SORTING QUERY OUTPUT

I have created a query form. I want to sort the output by a specific  field, in this case the status date. I believe i would use AnswerSortOrder in my coding to acomplish this but I am not certain. I looked in my Object Pal reference guide for a sample of this coding and tried to adapt it but am unable to get the query to sort: The coding is as follows:

method pushButton(var eventInfo Event)
 var
  sUNIT   String
  qryFLEET  Query
  tvAnswer  TableView
  FLEETFIELDS Array[STATUS DATE] STRING

 endVar
    qryFLEET.getAnswerSortOrder(FLEETFIELDS)

 sUNIT = Enter_UNIT.value

 qryFLEET = Query
 
   ANSWER: :PRIV:answer.db

   FLEET.UTILIZATION.db | MODEL  | UNIT       | SERIAL NUMBER  | STATUS |LOCATION/CUSTOMER | STATUS DATE |   LTD HOURS |
          | Check  | ..~sUNIT.. | Check     | CHECK  | CHECK     |  CHECK   |   CHECK  |

 
          
 EndQuery
 setAnswerSortOrder(FLEETFIELDS)
 executeQBE(qryFLEET)
 tvAnswer.open(":priv:answer.db")
 
endmethod

The error message is: Constant expected

any help would be appreciated.