No, this doesn’t involve a trip to the Arklay mountains. Today, we’re looking into aerial systems for monitoring ground combat and enemy forces, also known as ISR (Intelligence, Surveillance, and Reconnaissance). This is an often-overlooked capability, and while such systems are not foolproof, not having them can lead to a lot of embarrassment. The notion was a key part of late-Cold War Airland Battle tactics, where ISR platforms could provide targeting data for long range weapons to atrit Soviet forces before they made contact with friendly ground troops.

In terms of current capabilities, the United States has the only serious capability worth writing home about, using the E-8C JSTARS. These put a powerful, GMTI/SAR capable radar on a Boeing 707 airframe. They have proven to be extremely effective when deployed, and were sorely missed by the Europeans during their recent Libya “intervention.”¹ Of course, we can’t just buy these, because the 707 is long since out of production. Also, the USAF hasn’t really decided how it wants to proceed to replace or recondition the E-8Cs. We’ll look at other people’s ISR platforms as well as things that were proposed to replace the JSTARS.

The UK operates four Sentinel R1s, built by adding the appropriate radar systems to a Bombardier Global Express business jet. This is a relatively low-cost airframe, being a business jet, though the usual UK small orders means the net result is still going to be expensive. Also, lots of the analysis and battle management workstations are ground-based, for better and for worse. A Global Express 6000 derivative was one of the proposals for a JSTARS replacement.

Brazil has deployed three R-99s, ERJ-145 conversions with the appropriate SAR capable radar, to monitor illicit narcotics tracking and other illegal activities in the Amazon basin as part of the SIVAM. Unfortunately, I don’t know that much about the radar system deployed, and this one wasn’t proposed for the JSTARS replacement, so it’s not using that particular radar package.

Gulfstream also has an offering to replace the JSTARS that is based on their G550 SEMA variant, though with more radar focus than EW-focus. The SEMA version of the G550 is in use by the Israeli air force and has recently been purchased by Australia. There’s also a significantly reworked G550 variant, originally used with Conformal Early Warning² arrays by the Israeli air force in the AEW&C role. The CAEW variant has also been purchased by the US Navy for monitoring their missile test ranges, and is to be reworked by L3 with electronic warfare systems in the conformal fairings to replace the EC-130H Compass Call in USAF service.

Boeing has a 737-derivative, which is pretty similar to the P-8, other than having a radar optimized for a different mission. Radar options for the JSTARS replacement proposal were similar to those of the bizjets. Annoyingly, the product page for this is no longer on Boeing’s website. The strangest thing about Boeing’s proposal (sparse as the details are) is that it didn’t do all that much to take advantage of the extra space, weight, and power capabilities of the 737 platform.

At the end of the day, 8-10 analysts doesn’t require a 737, and if you’re not going to load it up with a big radar, you can go with a smaller, more fuel-efficient jet.

Let’s also talk about the Global Hawk. The RQ-4B Block 40/RQ-4D variants come equipped with a small version of the MP-RTIP radar originally intended for the E-10A. That’s a pretty fantastic radar, and the RQ-4D³ is the highest-flying option. It does not operate in adverse weather conditions though.

Alright, let’s get picking. We’re going to want some RQ-4Ds because of that fantastic radar and because it’s a pretty natural fit for a UAV. There’s a big NATO buy at the moment, and we’d like to get in on that model. We’re also going to want a manned option though, which means we’re going to have to sort through the business jet contenders. In terms of radar systems, all of the JSTARS replacement offerings had a similar radar fit, which doesn’t help us much. According to the Business & Commercial Aviation 2018 buyer’s guide, the G550 is a little cheaper than the Global Express 6000, but the difference is probably too small to matter.

What is different is that there are a lot more military G550 variants in service. There’s also the flight tested CAEW airframe, which is useful for a few other purposes besides the AEW&C role it was originally intended for. So we’ll go with that one, since it gives us a few more options for related aircraft down the line. We especially like the idea of an electronic attack version.

Today we’re talking maritime patrol aircraft. There are two on the market worth looking at: Boeing’s P-8 Poseidon and Kawasaki’s P-1. Let’s look at them both and see what we like.

The Poseidon was designed to replace the P-3 Orion, and the P-8 is based on the Boeing 737-800ERX, which means it has the fuselage from the 737-800 and the wings from the 737-900. So it’s based on a recent model of a very popular airliner, which keeps airframe costs down and ensures a good supply of future spare parts. The Poseidon has a weapons bay located behind the wing, with five weapons hardpoints. An additional six hardpoints are under the wings. This bay might seem a little small, but you can’t actually put the bay between the wings, because that’s where the structure is to support the wings.

Sensorwise, the P-8A is equipped with the APY-10 multi-mission surface search radar, plus facilities for a large number of sonobuoys, and an EO/IR ball turret. It even has a sensor to detect emissions from diesel ships and submarines. In its standard, USN model, it does not have a magnetic anomaly detector (MAD). This was per a NAVAIR request to reduce weight and improve range. It also allows for a higher-altitude flight profile that is more fuel efficient, especially for an airliner-derived platform. In turn, the lack of MAD has been frequently criticized. It should be noted that this shouldn’t be seen as an indictment of the platform; regardless of what you think of the US Navy’s decision the P-8 can be equipped with a MAD, and the version for India has been sold with one.

