Greetings everyone. In this thread I want to discuss a problem that I think has become rampant throughout the WT community, including also several content creators: the perceived idea that the Gripen is a bad performing aircraft when compared to other 4th Gen fighters. I’m aware of the fact that the flight model in the dev server is not an accurate representation of the Gripen capabilities, as it currently allows the player to throw the nose around as if it was an RC plane, what I want to focus on instead is the incredulity that many people share when they see the Gripen outrate a Flanker, retain its energy past the first turn or give the F-16A a serious run for its money in a dogfight. This incredulity, which has already lead a lot of people into expecting or outright demanding severe nerfs for this jet’s maneuverability, seems to stem entirely from two key aspects of the Gripen design: its unremarkable thrust/weight ratio (from here on written as TWR) and its delta wing, which is commonly associated with a strong loss of speed in high-G turns.
First of all, while a high TWR is certainly a desirable quality in a fighter aircraft, especially when performing vertical maneuvers, it is nowhere near as important as the aerodynamic design in defining the flight characteristics of that aircraft; if this wasn’t true, the F-104 would be a better dogfighter than the F-5E and the Harrier would be as good as the F-16A in a ratefight. Let’s speak therefore of the Gripen aerodynamic design because, contrary to the popular belief… A DELTA WING DOES NOT AUTOMATICALLY EQUATE A BAD ENERGY RETENTION. Expecting the Gripen to beheave like a MIG-21 because it has a delta wing is like expecting the F-14 to beheave like a Tornado because it has a variable sweep wing.
Let’s understand the problem first: delta wings are generally characterised by high sweep angles and low aspect ratios. While this configuration achieves a very low wave drag, granting the aircraft a smooth transition through the transonic regime and the ability to achieve a high Mach number even without huge amounts of thrust, it introduces two major issues: a high lift-induced drag coefficient (CDi) and a low lift curve slope. These are the sources of the severe energy loss that plagued older delta fighters in high-G turns: to generate the lift necessary to perform a certain G turn, a delta winged aircraft typically requires a higher than average angle of attack which, coupled with the high CDi, means a lot of lift-induced drag.
But if that’s the case, then why do all european fighters have delta wings?
BECAUSE THIS PROBLEM CAN BE FIXED, using an unstable canard configuration with fly-by-wire controls. Relaxed stability (ie placing the center of gravity behind the center of lift) allows to replace the intrinsic pitch-down moment of a stable aircraft with an intrinsic pitch-up moment, as well as improving handling and bringing trim drag to almost zero. Furthermore, unlike traditional tail controls, canards in a turn exert an upward force that sums to lift rather than a downward force, thus decreasing wing loading rather than increasing it. These factors combined dramatically reduce the amount of lift required to perform a certain G-turn, therefore the necessary associated AOA, therefore also the drag experienced by the aircraft in that turn. The Gripen canards are close-coupled, meaning that their tip vortices are exploited to energize the airflow over the wings, improving lift-generation and augmenting the high-alpha performance of the wing itself. Its small and narrow airframe, paired with its highly swept and short-spanned wings, also gives it possibly the lowest drag in straight flight out of any 4th Gen fighter (just think at the fact that it achieves a higher top speed than the F-18 with half the thrust), which compensates to a degree for its unremarkable engine power when it comes to acceleration and climb rate: while there is no such thing as too much thrust, if drag is very low, you don’t need a lot of thrust to overcome it.
Unfortunately, the EM Diagrams of the Gripen are still classified but we can still get an idea of its performance from videos and pilot accounts. For example, have a look at this:
At 5:35, we can appreciate an uninterrupted 9G turn for 10 seconds, something unthinkable for older delta fighters and even for some of the Teen Series aircrafts. Then we have the account of Mikael Grev, a Gripen pilot with DACT experience against the norwegian and danish F-16s (MLU variant) and against the finnish F-18s (C variant) who also flew on the F-16. While pilot accounts are not necessarily unbiased, as an experienced pilot can often defeat a superior aircraft (Sharkey Ward famously scored several F-15 kills in his Sea Harrier), they still remain in my opinion the best and most trustworthy sources when EM Diagrams are not available. Mikael Grev released one interview to the channel Aircraft Interview:
and one to the site Hushkit
Flying & Fighting in the Gripen: Interview with a Swedish Air Force pilot | Hush-Kit.
I suggest you read/listen to both, but the short story is that he found the Gripen to perform very similar to the F-16 but with better handling qualities. By contrast, he found the F-18 to be a more dangerous opponent due to its ability to pull a lot of AOA, but also noted that the Gripen retained energy better in a turn.
Considering all I’ve said so far, plus the fact that in War Thunder balancing between factions also plays a role and that the MIG-29G, all the F-15s and especially the SU-27/J-11 Flanker all have much better weapon loadouts at the moment, it’s not therefore unreasonable to see the Gripen closely tied with the F-16A for the title of best dogfighter at top tier, although an increase in BR to 12.3 might be necessary. Thanks to all who took their time to read this, I hope it gave you a better insight about the Gripen and delta winged aircrafts in general.
As per the sources:
Fighters and Fighter Bombers (by Octavio Diez)
A Handbook of Fighter Aircrafts (by Francis Crosby)
World Aircraft Information Files
The Hushkit Book of Warplanes
P.S: I am aware of this document, however note that in this page ITR and STR are provided without any indication of altitude, air temperature, weight configuration and engine power (MIL or MAX AB). Without these reference data, ITR and STR are not that useful. Upon a more detailed look theese data are from a document that not only doesn’t show anything meaningful for the reasons mentioned above, but how could It since It makes a comparison with a Plane that never existed, the AT2000… All that further proves the inconclusiveness of the document.
Here Is the document:
Thanks to @Fluffy_Bucketles for pointing It out @Shoot_Harder for providing me the source about the two G-limiters present in the Gripen, the soft One at 9G and the hard One at 12G. Here Is the timestamp:
