NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: astrocompass still in use
From: Paul Hirose
Date: 2002 Sep 26, 11:04 -0700
From: Paul Hirose
Date: 2002 Sep 26, 11:04 -0700
Robert Eno wrote: > > You worked on B-52's??? Now that is very interesting. Were you a pilot? > Navigator? I would give anything to get a ride on one of those babies! ... > I'd love to have a gander at the MD-1 Astrocompass. It sounds like a very > interesting device. I was in avionics maintenance in the USAF for many years, working on the B-52, B-1, and B-2. The MD-1 was part of the old ASQ-38 vacuum tube bomb-nav system on the B-52. This Web page lists the four main subsystems: http://www.csd.uwo.ca/~pettypi/elevon/baugher_us/b052-13.html I worked in the Bomb-Nav shop. Our world was the last subsystem on the list, the ASB-9A or ASB-16. The remaining ones belonged to other shops. I think Instrument/Autopilot shop took care of the first two, and Radar shop the last. It took a lot of different skills to keep the ASQ-38 working! My recollection (about 20 years old, and remember I didn't work on the astrocompass) was that the MD-1 had a clock-like dial where you set GHA Aries. I assume an internal clock on sidereal time kept it updated after that. There were two pairs of counters like odometers where you set the SHA and declination of two stars. The system could only track one at a time but you could change stars at the flick of a switch. There may have been an instrument to display azimuth or precise heading, and there definitely was one for intercept. There was no automatic way to shift the present position counters based on the intercept from the astrocompass. You would have to manually change them. That part I'm sure about, since it was what I worked on. Back in those days (early 80s) the B-52 carried a periscopic bubble sextant too. You'd commonly see the Air Almanac and HO 249 stuffed behind the nav's seat. I think the gunner normally operated the sextant, calling his readings down to the nav.