The Boston A-20 was the first bomber to be fitted with a tricycle undercarriage.In June 1942,the first American A-20C's of the 15th Bomber Squadron arrived in England. They were also used in North Africa. The primary version of the A-20 family was the heavily armed G version. The A-20J was a modified G version whichhad a fully glazed frame-less nose instead of the six rigidly mounted nose-guns.They served with the RAF under the name Boston Mk.IV and could carry 906 kg bombs.