The P-1 was also designed to replace the Orion, and it took a notably different path. It’s about the same size as the Poseidon, but it’s optimized for lower-altitude flying, with less-swept wings. It’s equipped with advanced avionics, including a fly-by-light flight control system, an HPS-106 AESA surveillance radar, and a magnetic anomaly detector standard. It has eight internal and eight external hardpoints for weapons. It does not have provision for midair refueling.

In terms of comparatives, the P-1 has more weapons capacity, and flies the traditional lower altitudes of the P-3 Orion. The P-8 is a higher altitude aircraft, for better and for worse. The P-8 has a big edge in terms of costs, being based on a currently-produced airliner, being in higher-rate production, and having tons of spares readily available. The popularity of the 737 platform will mean that there will be a large supply of future spares too.

And, like everyone else who has looked at these two, we’re going with Poseidon. Which begs the question, to MAD or not to MAD? I’m going to hedge here, because I really want to see some data or some test results, but I don’t have them as an armchair strategist. I’ll tentatively say “With MAD”, understanding that I’m open to data that I don’t have right now showing that it’s really not needed.

Airborne Early Warning and Control (AEW&C, often colloquially called AWACS even though that’s a specific system for the role) is what separates the Serious Air Forces from the cut-rate posers. The idea is to take a large airframe, usually a jetliner, put a big radar on it, and then have a bunch of people sitting at computers to coordinate your sorties. All the benefits of GCI in a portable package!

A large part of picking a platform is determining your constraints. We’re looking for a land-based platform that’s relatively low cost to operate and can handle a good number of friendly and enemy aircraft. For this reason, we’re going to look at the larger class of AEW&C platforms.

As a brief aside, the smaller platforms are the Northrop Grumman E-2 Hawkeye, and a number of business jet derivatives. The Hawkeye is the only decent carrierborne AEW&C platform available, so if we were looking to build a naval air arm, that’s what we’d pick for the purpose.

The obvious large AEW&C platform is the E-3 Sentry. However, it is built on a Boeing 707-derived airframe, and these are no longer in production. No luck there. This problem also presented itself to the Japanese when they were looking for a larger platform to supplement their Hawkeyes in the 1990s.

Boeing obliged with the E-767, which puts the radar and computers from the E-3 onto a 767-200 airframe. The resulting widebody has space for up to 19 controller consoles, though I couldn’t find a great source on how many the JASDF use. It still uses the same radar as on the Sentry, albeit with upgrades. Also, as presently configured, it has no aerial refueling capability.

About a decade later, Boeing responded to an Australian RFP with a new design: the E-7A Wedgetail. This aircraft is based on the 737-700 airframe, and mounts Northrop Grumman’s Multirole Electronically Scanned Array radar. This is an actively scanned array, so it doesn’t need to rotate. It does posses aerial refueling capability, and is capable of mounting up to twelve controller consoles. At present, Australia has fitted ten consoles.

In terms of bigger platforms, these are the contenders. More consoles on the E-767 means it can coordinate more friendly aircraft. The more advanced MESA radar on the Wedgetail lets it refresh scans of regions faster and adjust power to focus on particular sectors with longer-ranged scans. It’s also able to handle simultaneous air and surface search. and the actively scanned array should be better at ECCM.

You can probably see where this is going. We’re opting for the E-7A Wedgetail. It’s even the cheaper option of the two. It’s telling that Wedgetail has had several export successes since being sold to the Australians. It’s also telling that the E-767 is absent from most of Boeing’s current marketing materials.

Tanker aircraft are a requirement for any serious projection of airpower. And no one ever has enough of them. So let’s go get some.

Previously, the standard in aerial refueling was the KC-135, a close relative of the classic Boeing 707. Today, there are two different airframes available for tankers. There is the Boeing 767 and the Airbus A330. The 767 has two tanker derivatives: the KC-767, which is derived from the 767-200ER and is in use by Italy and Japan; and the KC-46A, which is based on the 767-200LRF¹ and is in use by the United States and Japan. Note that the KC-46A is bigger than the KC-767, and carries more fuel. The A330-MRTT is the tanker derivative of the A330, and it is bigger than the KC-46A.

Now on to the choices. We know from the USAF tanker proposals that the 767 options have a lower projected life cycle cost than the A330-MRTT. For many export customers, this is outweighed by the greater fuel and cargo capacity of the Airbus. On the other hand, the 767s smaller size means it can operate out of smaller airfields. It is closer in size to the KC-135R, for those looking for a direct replacement, or just trying to picture sizes.

For us, we’d also point out the massive USAF buy of KC-46As as points in its favor, since that will mean the type will get more future upgrades and development money, if only to keep the US fleet going. Further, 767s are Boeing aircraft, and have a flight envelope not restricted by the flight computer. We prefer this.

So we’re going with the KC-46A. It’ll get the upgrades, and Boeing is still making 767s for the civilian market, which is a plus. We expect to be able to cannibalize ex-civilian airliners for parts and airframes for years after the type is formally retired (as was done with the KC-135), but the longer we can go before having to do this the better.