diff -rupN Xfoil/src/xpol.f Xfoil-new/src/xpol.f
--- Xfoil/src/xpol.f	2010-11-08 23:26:54.000000000 +0100
+++ Xfoil-new/src/xpol.f	2015-09-05 19:32:59.982081390 +0200
@@ -516,6 +516,7 @@ C
 C
 C---- the polar dump file doesn't exist, so write new header
    60 CONTINUE
+      BACKSPACE(LU)
       WRITE(LU) NAME, 'XFOIL   ', VERSION
       WRITE(LU) MINF1, REINF1/1.0E6, ACRIT(1), ACRIT(2)
       WRITE(LU) MATYP, RETYP
@@ -948,7 +949,8 @@ C
  1000 FORMAT(A)
       GO TO 10
 C
- 90   RETURN
+ 90   BACKSPACE(LU)
+      RETURN
       END
 
 
@@ -958,7 +960,8 @@ C
  10   READ(LU,END=90,ERR=90) DUMMY
       GO TO 10
 C
- 90   RETURN
+ 90   BACKSPACE(LU)
+      RETURN
       END