Tag Archives: C-130 Hercules

Air, Unmanned Systems

Gremlin Air Vehicles

An unmanned air vehicle demonstrated successful airborne recovery during the Defense Advanced Research Projects Agency (DARPA) Gremlins program’s latest flight test deployment last month. During the deployment, two X-61 Gremlin Air Vehicles (GAV) successfully validated all autonomous formation flying positions and safety features before one GAV ultimately demonstrated airborne recovery to a C-130 Hercules.

X-61 Gremlin Air Vehicles (GAV)
Gremlins Air Vehicle during a test at Dugway Proving Ground, Utah, October 2021

«This recovery was the culmination of years of hard work and demonstrates the feasibility of safe, reliable airborne recovery», said Lieutenant Colonel Paul Calhoun, program manager for Gremlins in DARPA’s Tactical Technology Office. «Such a capability will likely prove to be critical for future distributed air operations».

During the final experiment, the team refurbished an X-61 vehicle and conducted a second flight within 24 working-hours. In addition, many hours of data were collected over four flights including air vehicle performance, aerodynamic interactions between the recovery bullet and GAV, and contact dynamics for airborne retrieval. Unfortunately, one GAV was destroyed during the flight tests.

«Airborne recovery is complex», said Calhoun. «We will take some time to enjoy the success of this deployment, then get back to work further analyzing the data and determining next steps for the Gremlins technology».

Safe, effective, and reliable air recoveries promise to dramatically expand the range and potential uses of unmanned air vehicles in conflict situations. The GAVs can be equipped with a variety of sensors and other mission-specific payloads. They can also be launched from various types of military aircraft, keeping manned platforms safely beyond the range of adversary defenses. After air retrieval, the GAVs can be refurbished by ground crews to prepare them for another mission within 24 hours.

Dynetics, a wholly owned subsidiary of Leidos, is developing the Gremlin vehicles.

DARPA Gremlins Program Demonstrates Airborne Recovery

Air, Unmanned Systems

First Flight

Defense Advanced Research Projects Agency’s (DARPA) Gremlins program has completed the first flight test of its X-61A vehicle. The test in late November at the U.S. Army’s Dugway Proving Ground in Utah included one captive-carry mission aboard a C-130A Hercules and an airborne launch and free flight lasting just over an hour-and-a-half.

Gremlins air vehicle during a flight test at Dugway Proving Ground, Utah, November 2019

The goal for this third phase of the Gremlins program is completion of a full-scale technology demonstration series featuring the air recovery of multiple, low-cost, reusable Unmanned Aerial Systems (UASs), or «Gremlins». Safety, reliability, and affordability are the key objectives for the system, which would launch groups of UASs from multiple types of military aircraft while out of range from adversary defenses. Once Gremlins complete their mission, the transport aircraft would retrieve them in the air and carry them home, where ground crews would prepare them for their next use within 24 hours.

The team met all objectives of the test in November, including gathering data on operation and performance, air and ground-based command and control systems, and flight termination. A parachute anomaly occurred in a recovery sequence that is specific to the test series and not part of the operational plan. The incident resulted in the loss of the test vehicle, one of five in the program. Four vehicles remain operational and available for the test series, which will continue in 2020.

«The vehicle performed well, giving us confidence we are on the right path and can expect success in our follow-on efforts», said Scott Wierzbanowski, the program manager for Gremlins in DARPA’s Tactical Technology Office. «We got a closer look at vehicle performance for launch, rate capture, engine start, and transition to free flight. We had simulated the performance on the ground, and have now fully tested them in the air. We also demonstrated a variety of vehicle maneuvers that helped validate our aerodynamic data».

The next step for the program is a full evaluation of the test data, as well as to understand any issues related to the failure for the main parachute to deploy. The team anticipates the second flight test at Dugway in the spring 2020 timeframe to remain on track.

The C-130 Hercules is the demonstration platform for the Gremlins program, but Wierzbanowski says the Services could easily modify the system for another transport aircraft or other major weapons system. Gremlins also can incorporate several types of sensors up to 150 pounds/68 kg, and easily integrate technologies to address different types of stakeholders and missions.

The U.S. Air Force designated the Gremlins air vehicle as X-61A in August in recognition of the technical challenges associated with the program.

A Dynetics-led team is the performer for the Phase 3 demonstration series.

Gremlins X-61A Maiden Test Flight