| Unit Name: | Heavy Attack Squadron 21 |
| Dates: | 1 September 1968-16 June 1969 |
| Country: | United States |
| Branch: | United States Navy |
| Role: | Attack |
| Command Structure: | Inactive |
| Nickname: | Roadrunners |
| Battles: | Vietnam War |
| Aircraft Attack: | AP-2H Neptune |
VAH-21, nicknamed the Roadrunners, was a short-lived Heavy Attack Squadron of the U.S. Navy, based at Naval Station Sangley Point, Philippines. The squadron flew the specialized AP-2H version of the Lockheed P-2 Neptune aircraft, of which four examples were converted from standard SP-2H airframes.[1]
The squadron was established on 1 September 1968, as the first squadron in the Navy with a night interdiction mission using new electronic surveillance equipment. Its mission was to interdict logistics moving over land or sea. A detachment of VAH-21 was immediately established at a Navy facility associated with Cam Ranh Air Base, South Vietnam. The detachment had been a Naval Air Test Center Project TRIM Detachment (TRIM: Trails Roads Interdiction Multi-sensor) prior to becoming a VAH-21 detachment. VAH-21 was disestablished on 16 June 1969.