How a bird works Colin Pennycuick

University of Bristol

Elbow

Wrist

Splayed tips

Primary

feathers

Secondary

feathers

Tail

Undercarriage

(water, land)

Engine

Navigation

Speed Span Area Beta AR Cl

m/s m m2

8.6 0.67 0.063 1 6 1.3 60,000

12.4 0.57 0.85

22.1 0.25 0.0385 0.37 1.3 0.25 300,000

Re

Energy height dep 381 249

Energy height arr 245 70

Energy height lost 136 179

L/D 11.2 7.8

White-fronted Goose Cessna 182

Goose

Cessna 182

BIRD

Multiple spars

BAT

Segmented spar

PTEROSAUR

Single spar