Gripen E drag characteristics
Executive summary
The Gripen E’s drag characteristics are shaped by a canard–delta planform, a relatively clean airframe and a higher-thrust F414G engine, producing low-to-moderate drag in combat configurations but notable penalties when externally loaded with tanks or weapons; public technical sources document vortex-aided lift at modest angles of attack, a peak L/D near 5°, and operational caveats about supersonic performance when fully tanked [1] [2] [3] [4].
1. Aerodynamic architecture: canards, delta wing and net effect on drag
The Gripen family’s hallmark canard-plus-delta layout gives the aircraft distinctive vortex lift and control traits: the canards contribute a positive lift force across much of the flight envelope while the delta wing supplies generous lift, a combination that helps trim and maneuverability but changes how induced and profile drag develop with angle of attack and load [1] [5]. Academic CFD and wind‑tunnel work on Gripen-like, canard–delta configurations finds strong vortex generation from sharp leading edges that raises lift at higher angles but also alters pressure distributions that affect drag; those studies show a trade‑off where vortex lift delays separation and raises maximum CL but can increase form and vortex-induced drag in certain regimes [2] [6].
2. Performance numbers public and measured: L/D, CL, and stall behavior
Published CFD/wind‑tunnel research on a Gripen C–like model reports a peak lift‑to‑drag ratio at roughly 5° angle of attack and a maximum CL around 1.43, with stall occurring near 40° AoA on the model tested—figures that indicate good low‑AoA efficiency but also that high‑AoA vortex phenomena dominate beyond that point [2] [6]. That research is model‑based rather than full‑scale flight test data, so it illuminates aerodynamic trends (lift peak, vortex influence) rather than supplying definitive full‑vehicle drag polars for the production Gripen E [2] [6].
3. Clean‑airframe vs loaded‑airframe: wave drag and external stores
Operational reporting and comparative analysis emphasize that the Gripen E flies clean with relatively low external drag, but drag grows significantly when the aircraft carries external tanks or stores; in practice pilots “drop their bags” (external tanks) to regain agility and reduce drag penalties, and independent commentary even asserts the Gripen E can lose supersonic capability with three external tanks fitted [4]. The broader aerodynamic point is standard: slender internalized stores and a clean planform minimize wave and pressure drag at transonic/supersonic speeds, while pylons, tanks and missiles substantially increase wave drag and reduce maximum attainable Mach [4] [7].
4. Design changes on E variant that influence drag trends
The Gripen E introduces dimensional and internal changes—longer fuselage aft of the wing, integrated fuel tanks and a more powerful GE F414G engine—which affect center of gravity, internal volume and engine‑airframe interactions; Saab and industry reporting link those changes to better range, payload and handling, but publicly available sources do not publish a full drag polar for the E, so the net quantified drag change versus earlier variants is described qualitatively rather than numerically [8] [3] [9]. Saab’s marketing emphasizes sensor fusion and networked tactics rather than direct drag figures, reflecting a focus on mission systems more than raw aerodynamic coefficients [9] [10].
5. Conflicting claims, testing limits and what remains unknown
Industry and enthusiast commentary diverge on practical drag consequences: manufacturer material highlights agility and efficient systems integration [9], academic CFD shows vortex-assisted lift and a best L/D at low AoA but is model‑based [2] [6], and independent analysts caution that external tanks can blunt supersonic performance [4]. Crucially, none of the supplied sources provides a comprehensive, published drag polar or fully instrumented flight‑test Cd/Cd0 tables for the production Gripen E, so precise total‑drag vs speed numbers and in‑service fuel‑burn impacts cannot be asserted from these sources [2] [3] [8].