ATPL Operational Procedures Questions

The risk of dynamic hydroplaning on a runway depends primarily on which factor?

• The depth of standing water on the runway
• The aircraft's total weight
• The strength of the headwind component
• The amount of speed remaining after lift-off

Explanation: Dynamic hydroplaning occurs when a wedge of standing water builds up faster than it can escape from under the tire, effectively lifting the tire off the runway surface - so the depth of standing water (relative to tire pressure/speed) is the dominant factor, more than aircraft weight.

Operational Procedures - Runway Contamination & Hydroplaning

For wake turbulence radar separation, when a heavy aircraft is following directly behind another heavy aircraft on approach to the same runway, the applicable minimum is generally about:

• 7.4 km (4 nm)
• 3.7 km (2 nm)
• 9.3 km (5 nm)
• 11.1 km (6 nm)

Explanation: Heavy-behind-heavy is the one wake-turbulence radar-separation case that uses a reduced 4 nm minimum, reflecting that both aircraft can tolerate somewhat more wake exposure than lighter aircraft following a heavy one, which instead need larger separations.

Operational Procedures - Wake Turbulence Separation Minima

Up until what point during a landing can a go-around generally still be initiated?

• At any time up until touchdown (and in some cases even after touchdown, if certified for it)
• Only before passing the outer marker
• Only above 1,000 ft above the runway
• Only if requested in advance from air traffic control

Explanation: A go-around remains an available option at any point up until touchdown - and some aircraft types are certified for a go-around initiated even after the main gear briefly touches down - reflecting that safety takes priority over completing a landing that isn't developing as expected.

Operational Procedures - Go-Around Decision

What is a de-icing/anti-icing fluid's 'holdover time' (HOT)?

• The estimated period during which the fluid is expected to prevent frost, ice, or snow from accumulating on the treated surfaces
• The maximum time the fluid can remain in its storage tank before it must be discarded
• The time it takes for the fluid to be fully absorbed into the airframe structure
• A fixed period that never varies regardless of the weather

Explanation: Holdover time is an estimated, condition-dependent window (varying with precipitation type, intensity, and temperature) during which applied de-icing/anti-icing fluid is expected to keep protected surfaces free of frozen contamination - once that time is exceeded, the protection can no longer be relied on and re-treatment or a fresh inspection is generally required before takeoff.

Operational Procedures - De-icing & Anti-icing Procedures

What is generally meant by an 'approach ban'?

• A regulatory rule preventing an aircraft from continuing an approach beyond a defined point when the reported visibility or RVR is below the minimum applicable to that approach
• A permanent prohibition on flying any instrument approach at a given aerodrome
• A rule that only applies to visual approaches, never instrument approaches
• A restriction that applies only to aircraft without an autopilot

Explanation: An approach ban prevents a flight from continuing an instrument approach past a specified point (commonly the outer marker or an equivalent position) if the reported visibility or RVR at the time is below the minimum required for that particular approach and aircraft/crew category, rather than continuing on the chance that conditions might improve by the time minima are reached.

Operational Procedures - Approach Ban

What is the general purpose of a Quick Reference Handbook (QRH)?

• To provide a quick-access reference to abnormal and emergency checklists during flight
• To provide the full aircraft flight manual in an abbreviated summary form only
• To list scheduled maintenance intervals for the aircraft
• To provide passenger service standards for cabin crew

Explanation: A QRH is organised for fast, reliable access to the checklists a crew needs when responding to an abnormal or emergency condition in flight, structured so that critical items can be found and followed quickly under time pressure, rather than searching through a much larger reference document.

Operational Procedures - Quick Reference Handbook

What is the general purpose of a pre-departure briefing between flight crew members before starting the take-off roll?

• To establish shared expectations about the planned departure, relevant procedures, and contingencies before the take-off begins
• To discuss matters entirely unrelated to the flight, as a way to relax before departure
• To replace the need for any written checklist
• To formally hand over control of the aircraft between pilots

Explanation: A pre-departure briefing lets the crew agree in advance on the planned departure procedure, relevant speeds and altitudes, and how they intend to handle foreseeable contingencies (such as an engine failure after V1) - so that if something does happen, the response has effectively already been discussed rather than being worked out for the first time under pressure.

Operational Procedures - Pre-Departure Briefing

Why are aircraft tires generally inflated with nitrogen rather than ordinary compressed air?

• Nitrogen is inert and dry, reducing the risk of an internal tire fire from heat/oxidation and avoiding the pressure fluctuations moisture in ordinary air could cause with temperature changes
• Nitrogen is heavier than air and therefore keeps the tire firmer
• Nitrogen improves the tire's grip on a wet runway
• Nitrogen is used purely because it is cheaper than compressed air

Explanation: Nitrogen is inert (won't support combustion) and essentially free of moisture, which reduces the risk of an internal tire fire or failure from heat generated during braking, and avoids the pressure fluctuations that trapped moisture in ordinary compressed air could otherwise cause as temperature changes.

Operational Procedures - Tires