Supercruise
Supercruise is sustained supersonic flight of a supersonic aircraft without using afterburner. Many supersonic military aircraft are not capable of supercruise and can maintain Mach 1+ flight only in short bursts with afterburners. Aircraft such as the SR-71 Blackbird are designed to cruise at supersonic speed with afterburners enabled.
Some fighter jets are capable of supercruise but only at high altitudes and in a clean configuration, so the term may imply "a significant increase in effective combat speed with a full weapons load over existing types".<ref name="defenceaviation_1">Template:Cite web</ref> One of the pre-eminent military examples of supercruise is the F-22 Raptor, for which supercruise was defined as "the ability to cruise at speeds of one and a half times the speed of sound or greater without the use of afterburner for extended periods in combat configuration."<ref name="fas1">Template:Cite web</ref>
One of the best-known examples of an aircraft capable of supercruise, and the only notable non-military example, was the Concorde. Due to its long service as a commercial airliner, the Concorde holds the record for the most time spent supersonic; more than all other western aircraft combined.<ref name="janes">Template:Cite web</ref>
History
A few early supersonic aircraft attained speeds just beyond the speed of sound without using afterburning.
On 3Template:NbspAugust 1954, a Gerfaut research aircraft powered by an SNECMA Atar 101D2A engine exceeded MachTemplate:Nbsp1 in level flight without using afterburning.Template:Sfn<ref name="flightglobal">Template:Cite web</ref>
The first production aircraft to exceed MachTemplate:Nbsp1 in level flight without afterburning was the Lockheed F-104 Starfighter after its J65 engine was replaced with a J79. The maximum speed without afterburning was MachTemplate:Nbsp1.05.Template:Sfn
The P.1 prototype of the English Electric Lightning, powered by non-afterburning Armstrong Siddeley Sapphire engines, exceeded MachTemplate:Nbsp1 on 11Template:NbspAugust 1954. A week previously, on 4Template:NbspAugust, the P.1, WG760 flown by Roland Beamont on its maiden flight, had unknowingly exceeded MachTemplate:Nbsp1 in a climb.<ref name="flightglobal2">Template:Cite web</ref> During development testing at English Electric it was established that the Lightning had a stabilized speed capability in level flight, without afterburning, of about MachTemplate:Nbsp1.2 and for the T.4 (2-seat trainer) 1.08.Template:Sfn Flying just above the speed of sound without using afterburning, although done by the contractor as part of some flight trials does not appear to have been relevant to the operational capability of the aircraft. Service trials established intercept profiles for subsonic and supersonic targets at different altitudes with subsonic cruising at a maximum of MachTemplate:Nbsp0.95 with all supersonic speeds beyond subsonic cruise attained with afterburning.Template:Sfn
All the Fairey Delta 2 initial supersonic test flying to MachTemplate:Nbsp1.1 was done without afterburning. Selecting the afterburner, which initially only had a maximum selection with no intermediate positions, would have caused an uncontrollable rapid acceleration to potentially hazardous speeds; i.e., too far beyond previously established flutter-free speeds.Template:Sfn
Only the supersonic transports (SST), Concorde, and the second version of the Tu-144 (the Tu-144D) spent most of their time cruising at their design speeds without needing afterburning. Afterburning was added to Concorde for take-off to cope with weight increases that came after the initial design. It was also used to accelerate through the high-drag transonic speed range, not because the extra thrust was required, but because it was available and improved the operating economics. The redesigned Tu-144D used engines with no afterburners which, together with other improvements, increased the full payload range from Template:Cvt (Concorde's operational range was Template:Cvt).Template:Sfn
Military use
