May 29, 2003

Robert Johnson

 

Actions from the May 28 meeting

 

1.            Updated list of milestones for the Tracker EM.  Note that we have started executing a new plan to get the drill fixture built, but it does delay the program by about a week, in addition to the 4-day delay already incurred in the titanium bracket delivery.  The following is a list of milestones.  The dates come from the current detailed MS Project schedule.

May 28, 2003

M55J closeouts in Italy

June 6, 2003

Titanium corner brackets and flexures and thermal straps delivered

June 9, 2003

Static test fixture parts delivered

June 17, 2003

Drill fixture delivered

June 17, 2003

Assembly of bottom trays begins

June 19, 2003

Pretest review for the static load test

June 26, 2003

K13-D Sidewall allowables obtained from coupon tests

July 3, 2003

Ship bottom trays to Los Alamos

July 10, 2003

Static test of first bottom tray completed

July 7, 2003

Pretest review for the vibration testing

July 14, 2003

Pretest review for the thermal-vacuum testing

July 15, 2003

Begin stacking trays into the tower

July 22, 2003

Begin vibration test of the tower

July 29, 2003

Begin thermal-vacuum test of the tower

August 21, 2003

Thermal-vacuum testing completed

2.            Backup sidewall panels in YS90

a)            We have 4 blank sidewalls in YS90 that were originally intended for the EM tower and that have not yet been drilled.  These might work for the existing EM tower design, but this requires a bit more investigation.

b)            If we use those blanks for the EM tower, we would not have any equivalent material for the static test fixture.  Since the purpose of the static test is to verify the flexure attachment to the bottom tray, maybe it is not essential to have the flight-material sidewalls for this.

3.            Strength test of the K13D material

a)            Plyform, in Italy, will make the coupons and test them for mechanical properties.  There is time to do this before the static test.  Tom Borden will work with the Italians to finalize the plan and schedule to get this done in time.

b)            Plyform cannot do thermal measurements on these coupons, so that will be done by a contractor in the U.S.

4.            Sidewall prepreg temperature

a)            The material sent to Italy was unfrozen for 7 days and since then has been at -20C in a freezer in customs.  It is rated for 30 days working time unfrozen and for 6 months frozen.  After 6 months it can be re-certified, as long as the integrated time unfrozen does not exceed 30 days.

b)            Plyform does the receiving/inspection of the material.  They are also able to do re-certification of prepreg that is more than 6 months old (not an issue in this case).

5.            Hytec & Lockheed analysis support of the Bari test plan.

a)            Hytec has done most of the analysis required for the vibration test, but I am communicating with them and the Bari group to ensure that this gets into a pre-test report and that all of the numbers needed to support the test are there.

b)            I am working to get needed information on the test configuration from Bari to Jeff Wang at SLAC so that the analysis can begin.

6.            Thermal requirements

a)            I will meet with Hartmut to make plans to write or update documentation on the Tracker end-of-life requirements, looking into the various margins to see if a worst-case localized temperature of 35C would be okay. 

b)            We will also consider whether there is any problem with 40C for a beginning-of-life test.

7.            Test plans

a)            Hytec is presently writing a test plan and pre-test analysis report for the static test.  This will be ready for review at least 10 days prior to the test.

b)            The Bari documents for the EM vibration and thermal-vacuum tests are being reviewed within the tracker but can also be looked at by others.  I am communicating with Bari about completing necessary procedure documents.

8.            Pre-test reviews

a)            Our schedule as presented at the meeting had a review for each test only a day or two prior to the test.  This was intended to be a final internal review to be sure all preparations are in place and will be retained.

b)            We have added to our schedule a pretest review of the plans and procedures 10 days prior to each test.

9.            Post-test results

a)            Within 1 week of completion of each test we will produce a brief preliminary report on the outcome.

b)            Within 1 month of completion of each test we will provide a complete presentation of the test results, including necessary analysis. 

c)            We will then write a formal report on the results for the archive.

d)            We have added these items to our schedule.