Stock Market Today, July 20: Archer Aviation Surges 20% on Thunder VTOL Platform Unveiling with Anduril

Archer Aviation surged 20% after unveiling Thunder, a hybrid-electric autonomous attack rotorcraft developed with defense company Anduril. The platform targets both commercial and defense markets, with first flight planned for 2027. Despite the rally, Archer remains down 55% over the past year, and analysts recommend cautious, incremental investing given the company's pre-profitability status and high volatility.