Technical Flashcards
Tell me about the multi engine aircraft you flew during your training? (P06T)
The Technam P206T is a high-wing, twin engined, four seater Italian aircraft with a fully retractable landing gear.
It has a MTOW of 1230kg and a usable fuel capacity of 194L.
Its design allows for it to be one of the lightest multi-engined aircraft on the market for reasons such as:
- The landing gear attached to the fuselage rather than the wings
- Its Rotax 912 engines are small in size which significantly reduces the size of the engine cowling.
It has a max, ceiling of 14,000ft or 7,000 (OEI) and a max. demonstrated crosswind of 17kts.
Describe the engine on the P06T
it has 2x 4-cylinder, 4-stroke Rotax 912 S3 engines that are smaller and lighter than other piston engines, which allows for a significant reduction in drag and weight due to the smaller cowl size.
The cylinders are liquid-cooled which allows for much shorter fins to cool the cylinders, allowing the barrels to be significantly smaller, further reducing the size of the engine cowl.
Each engine is rated at 98hp at max. power, and 92.5hp during cruise.
Tell me about the electrical system on the P206T
The P206T is fitted wit ha 14V electrical system supplied by 2 alternators (one for each engine), each capable of 40 amps.
This powers the glass cockpit, and the Rotax engine has a built-in generator on the left engine to recharge the ESP which sustains the avionics during engine restart in flight.
Tell me about anti/deicing system on the P206T
The P206T does not have any anti-icing system and is therefore not certified for operation into known icing conditions.
If icing inadvertently occurs, we must:
- Turn on pitot + carb heat
- Fly into an area clear of visible moisture
- Increase propellor RPM to prevent ice build-up
- Continuously move the control surfaces to prevent locking
What is the clearway?
An area beyond the paved runway that is clear of obstacles where an aircraft can make a portion of its initial climb to its screen height.
What’s screen-height?
The minimum height that must be achieved before the end of the clearway, should an engine failure occur after take-off.
Jet - 35ft, or 15ft if the runway is wet
Prop - 50ft
Explain lift to someone who knows nothing about flying?
Lift is the phenomenon generated by an aerofoil due to pressure differences. A wing is cambered on the top and flat on the bottom which means that air on the top of the wing has to travel faster, reducing its pressure. The air beneath the wing now has a higher pressure, and due to the pressure gradient, the higher pressure pushes the wing upwards, creating lift.
What is Dutch roll?
Dutch rolls is an oscillatory instability around the longitudinal axis, usually associated with swept wing aircraft.
In a yaw, the outer wing travels faster, increasing its airflow and generates more lift, while the inner wing travels slower and generates less lift. It gets to a point where the outer wing exceeds its critical AoA, causing it to lose all of its lift, creating a yaw in the opposite direction - this cycle is repeated continuously.
Dutch roll is more likely to occur at:
- High AoA
- High altitudes
- Low IAS
Recovery:
- Descend, slow down, opposite aileron
What is critical angle of Attack?
The angle which produces the maximum lift coefficient, and when exceeded, airflow on the wing begins to separate, causing a stall.
What is mach buffet?
High speed buffet when close to Mcrit due to airflow separation on the wing caused by shockwaves when the airflow reaches LSS.
What is a mach trimmer?
Artificially corrects for Mach tuck by sensing the aircraft’s speed and signaling an upward movement on the elevator to maintain the AC’s pitch attitude.
What is the difference between IAS/CAS/EAS/TAS?
CAS = IAS corrected for instrument error EAS = CAS corrected for compressibility TAS = EAS corrected for density
What does the zero fuel weight include?
Total weight of the aircraft and all its contents including payload, minus the weight of any usable fuel.
What errors do NDB suffer from?
- Night effect: The ionosphere reflects signals back to the Earth, causing fluctuations
- Terrain effect: High terrain can reflect radio waves, giving erroneous readings
- Station interference: Due to congestion of stations in the LF/MF bands, there’s a possibility of interference from stations on or near the same frequency
- Thunderstorm error: Areas of high electrical activity can cause the ADF needle to deflect towards it rather than the station itself
What is Radiation/Advection fog?
Radiation fog: When the surface loses heat to the atmosphere by radiation, cooling the surface. The moist humid air above it also starts to cool, and when the temperature falls below the dewpoint, fog forms.
Advection fog: Forms when a warm, moist airmass flows over a colder surface, cooling the airmass and reducing its temperature to below dewpoint, creating fog.
What is freezing rain?
Precipitation that exists in supercooled liqiuid form below 0 degrees and freezes on contact with surfaces that are also <0 degrees.
(Supercooled water droplets that freeze on impact with objects they encounter)
Differences between freezing rain and sleet.
Freezing rain occurs when the air layer is so thin that the droplets don’t have enough time to freeze (Supercooled water droplets that freeze on impact with objects they encounter).
Sleet is precipitation that freezes on the way down which means that it’s less likely to stick to surfaces or cause ice build-up.
Clear ice - what is it? Is it dangerous?
Large supercooled water droplets that do not freeze instantly, but freeze gradually and smoothly across a surface, making it difficult to detect and harder to remove due to its thickness.
Fuel calculations: what is included (Trip, Final Reserve, Alternate, Contingency)
Trip: SID, cruise, STAR, approach, landing
Final Reserve: 30 mins at 1500ft above alt/dest. AD
Alternate: MAP at dest, SID, cruise, STAR, approach, landing at alternate
Cotingency: 5% or total trip fuel or 5 mins holding at 1500ft above dest. AD in standard conditions
ETOPS
Extended Twin Operations
Where an operator is granted approval to operate twin-engined aircraft on routes where the aircraft is more than 60 minutes away from a suitable alt. AD in the event of an engine failure en-route.
Allows for a shorter flight path.
How many Boeings does Ryanair have?
409 NGs and 29 A320s
210 MAX on order ($22bn investment)
Planning to have 505 aircraft by Summer 2022
What is a sea breeze and how does it form?
Occurs on hot days where the land warms up quicker than the sea, causing the air above the land to heat and rise, increasing its pressure.
The pressure difference causes the air over the land to move to the sea, inducing an opposite pressure difference as the outflow of air gets cooler and denser, so it descends over the sea, increasing its pressure.
This then induces a flow of air from the sea to the land.
Swept wings: Advantages/disadvantages and how does it work?
Swept wings are found on most modern airliners and are used to delay the airflow over the wing from becoming supersonice by reducing the effective chordwise velocity.
Advantages:
- Higher cruise speeds/Mcrit
- Stability in turbulence (poor lift qualities means that it’s less responsive to updraughts compared to straight wing aircraft)
Disadvantages:
- Poor lift qualities
- Speed instablity
- Higher stall speed
- Wing tip stalling tendencies
Why is snow a problem?
- Snow build up on wings will reduce performance by increasing drag, increasing weight, increasing stall speed and reducing lift
- Blockages of pitot/static ports, navigation/radio aerials
- Increased T/O and LDG distances
- Ice build up on the engine intact can restrict airflow and reduce engine power
