Hello, My dad serves in 202nd Engineers Combat Bn he died in 1967 and I didn't get a chance to talk to him about his service time. I am trying to put together some facts about his service for his grandson. According to his discharge his (Military Occupational Specialty and No.was Height Finder Observer 692)My question is did the 202nd have artillery, and what other weaponry was available for their use? Thanks for any info Shirley.
You might have the wrong impression about what a Height Finder Observer actually did.
The military needs a lot of specialists. The Adult Vocational Technical Educational system, or Votech system at community colleges sprang from the system devised in the build up to WWII in the 1930 by the Armed Services. They needed thousands of trained mechanics, aircraft and automotive, electricians, radio repairmen, etc etc. In WWII the Japanese were producing about 700 pilots a year. We were producing 15,000 a year and had trained 250,000 by the end of the war.
The huge technological requirements meant that for every trigger puller actually in combat, there were 9 other GIs in support and technology related jobs even in the 1940's. That is why the army devised the Combat Infantryman's Badge. its pin about 3 inches long, with a garland wreath over a kentucky rifle musket on a baby blue back ground. It says I have met and fought the enemy. It is the most coveted of awards an army soldier can wear.
The Military Occupational Specialty 692 Height Finder Observer was someone with visual accuity capable of using a stereoscope for interpreting aerial photos for 3D stereoscopic viewing.
Its funny, I used to do that a lot and was an expert witness in environmental lawsuits. I would work up histories of sites using stereo photo pairs.
Now, Combat engineers did a lot of things, including making maps. Unlike today, they did not have satellites but relied in stead on aerial photos. If you take two photos from a plane in rapid succession such that they over lap by 60% a slight change in the shadowing between photos occurs as the plane changes position releative to the sun position.
This slight change in "parallax" results in two images nearly identical but with subtle variations. When viewed through a stereoscope, which is a device that forces each eye to look only at one of the two images using prisms and mirrors, it makes the human brain process the subtle variations in the two pictures resulting in a third imaginary image. This third image is a 3D image which shows height and depth. Kind of like the old view master viewers we used as a kid only different. Air photos would be taken by recon planes then provided to your father's unit. He might have been an officer, or Technical Sergeant.
There might be some confusion on the online sources as to what the job description really was. The one below seems to confuse range finder with Height Finder.
A range finder is a device used to aim artillery in the direct fire mode. It was an optical device with widely separated lenses. The operator looks into it and via a prism each eye's field of view is directed to the side and then forward separated by several feet. He sees two images and by adjusting the two images to one, can triangulate the distance to the target. ON battle ships, the range finders were tens of feet long, with one lense on each side of the massive gun turrets. The wider spaced the lenses the more accurate the range estimate since the base of the triange was wider. Using simple trigonometry, they could calculate the length of the other two sides of the isosolese triange ( a triangle with at least two sides of equal length).
Combat engineers did not aim artillery, artillery battalions had their own units for that. Combat engineers did prepare maps, and map terrain features. Using the photos and the steroscope, they could actually measure the height of objects like hills and such. This was critical for locating an naming hills in an area in which forces were to fight. It was also important to know the heigh of river shorelines if bridging equipment were to be needed.
The link below shows some of the old steroscopes. The small pocket steroscopes were not used fro measurements only the larger mirror and prism ones were along with a parallax bar used to take the measurements used to calculate elevation and heights from the photos.
Artillery units mainly did indirect fire, that is fired on targets not in line of sight, so an artillery range finder was of little use. Artillery units were surveyed into a location so that they knew where on a map they were, so they could use asimuth and range to fire at other locations on other map grids. GPS does that for them now.
692 - HEIGHT FINDER OBSERVER
[HT FINDER OBS]
Supervises a height finder team in setting up, adjusting, and operating a large stereoscopic range finder to determine distances to enemy aircraft or seacraft. (this was probably the description for the US Marines since they had coastal artillery batteries that used it for artillery.- KHP)
Must possess proper stereo-acuity and inter-pupillary measurements to perform as stereoreader of the team. Note—For team members not qualified as observers use SSN 596. (This sounds more like the role your father played - KHP)
Combat Engineers did find themselves in combat. The 202 Combat Engineer battalion was strumental in holding up the German advance at Stavelot, Belgium during the Battle of the Bulge long enough for forces to reach Bastogne to stymie the German Offensive.