Complex sentence: The A- 7E's were replaced by F/A- 18 Hornets, and the SH-3 Sea Kings were replaced with SH-60's while the E- 2Cs and the A- 6Es received major upgrades.
Split into simpler sentences: The A- 7E's were replaced by F/A- 18 Hornets and the SH-3 Sea Kings were replaced with SH-60's. The E- 2Cs and the A- 6Es received major upgrades.