VTVL technologies pplanes developed substantially with small rockets afterin part due to incentive prize competitions like the Lunar Lander Challenge. Archived from the original on At high jet planes landing and taking off 92 airports, an airplane requires more runway to take off. Once the wheels hit the deck, the pilot immediately pushes the aircraft to full throttle. Takeoff is the phase of flight in which an aircraft goes through a transition from moving along the ground taxiing to flying in the air, usually starting on a runway. Airbus A Embraer [19].

The catapult system is used for taking off, while the Fresnel lens and arresting wires are used to help the pilot land. These systems have been in place for several decades, and even though technology will improve drastically within the next 20 years, the future systems will continue to be based on these initial designs.

Wagner, Jr. The Navy currently uses Nimitz class aircraft carriers, which are typically 1, feet in length and have deck space of approximately 4. Below deck the ships hold up to 80 aircraft, 6, people, 2 nuclear reactors, and all the supplies needed for tours that can last several months [1], [2].

In order for the aircraft carrier to act as a true traveling airport, the pilots and crew rely on three key elements to launch and land aircraft safely.

First, four catapults are specially developed to launch planes at high speeds. Third, four arresting cables are in place to bring the plane to rest in less than feet [3]. Aircraft typically require long runways in order to gather enough speed so they can successfully take off.

Since the runway length on an aircraft carrier is only about feet [3], compared to the 2, feet needed for normal aircraft to take off from a runway [4], engineers have created steam-powered catapults on the decks of carriers that are capable of launching aircrafts from 0 to knots miles per hour in just 2 seconds [5]. The takeoff system can be broken down into two components — the above ground and below ground operations.

Figure 2: Blast Deflectors push harmful jet discharge into the air and away from the crew. The tow bar hangs off the front of the nose gear so the catapult can pull the aircraft [2].

In order to prevent harmful jet discharge from going into unwanted places, a jet-blast deflector is placed directly behind the aircraft, pushing the discharge up into the air see Fig.

The pilot then pushes the engine to full throttle, creating a forward thrust that would traditionally move a jet forward [5]. A holdback bar is in place to prevent any motion at this time, despite the thrust of the jet.

Once the force from the catapult is added to the thrust of the jet, the excess force will cause the hold-back bar to release and the jet will move [2]. This is because the hold-back bar can only hold the force from the jet at full thrust, but not the additional force of the catapult. Below Ground Below deck, steam is pumped into a capsule at extremely high pressures. Once a valve is released, steam travels up a long tube that runs the length of the catapult.

The pressure from the steam travels to several pistons, which are locked in place until the signal for their release is given. The pistons are attached to the catapult above by a pulley system located in a crack running the length of the runway [6]. Once the aircraft is at full throttle and the steam is creating pressure below deck, the pistons are released and pushed forward at high speeds. The force causes the holdback device, which is designed only to hold the force from the thrust of the jet, to release and shoot the jet from the ship into the air.

After completing its task, the catapult must be stopped quickly. A water brake system is attached to the end of the launch tube.

When the pistons hit the water brake, pressure from the water in the tube forces the pistons to quickly come to a halt [7]. The pulley system then rapidly retracts the catapult so that the next aircraft can be hooked up for launch. The retracted pistons push the steam through separate tubing so that it can be reheated and reused for later launches [6].

However, only rarely will the airplane actually operate under conditions that approximate standard atmosphere. Any increase in temperature or altitude means a decrease in the aircraft's optimum performance. Air density decreases with altitude.

At high elevation airports, an airplane requires more runway to take off. Its rate of climb will be less, its approach will be faster, because the true air speed [TAS] will be faster than the indicated air speed [IAS] and the landing roll will be longer. Air density also decreases with temperature. Warm air is less dense than cold air because there are fewer air molecules in a given volume of warm air than in the same volume of cooler air.

