The U.S. military rightly understands that the rapid transfer of information across the battlefield can give American forces a decided edge against its opponents. Over the years, the different services have adopted a variety of manned and unmanned aircraft with increasingly advanced communications gear and data-links, but haven't always upgraded older types, creating a complex web of different systems that often can't "talk" to each other directly. Now we at The War Zone have discovered a single master diagram that offers an amazingly granular picture of how various U.S. military combat and combat support aircraft, including the secretive RQ-170 Sentinel drone, can or can't communicate. U.S. Air Force Major Michael Smith included the chart, titled "Integrated Airborne/Ground Net Enabled Warfare, Version 5.2" and dated May 2017, in a briefing he presented at the National Defense Industry Association's Precision Strike Annual Review on March 20, 2018. Smith is the Chief of Weapons and Tactics for the 720th Special Tactics Group, which is part of Air Force Special Operations Command and oversees the bulk of the special tactics airmen assigned to that command.

These individuals include Combat Controllers, Joint Tactical Air Controllers, and others, who variously coordinate air strikes and air drops, manage airfield operations and communications at austere locations, and often assist with mission planning, among various other specialized duties. It's no surprise special tactics personnel have to have a good working understanding of the communications and data sharing capabilities of various aircraft. Prominently at the top of the chart are depictions of what aircraft have one of three common data links, Link 16, Situational Awareness Data Link (SADL), and Variable Message Format (VMF). On U.S. military aircraft, Link 16 eclipses the use of both SADL and VMF and the diagram notes that there are plans to add Link 16 capability to more than a dozen in-service types, such as the Marine Corps AH-1Z gunship helicopters and MV-22 Osprey tilt-rotors and the entire U.S. Army special operations helicopter fleet, between the 2017 and 2020 fiscal years.

USAF The chart US Air Force Major Smith included in his March 2018 briefing, which has a number of immediately obvious errors, such as the "KC-135J" and "MQ-1C Predator," but still has a wealth of other information.

USAF According to the chart, AC-130J Ghostrider gunships, such as the one seen here, have Link 16, SADL, and VMF data links.

Of particular interest is the inclusion of the top secret RQ-170, which the U.S. military has released very little information about since it officially acknowledged its existence in 2009. According to this chart, it is one of the few aircraft that carries Link 16 and SADL, though it's not entirely clear why it would need both systems. We do know that the Air Force has employed Sentinels for persistent surveillance in denied areas and in an overwatch role supporting forces on the ground, and has considered using them for bomb damage assessment in high-risk scenarios. Having both systems could give them added flexibility to communicate with other aircraft and ground-based elements. But neither of these data links are stealthy in nature, but the RQ-170 could use them passively, sucking up their transmissions and sending that information around the world via its low-probability of intercept (LPI) microwave SATCOM communications systems. When operating over lower threat territory, it could use Link 16 and SADL actively for two-way data exchanges. And clearly, the Sentinel possesses other classified communications capabilities that are not featured on this chart. If the aircraft's had both of those data links installed since its official disclosure, the security of those systems might have been compromised following the crash of a Sentinel in Iran 2011. In addition to attempting to reverse engineer the design, the Iranians allowed their foreign partners, namely the Russians and the Chinese, to closely examine the largely intact aircraft.

USAF via FOIA An RQ-170 Sentinel.

It's worth pointing out that the chart makes little mention of stealthy data links at all, only listing the F-35's stealthy Multifunction Advanced Data Link (MADL) and the F-22's unique Intra-Flight Data Link (IFDL) specifically. At the same time, the B-2 Spirit and the future B-21 Raider stealth bombers are simply listed as having Link 16 connectivity. The Air Force plans to integrate the F-35's MADL onto the B-2 and the B-21 will get the same. On top of that, we know that the F-35 has full Link 16 capability. Creative tactics could allow for it to be used even while operating in stealth mode by passing information over a MADL's directional 'daisy chain' and then having the F-35 farthest from the leading-edge of combat rebroadcast that data in Link 16 waveform for other aircraft to exploit.

Lockheed slide

The F-22 also has Link 16, but with receive-only capability. The F-15C's 'Talon HATE' pod aims to connect the F-22 with Link 16 and the outside 'tactical world' at large. The chart, however, incorrectly says F-16s carry this system. The Ku-band satcom section only mentions the MQ-1 Predator, MQ-1C Gray Eagle, and MQ-9 Reaper drones, despite many more aircraft, such as AC-130 gunships and MC-130 special operations transports, having this type of connectivity. The RQ-170 is also missing, but this is unsurprising as it is not publically known exactly what type of SATCOM system it uses.

USAF Lockheed Martin converted this U-2S Dragon Lady into a flying communications hub for the U.S. Air Force on an experimental basis.