Complex sentence: Due to a shortage of SPAD S.XIIIs, the first fighter squadrons of the United States Army Air Service, used the Nieuport 28 on operations for a short time-giving the type the distinction of being the first fighter used on operations by a U.S. Squadron.
Split into simpler sentences: Due to a shortage of SPAD S.XIIIs, the first fighter squadrons of the United States Army Air Service (USAAS), used the Nieuport 28 on operations. During its short time in operational service with the USAAS, the Neiuport 28 became the first fighter used on operations by a U.S. Squadron.