my ($one, $two, $three) = qw(1 2 3); # works just fine

##</code><code>##

#!/usr/bin/perl -w
use strict;

my $buffer;  # Defined elsewhere
my %hash;

my @keys = qw(flags x y mode3 callsign route spare1 spare2 flight_level);

@hash{@keys} = unpack ( "B16 n2 A4 A8 A2 A A A3 C2" }, $buffer);

print $hash{mode3};