Unmanned Carrier Aircraft (UCLASS)

The Navy is working to develop a carrier based, unmanned strike aircraft.  This Unmanned Carrier Launched Airborne Surveillance and Strike (UCLASS) aircraft would provide long range, stealthy strike capability for use in the Anti-Access/Area Denial (A2/AD) scenario.

Before I go any further, let me say this up front - I'm not against UCLASS, at all.  Potentially, they could be very useful.  However, the basic concept as applied to the Chinese A2/AD scenario has some serious challenges to overcome that deserve to be discussed in the face of the Navy’s typical rush to acquisition.  Just as with “littoral” and “AirSea Battle”, I fear that the Navy is latching onto “UCLASS” as another acquisition justification buzzword without adequately exploring the underlying concept. 



UCLASS - The Right Concept?



Let’s take a closer look at the underlying concept.  The Chinese A2/AD zone is visualized as being about 1000 nm out from the mainland.  So, assuming a launch from outside the zone against targets on or deep inside the mainland, an aircraft would need to be able to fly 1000-1500 nm.  Of course, the range of the weapon carried by the aircraft could extend the effective striking range of the UCLASS.  During the course of penetration, the UCLASS would have to pass through many radar zones, hundreds of patrolling aircraft, and hundreds of ground AAA and SAM installations. 



So, we can see that a UCLASS needs extraordinary range, something on the order of a combat radius of 1000-1500 nm.  It will also need highly effective stealth and/or great speed to avoid or outrun threats.  Finally, it would be nice if the payload were greater than one or two weapons.  Having flown many hundreds of miles and evaded hundreds of threats it would be silly to only be able to strike one or two targets.  The risk/reward balance just isn’t there without a much greater payload.  And, lest we’ve forgotten, the UCLASS has to be small enough to fit on a carrier.

The Navy’s current prototype UCLASS is the X-47B Pegasus.  Here’s some of the relevant specifications.

Range (one way) – 2100 nm

Combat Radius (estimated) – 500 nm

Weapons Load – 4500 lb

Speed – subsonic

Cruise – 0.45 mach

Wingspan – 62 ft (31 ft folded)

Comparing the X-47B specs to our desired performance, we can see that the prototype’s combat radius is half to one third of that needed.  Remember, that the A2/AD zone is, essentially, all water.  The targets of interest, aside from the occasional ship, are all on the mainland.  Penetrating half way accomplishes nothing.  Of course, this is a prototype so the range can be increased, right?  Well, yes, but longer range means bigger fuel storage which means a bigger, heavier aircraft and the bigger it is, the harder it’s going to be to operate and fit on a carrier.  The prototype is already larger than an F/A-18E/F Super Hornet (wingspan = 44 ft).  The largest aircraft currently on carriers is the E-2 Hawkeye with a wingspan of 80 ft. 

You may be observing that the range is 2100 nm and thinking that’s a 1050 nm round trip.  That should be plenty of range, right?  You’d be correct except that range is non-combat loaded and assumes a straight line course at the most economical speed and altitude profile.  Adding roundabout waypoints to avoid high threat areas, adding a combat weapons load, and performing evasive or high speed avoidance maneuvers seriously cuts into the range, hence, the estimate of a 500 nm combat radius.  If you don’t believe this, go check out the Hornet’s (or any plane’s) range versus combat radius figures.

Speed is the next obvious deficiency.  A subsonic aircraft (only about 350 kts cruising speed) is going to have a hard time penetrating a thousand mile A2/AD zone and escaping threats along the way.  Let’s be blunt – it can’t.  Unfortunately, there’s a Catch-22 at work, here.  The only way to make the aircraft faster is to increase fuel consumption which decreases the combat radius which leads us right back to having to make a significantly bigger aircraft to carry much more fuel.

Finally, weapons load is extremely light.  The current F/A-18E/F has a weapons capacity of 17,500 lbs which is way bigger than the X-47B’s 4500 lbs.  Again, the only way to increase the payload is to make the aircraft bigger. 

Do you see the trend, here?  The only way to meet the notional requirements for a useful UCLASS is to make it much bigger.  I guess there’s a reason why the B-1 and B-2 deep penetration bombers are so big.

Of course, bigger creates its own set of problems.  The bigger the aircraft, the easier it is to detect.  The bigger the aircraft, the fewer can fit on a carrier.  The bigger the aircraft, the more expensive it is.

Have we left any issues out?  Yes, we have!  How about remote control communications?  Our ability to control UAVs at any distance is currently suspect and at the 1000 + nm ranges that a UCLASS would have to operate, maintaining reliable control communications becomes highly problematic.  In a war, communications satellites and relay nodes will likely be destroyed and heavy jamming will be the norm.  A successful UCLASS will have to overcome those communication challenges.

Closely related to communications is the issue of location awareness.  How will the UCLASS know where it is if GPS satellites go down at the start of conflict as everyone assumes they will?  To be fair, this problem is not unique to the UCLASS but affects every weapon and platform in the US military.  Still, there’s no point penetrating an A2/AD zone if you don’t know precisely where you are. 

I could go on but this serves to illustrate that the basic concept of a long range UCLASS is suspect under the current operating concept and technological capabilities.  A viable UCLASS would need closer to 2000 nm combat radius, much greater stealth or much greater speed to avoid detection/destruction, larger weapons carrying capacity, and reliable control communications over thousands of miles.

Can the Navy get from the initial data point of the X-47B to the desired aircraft?  Possibly, though the challenges are great.  The purpose of this discussion is to point out the magnitude of the challenges and suggest that the Navy not leap into this without addressing the problems and thinking them through.  Failure to do so is what led to the LCS and no one wants to see the flying version of the LCS!