Page 63 - Aeronautical Engineer Data Book

50 Aeronautical Engineer’s Data Book
3.3 Densities of liquids at 0°C
See Table 3.3.
Table 3.3 Densities of liquids at 0°C

Liquid kg/m 3 lb/ft 3 Specific gravity
Water 1000 62.43 1
Sea water 1025 63.99 1.025
Jet fuel JP 1 800 49.9 0.8
JP 3 775 48.4 0.775
JP 4 785 49 0.785
JP 5 817 51 0.817
Kerosine 820 51.2 0.82
Alcohol 801 50 0.801
Gasoline (petrol) 720 44.9 0.72
Benzine 899 56.12 0.899
Oil 890 55.56 0.89

3.4 Notation: aerodynamics and fluid
mechanics
See Table 3.4.
Table 3.4 Notation: aerodynamics and fluid mechanics
The complexity of aeronautics means that symbols may
have several meanings, depending on the context in
which they are used.
a Lift curve slope. Acceleration or deceleration.
Local speed of sound. Radius of vortex core.
a' Inertial or absolute acceleration.
Speed of sound at sea level. Tailplane zero
a 0
incidence lift coefficient.
Tailplane lift curve slope.
a 1
Elevator lift curve slope.
a 2
Elevator tab lift curve slope.
a 3
a ∞ Lift curve slope of an infinite span wing.
Local lift curve slope at spanwise co-ordinate h.
a h
Local lift curve slope at spanwise co-ordinate y.
a y
ac Aerodynamic centre.
A Aspect ratio. Moment of inertia. Area.
A State matrix.
AF Activity factor of propeller.
b Total wing-span (= 2s). Hinge moment
coefficient slope. Rotational factor in propeller
theory. General width.
Elevator hinge moment derivative with respect
b 1
to T .
Elevator hinge moment derivative with respect to .
b 2