Lewis gun
The mounting also permitted the Lewis gun to be fired obliquely forwards and upwards, to attack an enemy aircraft from behind and below: a favourite tactic of several "ace" pilots, including Albert Ball. The "Schräge Musik" fitting used by German night fighter pilots in the Second World War used the same basic principle. When fired forwards, the trigger of the Lewis gun was controlled by a Bowden cable (see illustration at the top of the article); when fired upwards, the pistol grip was held to steady the weapon and it was fired with the trigger (as illustrated here).