Aerodynamics of gliding flight in a falcon and other birds
Abstract
ABSTRACT A live laggar falcon (Falco jugger) glided in a wind tunnel at speeds between 6·6 and 15·9 m./sec. The bird had a maximum lift to drag ratio (L/D) of 10 at a speed of 12·5 m./sec. As the falcon increased its air speed at a given glide angle, it reduced its wing span, wing area and lift coefficient. A model aircraft with about the same wingspan as the falcon had a maximum L/D value of 10. Published measurements of the aerodynamic characteristics of gliding birds are summarized by presenting them in a diagram showing air speed, sinking speed and L/D values. Data for a high-performance sailplane are included. The soaring birds had maximum L/D values near 10, or about one quarter that of the sailplane. The birds glided more slowly than the sailplane and had about the same sinking speed. The ‘equivalent parasite area’ method used by aircraft designers to estimate parasite drag was modified for use with gliding birds, and empirical data are presented to provide a means of predicting the gliding performance of a bird in the absence of wind-tunnel tests. The birds in this study had conventional values for parasite drag. Technical errors seem responsible for published claims of unusually low parasite drag values in a vulture. The falcon adjusted its wing span in flight to achieve nearly the maximum possible L/D value over its range of gliding speeds. The maximum terminal speed of the falcon in a vertical dive is estimated to be 100 m./sec.
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During a dive, peregrines can reach velocities of more than 320 km/h.
“During a dive peregrines can reach velocities of more than 320 km h−1.”
From Diving-Flight Aerodynamics of a Peregrine Falcon (Falco peregrinus) (2014) · cites this paper as [3]
Cites
Modern Developments in Fluid Dynamics
Milne-Thomson, L. M., & Goldstein, S. (1939) · The Mathematical Gazette · doi:10.2307/3607555 · Cited by 1,646 · see citing works
Rae, W. H., & Pope, A. (1966) · Infoscience (Ecole Polytechnique Fédérale de Lausanne) · Cited by 1,338 · see citing works
Applied hydro- and aeromechanics
Tietjens, O. K. G., & Prandtl, L. (1934) · Medical Entomology and Zoology · Cited by 736 · see citing works
Airfoil section characteristics as affected by variations of the Reynolds number
Jacobs, E. N., & Sherman, A. (1939) · Cited by 346 · see citing works
Mises, R. V. (1959) · Medical Entomology and Zoology · Cited by 290 · see citing works
Airplane Performance, Stability and Control
Perkins, C. D., & Hage, R. E. (1991) · Medical Entomology and Zoology · Cited by 273 · see citing works
Airplane performance, stability and control
Berkowitz, S. M. (1950) · Journal of the Franklin Institute · doi:10.1016/0016-0032(50)90415-7 · Cited by 269 · see citing works
A Wind-Tunnel Study of Gliding Flight in the Pigeon Columba Livia
Pennycuick, C. J. (1968) · Journal of Experimental Biology · doi:10.1242/jeb.49.3.509 · Cited by 215 · see citing works
Modern Developments in Fluid Dynamics
Lunkenheimer, P. P. (1939) · Nature · doi:10.1038/144529a0 · Cited by 200 · see citing works
Gliding Flight of the Fulmar Petrel
Pennycuick, C. J. (1960) · Journal of Experimental Biology · doi:10.1242/jeb.37.2.330 · Cited by 57 · see citing works
Raspet, A. (1960) · Science · doi:10.1126/science.132.3421.191 · Cited by 43 · see citing works
North American Falconry and Hunting Hawks
McGahan, J., Beebe, F. L., & Webster, H. M. (1967) · Journal of Wildlife Management · doi:10.2307/3798384 · Cited by 32 · see citing works
Elements of practical aerodynamics
(1950) · Journal of the Franklin Institute · doi:10.1016/0016-0032(50)90301-2 · Cited by 28 · see citing works
Austin, O. L., & Jameson, W. (1960) · Bird-Banding · doi:10.2307/4510824 · Cited by 14 · see citing works
Performance measurements of a soaring bird
Raspet, A. (2017) · OSTIV Publications · Cited by 11 · see citing works
Wind Channel Experiments on a Pariah Kite
Page, W. L. L. (1923) · Journal of the Royal Aeronautical Society · doi:10.1017/s0368393100158237 · Cited by 7 · see citing works
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Gliding Flight: Speed and Acceleration of Ideal Falcons During Diving and Pull Out
Tucker, V. A. (1998) · Journal of Experimental Biology · doi:10.1242/jeb.201.3.403 · Cited by 95 · see citing works
Self-citationDiving-Flight Aerodynamics of a Peregrine Falcon (Falco peregrinus)
Ponitz, B., Schmitz, A., Fischer, D., Bleckmann, H., & Brücker, C. (2014) · PLoS ONE · doi:10.1371/journal.pone.0086506 · Cited by 77 · see citing works
Relationships between morphological parameters in birds with different flying habits
Viscor, G., & Fuster, J. F. (1987) · Comparative Biochemistry and Physiology Part A: Physiology · doi:10.1016/0300-9629(87)90118-6 · Cited by 60 · see citing works
Tucker, V. A. (1990) · Journal of Experimental Biology · doi:10.1242/jeb.149.1.449 · Cited by 54 · see citing works
Self-citationFlying ability of Archaeopteryx
YALDEN, D. W. (1971) · Nature · doi:10.1038/231127a0 · Cited by 26 · see citing works
Schmitz, A., Ponitz, B., Brücker, C., Schmitz, H., Herweg, J., & Bleckmann, H. (2015) · Journal of Morphology · doi:10.1002/jmor.20317 · Cited by 18 · see citing works
- Authors
- Tucker, V. A., & Parrott, G. C.
- Affiliations
- Duke University (US)
- Venue
- Journal of Experimental Biology
- Publisher
- The Company of Biologists
- Published
- 1970-04-01
- Volume
- 52
- Issue
- 2
- Pages
- 345-367
- ISSN
- 0022-0949 (ISSN-L)
- 1477-9145
- OpenAlex
- W1921571842
- Cited by
- 209
- References
- 16
- Citations by year
- 2026: 4 · 2025: 5 · 2024: 3 · 2023: 8 · 2022: 10 · 2021: 10 · 2020: 10 · 2019: 4 · 2018: 6 · 2017: 10 · 2016: 7 · 2015: 3 · 2014: 8 · 2013: 4 · 2012: 4
- FWCI
- 43.82
- Type
- journal article
- Language
- en
- Open access
- closed
- Locations
- Journal of Experimental Biology (publishedVersion)
- Topics
- Physical Sciences › Engineering › Aerospace Engineering › Biomimetic flight and propulsion mechanisms
- Physical Sciences › Engineering › Aerospace Engineering › Aerospace and Aviation Technology
- Physical Sciences › Engineering › Computational Mechanics › Fluid dynamics and aerodynamics studies
- Keywords
- gliding flight, falcons, lift-to-drag ratio, soaring birds, parasite drag, sinking velocity, bird flight aerodynamics
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