The United States Air Force set supercruise as a core requirement for the Advanced Tactical Fighter program,<ref name="rand_1">Template:Cite web</ref> which resulted in the F-22 Raptor. The F-22 Raptor's supercruise capabilities are touted as a major performance advantage over other fighters, with supercruise being demonstrated exceeding MachTemplate:Nbsp1.5.<ref name="f22-1">Template:Cite web</ref><ref name="fas1" /> Supercruise capability provides advantages for stealth aircraft because an afterburner plume reflects radar signals and creates a significant infrared signature.<ref name="fighter-planes">Template:Cite web</ref> Virtually all fighters prior to the F-22 cruise at MachTemplate:Nbsp0.8–0.9 while carrying a normal weapons load.<ref name="defenceaviation_1" />
There are a few engines in production that are designed to facilitate tactically significant supercruise:
- The Pratt & Whitney PW1120 was used on the IAI Super Phantom 2000 that had supercruise capability.<ref name="Odyssey p289-90">Spick 1985, pp. 289-90.</ref><ref>Template:Cite web</ref>
- The two Pratt & Whitney F119 that power the F-22 Raptor make it the most capable supercruise-capable fighter aircraft in service. The F-22 Raptor can supercruise above Mach 1.5 without external stores.<ref name="af.mil">General Jumper qualifies in F/A-22 Raptor, af.mil, January 13, 2005</ref><ref>Template:Cite web</ref><ref name="f22-1" />
- The EJ200 engine built by EuroJet Turbo GmbH mounted in the Eurofighter Typhoon. It is capable of supercruising at Mach 1.5 with an air superiority missile load.<ref name="ef1" /> Typhoon pilots have stated that Mach 1.3 is attainable in combat configuration with external stores.<ref name="fighter-planes2">Template:Cite web</ref>
- The General Electric F414G in the JAS 39 Gripen NG is designed for supercruise and has achieved Mach 1.2,<ref name="gripen1">Template:Cite web</ref> or Mach 1.1 with an air to air missile load.<ref name="gripen2">Template:Cite web</ref>
- The two Snecma M88s that power the Dassault Rafale enable the Rafale to supercruise with four missiles and a belly drop tank.<ref name="rafale1" />
Independently, Russia is working on izdeliye 30 (after AL-31F and AL-41F derivatives modifications, like izdeliye 117S turbofan) and RD-33MKRU Morskaja Osa; an all-new AL-41 engine with a complete redesign is underway to add supercruise ability to the Sukhoi Su-57. This has yet to bear fruit, but the stop-gap 117S engine, produced by this program, may achieve the supercruise goal already. While testing a Su-35BM fighter equipped with these engines, it managed to accelerate past Mach 1 without using the afterburner, suggesting that it had supercruise capability. It has yet to be seen whether this will be possible with a combat load.<ref name="lenta">Template:Cite web</ref>
Aircraft with supercruise ability
| Aircraft | Supercruise speed | Production Year | Service status |
|---|---|---|---|
| Sukhoi Su-57<ref>Template:Citation—Adresses the display of the SU57 production model fitted with new Saturn AL-41F1 (117) engines allowing Supercruise ability at Mach 1.3.</ref> | Mach 1.30 | 2020 | In service |
| Dassault Rafale<ref name="rafale1" /> | Mach 1.40<ref>Template:Cite web</ref> | 1986 | In service |
| Eurofighter Typhoon<ref name="ef1" /> | Mach 1.50 | 1994 | In service |
| Saab JAS-39E Gripen<ref name="gripen1" /> | Mach 1.10<ref name="gripen2" /> | 2019<ref>Template:Cite web</ref> | In service |
| General Dynamics F-16XL<ref>Template:Harvnb: "F-16XL-2 was also able to demonstrate limited supercruise performance by maintaining Mach 1.1 at an altitude of 20,000 feet in full military power without resorting to the use of afterburner."</ref> | Mach 1.10 | 1982 | Retired (prototype) |
| Lockheed Martin F-22 Raptor<ref name="f22-1" /><ref name="fas1" /> | Mach 1.76 | 1996 | In service |
| Lockheed YF-22<ref name="yf-22-23">Template:Cite web</ref> | Mach 1.58Template:Sfn | 1989 | Retired (prototype) |
| Northrop YF-23<ref name="yf-22-23"/> | Mach 1.72<ref name="test_pilot_interview">Template:Cite AV media</ref> | 1989 | Retired (prototype) |
| Concorde<ref>Template:Citation—describes full cycle of Concorde's engine from takeoff to touchdown, including the turning off of reheat to begin supercruise at Mach 1.7.</ref> | Mach 2.02Template:Sfn | 1965 | Retired |
| EWR VJ 101 | Mach 1.04<ref>Template:Cite web</ref> | 1962 | Retired (prototype) |
| Mikoyan Project 1.44 | Mach 1.50<ref>Template:Cite web</ref> | 1999 | Retired (prototype) |
| Chengdu J-20 | N/A<ref>Template:Cite web</ref><ref>Template:Cite web</ref> | 2009 | In service |