A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
B-52 navigator in New York Times
From: Paul Hirose
Date: 2015 Dec 14, 19:43 -0800
From: Paul Hirose
Date: 2015 Dec 14, 19:43 -0800
This New York Times article on the B-52 mentions old fashioned navigation with stopwatch, slide rule, and protractor when the computer complex temporarily goes down. Part of the navigator instrument panel is shown. http://www.nytimes.com/2015/12/06/us/b-52s-us-air-force-bombers.html?_r=0 You enter a B-52 through a belly hatch. Take one step forward and a vertical ladder to your right goes through a square hole in the ceiling to the upper deck where the EWO (Electronic Warfare Officer), tail gunner, and pilots sit. Before I retired from the USAF (my entire career was in bomber avionics maintenance), the gunner was deleted from the crew and the gun removed. However, the last time I looked the control panels were still there. In the lower deck forward of the ladder are seats for the radar navigator (senior navigator, on the left) and navigator. There's enough space between them for a man to stand. At the rear of the compartment are racks for electronics, a urinal, and toilet. Once upon a time the computer crash mentioned in the article would have been my job to troubleshoot after flight. Back then, the OAS (Offensive Avionics System) had three identical IBM AP-101 general purpose processors for nav and weapon delivery. An instructor told me these were also the main processors of the space shuttle. The panel on the left third of the photo controls the processors. In 30+ years it hasn't changed. The DTU (Data Transfer Unit, not shown) has four slots for removable tape cartridges. In this case, the top row of status lights shows two tapes are installed. Below that you see the status of the three processors, then knobs to load them. You select the DTU slot that contains the software, the processor to load, and which program (1 - 4) to load. The button in the lower left starts the load, and the PROC SYNC button puts all loaded processors on line. Digits in the RES PGM readout (overexposed and hard to read) show what software is resident in each processor. Unfortunately the article has much bias and misinformation and should be taken with a grain of salt, or maybe a whole salt shaker. For instance, the B-70 never "spewed highly toxic exhaust." The exotic high energy "zip fuel" project was abandoned years before the B-70's first flight due to insuperable problems with toxicity and deleterious effects on engine components. However, what the article says about the B-52 processor complex taking "several minutes" to reboot is probably accurate. I remember reloading two or three processors was irritatingly slow. You had to wait for the tape to rewind after each one. Do they still use tape cartridges? I don't know. The middle third of the photo is munitions stuff. Note the guards over the switches. You must flip the guard up to throw a switch. Furthermore, each guard can be secured with copper wire. It takes a hard pull on the guard to break the wire. (Speaking of switch guards, in the early 1980s a B-52 crew chief at Griffiss AFB in New York, proud of "his" airplane, did some detailing in the cockpit. Among other things, he installed new guards on the landing gear emergency switches at the pilot station. Unfortunately, the new guards held the switches to the retract position. On its next mission the bomber slid on its belly off the end of the runway when the gear retracted on the takeoff roll. Though nobody got hurt, the plane was severely damaged. A co-worker who was stationed there at the time told me, "They wanted to hang the guy but couldn't do a thing to him because nobody could find any official guidance on switch guard installation!") In the right third of the photo are old school instruments. The small gauge is the outside air temperature indicator. Part of the radar presentation panel is visible at the bottom right corner. STC = sensitivity time control. This produces a variable receiver gain (with respect to time) to help equalize the intensity of near and far terrain on the scope. The small triangular "BW" knob coaxial with the STC knob varies the antenna beamwidth. Just out of sight are the marker intensity (e.g., for the range rings on a PPI display) and video gain knobs. Between them is a button to toggle between logarithmic and linear receiver response. LOG is selected. The photo shows only a small part of a panel which spans the full width of the lower compartment in front of the navigation team. There's also a panel on each side and an overhead panel. They are all packed with stuff. It's impressive. Not all the available space is occupied, however. There are metal plates to cover the empty areas. In some planes I saw the plates removed and HO 249 and the Almanac stuffed into the openings! I've also seen those publications in the storage bin behind the nav seat. Each navigator has a table which slides out from the console. There's a reasonable amount of space to plot on a chart. In case of ejection, pyrotechnic actuators automatically retract the tables before the seats fire. In the B-1 there's only one navigator and the table is small. And if you need a table in the B-2 there's only the lid of the storage compartment between the seats. Before the B-52 tail gunner was deleted he usually operated the sextant and the navigator reduced the sights. I suppose manual celestial on bombers is history now. As far as I know the B-1 never had any such provision. My first encounter with the B-2 was at the plant in Palmdale. Standing in a partly completed cockpit, I noticed a circular port in the ceiling, on the center line. A sextant port for emergency nav, I thought. Wrong. The hole was for an air refueling lead-in light! The B-2 does have an AINS (astro inertial navigation system), and eventually I had a chance to track stars in daylight. But that's another story.