Project-1: Powertrain for aircraft in runways

Project-1: Power Train for Aircraft in Runway

1. Search and list out the total weight of various types of aircraft.

Various types of aircraft weight considered are as followed.

Maximum Taxi Weight (MTW)

The maximum taxi weight is the maximum weight authorized for maneuvering (taxiing or towing) an aircraft on the ground as limited by aircraft strength and airworthiness requirements. It includes the weight of taxi and run-up fuel for the engines and the APU.

Maximum Take-off Weight (MTOW)

The maximum take-off weight is the maximum weight authorized at brake release for take-off, or at the start of the take-off roll. The maximum take-off weight is always less than the maximum taxi weight as the fuel burned during taxi by the engines and the APU are reduced.

Maximum Landing Weight (MLW)

The maximum weight authorized for the normal landing of an aircraft. The MLW must not exceed the MTOW. The fuel load of the plane is reduced during the journey.

Maximum Zero-Fuel Weight (MZFW)

The maximum permissible weight of the aircraft less all usable fuel and the other specified usable agents. It is the maximum weight permitted before usable fuel and other specified usable fluids are loaded in specified sections of the airplane.

Take-off Run (TOR)

The length of the runway declared available and suitable for the ground run of an airplane taking off.

Landing Run (LR)

The length of the runway that is declared available and suitable for the ground run of an airplane landing.

Total weight of various types of Aircraft.

