[alma-config]Re: Four antennas move every 2.5 days?

[Al Wootten]

Folks,

In the document approval request area of almaedm, there are several
documents relating to the ALMA configuration:

74. ALMA-90.02.00.00-002-A-SPE Long Baseline (Y+) Array
                 Configuration: Specifications and Requirements  Holdaway  
                  2003-11-04 11:02              (2)  

109. ALMA-90.02.00.00-003-A.SPE Array Reconfiguration Sequence
                 Conway
                  2003-11-14 03:00

68. ALMA-37.01.00.00-001-A-SPE System Requirements for the ALMA 
                 Antenna Transporter System
                M. Kraus / E. Pangole
                Date Decision Required: 2004-02-17 10:00

Neither of the first two have had any comment at all, presumably owing to
the brilliance of their conception.

John has provided comments on the last at my request.  Since the Operations
Group has devised a Plan, and since the transporter document makes
recommendations on specific move sequence timing, there have been some
discussions on this.  Please read the comments on document 68 at:
http://tinyurl.com/yrfop

One favored sequence John proposed:
==================John 2b mod of Mark 2====================================

STRAWMAN SEQUENCES

Modified Straw Man Reconfiguration Plan 2b:
sit in inner, from inner to outer, sit in outer, and back in;
Antenna move sequence M-X-X-M-X (M is a day when transporters
are used for antenna moves - give an average of 4
ant moves every  2.5 days)

compact array:  sit for 3 weeks             21 days

Marching out to Y11:  37 moves of 4 ants     93 days

Y11 array       sit for 3 weeks             21 days

Marching in:         39 moves of 4ants     105  days
to compact            plus 1 week
(include one week
stopped in 6-I)

Sub Total                                 240 days


Extra 15 days stopped, added               15 days
to compact, extended or
intermediate arrays ('Contingency')

Grand total                               255 days

                                    Exactly 9 months, so cycle
                                    repeats every 3 years, phase
                                    to avoid bad Tau in compact

I like this reconfiguration plan best, there is sufficent margin
for adapting the array. How the 15 extra days are used could be
varied.

===================================================================

We solicit comment.

Clear skies,
Al
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| Alwyn  Wootten   (http://www.cv.nrao.edu/~awootten/)	 |
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