Table 4.

Muscle-mass specific aerodynamic powers – wing results

Cycle powers (weight support 74.5±7.7%)
For both wings For a single wing or pectoralis
Aerodynamic power (W)Body-mass specific power (W kg-1)Muscle-mass specific power (W kg-1)Peak force on a wing (N)Peak force on a pectoralis (N)Peak pectoralis stress (kNm2)
Method for power calculation
   Direct measurements: mean kinematics and 5-site pressure map applied to 3 pigeons25.6±3.851.2±5.1272.7±26.75.759.074.1
   Induced power6.5914.379.5
  • Induced power is calculated following Pennycuick (1989) with the mean wing span and mass from Table 3 and flight speed from Table 2. The induced power factor k is taken as its default value of 1.2. Muscle-mass specific powers are calculated assuming that the pectoralis dominates downstroke power and constitutes 18% of body mass. Muscle force and stress are calculated using the wing geometry (specifically the shoulder to delto-pectoral crest distance and the cross section of the pectoralis) from pigeons used in other studies (Dial and Biewener, 1993; Biewener et al. 1998; Soman et al., 2005) scaled to the mean body mass of the wild-type pigeons used here, for which a value of 7.385 cm2 was used for the physiological cross-sectional area of the muscle. These values, therefore, should be considered approximate.