DA40 General Description 
DA40 Systems word doc

AIRFRAME
 The Fuselage is made out of Glass Fiber Reinforced Plastic (GFRP) and is semi monocoque molded construction.  The fire protection on the firewall is made of special fire-resistant matting and that covers the engine side by stainless steel cladding.  The two main bulkheads are GFRP and Carbon Fiber Reinforced Plastic (CFRP). 

The wings have a front and rear spar; each wing has a top and bottom shell – a ‘fail safe’ concept.  The wings as well as the aileron and flaps, are made of GFRP/CFRP, and are principally of sandwich construction. Each wing holds an aluminum fuel tank.

 The Empennage of the Diamond has a ‘T’ tail made of GFRP semi monocoque construction. Both the stabilizers have twin spars and a skin with no sandwich.  Rudder and elevator are of sandwich construction.

ENGINE
Lycoming IO-360-M1A - IO stands for Injected & Opposed

     Four cylinder - 180 H.P. at 2700 RPM
Horizontally opposed
Air cooled
Normally Aspirated
Direct drive

PROPELLER
The Diamond is equipped with a MT-Propeller which has a two-bladed, controllable pitch, constant speed, full feathering(pitch range 10.5° - 30°) , metal propellers.

Controllable Pitch
Controllable pitch is the ability to control engine RPM by varying the pitch of the propeller blades. When the blue propeller control handle is moved forward, oil pressure, regulated by a propeller governor, drives a piston, which moves the blades to a low pitch-high RPM (unfeathered position). When the blue propeller control handle is moved aft, oil pressure is increased by the propeller governor. Keep in mind this is the exact opposite of a multi-engine setup. Loss of oil pressure in a twin would cause the propeller to feather. 

LANDING GEAR

The landing gear consists of a main landing gear of sprung steel struts, and a

free-castering nose wheel which is sprung by an elastomer package.

BRAKES
The Diamond has hydraulically operating disk brakes that act on the wheels of the main landing gear. The wheel

brakes are individually operated by means of toe pedals. The brakes are the main system to control the Diamond while taxing.

PARKING BRAKES
The lever is located on the small center console under the instrument panel, and is in the upper position when the brakes are released.  To operate the parking brake pull the lever downwards until it catches. Brake pressure is built up by multiple operation of the toe brake pedals, and is maintained until the parking brake is released. To release, the

lever is pushed upwards.

FLAPS
The Diamond is equipped with plain flaps and closer to the fuselage are split flaps.  The flaps are operated by means of an electric 3-position flap selector switch on the instrument panel. Flap settings are Cruise (UP), Take-off (T/O), and Landing (LDG).

VACUUM PUMP
There is none on CSA's airplanes.  All electric...

PITOT STATIC SYSTEM
The Pitot-static system pressure is gathered all on one probe.  The probe is located under the left wing.  The ram air pressure is measured on the leading edge of the Pitot probe and the static pressure is measured on the lower and rear edges of the Pitot probe. The Pitot probe is electrically heated to prevent icing.

FUEL SYSTEM
The Diamond, which uses 100 low lead avgas (blue), is equipped with two 20.6 gallon tanks. The amount of total unusable fuel is .5 gallons per tank. Therefore there is a total of 41.2 gallons and only 40.2 gallons are usable. 


The fuel quantity indicator in the Diamond only shows up to 17 gallons in each tank.  Above this the total quantity in the tanks will be show until the fuel level goes below 17 in either tank. Each tank is has two vents. One vent acts as a capillary, both to equalize the air pressure, and to provide a safety factor in the event of a failure of the other vent. The second vent is a check valve, to allow air to enter the tank, but prevent flow to the outside.

Normally fuel is supplied to the engine through an engine-driven fuel pump. An electric fuel pump serves as a back-up feature and is used for engine start, takeoff, landing, and fuel selector changes.

ELECTRIC SYSTEM
The Diamond is equipped with a 28 volt DC electrical system which utilizes push-pull type circuit breakers: a 24 Volt, 11 amp hour battery ; and a 70 amp engine driven alternator with a voltage regulator and over voltage protection.

The airplane has four buses - a main bus and an avionics bus.  The third and four buses are the essential bus and the avionics essential bus, which are used in the event of an alternator failure and will only power the items that are absolutely needed for flight.

HEATER
An opening at the front right of the engine cowling admits ram air to the heater shroud and then the air is ducted to the heater shut-offs on the right and left side of the firewall. When the shut-off's are opened the heated air then enters the heat ducts and into the cabin. 

Resources

Information from the DA-40 Flight Manual (http://propwash.yolasite.com/resources/DA40%20Flight%20Manual.pdf) and General Description of the Airplane (http://propwash.yolasite.com/resources/DA40%20General%20Description.pdf)