Why the Super Bug is no substitute for the F-35, Part 2
Posted by zbigniewmazurak on September 12, 2012
A previous post on this website demonstrated why the F/A-18E/F Super Bug is technologically inferior to, and therefore no substitute for, the F-35, which is planned to replace fleets of aging tactical aircraft across the USN, USMC, and USAF.
Today, we will compare the Super Bug to its most likely short-term competitors – variants of the Su-30/J-11 Flanker – and see whether it can defeat them. The analysis will show whether the Super Bug can act as a substitute for the F-35, which is intended to be the premier strike fighter of the USN and USMC for decades to come.
But first: what is the Super Bug, and what is the Flanker?
The Super Bug is basically a larger-fuselage evolution of the F/A-18 Hornet, a plane that first flew in the 1970s and entered service in 1983. It is larger and has a more powerful radar (the APG-79 AESA radar) as well as some radar signature reductions such as inlet geometry shaping, inlet tunnel S-bends, and an AESA shroud, all of which have reduced its radar signature compared to the original Hornet and made it much smaller than that of a Flanker without stealth coatings.
But the Super Bug is not (and was never designed to be) a real fighter, let alone an air superiority fighter. It is, and was always designed to be, a lightweight strike aircraft intended to attack ground targets in sanitized airspace – that is, one enemy fighters and air defenses were already eliminated by other American weapons.
It has a poor thrust to weight ratio of 0.93:1 (i.e. it weighs more than the force of its engines, even on afterburner). It has a very low internal fuel capacity (14,400 lb). It can sustain only 7.6G. It can carry only a moderate amount of ordnance, and only to a distance of 390 nm (its combat radius, severely limited by its low fuel capacity). Its wing loading ratio, at 459 kg/sq ft, is much higher than that of any Flanker variant.
Here’s a table comparing the Super Bug’s most important technical parameters to those of various Flanker variants as well as the PAKFA and the J-20:
|Dry thrust (kN)||62.3×2||86.3×2||89.17×2||NA||NA||74.5×2||74.5×2|
|Thrust w/afterburner (kN)||97.9×2||142×2||129.4×2||157+x2||180||122.5×2||125.5×2|
|Max speed (Mach)||1.8||2.25||2.35||2+||2||2||2.17|
|Combat radius (km)||390 nm||NA||NA||NA||2000||NA||NA|
|Service ceiling (ft)||50000||59100||62523||65600||65617||56800||NA|
|Rate of climb (m/s)||228||280+||300||350||N/A||230||246|
|Wing loading (kg/m2)||459||408||385||330-470||N/A||401||483|
|Number of weapons carried (max)||11||12||10||10||N/A||12||12|
|Internal fuel capacity (lb)||14400||22711|
As you can see from the table, almost all Flanker variants (except the Su-33) outperform the Super Bug in almost every criterion of kinematic and aerodynamic performance, in most cases by huge margins, as does the PAKFA and (where information is available) China’s 5th generation fighter, the J-20.
These adversary aircraft can fly much higher (no lower than 56.8 angels, and up to 65.6 angels), faster (2-2.25 Mach vs the Super Bug’s Mach 1.8 top speed), and farther than the Super Bug, which means that, in a combat situation, they could launch their anti-ship or air to air missiles from a range (and altitude) beyond the Super Bug’s reach, and by flying high, they would dramatically increase the nominal range of their missiles. In a close combat situation, they can easily outturn the Super Bug with their superior G limit (turning capability) and much better thrust-to-weight and wing loading ratios. The only exception to this rule is the least-proliferated Flanker variant – the carrier-borne Su-33, currently serving only on Russia’s Admiral Kuznetsov aircraft carrier – which has a lower T/W and a higher wing loading ratio than the Super Bug.
Moreover, the J-11 and the PAKFA can carry one weapon fewer than the Super Bug.
Otherwise, all of these aircraft are decisively superior to the Super Bug in all criteria.
As stated earlier, the Super Bug features signature reduction capabilities which give it a smaller RCS than that of a Flanker not modified with stealth coatings. But the Russians and the Chinese are already working on that, and giving the Flanker such coatings will negate the Super Bug’s sole remaining advantage.