Type	MTOW [kg]	MLW [tonnes]	TOR [m]	LR [m]	ICAO category	FAA category
Antonov An-225	640,000	591.7	3500		Heavy	Super
Airbus A380-800	575,000	394	3100	1930	Super	Super
Boeing 747-8f	447,700	346.091	3100	1800	Heavy	Heavy
Boeing 747-8	443,613	306.175	3100		Heavy	Heavy
Boeing 747 – 400ER	412,770	295.742	3090		Heavy	Heavy
Antonov An-124-100M	405,060	330	2520	900	Heavy	Heavy
Boeing 747-400	396,900	295.742	3018	2179	Heavy	Heavy
Lockheed C-5 Galaxy	381,000	288.417	2530	1494	Heavy	Heavy
Boeing 747-200	377,840	285.7	3338	2109	Heavy	Heavy
Boeing 747-300	377,840	260.320	3222	1905	Heavy	Heavy
Airbus A340-500	371950	240	3050	2010	Heavy	Heavy
Airbus A340-600	367,400	256,	3100	2100	Heavy	Heavy
Boeing 777F	347,800	260.816	2830		Heavy	Heavy
Boeing 777-300ER	351,800	251.29	3100		Heavy	Heavy
Boeing 777- 200LR	347,450	223.168	3000		Heavy	Heavy
Boeing 747-100	340,200	265.3			Heavy	Heavy
Airbus A350-1000	308	233.5			Heavy	Heavy
Boeing 777-300	299,370	237.683	3380		Heavy	Heavy
Boeing 777-200ER	297,550	213	3380	1550	Heavy	Heavy
Airbus A340-300	276,700	190	3000	1926	Heavy	Heavy
McDonnell Douglas MD-11	273,300	185	2990	1890	Heavy	Heavy
Airbus A350-900	270,000	175	2670	1890	Heavy	Heavy
Ilyushin II-96M	270,000	195.40	3115	2118	Heavy	Heavy
McDonnell Douglas DC-10	256,280	183	2990	1890	Heavy	Heavy
Boeing 787-10	254,000	201.849			Heavy	Heavy
Airbus A340-200	253,500	181	2990		Heavy	Heavy
Ilyushin IL-96-300	250,000	175	2600	1980	Heavy	Heavy
Airbus A330-300	242,200	185	2500	1750	Heavy	Heavy
Airbus A330-200	242,000	180	2220	1750	Heavy	Heavy
Lockhead L-1011-500	231,300	166.92	2636		Heavy	Heavy
Ilyushin IL-86	208,000	175			Heavy	Heavy
Boeing 767-400ER	204,	158.758	3414		Heavy	Heavy
Airbus A300-600R	192,00	140	2385	1555	Heavy	Heavy
Boeing 767-300ER	187,000	136.08	2713	1676	Heavy	Heavy
Concorde	185,000	111.1	3440	2220	Heavy	Heavy
Airbus A300-600	163,000	138	2324	1536	Heavy	Heavy
Boeing 767-300	159,000	136.078	2713	1676	Heavy	Heavy
Airbus A310-300	157,000	151.9			Heavy	Heavy
Vickers VC10	152,000	151.9			Heavy	Heavy
Boeing 707-320B	151,000	97.5			Heavy	Heavy
Boeing 707-320C	151,000	112.1			Heavy	Heavy
Douglas DC-8-61	147,000				Heavy	Heavy
Airbus A310-200	142,000	123	1860	1480	Heavy	Heavy
Airbus A400M	141,000	122	980	770	Heavy	Heavy
Douglas DC-8-32	140,000				Heavy	Heavy
Douglas DC-8-51	125,000				Medium	Large
Boeing 757-300	124,000	101.6	2550	1750	Medium	Large
Boeing 707-120B	117,000	86.3			Medium	Large
Boeing 757-200	116,000	89.9	2347	1555	Medium	Large
Boeing 720B	106,000	79.5			Medium	Large
Boeing 720	104,000	79.5			Medium	Large
Tupolev Tu-157M	104,000	80			Medium	Large
Tupolev Tu-204SM	87,500	87.5	2250		Medium	Large
Convair 880	87,500				Medium	Large
Boeing 737-900	85,000	66.36	2500	1704	Medium	Large
Boeing 737-900ER	85,000	71.35	2804	1829	Medium	Large
Boeing 727-200 Adnvcd	84,000	70.1			Medium	Large
Airbus A321-100	83,000	77.8	2200	1540	Medium	Large
Boeing 737-800	79,000	65.32	2308	1634	Medium	Large
Boeing 727-200	78,000	68.1			Medium	Large
McDonnell-Douglas Md-83	73,000	63.28			Medium	Large
Boeing 727-100	72,500	62.4			Medium	Large
Boeing 727-100C	72,500	62.4			Medium	Large
McDonnell-Douglas MD-90-30	71,000	64.41	2165	1520	Medium	Large
de Havilland Comet 4	70,700				Medium	Large
Boeing 737-700	70,000	58.06	1921	1415	Medium	Large
Boeing 737-400	68,000	54.9	2540	1540	Medium	Large
de Havilland Comet 3	68,000	54.66	1796	1340	Medium	Large
Boeing 377	67,000				Medium	Large
Boeing 737-600	66,000	54.66	1796	1340	Medium	Large
Hawker Siddeley Trident 2E	65,000				Medium	Large
Airbus A319	64,000	62.5	1850	1470	Medium	Large
Boeing 737-300	60,000	49.9	1832	1360	Medium	Large
Airbus A220-100	59,000	50.80	1463	1356	Medium	Large
Airbus A220-100	59,000	57.5	1375	1340	Medium	Large
Boeing 717-200HGW	55,000	47.174	1950		Medium	Large
Douglass Dc-7	55,000				Medium	Large
de Havilland comet 2	54,000				Medium	Large
Douglas DC-6A	48,600				Medium	Large
Embraer 190	48,000	43	2056	1323	Medium	Large
Caravelle lll	46,000	39.95	1621	1350	Medium	Large

2. Difference between ground speed and airspeed:

The difference between ground speed and airspeed is caused by the influence of winds on the overall velocity of the aircraft.

The true airspeed is simply the speed at which an aircraft is moving relative to the air it is flying in. As such, it’s also the speed at which the air is flowing around the aircraft’s wings. Ground speed, on the other hand, is the aircraft’s speed relative to the ground. One thing that should be noted here is that it’s horizontal rather than vertical speed, an aircraft climbing completely vertically would have a ground speed of zero. In other words, while airspeed is what determines how fast an aircraft will get to its destination.

Ground Speed:

For a reference point picked on the ground, the aircraft moves relative to the reference point at the ground speed. Ground speed is also a vector quantity. So a comparison of the ground speed to the wind speed must be done according to rules for vector comparisons.

Airspeed:

The important quantity in the generation of lift is the relative velocity between the object and the air, which is called the airspeed. Airspeed cannot be directly measured from a ground position, but must be computed from the ground speed and the wind speed. Airspeed is the vector difference between the ground speed and the wind speed.

