The current master:tip revision (0e7d7ff63b58) produces 

...
begin_operator
takeoff airplane_cfbeg seg_rwe_0_50 south
1
15 1
16
0 0 5 0
0 1 -1 1
0 2 -1 1
0 3 -1 1
0 4 -1 1
0 5 -1 1
0 6 -1 1
0 7 -1 1
0 8 -1 1
0 9 -1 1
0 10 -1 1
0 11 -1 1
0 12 -1 1
0 13 -1 1
0 14 -1 1
0 24 -1 1
0
end_operator
...

The issue appears to be fixed as there are no redundant effects anymore.

translate.py in the svn versions 2819 and a the recent one (tested by malte)
produce redundant effects for the airport-adl domain.

Example: airport-adl:p01-airport1-p1.pddl

Translator output:

...
takeoff airplane_cfbeg seg_rwe_0_50 south
 PRE: var1 = at-segment(airplane_cfbeg, seg_rwe_0_50)
 PRE: var3 = facing(airplane_cfbeg, south)
 EFF:  -> var1 := airborne(airplane_cfbeg, seg_rwe_0_50)
 EFF: occupied(seg_rwe_0_50) -> var2 := <none of those>
 EFF: blocked(seg_rw_0_400, airplane_cfbeg) -> var4 := not-blocked(seg_rw_0_400,
airplane_cfbeg)
 EFF: blocked(seg_pp_0_60, airplane_cfbeg) -> var5 := not-blocked(seg_pp_0_60,
airplane_cfbeg)
 EFF: blocked(seg_rww_0_50, airplane_cfbeg) -> var7 := not-blocked(seg_rww_0_50,
airplane_cfbeg)
 EFF: blocked(seg_rwtw1_0_10, airplane_cfbeg) -> var8 :=
not-blocked(seg_rwtw1_0_10, airplane_cfbeg)
 EFF: blocked(seg_tww4_0_50, airplane_cfbeg) -> var9 :=
not-blocked(seg_tww4_0_50, airplane_cfbeg)
 EFF: blocked(seg_twe2_0_50, airplane_cfbeg) -> var10 :=
not-blocked(seg_twe2_0_50, airplane_cfbeg)
 EFF: blocked(seg_ppdoor_0_40, airplane_cfbeg) -> var11 :=
not-blocked(seg_ppdoor_0_40, airplane_cfbeg)
 EFF: blocked(seg_tww3_0_50, airplane_cfbeg) -> var12 :=
not-blocked(seg_tww3_0_50, airplane_cfbeg)
 EFF: blocked(seg_tww1_0_200, airplane_cfbeg) -> var14 :=
not-blocked(seg_tww1_0_200, airplane_cfbeg)
 EFF: blocked(seg_twe1_0_200, airplane_cfbeg) -> var15 :=
not-blocked(seg_twe1_0_200, airplane_cfbeg)
 EFF: blocked(seg_twe4_0_50, airplane_cfbeg) -> var16 :=
not-blocked(seg_twe4_0_50, airplane_cfbeg)
 EFF: blocked(seg_tww2_0_50, airplane_cfbeg) -> var17 :=
not-blocked(seg_tww2_0_50, airplane_cfbeg)
 EFF: blocked(seg_twe3_0_50, airplane_cfbeg) -> var19 :=
not-blocked(seg_twe3_0_50, airplane_cfbeg)
 EFF: blocked(seg_rwe_0_50, airplane_cfbeg) -> var20 :=
not-blocked(seg_rwe_0_50, airplane_cfbeg)
 EFF: blocked(seg_rwe_0_50, airplane_cfbeg) -> var20 :=
not-blocked(seg_rwe_0_50, airplane_cfbeg) 
...

The last effect is unneeded. It is produced because of the form of the operator
in the airport-adl domain.pddl file:

(:action takeoff
 :parameters   (?a - airplane ?s - segment ?d - direction)
 :precondition (and
                (at-segment ?a ?s)
                (facing ?a ?d)
                (is-start-runway ?s ?d)
     )
 :effect (and (not (blocked ?s ?a))
              (not (occupied ?s))
              (not (at-segment ?a ?s))
              (airborne ?a ?s)
              (forall (?s1 - segment)  (when (blocked ?s1 ?a)
                                             (not (blocked ?s1 ?a))
                                       )
              )
         )
)

One segment is unblocked by an unconditional effect AND a conditional quantified
effect.

The output is semantically correct, but the redundant effect should nonetheless
be omitted.