If you're a techno fan, this is best played loud. If not, well...
0:00 Wing flex. 154% load.
1:11 Brakes tested at max TO weight, all tires at minimum allowable tread. Braking begins at V1 decision speed. Fuse plugs in the tires melt allowing tires to deflate before they explode.
2:31 Stall tests
2:41 Crosswind tests
3:04 Vmu: Minimum Unstick speed. Speed the aircraft takes off with maximum takeoff angle. Used to calculate Lift Off speed.
3:16 Ram Air Turbine (RAT) for providing emergency power and hydraulic pressure in the event of a dual generator failure (i.e. dual engine failure).
3:25 Contaminated runway test.
Airbus A380 Flutter Test
Flutter Excitation
One of the most dangerous events that can occur in flight is a phenomena called "flutter". Flutter is an aerodynamically induced vibration of a wing, tail, or control surface that can result in total structural failure in a matter of seconds. The prediction of flutter is not a precise science and requires flight verification that flutter will not occur within the normal flight envelope.
The aerodynamic surfaces of an airplane are constructed so that they can carry the loads that are produced in flight. For example the wing must be capable of supporting the weight of the airplane as well as the additional lift produced during turning flight. The resulting wing structure can be viewed as a blade or spring extending from the fuselage. If we "tap" the spring with a hammer, it will vibrate at a frequency which relates to the stiffness of the spring. A stiff spring will vibrate at a higher frequency than a more limber spring. This frequency is known as the "natural frequency" of the spring.
Flutter will usually occur at or near the natural frequency of the structure, that is, some small aerodynamic force will cause the structure to vibrate at its natural frequency. If this small force persists at the same frequency as the natural frequency of the structure, a condition called "resonance" occurs. Under a resonant condition, the amplitude of the vibration will increase dramatically in a very short time and can cause catastrophic failure in the structure.
The aerodynamic forces which can induce flutter are related to the dynamic pressure, or airspeed, of the airplane. If flutter-inducing forces are present they will increase as the airspeed is increased. Flutter characteristics can be explored by "tapping" the surface at progressively faster airspeeds, then watching how fast the vibrations decay or damp out. The vibrations will take longer to decay as the airspeed approaches a possible resonant condition. In this way potential flutter can be approached safely without actually reaching the resonant condition and experiencing sustained flutter.
The method for "tapping" the surface varies. On some airplanes a sharp control pulse is sufficient to excite the natural frequency of the surface. In most cases a special flutter excitation device is installed. This device will use either an aerodynamic vane or an unbalanced mass which is driven back and forth at the known natural frequency of the surface. The device is abruptly turned off and the natural damping characteristics of the vibrating surface are revealed. The analysis is similar to the frequency and damping analysis discussed under the "control pulse" maneuver, except that the structural (or flutter) frequencies are much higher.
Boeing 777 tailstrike (VMU Test)
The VMU Test performed on the 777-200. Sorry about the monents of weard soundings. This video is over 10 years old. PBS owns the footage shown.
Airbus A380 Tail Strike Test
Full video of the Airbus A380 Tail Strike Testing also known as VMU testing. The A380 Scrapes the tail during a test.
Impressive Qatar Airways Boeing 787 Dreamliner Display, Farnborough.
Ex F-18 Super Hornet display pilot Mike Bryan, gets to fly the Boeing 787 at Farnborough.
Video with narrative/ http://www.youtube.com/watch?v=jRtXLXEDvNM
Amazing how this airliner flew at FIA12, great flying and the Dreamliner looked really good, those wings are things of beauty.
Cheap tyres versus expensive tyres - What Car?
For more whatcar.com news visit: http://www.whatcar.com/car-news
Cheap rubber might be easy on your wallet, but is it really worth the saving? We tested a selection of budget tyres against three premium brands to find out.
Tire Force Test
The only way to get information on tires, not from books and theories, but from tests
Airbus A380 Tail Strike Test [VMU Test]
Tailstrike is an aviation term that describes an event in which the rear end of an aircraft touches (strikes) the runway. This can happen during takeoff of a fixed-wing aircraft if the pilot pulls up too rapidly, leading to the rear end of the fuselage touching the runway. It can also occur during landing if the pilot flares too aggressively. This is often the result of an attempt to land nearer to the runway threshold.
A tailstrike is physically possible only on an aircraft with tricycle landing gear; with a tail dragger configuration, the tail is already on the ground. Some delta wing aircraft, which require a high angle of attack on takeoff, are fitted with small tailwheels to prevent tailstrikes. Examples include the Concorde and Saab Draken. Some aircraft, such as the Diamond Aircraft Industries Diamond DA20, have a permanent skid installed to protect the airframe in the event of a tailstrike. Others may be fitted with a temporary skid as tailstrikes are sometimes purposefully carried out during the certification of new aircraft.
Tailstrike incidents rarely cause significant damage or cause danger, but may cause financial losses as the planes have to be thoroughly inspected and repaired.
However, improper repair to the damaged airframe after tailstrikes accidents may be responsible for fatal accidents that occur years later (including the worst single-aircraft accident as of 2008, the accident involving the Japan Airlines Flight 123) due to structural failure of the airframe at the site of the tailstrike after repeated cycles of pressurization and depressurization at the weak point of improper repair.
