In late January 2020 a little known aircraft type, the E-11A, made the news when this vital American support aircraft suffered equipment problems and crashed in Afghanistan. This occurred in southeast Afghanistan (Ghazni province) where a lot of Taliban, pro-government tribesmen plus Afghan and American troops were active. The E-11A electronic support aircraft crashed because of equipment problems. The aircraft apparently attempted an emergency landing as the aircraft skidded quite a distance before bursting into flames, killing the pilots and destroying most of the specialized communications equipment carried. While the landing area was nominally under Taliban control since 2015, pro-government tribesmen and American troops quickly showed up.
E-11A is a twin-engine business jet filled with electronics, mainly communications equipment which enables the E-11A to serve as the equivalent of a communications satellite. This lets American and allied ground and air forces communicate freely without worrying about the interference Afghanistan’s many mountains create for most types of wireless communications. Ground troops can quickly report enemy activity and call in air support or ground reinforcements. In effect, the E-11A provides Afghan and foreign troops with more effective communications than the Taliban or drug gangs. The bad guys can use satellite phones but these are very expensive and detectable.
Four (now three) E-11As and three EQ-4Bs are the BACN (Battlefield Airborne Communications Node) force that is crucial to quickly linking air controllers on the ground with warplanes in the area. Some of these aircraft are available to provide support (usually in the form of smart bombs or missiles). Most of the airstrikes carried out in Afghanistan involve using BACN. Because of this, the BACN aircraft operate 24/7 over Afghanistan to speed up the delivery of air support and better communications in general.
The need for BACN became obvious soon after American forces entered Afghanistan in late 2001. By 2005 a test version of BACN was sent to Afghanistan and performed as predicted. By 2008 the first E-11A was in service and was soon followed by the first UAV version. In 2011 the air force assigned new designations (E-11A and EQ-4B) to the manned aircraft and UAVs that have been operating as communications satellite substitutes.
The E-11A was actually a 44 ton BD 700 twin-engine business jet and the EQ-4B a BACN equipped RQ-4B Global Hawk UAV. Since 2008 BACN service has been available over 98 percent of the time to provide communications relay services over Afghanistan.
Both E-11A and EQ-4B carry the same BACN equipment, which operates largely on automatic without any human intervention by anyone in the air. Human support is provided by technical personnel on the ground.
The BACN software does more than just act as a comm satellite. In order to make it possible for ground troops to not only talk to others farther away (anywhere, in fact), it also enables ground troops to quickly connect with other military aircraft combat and support) overhead. This is done with software that automatically transfers the data between the normally incompatible radio equipment aircraft and ground troops use. BACN also provides communications between aircraft. BACN not only provides ground troops with unlimited communications range but also handles linking normally incompatible communications systems with each other. BACN also provides a substitute for satellite communications which, ten years ago, was in short supply for troops in Afghanistan and that was one reason for creating BACN.
The E-11A can stay in the air for over ten hours per sortie, while the EQ-4B can do more than twice that. Both fly at 12,900 meters (40,000 feet). The E-11A entered service first, followed about a year later by the EQ-4B. Currently, there are three E-11As still operational and three EQ-4Bs in service over Afghanistan. These BACN aircraft have not been needed anywhere else, mainly because no other combat zone has the many high mountains and numerous valleys where normal military communications are often blocked.
The E-11A is used when you have to get some BACN capability somewhere in an area that might require some skilled piloting. The EQ-4B is for when you want to keep the BACN capability going someplace 24/7 and you have time for the EQ-4B ground controllers to deal with the details.
BACN is not a new idea for the air force. In 2003, realizing that every aerial battlefield in the past few decades has featured several KC-135 tankers circling, waiting to refuel a thirsty warplane, the U.S. Air Force gave the tankers an additional job. By adding a few hundred kilograms (220 pounds) of electronics mounted on a cargo pallet, which KC-135s are equipped to handle, the tanker was turned into a node in an aerial communications network. This solved the problem of how to connect warplanes to the new battlefield Internet when those planes do not have satellite communications capability. The aircraft use line-of-sight communications, which cannot connect with any ground station or aircraft that is over the horizon or behind a mountain. The system, called ROBE (Roll-On Beyond-line-of-sight Enhancement), was particularly useful in a mountainous area like Afghanistan. After the first 20 ROBE units, costing about $900,000 each, entered service, an upgraded model was introduced three years ago. The Department of Defense and NATO have already developed standards (LINK 16) for the transfer of video, picture and data electronically between ground stations, aircraft and ships using radio or satellite communications networks. KC-135s can't use BACN because they normally fly lower, at about 6,700 meters (20,000 feet) than required to truly act as a satellite substitute. Moreover, there are some mountains in Afghanistan higher than the KC-135 “working altitude).” The air force is developing a much improved version of ROBE to provide more aerial support functions for surveillance and EW (Electronic Warfare) work as well as operating as a communications node.