How is the load factor increment when encountering vertical gust defined? What does this equation tell us?

\(delta n=delta L/(m*g)=Kg*(rho*U*V*CLalpha)/(2*m*g/S)\) The AC sensitivity to gust is a function of wing loading (2 m g/S), lift curve slope (cL alpha-->depends on wing aspect ration), flight altitude and airspeed.

What is the MZFW critical for? What is the MRW critical for?

The MZFW is critical for wing bending and shear at the limit load factor-> fuel weight alleviates these loads The MRW is critical for rolling, towing, braking loads on ground

What weight does the MZFW limit? What does it mean to keep the MZFW balanced with the MTOW?

The payload weight that can be carried. The MZFW should be as high as possible, while staying in balance with the MTOW. This means that the wing bending and shear at the limit load factor should be approximately the same at MTOW (with full tanks) and at MZFW.

What do odd numbers in the AC zoning system indicate? What do even numbers indicate?

Odd numbers mark the zones of the left side Even numbers zones on the right side of the AC, as seen by the pilot.

card2brain.ch

In a tension test, what does the constant E mean?

E is the normal modulus of elasticity or Young's modulus.

In an AC wing, the cross sectional area of the web carry all the

bending moment

shear loads

compression loads

bending moment

shear loads

compression loads

The web carries most of the

shear load

bending moment

compression loads

shear load

bending moment

compression loads

The torsion loading on a trapezoidal wing section with no sweepback is maximum at

the wing root

the wing tip

the wing root

the wing tip

The local aerodynamic heating at stagnation point is

where part of the kinetic energy of air is converted into heat.

where part of the kinetic energy of air is lost.

where part of the kinetic energy of air is converted into heat.

where part of the kinetic energy of air is lost.

The hottes part of an AC flying at supersonic speed is

at the nose

at the wing tip

at the wing roots

at the airframe

at the nose

at the wing tip

at the wing roots

at the airframe

At low speeds the load factor is limited by

the maximum lift that the aircraft can generate.

design to a fixed value.

the maximum lift that the aircraft can generate.

design to a fixed value.

At high speed, the limit is set by

design to a fixed value.

the maximum lift that the aircraft can generate.

design to a fixed value.

the maximum lift that the aircraft can generate.

What are the load factor limits for the Pilatus-21 turboprop trainer?
For the Lockheed Martin F-22 Raptor jet fighter?

+8/-4
+9.5/-3.5

How is the load factor increment when encountering vertical gust defined?
What does this equation tell us?

\(delta n=delta L/(m*g)=Kg*(rho*U*V*CLalpha)/(2*m*g/S)\)
The AC sensitivity to gust is a function of wing loading (2 m g/S), lift curve slope (cL alpha-->depends on wing aspect ration), flight altitude and airspeed.

How do AC actually react to vertical gust?

They accelerate upwards, so the net gust velocity is reduced.

How do Airworthiness specifications define the gust velocities to determine load factors due to turbulence?

They define the standard gust velocities (in equivalent airspeed).

The AC weight influences loads on the AC structure. What kind of loads are these?

Fuselage bending
Wing bending
Shear loads
Tailplane loads

How do airworthiness regulations limit the minimum MLW for the PC-12?

95% of the MTOW--> the AC must be able to land immediately in case of engine failure and cannot dump fuel in emergency.

For multi engine AC equipped with a fuel jettison system, a lower MLW can be specified.

What is the MZFW critical for?
What is the MRW critical for?

The MZFW is critical for wing bending and shear at the limit load factor-> fuel weight alleviates these loads
The MRW is critical for rolling, towing, braking loads on ground

What weight does the MZFW limit?
What does it mean to keep the MZFW balanced with the MTOW?

The payload weight that can be carried. The MZFW should be as high as possible, while staying in balance with the MTOW.
This means that the wing bending and shear at the limit load factor should be approximately the same at MTOW (with full tanks) and at MZFW.

What defines the zoning system in the ATA-100 specification?

The zoning system is specified to simplify the location of parts in modern large transport AC.

How many hierarchies of AC zones are defined?

3: Major zones, Intermediate zones, Minor zones

What do odd numbers in the AC zoning system indicate?
What do even numbers indicate?

Odd numbers mark the zones of the left side
Even numbers zones on the right side of the AC, as seen by the pilot.

What can the skin of the AC's fuselage be made of?

Fabric, plywood (Sperrholz), thin metal sheet or synthetic materials.

Layout of a tricycle undercarriage:

How much should the pitch angle Θ be at which the tail touches the ground?

Tastatur-Befehle:

= drehen,

= vor-/rückwärts,

= scrollen

10-15°

How much should the roll angle be for large transport AC and for light AC?

Tastatur-Befehle:

= drehen,

= vor-/rückwärts,

= scrollen

at least 8° for large transport AC
15° for light AC

Which two limit angles define the required length of the main landing gear legs?

Tastatur-Befehle:

= drehen,

= vor-/rückwärts,

= scrollen

Ground pitch and roll angles

What loads should be on the nosewheel of the AC?

Tastatur-Befehle:

= drehen,

= vor-/rückwärts,

= scrollen

8-15% of the AC weight

For a general aviation or commuter AC, what maximum value of lift can be assumed for design and testing?

Tastatur-Befehle:

= drehen,

= vor-/rückwärts,

= scrollen

2/3 of the AC weight

On which value does the vertical speed at touchdown depend?

Tastatur-Befehle:

= drehen,

= vor-/rückwärts,

= scrollen

On the efficiency of the shock absorber.

What is the safety margin of a stroke?

Tastatur-Befehle:

= drehen,

= vor-/rückwärts,

= scrollen

2.5cm

What is a typical value for the internal gas pressure p₀ of AC oleo shock absorbers under static load?

Tastatur-Befehle:

= drehen,

= vor-/rückwärts,

= scrollen

1800psi (12.5 MPa)

What is shimmy and why can it occur?

Tastatur-Befehle:

= drehen,

= vor-/rückwärts,

= scrollen

Shimmy is high speed vibration of the nose wheel and can occur because of the wheel imbalance, tire wear or free play in the wheel suspension mechanism. A hydraulic damper (shimmy damper) must be fitted.

What is the typical lifetime of a wheel?

Tastatur-Befehle:

= drehen,

= vor-/rückwärts,

= scrollen

300-400 landings

Propeller efficiency:

A short take off AC with a low cruise speed will certainly benefit from a...

...large propeller providing high efficiency and high thrusts at low speeds.

For a fast AC,....

....a smaller propeller diameter will be more suitable.

Which peak efficiencies reach modern variable pitch propellers?

0.85-0.9

What describes feathering?

In the event of an engine failure, propeller pitch must be set to a value that reduces drag to a minimum. (90°)

Fuel Systems:

Fuel tanks:

How much weighs the fuel mass in an AC (except for small general aviation AC)?

25-50% of the MTOM

Fuel pumps:

What are transfer pumps?

Transfer pumps move fuel between tanks to maintain mass balance and to supply fuel to the collector ranks from where fuel is drawn to feed the engines.

What are booster pumps?

Also called engine feed pumps. They are used to boost (antreiben) the fuel pressure in the engine feed lines.

Another reason is to prevent cavitation (vapour bubbles) at high levels.

Valves:

What is the function of shut-off valves?

Shutting off fuel when required, preventing fuel transfer from one rank to another.

What are the functions of refuel and defuel valves?

Filling the tanks to allow flow from the refueling gallery to the fuel tanks, or from the tanks to the refueling gallery during defueling (emptying the tanks for maintenance)