Airspeed = ground speed – wind speed

On a perfectly still day, the airspeed is equal to the ground speed. But if the wind is blowing in the same direction that the aircraft is moving, the airspeed will be less than the ground speed.

Wind speed:

For a reference point picked on the ground, the air moves relative to the reference point at the wind speed. Notice that the wind speed is a vector quantity and has both a magnitude and a direction. Direction is important. A 20mph wind from the west is different from 20mph wind from the east. The wind has components in all three primary directions (north-south, east-west, and up-down). A positive velocity is defined to be in the direction of the aircraft’s motion. We are neglecting crosswinds, which occur perpendicular to the flight path but parallel to the ground and updrafts and downdrafts, which occur perpendicular to the ground.

3. Why it is not recommended to use aircraft engine power to move it on the ground at the airport.

It is not recommended to use aircraft engine power to move it on the ground at airport because there are certain extreme conditions for it. The term aircraft ground running is usually used to describe the operation of some or all of the engines of an aircraft, whilst on the ground, for the purpose of functionality checking the operation of either engines or aircraft systems. This takes place prior to the release to service of an aircraft from maintenance. Ground running may be carried out either prior to, during or after the rectification of a defect or scheduled work on an engine. Although the aircraft may need to be taxied or towed to an approved ground running position under a clearance from ATC, most operators and maintenance organisations do not require pilots to be on board because aircraft technicians can be trained and approved for these duties.

Jet blast is the phenomenon of rapid air movement produced by the jet engines of aircraft particularly on or before take-off. A large jet-engine aircraft can produce winds of up to 100 knots (190 km/hr) as far as 60 meters behind it at 40% maximum rated power. Jet blast can be a hazard to people or other unsecured objects behind the aircraft and is capable of flattening buildings and destroying vehicles. The immediate area in front of a jet engine creates an area where people and equipment can be sucked in to the engine if anything is too close to the intake. So in order to avoid such conditions it is not recommended to use aircraft engine power to move it on the ground at the airport.

4. How an aircraft is pushed to the runway when its ready to take-off?

The aircraft is pushed to the runway using a taxing vehicle. Taxiing refers to the movement of an aircraft on the ground, under its own power. The aircraft moves on wheels. An airplane uses taxiways to taxi from one to another place, for moving inside terminal. The aircraft always moves on the ground following the yellow lines, to avoid any collision with the surrounding buildings, vehicles or other aircraft. The taxiing motion has a speed limit. Before making a turn, the pilot reduces the speed further to prevent tire skids. The aircraft that are landing or takinf off have higher priority. The other aircraft have to wait for these aircraft before they start or continue taxiing.

The thrust to propel the aircraft forward comes from its propellers or jet engines. Steering is achieved by turning a nose wheel or tail wheel/rudder; the pilot controlling the direction travelled with their feet. The use of engine thrust near terminals is restricted due to the possibility of jet blast damage. This is why the aircraft is pushed back from the buildings by a vehicle before they can start their own engines for taxiing.

Take-off power

Take-off is the phase of flight in which an aircraft goes through a transition from moving along the ground to flying in the air and during this phase the engines are run at full power during take-off. Aircraft employ the concept of the take-off V-speeds, V1 and V2. These speeds are determined not only by the above factors affecting take-off performance but also by the length and slope of the runway. Below V1, in case of critical failures, the take-off should be aborted; above V1 the pilot continues the take-off and returns for landing. After the co-pilot calls V1, then V2(the safe takeoff speed) is called. This speed must be maintained after an engine failure to meet performance targets for the rate of climb and angle of climb. The power required to achieve the take-off speed is take-off power.

Tyre Design:

Tires are used to absorb the shock of landing and provide cushioning. It is made up of three components steel, rubber and fabric. It also provides the necessary traction for braking and stopping of an aircraft. An aircraft tire is designed to withstand extremely heavy loads while landing, take-off, taxiing and parking. The number of wheels required for aircraft increases with the weight of the aircraft, as the weight of the airplane needs to be distributed more evenly.

Tread: the tread is made of rubber mixed with other additives to obtain the desired level of toughness, durability and resistance to wear. The tread pattern is designed to aircraft operational requirements with the ribbed tread design used widely due to its good traction under varying runway conditions.

