SPACE AGE RAILROAD

[Music] this is the Tularosa basin in south-central New Mexico centuries ago for tastes and his conquistadores move through this Basin on a quest for the king of Spain today the descendants of Mescalero Apache chief Geronimo live near the northeast corner of the Tularosa basin it is a story and historic land remote arid forbidding and quiet yet in the midst of all this apparent solitude there is a busy and productive organization devoted to making history in its own special way that organization is the high-speed track at Holloman Air Force Base this is the track a pair of welded frame rails spaced seven feet apart stretching nearly seven miles along the Basin floor the left or master rail is aligned to within plus or minus five thousandths of an inch of a reference line the right or east rail is aligned to the master rail to within plus or minus one one hundredth of an inch the direction of the track is almost due north it's hard to realize that almost eighteen years have passed since the first track run on the 23rd of June nineteen and fifty things have certainly changed the track then was only 3,500 feet long and by comparison with a sophisticated installation currently being used was somewhat primitive it's easy for me to look back with a certain amount of nostalgia and say ah those were the good old days in a sense they were but look at the progress that has been made since those so-called good old days during nineteen fifty four we were conducting a series of track tests on human responses to acceleration deceleration and wind blast which gained a certain amount of recognition the effects of that run were relatively negligible but the data obtained was invaluable the instrumentation consisted primarily of sensors mounted on my body and the sled plus cameras to record various stages of the run braking was provided by the momentum exchange technique still in use I might add let's take a look at how this system operates there are vertical slots cut at 11 foot intervals along the entire length of the track masonite dams are installed in the slots and the trough is filled with water a large steel scoop on the sled cuts through the masonite barriers picks up the water in the trough rotates it 180 degrees and pitches it forward reversing direction of one pound of water produces approximately 2 pounds of retarding force this is momentum exchange depending on the specific projects braking requirements the dam heights are computer determined the masonite is then cut and positioned in the trough to within 1/32 of an inch of the required height this technique is used to stop dual rail sleds the other principle system of braking involves the use of plastic water sausages for monorail tests these water filled bags are placed on the rail at a predetermined location and a braking force is applied as the sled impacts the bags in 1956 the Holliman test track was extended to 5,000 feet up to that time the 3,500 foot track had been used for six years and recorded some 230 separate test runs slightly over one year and 117 test runs later in August of 1957 the 35,000 foot came into being the scope and versatility of the present track lengthened 500 feet in 1966 to permit specialized glass testing really becomes quite difficult to describe at least within the confines of this film one of the unique features of this track is 6,000 feet of rain making equipment such testing makes up a major part of the tracks workload and is designed to study the effects of an artificial rain field on experimental and operational ray domes nose tones and materials the adjustable spray heads are spaced at 8 foot intervals and are able to generate a rain field of variable drop size and variable rain rate this rainmaking equipment is only an example of the wide range of services offered to any agency interested in testing on the track instrumentation of course is really the key this is Midway located at midpoint along the track house within this two-story block house is the mass of electronic equipment used to provide both customers and project people with a desired data on each test run conducted on the track for example sled profile measurement stations sled position versus time data is received here and recorded on magnetic tape and later computer converted to the velocity and acceleration information the method of obtaining such information is unique at 13 foot intervals along the track our light beam interrupters during the test run a sled borne sensing head with a light source and a photosensitive pickup crosses the interrupter the resultant break in the light beams produces a voltage pulse which is telemetered to Midway and recorded the telemetry receiving and recording equipment and timing equipment at Midway are some of the most sophisticated now in use in addition to the conventional frequency modulated FM FM system in use there is a capability for receiving and recording pulse code modulation PCM pulse duration modulated TDM and pulse amplitude modulated P AM telemetry on the roof of Midway is attract safety control centers during all countdowns and runs and until the all-clear is passed this sander is manned by a senior controller and his assistants to ensure that all safeguards are enforced the second part of the tremendous instrumentation set up here at the track involves the use of optical systems there are 73 of these camera stations located at 500 foot intervals along the track use of this system provides optical time distance data for each run in addition surveillance cameras are set up at the camera pads and tracking camera towers there are also sled Bourn camera stations and portable units for optical data recording of specific events as the sled traverses the track it is not uncommon for 50 or 60 cameras to be used on one test some of the cameras photographed the sled at a rate of 100 thousand frames per second this complex includes track headquarters instrumentation and engineering laboratories shops offices for contractors involved in current test programs and propulsion system storage and loading facilities both liquid and solid propellant Rockets are being used for sled testing there are advantages and disadvantages to both a number of things dictate the type of propulsion system economy is always a factor there are such variables as availability of specific propellants the ease or difficulty of storage sled size acceleration rate and thrust controllability all must be considered when carrying out planning and execution of any program in the area of the test vehicles themselves there are over a hundred available ranging from tiny high velocity mono rails to massive dual rail sleds the size shape weight and frontal area of the payload are extremely important in determining the type of sled for a given test computer runs are usually made to determine the best combination of propulsion system and test vehicle based on specific program requirements the track directorate does design and build special sleds if none are available in the inventory the one area we haven't covered concerns the block houses at the track there are four permanent block houses there is one at the north and one at the south end one halfway down the track and one 3,000 feet from the south end in addition there is a portable fire control trailer this arrangement permits total flexibility sleds can be fired at any location and in either direction each block house contains communications equipment sled firing circuits and telemetry pre firing check out equipment as many as 100 channels of sled data are controlled and monitored from the block house prior to firing enough of the physical layout here at the Holloman tract it is big and impressive installation staffed by skilled dedicated professionals all the planning coordination designing and computation come into sharp focus as a sled sits on the end of the track before being fired for the next few moments while we wait for the launch I want you to watch the drama of the track as it unfolds almost daily [Music] [Music] [Applause] [Music] [Music] [Music] [Music] [Music] [Applause] [Music] [Music] the track to date has conducted over 4,500 test runs on projects covering missile guidance systems aircraft ejection systems rain erosion studies impact studies and biomedical explorations on both man and monkeys this has made the Holloman track one of the foremost research and development facilities in the United States [Music] [Music] [Music] [Applause] [Music]