NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: H.O. 249 when introduced
From: Dave Weilacher
Date: 2002 Mar 9, 09:26 -0500
From: Dave Weilacher
Date: 2002 Mar 9, 09:26 -0500
I have come up with an adequate answer to my question. I own an HO 249 volume 1 with a publication year of 1972. The preface starts with the following words: "This series of sight reduction tables, comprising three volumes"... The reason for my question was a friend who was a navigator in the US Navy in the seventies. He believes that HO 249 volume I is the only volume that was published then. That was because they were issued volume 1 but used HO 229 for all other reduction work. I proposed that the navy may have liked the benefit of volume 1, but would gain no real advantage by switching to volumes II & III. Atfer all, HO 229 was bought and paid for, says "Marine" in the title, and allows the officers to believe they can achieve 10 times the accuracy ov HO 249 volumes 2 - 3. An interesting side note here. My 1972 edition of volume 1 refers to the Marine tables to say that HO 249 vol 2 & 3 are similar. My 1978 edition of volume 1 makes no mention of HO 229 at all. > [Original Message] > From: Ken Gebhart> To: > Date: 3/8/2002 11:52:25 PM > Subject: Re: [NAV-L] H.O. 249 when introduced > > In answer to the question of when HO-249 tables were first published, I > have dug up the following bibliography: > > Aircraft Navigation Manual (HO-216) - 1941- says that HO-208, HO-211, and > HO-214 are the only tables used for sight reduction. > > Air Navigation - P.V.H. Weems- 1943- says that HO-214 and (pushing their own > product, Weems Line of Position Book), are the main methods used for air > navigation. They mention that the RAF Air Navigation Tables (A.N.T.) are > published in the US as HO-218, with no further explanation. > > Air Navigation- Army Air Force - 1944- says HO-218 is the primary means of > air sight reduction. It says HO-218 has HC values listed with respect to LHA > Star and DR Lat. for 22 "selected stars". These exist in the first half of > each volume, with the last half being like HO-214. Each volume covered 5 deg > of Lat. > > Duttons- Tenth Edition -1951- mentions that HO-218 and HO-249 are similar to > HO-214 in many ways. So, this is the first mention I could find for HO-249. > It looks like in the 7 years between 1944 and 1951 someone took the selected > stars from 218 and incorporated them into one volume 1 of HO-249. > > Maybe someone else has additional references that can pinpoint the first > HO-249. > > Ken Gebhart > > > Cliff Sojourner wrote: > > > From: "daveweilacher@earthlink.net" > > > Does anyone know when H.O. 249 tables were introduced? > > > > Hi Dave, > > > > all I could find quickly is, according to Bowditch (page 8, section 111) > > > > > In 1936 the first volume of Pub. No. 214 was made available; later, Pub. > > No. 249 was provided for air navigators. > > > Pub. No. 229, Sight Reduction Tables for Marine Navigation, has replaced > > Pub. No. 214. > > > > I would guess all three HO 249 volumes were published at the same time. > > > > -- > > these are the good old days > > Cliff Sojourner cls@employees.org --- David Weilacher --- daveweilacher@earthlink.net --- EarthLink: The #1 provider of the Real Internet.