Search the Internet for material on the JSF and you will find terabyte after terabyte of articles, pictures, Powerpoint presentations, PDFs, tables and laudatory Blogs. And how much relates to how the JSF will deliver this capability? You will find assertions and statement such as ‘six times better Relative Loss Exchange Ratio than legacy aircraft’ , or ‘The operational arguments focus on combat effectiveness against top foreign fighter aircraft such as the Russian Su-27 and MiG-29. Lockheed Martin and USAF analysts put the loss-exchange ratio at 30-1 for the F-22, 3-1 for the F-35 and 1-1 or less for the F-15, F/A-18 and F-16’[2
And how will the F-35 JSF perform, not against truly obsolete legacy aircraft like the Su-27SK and the MiG-29, but against modern fighters like the Su-35S? We can answer these questions with a head-to-head analysis of the two aircraft.
Air combat is a complex mix of art, science and engineering. Aircraft performance, weapons performance, networked sensors and pilot skill all contribute to the final Loss Exchange Ratio (LER). The only simplification is that aircraft approach, engage in combat and the survivors depart. This activity can be examined in a ‘kill-chain’ with the following stages: ‘Detect-Identify-Engage-Disengage-Destroy’ (DIED2).
Here is a scenario. In the ‘Blue’ corner, we have a flight of four F-35A JSFs, each armed with four AIM-120D Beyond Visual Range (BVR) missiles and the 25 mm GD ATP GAU-22/A cannon. No additional weapons or fuel are carried, because these would compromise the JSFs' “low observability” to X-Band radar. In the ‘Red’ corner, we have a flight of four Su-35S, each armed with four RVV-SD Active Radar Seeker BVR Missiles, four RVV-SD Infra-Red (IR) Seeker BVR missiles, two RVV-MD Within Visual Range (WVR) missiles, the 30mm GSh-301 cannon, KNIRTI SAP-518 jammers on the wingtips and a 6,000 litre conformal tank between the engines. Each aircraft has the full range of sensors and countermeasures.
Airframe Agility: Once warned of a launch, the defending aircraft can sometimes defeat the attack by rapidly turning away to force the missile into a tail-chase.Antenna Coverage: AESA radars like the JSF APG-81 working from a fixed back-plate cover a cone of about 120 degrees. The Su-35S has an ESA radar working from a gimballed ‘swash-plate’ that covers about 240 degrees around the nose, and there is a second radar in the ‘stinger’ albeit with less capability, to cover the remainder of the sphere. If the Su-35S and the JSF fire a BVR missile at the same time and at maximum range, the Su-35S can turn away to about 120 degrees off the line joining the two aircraft, while the JSF is constrained to about 60 degrees. This runs the JSF into the Su-35S’s missile, while the Su-35S is running away from the JSF’s missile. The result could be an RVV-SD hit and an AIM-120 miss. Points to the Su-35S on this aspect.Mach on Egress / Fuel Reserves for Afterburner: This is an extension of the antenna coverage capability, as the Su-35S can accelerate away from the incoming missile, forcing it to drop-short. The JSF does not have this performance and is assessed as inferior.
Destroy:Missile Seeker Diversity: At terminal phases of an engagement, there may be several missiles in the vicinity, with aircraft manoeuvring to defeat the attack. An incoming missile with an IR seeker may be presented with the ‘rear end’ of a JSF and track for a kill. This opportunity is not available to the JSF attacking the Su-35S, as its limited missile carriage does not include BVR missiles with IR seekers.Missile Agility: This is the ‘flip side’ of aircraft agility. The R-77 has the famous ‘potato masher’ lattice-tail control surfaces, that while increasing drag over conventional surfaces, also give greater terminal manoeuvring capability. So, the Su-35S BVR weapons can out-turn the F-35’s weapons.Warhead Lethality: This is a mix of warhead destructive power and the vulnerability of the target airframe. The AIM-120D has an 18 Kg, fragmentation warhead, and the Su-35S widely spaced armoured engines, armoured sections of the airframe and redundancy of system. The R-77 missiles have 30 kg expanding-rod warheads to destroy the single-engine JSF, from which critical systems like fire suppression have been removed to reduce weight and cost. The Su-35S is assessed as superior.WVR Missiles: This is as simple as ‘the Su-35S carries WVR missiles, the JSF does not’ (in this example). The JSF can carry WVR missiles, but they are an external mount, impairing radar signatures.Guns Lethality: Bigger is better. 30 mm rounds have more explosive power than 25 mm rounds. Again, the airframe vulnerability is an issue and a single 30 mm hit to the JSF’s single engine could bring it down.
At the end of the kill-chain, it seems, prima facie, that the Su-35S has all the ‘right stuff’ for air combat, while the F-35 JSF does not. This should come as no surprise, because the design brief for the JSF was that the F-22A would ‘sanitise’ airspace and deliver air dominance, making it safe for the Joint STRIKE Fighter to deliver follow-up strike capabilities.
Now that the F-22A Raptor program is being terminated with insufficient aircraft to deliver air dominance, this role is now being assigned to the F-35 JSF.
Given the intent of the OSD to employ the F-35 Joint Strike fighter as an air dominance fighter, the fundamental and unanswered question is: