Don't use the table names in the select list:

CREATE VIEW IMEXtrlrUtilUNIONasapSM_VW as

SELECT top 100 percent OrderNbr, City, Shipper, Weight

from IMEXtrlrUtilShipMat_VW

Union

select top 100 percent OrderNbr, City, Shipper, Weight

from IMEXtrlrUtilASAP_VW

ORDER BY OrderNbr, City, Shipper

For the record, even if not including and Order By clause, I advocate never using Select * in a view. If you change the underlying schema of a table, you will have to recompile any views using Select * before they work correctly.