Project-1: Powertrain for aircraft in runways

1)

The weight of the aircraft must be determined by the pilot for each flight to guarantee that the aircraft stays within the manufacturer's weight limits. These restrictions are in place to ensure that the aircraft can perform and recover from all flight manoeuvres, as well as endure structural loading.

Weights of Common Airplanes

The following is a list of some of the most prevalent aircraft flying in our skies today:

Aircraft Empty Weight (AEW):

• This is also known as OEW - Operating Empty Weight, and it is the weight of the aircraft with all of its equipment but no fuel, passengers, or cargo.

Aircraft Maximum Gross Takeoff Weight (MGTW):

• The greatest weight an aeroplane can have as it takes off from the ground is known as the MGTW, or Maximum Gross Takeoff Weight. The empty weight of the aeroplane, the fuel, the crew, the passengers, and all the cargo are included in this.
• This weight restriction is absolute and was established by the manufacturer. An overweight aircraft has been the root cause of many aviation mishaps because the pilot(s) lacked the strength or dexterity to avoid them.

Aircraft Useful Load:

• The maximum weight that a pilot can carry in an aircraft. Take the MGTW figure and subtract the AEW to get the total useful load that the aircraft can carry.
• This is the fuel, the crew, the passengers, and the cargo.
• The greater the load, the greater the utility of the aircraft to its customers!

How Fuel, Passengers, and Cargo Affect Aircraft Weight:

• Each item of weight added to the aircraft must be accounted for; some items can be omitted from the flight, while others cannot. There are several scenarios we can consider, and for these examples, I'll use the Astar helicopter I fly because the math is simple:

2)

Wind Speed:

• When a reference point on the ground is selected, the air moves relative to the reference point at the wind speed. It's worth noting that wind speed is a vector quantity with both a magnitude and a direction. Direction is essential. A 20-mph wind from the west is not the same as a 20-mph wind from the east. The wind is composed of elements from all three primary directions (north-south, east-west, and up-down).
• Only velocities along the aircraft's flight path are considered in this figure. A positive velocity is defined as motion in the direction of the aircraft. Cross winds, which occur perpendicular to the flight path but parallel to the ground, as well as updrafts and downdrafts, which occur perpendicular to the ground, are ignored.

Ground speed :

• When a reference point on the ground is selected, the aircraft moves relative to the reference point at ground speed. Because ground speed is also a vector quantity, the comparison of ground speed to wind speed must follow vector comparison rules.

Airspeed:

• The airspeed, or relative velocity between the object and the air, is an important quantity in the generation of lift. Airspeed cannot be measured directly from a ground position, but must be calculated from ground speed and wind speed. The vector difference between ground speed and wind speed is known as airspeed.

Ground Speed - Wind Speed = Airspeed

• On a perfectly still day, airspeed equals ground speed. However, if the wind is blowing in the same direction as the aircraft, the airspeed will be slower than the ground speed.

3)

• The aeroplane utilises its own engine power to move around on the ground, which is known as taxiing.
• In general, most aeroplanes can move in reverse by employing reverse thrust technology. However, in most practical instances, this is not viable because when aeroplanes use reverse thrust, they use a lot of fuel, make a lot of noise, and are dangerous to anyone working nearby.
• Another reason why reverse thrust should not be used is that the jet blast could cause damage to the terminal building or equipment. Because the engine is so close to the ground, it will blow sand and debris forward and suck it into the engine, inflicting damage.
• As a result, there are pushback trucks at the airport. A pushback truck elevates the front wheel of an aeroplane; their duty at most airports is to tow the aircraft away from the parking space and onto the taxiways.

4)

• Pushback is an aviation procedure in which an aircraft is pushed backward from its parking position, typically at an airport gate, by an external power source. Pushbacks are performed by low-profile vehicles known as pushback tractors or tugs.
• Although many aircraft can move backward on the ground using reverse thrust (a procedure known as a powerback), the resulting jet blast or prop wash would cause increased noise, damage to the terminal building or equipment, and injury to airport personnel due to high-speed debris. This debris would also be sucked into the engine during normal operation, causing excessive wear - ground use is a major cause of wear on aircraft engines. When ground-handling aircraft, a pushback is therefore the preferred method.
• Pushbacks at congested airports are typically subject to ground control clearance to allow for ground movement on taxiways. Once clearance is obtained, the pilot will communicate with the tractor driver (or, in some cases, a ground handler walking alongside the aircraft) to begin the pushback. A headset connected near the nose gear can be used to communicate.
• Because the pilots cannot see what is behind the aircraft, the pushback tractor driver steers instead of the pilots. Depending on the aircraft model and airline policy, a bypass pin may be temporarily inserted in the nose gear to detach it from the aircraft's usual steering mechanism.
• When the pushback is finished, the towbar is disengaged and any bypass pins are removed. The ground handler will show the pilots the bypass pin to demonstrate that it has been removed. The pushback is then over, and the aircraft may taxi ahead on its own.

