SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Schedule 13G Under the Securities Exchange Act of 1934 Amendment No. 3 Autoclave Engineers, Inc. ______________________________________________________________________________ (Name of Issuer) Common Stock ______________________________________________________________________________ (Title of Class of Securities) 052760105 ______________________________________________________________________________ (CUSIP Number) Check the following box if a fee is being paid with this statement CUSIP No. 1) Names of Reporting Persons S.S. or I.R.S. Identification Nos. of above persons PNC Bank Corp. 25-143-5979 2) Check the Appropriate Box if a Member of a Group (See Instructions) a) b) 3) SEC USE ONLY 4) Citizenship or Place of Organization Pennsylvania Number of Shares 5) Sole Voting Power 561,954 Beneficially Owned By Each Reporting Person With 6) Shared Voting Power 0 7) Sole Dispositive Power 114,609 8) Shared Dispositive Power 0 9) Aggregate Amount Beneficially Owned by Each Reporting Person 561,954 10) Check if the Aggregate Amount in Row (9) Excludes Certain Shares (See Instructions) 11) Percent of Class Represented by Amount in Row (9) 13.33 12) Type of Reporting Person (See Instructions) HC SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Schedule 13G Under the Securities Exchange Act of 1934 Amendment No. 3 Autoclave Engineers, Inc. ______________________________________________________________________________ (Name of Issuer) Common Stock ______________________________________________________________________________ (Title of Class of Securities) 052760105 ______________________________________________________________________________ (CUSIP Number) Check the following box if a fee is being paid with this statement CUSIP No. 1) Names of Reporting Persons S.S. or I.R.S. Identification Nos. of above persons PNC Bank, National Association 2) Check the Appropriate Box if a Member of a Group (See Instructions) a) b) 3) SEC USE ONLY 4) Citizenship or Place of Organization Pennsylvania Number of Shares 5) Sole Voting Power 561,954 Beneficially Owned By Each Reporting Person With 6) Shared Voting Power 0 7) Sole Dispositive Power 114,609 8) Shared Dispositive Power 0 9) Aggregate Amount Beneficially Owned by Each Reporting Person 561,954 10) Check if the Aggregate Amount in Row (9) Excludes Certain Shares (See Instructions) 11) Percent of Class Represented by Amount in Row (9) 13.33 12) Type of Reporting Person (See Instructions) BK Item 4 - Ownership: (a) Amount Beneficially Owned: 561,954 (b) Percent of Class: 13.33 (c) Number of shares to which such person has: (i) sole power to vote or to direct the vote 561,954 (ii) shared power to vote or to direct the vote 0 (iii) sole power to dispose or to direct the disposition of 114,609 (iv) shared power to dispose or to direct the disposition of 0 Item 10 - Certification. By signing below I certify that, to the best of my knowledge and belief, the securities referred to above were acquired in the ordinary course of business and were not acquired for the purpose of and do not have the effect of changing or influencing the control of the issuer of such securities and were not acquired in connection with or as a participant in any transaction having such purposes or effect. Signature. After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct. February 14, 1994 _____________________________________________________________________ Date _____________________________________________________________________ Signature /s/ Timothy N. Smyth, Senior Vice President and Trust Division Manager _____________________________________________________________________ Name/Title _____________________________________________________________________ Date _____________________________________________________________________ Signature _____________________________________________________________________ Name/Title Item 10 - Certification. By signing below I certify that, to the best of my knowledge and belief, the securities referred to above were acquired in the ordinary course of business and were not acquired for the purpose of and do not have the effect of changing or influencing the control of the issuer of such securities and were not acquired in connection with or as a participant in any transaction having such purposes or effect. Signature. After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct. February 14, 1994 _____________________________________________________________________ Date _____________________________________________________________________ Signature /s/ Michelle A. O'Donnell, Assistant Vice President and Assistant Regulatory Counsel _____________________________________________________________________ Name/Title _____________________________________________________________________ Date _____________________________________________________________________ Signature _____________________________________________________________________ Name/Title