The Super Bug’s APG-79 radar is more powerful than the ones found on Flankers not fitted with the Irbis-E AESA or the Zhuk ESA radar (i.e. on early Flanker variants), but decisively inferior to the Irbis-E and the Zhuk, which is standard issue on the newest variants, such as the Su-33, J-11, and Su-35, and to the newest Chinese radars.
“In assessing the Flanker against the Super Hornet it is clear from the outset that the advantage in firepower, speed, raw agility, range and manoeuvre performance goes to the Flanker. Given that operational Flankers span variants from B through H, and type designations from Su-27S, through Su-30s to Su-35s, there are a wide range of configurations possible.
This has been further complicated by the Russian propensity to customise configurations for clients, and perform ongoing technology upgrades to operational variants. Another byproduct of Russian marketing is that the label Su-30 spans an upgraded Su-27SKM (Su-30KI) up to the Indian Su-30MKI, which uses extensive ly features demonstrated in the Su-37.
In terms of aerodynamic performance the Flanker sits broadly in the class of the F-15 family, with similar thrust / weight ratios at similar weights. The empty weight of Flanker variants ranges between 37,240 – 40,800 lb and internal fuel capacities between 20,750 – 22,600 lb.(…)
High speed turning performance, where thrust limited, also goes to the Flanker, as does supersonic manoeuvre performance. The Super Hornet is severely handicapped by its lower combat thrust/weight ratio, and hybrid wing planform. It is worth observing that high alpha trim drag and pitch rates of the canard equipped Flanker variants, such as the Su-33 and Su-30MKI, will be superior to the versions without canards.(…)
With Al-41F engines installed the Flanker’s robust margin in kinematic performance against the Super Hornet grows considerably in all regimes of flight – it provides the Flanker with ‘F-22-like’ raw agility and performance. With wing sweep, planform, forebody shaping and inlets built for Mach 2+ dash, a clean Flanker with Al-41Fs should supercruise effectively. A supercruising Flanker with TVC nozzles, ie AL-41FU, can use downward TVC to offset supersonic trim drag and thus achieve lower fuel burn in this regime.(…)
In terms of combat radius performance the Flanker outperforms the Super Hornet, even with the latter carrying external tanks. There is no substitute for clean internal fuel. The Flanker’s radar aperture is twice the size of the Hornet family apertures, due to the larger nose cross section.(…)
In summary, the Flanker outperforms the Super Hornet decisively in aerodynamic performance. What advantage the Super Hornet now has in the APG-79 radar will vanish in coming years as Russian AESAs emerge. The one area in which the Flanker currently trails the Super Hornet is in radar signature (stealth) performance. The Super Hornet has inlet geometry shaping, inlet tunnel S-bends, and an AESA shroud all of which reduce its forward sector signature well below that of the Flanker.
In the short term, this is an advantage the Super Hornet retains, with the caveat that external stores put hard limits on signature improvement for the Super Hornet. However, Russian researchers have done some excellent work over the last decade in absorbent materials and laminate techniques for radar signature reduction, which offer the potential for the Flanker to achieve similar signature reduction to the F/A-18E/F. If funded, a reduced signature Flanker is feasible in the next half decade.
In conclusion, the Flanker in all current variants kinematically outclasses the Super Hornet in all high performance flight regimes. The only near term advantage the latest Super Hornets have over legacy Flanker variants is in the APG-79 AESA and radar signature reduction features, an advantage which will not last long given highly active ongoing Russian development effort in these areas. The supercruising Al-41F engine will further widen the performance gap in favour of the Flanker. What this means is that post 2010 the Super Hornet is uncompetitive against advanced Flankers in BVR combat, as it is now uncompetitive in close combat.”
And remember: Dr Kopp wrote this in 2007, 5 years ago. Russian and Chinese military technology has progressed greatly since then.
In short, in all criteria except RCS, the Super Bug is decisively inferior to virtually all Flanker variants and to the PAKFA and the J-20. And it’s no surprise to those of us who are knowledgeable about defense issues. The Flanker was always intended to be an air superiority fighter – the Russian response to the F-15 – while the PAKFA and the J-20 are the Russian and the Chinese response to the F-22. The USN and the USMC would be well advised to stop wasting money on the procurement of further Super Bugs and instead use it to hasten the development and introduction of the F-35 – or better yet, develop a navalized and a STOVL version of the Raptor as Dr Kopp has suggested.
In any case, the fact is that the Super Bug is no substitute for the F-35.