Table 2.

Wingbeat kinematics variables (mean ± s.d.) for flycatcher no. 1 and no. 3 flying at U_∞ = 2, 4 and 7 m s⁻¹. The variables are flap frequency f; downstroke ratio R_ds; span ratio SR; mean effective wing speed during the downstroke of wrist and wingtip; effective Reynolds number Re_eff of wrist and wingtip; downstroke-based Strouhal number St_ds of wrist and wingtip; mean angle-of-attack (), maximum angle-of-attack (α_max) and angle-of-attack amplitude (A_α) of both wing and tail; mean tail spread angle ; maximum tail spread angle ϕ_max; normalized vertical body movement amplitude .

U∞ (m s−1)	2	4	7
f (s−1)	12.6 ± 0.8	12.0 ± 0.4	12.1 ± 0.7
Rds (–)	0.45	0.42	0.42
SR (–)	0.087	0.092	0.093
1 (m s−1)	2.42	4.28	7.20
1 (m s−1)	5.7	6.7	9.0
Reeff wrist (–)a	6.9×103	12.3×103	20.7×103
Reeff tip (–)a	16.3×103	19.1×103	25.7×103
Stds wrist (–)a	0.11	0.06	0.04
Stds tip (–)a	0.42	0.31	0.23
(°)	34.3 ± 3.8	17.3 ± 2.3	6.0 ± 2.7
αwing max (°)	40.9 ± 3.0	22.3 ± 1.3	10.6 ± 2.5
Aα wing (°)	46.1	25.2	12.9
(°)	36.6 ± 7.9	19.6 ± 5.1	6.2 ± 7.1
αtail max (°)	39.0 ± 4.4	26.4 ± 4.2	12.6 ± 4.2
Aα tail (°)	25.3	17.5	13.1
(°)	33.0 ± 10.6	32.5 ± 8.9	28.1 ± 11.2
ϕmax (°)	42.9 ± 12.6	40.2 ± 7.9	33.9 ± 18.9
(–)	0.063	0.068	0.082

^aBased on the downstroke part of the wingbeat, as it is assumed that the upstroke is inactive.