NATIONAL BUREAU OF STANDARDS REPORT

NBS PROJECT NBS REPORT

0201-20-2304 July 1, 1954 3478

Development, Testing, and Evaluation of

Visual Landing Aids

Consolidated Progress Report

to tlie

Airborne Equipment Division

Bureau of Aeronautics

Department of the Navy

For the Period

April 1 to June 30, 1954

for

Bureau of Aeronautics Projects

TED Iio. HBS-AE-10001

TED No. NBS-AE-10003

TED No. NBS-AE-10004

TED No. NBS-AE-10005

U. S. DEPARTMENT Of COMMERCE

NATIONAL BUREAU OF STANDARDS

Tta publication, rei Approved for public release by the

unless permission a Director of the National Institute of

25 ,d.c. Suchper Standards and Technology (NIST)

cal ly prepared If tl on October 9, 2015

in part, is prohibited

andards, Washington

port has been specifisport for its own use,
, v .
Development, Testing, and Evaluation of Visual Landing Aids

Quarter Ending June 30, 1954

Laboratory Tests

Test No. Requested

Study of the life characteristics of 36 seadromelight batteries.

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

Letter dated 3-16-54

Status* Mathematical analysis completed, two life tests completed,

third life test planned, informal report provided for BuAer

guidance, written report in preparation.

Electrical characteristics of four firmerites.

By telephone 3-9-54

Report submitted 4-8-54. Amperites were found to be an

improvement an previous designs.

21A-4/54

Status*

21A-5/54

Photometric and colorimetric elmracteristics

of two approach-angle lights.

In conference 3-31-54

Status* Test completed, report in preparation.

£sasMa&sa-Ac

The text of the first Part of the proposed U. S. Standard for signallight colors has been revised and discussed with representatives of the

Coming end ICopp Glass Companies. The text appears satisfactory for

general circulation but the diagrams proved too difficult to interpret.

A set of eight new diagrams is about 80% completed.

Mr. Breckenridge has attended two meetings of the Lighting and

Marking Panel as an advisor, a meeting of the Aviation Limiting Committee

held in conjunction with one of the Lighting and Marking Panel meetings.
* . * . > ' * £ 7 ,

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a meeting of the executive subcommittee of the Aviation Lighting Committee,

and one session of a meeting of the Armed Forces, N.R.C., Vision Committee.

Study of heliport lifting

A new model of an approach-angle light has been designed by Mr. R. W.

Crouch. Tiiis indicator requires approximately one-half the power re- quired for the units submitted by the Bureau of Aeronautics for test.

(21A-5/54 above). It is also lighter, smaller and provides color

indications with smaller angles of uncertainty than the units submitted. A model of this design has been furnished the Marine Corps

for flight tests in accordance with arrangements made in conference

with Bureau of Aeronautics representatives.

Kinorama research

At the close of the last quarter two problems which had come out of

the attempt to validate the kinorama were delaying the validation. They

were problems which had not been serious for the work done with the old

laboratory kinorama nor for the demonstrations which had been made with

the prototype model. A higher standard of performance, however, appeared

imperative if the lcinoroma is to be used for work on controversial problems.

These problems were the synchronizing of the recorder mechanism with the

tape of the kinorama and the elimination of unintended cues.

Of these problems, the second is the more important. Experiments

have been made in an effort to conceal tie unwanted cues by a veiling

illumination and a fluorescent filter has given promise of being satisfactory for this purpose. Further tests confirmed this conclusion but

showed it would be necessary to increase the contrast between the lights

and the background. An effort was made to do tills by using a different

ultraviolet filter between the irradiator end the tape but no improvement

resulted. As another means of obtaining increased contrast, efforts were

made to find a satisfactory dark material for the tape. A dark rubber

material proved to be an improvement from the visual standpoint but a tape made of it could not be made to track properly. Efforts were then

made to dye the tracing cloth which had been used as the tape and this

was finally accomplished by using an alcohol soluble dye combined with

a quick drying technique. Tapes made by this process appeared satisfactory until the w

TeatIier became humid when wrinkles appeared in them.

Comparison of these tapes with undyed tapes showed that the undyed tapes

had been similarly affected. An attempt was made to overcome the

wrinkling by installing a dehumidifier. By this means the humidity within

the kinorama itself could be reduced substantially but no method of

changing tapes or servicing the equipment without admitting damp air to

tire kinoraroa appeared feasible. If a trailer were available for housing

tire equipment, it is probable that the entire interior could be satisfactorily airconditioned. Since no trailer Iras as yet been obtained, the
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effort to obtain a belt that will remain flat in a humid atmosphere was

renewed. Experiments with a nylon belt were unsatisfactory , and we are

now working again with the rubber belt. It is believed that the tracking

problem can be solved by providing a more positive means of towing the

belt.

During the previous quarter a new circuit was devised for synchronizing the recorder and tape optically and the construction of two new

phototube chassis for this purpose ms started. These have been completed

and installed.

Other progress with the kinorama includes the replacement of the

temporary wiring in the telescope assembly with permanent wiring and the

development of a special grid on transparent plastic for analyzing records

of kinorama runs. This grid was found quite useful in checking experimental runs.

Seadrome lights

Progress lias been made with the development of seadrome lights through

the completion of the tests on the amperites (21A-4/54 above) and two life

tests on seadrome light batteries (21A-3/54). These latter have not yet

been reported as a third life test is to be included in this test.

Airfield lighting control panel

A contract was awarded to the Federal Electric Co. during the fiscal

year 1953 to build an experimental airfield lighting control panel. For

a long period the company showed no progress on its contract, but several

months ago, in response to pressure, production was started. Hie company

then experienced difficulty in devising a layout which would come within

the specified limits of size. A satisfactory layout was devised at this

Bureau and it is understood that the control panel has now been completed

except for the labeling of the switches. As soon as we have been informed

that the labelling has been finished, arrangements will be made for the

inspection of this panel at the company's plant.
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