The U.S. Air Force awarded Northrop Grumman [NOC] a potentially $3.6 billion operations and sustainment contract for the company’s  Battlefield Airborne Communications Node (BACN) on Jan. 21.

“This contract provides for research, development, test, and evaluation, integration and operations and sustainment for existing and future payloads contained in or connected to the BACN system and associated ground stations or controls, ancillary equipment, support equipment and system integration laboratories.,” DoD said in a contract announcement. Work is to be completed in San Diego and overseas locations by Jan. 24, 2026.

Last month, Northrop Grumman said that BACN has 200,000 combat hours in more than 15,500 missions since its first deployment with the U.S. Air Force in October 2008.

Carried on four Northrop Grumman EQ-4B Global Hawk Block 20 drones and three E-11A modified Bombardier business jets, BACN is a high-altitude, airborne communications gateway that translates and distributes multi-domain imagery, voice and tactical data for missions, such as airdrop, convoy, humanitarian assistance, close air support, and theater air control systems operations. The Air Force has dubbed BACN “Wi-Fi in the Sky.”

Northrop Grumman said that it accelerated BACN development and delivered the first system to the Air Force “in only nine months” in 2008 in response to a joint urgent operational need. “Improvements to the BACN system include enhancing data rates by 10 times, integrating new automation software to streamline communications and improve situational awareness, and implementing new military standard communications protocols,” the company said.

“Northrop Grumman is investing in developing low size, weight and power gateway systems which are designed to enable communications and cross domain translations between multiple beyond line-of-sight and line-of-sight networks and datalinks—inclusive of 5th to 4th, generation capabilities. The development of these systems includes a focus on multi-level secure and integrated functions such as cloud computing, machine learning, artificial intelligence, next generation data links and the use of third-party software and sensor solutions.” BACN has had a mission availability rate of more than 98 percent, Northrop Grumman said.

On Jan. 21, Air Combat Command released an accident investigation report on a BACN E-11A that crashed in Afghanistan last Jan. 27 and killed the two pilots. The aircraft was on a combat sortie to support Operation Freedom’s Sentinel when “a fan blade broke free from the left engine, causing the left engine to shut down,” ACC said. “Approximately 24 seconds after the initial incident, the crew shut down the right, and only operable, engine resulting in a dual engine out emergency.”

According to the Accident Investigation Board (AIB) report, “the crew alerting system did not directly indicate the left engine failure,” a failure which caused the aircraft to shake violently.

The AIB “determined the cause of the mishap was the crew’s error in analyzing which engine had catastrophically failed,” per ACC. “This error resulted in the decision to shut down the working engine, creating a dual engine out emergency. Additionally, the AIB president found that the crew’s failure to airstart the right engine and their decision to recover the aircraft to Kandahar Airfield, Afghanistan, substantially contributed to the mishap.”

“Due to aircraft vibrations and the dual engine out emergency, both the cockpit voice recorder [CVR] and the digital flight data recorder stopped recording for the majority of the mishap sequence, which denied the direct evidence of certain events,” ACC said. “Therefore, the exact experience of the crew cannot be fully determined.”

In an email, ACC said that the E-11A program “has not discussed with Bombardier any equipment modifications” and that the command “is addressing the situation through incorporating training specific to the malfunction experienced by the aircrew in this mishap into initial and refresher E-11A training.”

Because of the stoppage of the CVR before the accident last Jan. 27, AIB investigators could not determine the crew’s experience and so looked to a similar engine blade failure in 2006 involving a commercial Bombardier Global Express XRS (GE XRS)–an event from which the crew was able to recover and land safely. The GE XRS is identical to the E-11A except for the cockpit.

“The pilot in command of the GE XRS in the Global Express event reported the first moments following blade separation as disorienting initially, with airframe vibrations of such magnitude as to lead the crew to wonder if they had experienced a mid-air collision,” according to the AIB report. “He described a loud bang, and sustained vibration through the rest of the flight, sufficient to break stemware in the galley. The pilot in command also stated that he could not determine which engine had failed based on aircraft vibration and sensation alone without looking at the

According to the AIB, the “overall vibrations” in the fatal crash of the E-11A in Afghanistan last Jan. 27 were 25 percent greater than the vibrations in the 2006 GE XRS event–a situation that made it more likely that the E-11A crew “perceived the event as severe and concluded they needed to react immediately.”