Part 1
- Designing an aircraft
is a major task. World wide in big companies employs 100s of engineers to
design aircraft and its components. Nevertheless with so many years in
aircraft designing, the industry has a road map of how to go about
designing an aircraft.
2. A typical design of aircraft goes through following steps :-
-Studying user requirements
-Literature and historical
survey of available aircrafts of the class and available technology
-Feasibility and
constraints
-Preliminary Design
-Weight calculations
-Drag Polar Calculations
-Weight estimations
-Selection of optimum wing
loading
-CG Calculations
-AC Stability Calculations
- Let us take a small
exercise of designing a 40, 000 Kg Freighter which can take upto around
400 passengers. Its range should be around 6500 – 7000 Km and endurance to
be about 8 hrs. Mach no to be at 0.8 – 0.8.
- A Survey of following
aircrafts was undertaken.
-
Mc
Donnell Douglas DC – 10 Transport.
-
Aribus
A 320.
-
Ilyushin
76.
-
Lockheed
L- 100 Series.
-
Ilyushin
86II.
-
Boeing
707.
- As an example the
survey of Mc Donnell DC 10 is given here, then when all the aircrafts of
the same class were studied, ‘Ratios were obtained from the collected
data’ so that general indications of fuel weight, basic empty weight, wing
loading, powerplant could be arrived at.
The ratios of various parameters such
as fuel weight, basic empty weight, wing loading, power plant is given here.
RATIOS OBTAINED FROM
COLLECTED DATA
