16-02-2010, 08:00 PM
MECHANICAL SYSTEMS OF CONCORDE
After the World War II, Great Britain realized the necessity for faster civil planes and created the De Havilland D.H. 106 Comet, the first commercial plane with jet engines. During the 50's a committee was formed involving representatives from airlines, aircraft industries, engine industries and government employees to discuss an advanced design.
There were 3 possible innovative designs that could be followed.
The first was a plane with a very strange wing, -M shaped, with max speed 1.2 Mach.
The second design was the one that was similar with the final Concorde, with similar wing but with max speed 1.8 Mach.
The third one was chosen from the Americans and was for a huge plane with max speed 3 Mach.
The engines used afterburners, which are necessary for the plane to obtain supersonic speed.
An agreement was signed between the Britain and france for developing the plane.
The Olympus Mk 593B engine was used .
The aircraft used very complicated systems that were not used before.
France was constructing the 60% of the fuselage and wings, because Britain provided the engines.
When put into service The Concorde became very expensive to use with increasing oil prices . The end of Concorde era was just a few years back . The advance in aeronautics that it brought was enormous although its service life was short .
Maximum Operating Cruise Speed -Mach 2.04 (around 1350MPH)
Maximum Permissible Range- 4500 Miles
Average Take-off speed -250MPH
Average Landing speed -185MPH
Maximum operating altitude -60,000Ft
Maximum Oil temp for start and takeoff- 125 Degrees Celcius
Maximum Oil temp Continuous operation- 190 Degrees Celcius
Max Weight Without Fuel (Zero fuel weight -(92,080 kgs)
Max Payload - (13,380 kgs)
Max Take Off Weight - (185,000 kgs)
Engine Model : Olympus 593 Mrk610 turbojet
Engine Manufacturer : Rolls-Royce/SNECMA
Number fitted : Four
Maximum thrust produced at take off, per engine -38,050 lbs (170 KN) (with afterburner reheat in operation)
Maximum thrust produced during supersonic cruse, per engine -10,000 lbs
Reheat contribution to performance- 20% at full thrust during take-off
Fuel Type- A1 Jet fuel
Fuel Consumption (at Idle Power) -1100 kgs/hr .
Fuel Consumption (at Full Power) -10500 kgs/hr .
Fuel Consumption (at Full Re-heated power)- 22500 kgs/hr .
Roll-Royce provided the development of the Olympus engines while SNECMA developed the exhaust and reheat system. A total of 38,050Lbs thrust were available.
The Olympus engines are 2 spool engines. The inner shaft revolves within the outer shaft. The engine consists of 14 compressor stages, 7 on each shaft, driven by their respective turbine systems. At supersonic speeds when the air approaches the combustion chamber is is very hot due to the high level of compression of 80:1.
To protect the later compression stages the last 4 stages are constructed of a nickel-based alloy .The RPM of the engine's outer shaft is controlled by the amount of fuel being burnt. By varying the surface area of the primary nozzle, the inner shaft RPM can be controlled relative to the outer shaft RPM.
Concorde is the only civil airliner in service with a 'military style' afterburner system installed to produce more power at key stages of the flight. This reheat system, injects fuel into the exhaust, and provides 6,000Lb of the total available thrust per engine at take off. This is used on take off and is what is mainly responsible for the additional noise that Concorde makes. The reheats are turned off shortly after take off .
The Aircraft has an electrically controlled throttle system that is used to control the power delivered from the engines .The computer applies the power to the engines in a correct and controlled manner.
The engines also have ratings where they can be selected to different power or rating settings for different parts of the flight. eg take off or cruise. A contingency setting is available for use during engine failure and more power that normal is required from the remaining engines
AIRFLOWS AND INTAKES
To further improve engine system performance, the air flow through the engine area is changed at different speeds via a variable geometry intake control system .
The air intake ramp assemblies main job is to slow down the air being received at the engine face to subsonic speeds before it then enters the engines. At supersonic speeds the engine would be unstable if the air being feed to it was also at a supersonic speed so it is slowed down before it gets there.
SUBSONIC SPEEDS(TAKEOFF & CRUISE)
1. At take off the engines need maximum airflow, therefore the ramps are fully retracted and the auxiliary inlet vane is wide open Shortly after take Off the aircraft turns off re-heats and the power is reduced.
2. The secondary nozzles are opened further to allow more air to enter, therefore quietening down the exhaust. The Secondary air doors also open at this stage to allow air to by pass the engine
Unlike a regular aircraft with over 50 moving parts on wings a concorde has only 6 of them .
The design gives good lift at low airspeeds by increasing the angle of attack and it also performs at high speeds with very little drag.
As the aircraft gets closer to the ground, the downwash of the air between the wing and the ground creates a cushion . Hence landings are smooth.
For accurate weight and strength a copper based aluminium alloy called RR58 was used for this purpose . The process used was called sculpture milling .
Due to the process there was no welds or rivets anywhere on the wing ; hence strength was improved and about 700 pounds of material was saved .
Concorde has a tricycle landing gear layout, with a nose gear and 2 main gear. Separate from this configuration is a tail bumper gear that is fitted to prevent any damage to the fuselage
The nose gear is situated behind the flight deck, making taxing different to a normal aircraft and it also retracts forwards.
The main landing gear on Concorde was the first to be fitted with the now standard Carbon Fibre brakes that are seen on all aircraft today
MAIN LANDING GEAR:
Number of wheel on each bogie- 4
Retraction direction- Inwards
Tyre type- Michelin NZG
Tyre pressure- 232PSI
Brakes -4 X Dunlop Carbon Fibre with anti-skid system