Wright Field

The Kinorama as a Training Device

Ward D. Davis Lear, Inc., Washington, D. C.

Dr. C. J. Breitwieser Lear, Inc., Los Angeles

"Kinorama, from standpoint of building an experimental

model to be shown Aif Force."

* All demonstrations of the kinorama are cleared with the Airborne

Equipment Division in advance by telephone.