In April 1862, Union and Confederate commanders deployed observation balloons near Yorktown during the Peninsula Campaign. Professor Sobieski Constantine Thaddeus Lowe, born in 1832, gathered aerial reconnaissance intelligence about the Confederate defenses from the hydrogen balloon Intredid.

(Right) Inflation of the Intrepid by the Union Army Balloon Corps. The Balloon Corps operated a total of seven balloons, with the Intrepid being favored by Chief Aeronaut Lowe.
(Photograph: Mathew Brady)

Tactical reports were provided to the Union army during the siege of Yorktown following a number of ascensions. The balloons ascended to 1,000 feet on two consecutive days. The deployment of Union balloons forced the Confederates to conceal their soldiers. The Confederates blacked out their camps after dark, created dummy encampments and gun emplacements .