Sidewall: the sidewall is a protective layer of rubber that covers the outer casing ply. It extends from the tread edge to the bead area.

Tread reinforcing ply: one or more layers of fabric that strengthens and stabilizes the tread area for high-speed operation. It also serves as a reference for the buffing profess when tires are retreaded.

Breakers: breakers are reinforcing plies of rubber-coated fabric placed under the buff line cushion to protect casing plies and strengthen and stabilize the tread area. They are considered and integral part of the casing construction.

Casing piles: alternate layers of rubber-coated fabric (running at opposite angles to one another) provide the strength of the tire.

Wire beads: hoops of high tensile strength steel wire that anchor the casing plies and provide a firm mounting surface on the wheel. The outer edge of the bead that fits against the wheel flange is called the bead heel. The inner bead edge is called the bead toe.

Apex strip: a wedge of rubber affixed to the top of the bead bundle.

Flippers: layers of rubberized fabric that help anchor the bead wires to the casing and improve the durability of tire.

Ply turnups: the casing plies are anchored by wrapping them around the wire beads, thus forming the ply turnups.

Chafer: a protective layer of rubber and fabric located between the casing plies and wheel to minimize chafing.

Liner: In tubeless tires, the liner is a layer of low permeability rubber that acts as a built-in tube and restricts gas from diffusing into the causing plies. In tube-type tires, a thinner liner is used to prevent tube chafing against the inside ply.

Rolling Resistance:

It is the resistance that the tires offer against the motion while on the ground. In cases of aircrafts rolling resistance can be experienced while take-off and while landing.

Tire Pressure:

Aircraft tires: generally operate at high pressures, up to 200psi for airliners. Overinflation can damage the tires by causing uneven traed war, reduced traction, increased susceptibility to cutting and increased stress on the wheel assemblies, underinflation is by far more damaging. Underinflation produces uneven tead wear and shortens tire life due to excessive flex heating. The bead area of an underinflated tire can be 50 percent hotter than that of a properly inflated one. Heat is damaging to tire rubber compounds and fabrics. It contributes to tread and carcass seperations and bead failures.

Brakes forces when landing:

Brake systems have an anti-lock braking system (ABS) that prevents the tires from sliding down a wet runway. The advantage of the automatic brake system is that the aircraft brakes comfortably at a constant deceleration. Passengers experience a constant force that presses them into their seats. The brake system automatically applies the wheel brakes just enough to create them into their seats. The brake system automatically applies the wheel brakes just enough to create a constant deceleration independent of the air resistance, spoilers and reverse thrust. It is only in the last phase of braking, known as the rollout, that the pilot takes over the wheel brakes by pressing on both brake pedals. This deactivates the automatic brake system. Immediately after landing, the aircraft is still moving fast enough that aerodynamic devices are much more efficient than the brakes.

Electric Brakes

The brake system sends an electronic signal to the left and right brake system control units (BSCUs). These then send signals to the four electronic brake actuator controllers (EBAC) which control the rate of braking on the wheels. Each wheel has four electric brake actuators (EBA), a kind of piston which presses against the carbon brake discs. The brake discs themselves are made up of two parts. Firstly there are the rotors. These are connected to the wheel by drive tabs. As these drive tabs are in contact with the inside of the wheel, they spin at the same speed. Depending on the brake manufacturer, there are either four or five of these rotors on each brake assembly. The second part of the discs is the stators. These sit around each rotor and are fixed in place and thus don’t move. As the wheel turns, the rotors spin round inside the stators.

There are two other systems that help slow the aircraft down on landing are spoilers and the reverse thrust.

Spoilers:

The spoilers are used to spoil the airflow over the wing. This dumps any remaining lift the wings are generating, allowing the wheels to take all the weight and achieve maximum efficiency from the brakes.

Reverse thrust:

The final part of the gracing process comes from the reverse thrust. Just after we have touched down, we pull two levers on top of the thrust levers to engage the reverse thrust by a reverse gear for jet engines. There are two stages of reverse thrust- idle reverse and max reverse. The idle reverse is used on most landings and the max reverse is used when the landing performance requires it, normally when the aircraft is landing at hot or high elevation airfields.