Given the desire expressed elsewhere to "group planes which have similar names" you may find the following helps:

use warnings;
use strict;

my @aircraft = qw(AD3 DAL13 DAL14 DBR2 DBR4 DBR3 DEHA2 FG3 FG6);
my %byGroup;

push @{$byGroup{$_->[1]}}, $_->[0] for map {[/(([A-Z]+).*)/]} @aircraf
+t;
printf "Group %5s: %s\n", $_, "@{$byGroup{$_}}" for sort keys %byGroup
+;
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Prints:

Group    AD: AD3
Group   DAL: DAL13 DAL14
Group   DBR: DBR2 DBR4 DBR3
Group  DEHA: DEHA2
Group    FG: FG3 FG6
[download]