As a result, on a hot day, an airplane will require more runway to take off, will have a poor rate of climb and a faster approach and will experience a longer landing roll. In combination, high and hot, a situation exists that can well be disastrous for an unsuspecting, or more accurately, an uninformed pilot. The combination of high temperature and high elevation produces a situation that aerodynamically reduces drastically the performance of the airplane.

The horsepower out-put of the engines decrease because its fuel-air mixture is reduced. The propeller develops less thrust because the blades, as airfoils, are less efficient in the thin air. The wings develop less lift because the thin air exerts less force on the airfoils. As a result, the take-off distance is substantially increased, climb performance is substantially reduced and may, in extreme situations, be non-existent.

Humidity also plays a part in this scenario. Although it is not a major factor in computing density altitude, high humidity has an effect on engine power.

The high level of water vapor in the air reduces the amount of air available for combustion and results in an enriched mixture and reduced power.

Mountain airports are particularly treacherous when temperatures are high, especially for a low performance airplane. The actual elevation of the airport may be near the operational ceiling of the airplane without the disadvantage of density altitude. Under some conditions, the airplane may not be able to lift out of ground effect or to maintain a rate of climb necessary to clear obstacles or surrounding terrain.

Density altitud e is pressure altitude corrected for temperature. It is, in layman terms, the altitude at which the airplane thinks it is flying based on the density of the surrounding air mass. Too often, pilots associate density altitude only with high elevation airports.

Certainly, the effects of density altitude on airplane performance are increasingly dramatic in operations from such airports, especially when the temperature is also hot. Remember also that the standard air temperature value decreases with altitude. In order to compute the density altitude at a particular location, it is necessary to know the pressure altitude.

To determine the latter, set the barometric scale of the altimeter to Density altitude can be calculated for any given combination of pressure altitude and temperature, by using the circular slide rule portion of a flight computer. Your Airplane Flight Manual publishes information, usually in chart or table form, on the take-off performance of a specific model of airplane. In addition, under-inflated tires, dragging brakes, dirt on the wings, etc. If after calculating density altitude and checking the tables, it appears that the take-off run will require more runway than is available, you, as pilot-in-command, have several alternatives.

You can lighten the load, if possible, or you can wait until the temperature decreases. Generally, the most critical time for flight operations when the temperature is very hot is from mid-morning through mid-afternoon. This is especially true at high elevation airports, but even at lower elevations, aircraft performance may be marginal.

Aircraft operations should, therefore, be planned for early morning or late evening hours. It is important to remember that in taking off from airfields that are at high elevation, you should use as a reference the same indicated airspeed that you would use during take-off from an airfield at sea level. It is the true airspeed and groundspeed that is affected by the increase in elevation and temperature. Your Airplane Flight Manual also publishes data for climb performance.

The maximum, or best rate of climb, is the rate of climb which will gain the most altitude in the least time and is used to climb after take off until ready to leave the traffic circuit.

Rotorcraft utility Tiltrotors. Business jets Light-sport aircraft Roadable aircraft. By date and usage By tail number Most-produced. Military aircraft. Categories : Lists of aircraft. Hidden categories: CS1 maint: archived copy as title Articles with short description Short description is different from Wikidata. Namespaces Article Talk. Views Read Edit View history. Help Learn to edit Community portal Recent changes Upload file. Download as PDF Printable version.

Antonov An Scaled Composites Model Stratolaunch. Airbus A [1] [2] [3]. Boeing F. Boeing ER. Antonov An M. Lockheed C-5 Galaxy [4] [5] [6]. Boeing [7]. Airbus A [8]. Airbus A Airbus A [8] [9]. McDonnell Douglas MD McDonnell Douglas DC Boeing [10]. Airbus A [8] [11]. Airbus A [12] [13]. Lockheed L Airbus AR [14]. Airbus A [14]. Boeing B [15]. Boeing C [15]. Airbus AM. Boeing B [16].

Router For Woodwork Interface Woodworking Plans Christmas Yard Decorations Review Ogee Bit For Sale 50