210 COLLAPSE OF TEXAS TOWER NO. 4 



(The document referred to follows:) 



June 16, 1959. 

 Mr. John F. Donegan, 



CRLD, Air Force Cambridge Research Center, 

 L. G. HnnsLom Field, Bedford, Mass. 



Dear John : By this time you will have received our Report 173, describing 

 the motions and stresses of the TT-4 platform, as observed through the winter 

 of 1958-59. 



I believe an engineering study should be made evaluating quantitatively the 

 several methods proposed for reducing tower motions. 



Because of our experience in measuring the tower's excursions, and identify- 

 ing the origins of these excursions, I believe we are in a good position to carry 

 out further aTialyses. 



I would like to suggest for your consideration that a task be organized to make 

 an engineering study of the various methods of TT-4 reinforcement, together 

 with a prediction of the excursion reduction due to this reinforcement. 



I also recommend that we reiustrument the platform again this coming winter 

 to determine whether or not the underwater reinforcements now being carried 

 out by the Navy have been effective in reducing tower excursions. 

 Yours very truly. 



Given A. Bkewer, Chief Engineer. 



Senator Stennis. Mr. French, do you have anything further? 



Mr. French. I have no further questions, Mr. Chairman. 



Senator Stennis. Senator Saltonstall? 



Senator Saltonstall. No questions. 



Senator Stennis. Senator Symington ? 



Senator Symington. No questions. 



Senator Stennis. We appreciate your coming here, Mr. Brewer, 

 and I believe your testimony has been very relevant and very reveal- 

 ing in many ways. As I understand it, your examination and study, 

 aided by the recordings of your instruments showed that the bracing 

 of the structure under the water was totally ineffective. 



Mr. Bre^ver. That is correct. 



Senator Stennis. Yes. And you were never called back any more 

 after your first examinations and your first recordings 



Mr."^ Brewer. Well 



Senator Stennis (continuing). For similar work, I mean. 



Mr. Brewer. That is right. After they made the reinforcements 

 and put in the X-bi-acing and these things, we were never called 

 back again ; that is correct. 



Senator Stennis. All right. 



We thank you very much, and you, too, Mr. Vanstone. You are 

 here under subpena, and we appreciate very much your coming here, 

 sir. 



Is there anything further ? 



Mr. Brewer. Sir, there is one thing Mr. Vanstone pointed out which 

 should be in the record, and that is what we said about it being totally 

 ineffective under the water applies to the excursions we made which 

 were plus or minus 3 inches. 



Now, no one can say if it moved 4 inches they might have been in- 

 effective. If it were due to pin looseness, you can imagine if it went 

 4 inches, maybe the pins would take up. 



greatest motion detected was plus or minus 3 inches 



At least within the range we measured that winter, the bracing 

 within the sea was totally ineffective, but this must be qualified by 



