NITPICK: SUPER HORNET IRST

 

[Welcome to "NITPICK"!  For the next few weeks I will be examining a single aspect of the potential fighters that just drives me nuts.  These are not dealbreakers, or even major flaws.  They are simply one aspect of the aircraft THAT COULD HAVE BEEN DONE BETTER.]

Something has been bugging me about the Super Hornet Block III.  

In the grand scheme of things, it is pretty minor.  For most intents and purposes, it is all but insignificant.  

But it DOES bug me.  (Pardon the pun)

The Super Hornet Block III adds multitude of improvements over the "vanilla" Super Hornet.  Better avionics and cockpit displays, conformal fuel tanks, and an IRST option.  All-in-all, a fantastic upgrade.  

Except...

Look at this picture of an early Block III demonstrator:

Look how sleek it is!  No bulky external fuel tanks.  No targeting pods, no nothing.  Yet it still carries substantial quantities of fuel.  Even a "combat ready" version would not necessarily be too different with an AIM-9 Sidewinder on each wingtip and two AMRAAMs stowed semi-conformally on the fuselage.  

This relatively "clean" configuration would offer real-world improvements over previous Super Hornets' aerodynamic drag and radar cross section (RCS).

Very cool.

Except for ONE thing.  They forgot to put an IRST on there, somewhere.  

Early Block III (initially marketed as "International Roadmap") Super Hornets promised "internal IRST". Mock-ups showed off what looks like a facsimile of the F-35's EOTS under its nose.  (The EOTS operates more akin to a Sniper targeting pod, but whatever...)  This, like the proposed enclosed weapon pods, did not seem to make it much past the drawing board.  

We can somewhat excuse the Block III's lack of internal IRST.  For one, there may not be adequate room to house the additional equipment needed...  Although Saab managed to cram an internal IRST into the much smaller Gripen.  

It is more likely that Boeing, finding a luke-warm reception to new-build Block III Super Hornets, decided instead to offer the the Block III as an upgrade to existing Super Hornets.  This would shift the focus towards simpler external upgrades, rather than having to extensively refit hundreds of aircraft.  

Fair enough.  

Boeing's eventual solution to its IRST ended up being rather interesting:  Rather than reworking the aircraft's internals, an external IRST pod would be added.  

External IRSTs are fairly new in the world of combat aviation.  They allow older fighters like the F-15 and F-16 to be easily retrofitted with passive detection capabilities.  The only real disadvantage is that they take up a weapon hardpoint and add to the aircraft's drag and RCS.  

The Super Hornet's IRST solution goes one better:  It combines both external IRST and external centre-line fuel tank. This gives the aircraft additional range and additional detection capabilities.  

It is a great idea in theory.  Indeed, one hopes that the system will find itself on other fighter aircraft as well.  

BUT IT BUGS ME ON THE BLOCK III SUPER HORNET.  

Why?  Because adding that extra fuel seems completely redundant when the Block III already adds the equivalent of two external tanks!  

The Super Hornet already adds substantially more fuel and range to the legacy Hornet.  Add on CFTs and the range goes up even further.  Now add a centerline fuel tank and the range goes up almost ridiculous levels...  All before adding a signal traditional drop tank.  

More range is always a good thing, but one wonders if it will always be necessary to drag along the equivalent of THREE additional external tanks.  If it is not necessary, TOO BAD.  Those CFTs take a lot of work to remove and removing the centerline tank removes your IRST.  None of them are jettisonable.  

Look at this artist's rendering of the Block III Super Hornet in RCAF livery.  Not bad...  It certainly looks intimidating with 12 (count 'em) AMRAAMs and 2 Sidewinders.  

Too bad about that belly tank though.  It just sort of...  Hangs there.  

What is the point of developing CFTs only to add an additional tank in order to take advantage of IRST capability?

Here is a thought...  Instead of adding that IRST to an external fuel tank, why not add that IRST to one of the conformal fuel tanks?

This would have several advantages.  Adding IRST to the CFTs would free up that center pylon, allowing more options in mounting additional weapons, fuel, or sensor pods.  It would also give the IRST sensor a clearer field of view above by being mounted on the top of the aircraft (Most IRSTs are mounted at the base of the canopy for this reason.)  This would also minimize drag and RCS.  Traditional external tanks would still be an option, just not a necessity.  

Something like this:

(Please excuse my terrible photo editing skills)

Adding an IRST to a belly tank is a novel work-around, but Boeing really missed a golden opportunity to implement a much more elegant solution.  More than likely, this is due to "compartmentalizing".  Boeing assigned one "team" with the task of adding additional conformal fuel tanks to the Super Hornet, while another team was tasked with adding an IRST.  

Too bad they never got together to add a solution that would have done both at the same time.