5)

Take-off Power

The maximum power that an engine can provide at a brief time in order to lift flight. Takeoff power is typically only used for up to 5 minutes with reciprocating engines and up to 212 minutes with gas turbine engines. This could not always be the situation. For reciprocating engines specifically, it refers to the braking horsepower produced under typical sea level conditions, as well as under the highest crankshaft rotational speed and engine manifold pressure permitted for normal takeoff. It can only be used continuously for the time frame indicated in the authorised engine specifications.

Regarding gas turbine engines, the thrust produced under static circumstances at a given altitude and atmospheric conditions of the rotor shaft rotational speed and gas temperature approved for the typical takeoff. It can only be used continuously for the time frame indicated in the authorised engine specifications.

Tyre Design:

• The tryes act as a cushion and assist in absorbing the impact of landing. Additionally, it gives an aeroplane the traction it needs to brake and halt.
• A plane's tyres are made to resist incredibly heavy weights during takeoff, landing, taxing, and parking. As the weight of the aircraft must be distributed more equally, the number of wheels needed to support the aircraft rises as it gets heavier.

Rolling resistance:

• Along with the more well-known forces such as thrust, weight, lift, and drag, there is also a rolling resistance force (FR) brought on by friction between the ground and the tyres. The rolling resistance force works against the traction force of the aircraft whether it is towing, taxiing to drive it onto the runway, or doing a takeoff roll.
• This rolling resistance force is determined by a number of variables, including the road's surface, its roughness, whether it is dry or wet, the tyre pressure, its substance, its temperature, its thread pattern, etc.
• Values change depending on speed. As tyre pressure rises and falls, its value must be carefully selected taking common situations into account.

Tyre Pressure

• Aeroplane tyres can have tubes or be tubeless. Tyres without tubes have an advantage over those with tubes. In more contemporary aviation, tube-type tyres are no longer used. All modern aeroplanes have tubeless tyres. The word TUBELESS is printed on the sidewall of tyres that are intended to be operated without tubes.
• Variations in tyre pressure exist between aircraft.The conventional compressed air we would use from a gas station supply or a home air compressor is not used by the tyres.
• Aviation tyres are much more durable than the tyres we use in the auto industry, and they are actually inflated with nitrogen gas rather than compressed air.

• This gives the tyres more general strength to sustain the heavy loads they bear while moving the plane or during takeoff and landing.
• They often run the tyres at 200 to 220 PSI, depending once more on the model aircraft (Automobile run 30-40 PSI on average).
• Every 300 to 400 cycles, tyres must be replaced. One cycle stands for a landing and one for a takeoff. A plane lands and takes off, and this is seen as two cycles.
• Tire pressure that is too low results in excessively high rolling resistance figures.

Brake forces when landing:

• Few people are aware of how an aeroplane works, despite the fact that they are now among the most practical modes of transportation. As everyone is aware, a plane lands at a high speed—typically 16 mph. How can a plane decelerate safely in this situation, given that it is approaching at such a high speed?
• We must comprehend how braking functions in all wheeled vehicles, not just aeroplanes, in order to comprehend the solution to this query. As we already discussed, friction is formed on the wheels as a result of the torque that the braking process applies to them. The car stops as a result of the friction it creates with the ground, which causes it to lose kinetic energy.
• However, friction is peculiar in that it solely depends on the weight of the vehicle. When an aeroplane is landing, the aerodynamic lift reduces the plane's weight to zero; as a result, the brakes on the wheels are essentially useless for stopping the aircraft. Because of this, the aircraft must find alternate means of stopping until both the aerodynamic lift and the speed have achieved an adequate level. To do this, modern aircraft employ a variety of braking systems, including:

6A)

6B)

Simulink block diagram

• When calculating resistive forces, product blocks are used to feed factors like mass, coefficients, and other parameters.
• Total resistive forces can be determined using sum block.
• Display blocks are used to visually represent the outcomes.

7A)

Block Diagram of EV

Simulink Model:

Input:

Output

Battery paramaters

It can be seen that when reference speed is reversed, the motor voltage gets reversed by controller to change the direction of rotation. The current spike can be seen at this particular instant because back emf will be high at the instant of reversal of motor polarity.

7B)

Parameters are calculated in Excel as shown below