Let’s pick this up right where the Rules of the Air leave off — Page 104, Lesson 166

Let’s pick this up right where the Rules of the Air leave off. I want to walk you through the pre-flight and in-flight duties that sit on the commander, then the hard limits on alcohol and drugs, and finally the minimum height rule. First, the pre-flight study. For all IFR flights — that’s every flight flown under Instrument Flight Rules — the commander must include a careful study of available current weather reports and forecasts. Notice the word current — you can’t rely on yesterday’s briefing. And this study isn’t just about the weather itself. You must take into consideration fuel requirements and an alternative course of action if the flight cannot be completed as planned. So the thought process is: what’s the weather doing, how much fuel does that demand, and what do I do if I can’t finish the flight as planned — that’s your alternate plan. Then the key authority point: the commander of an aeroplane has the final authority as to the disposition of the aircraft whilst in command. Disposition means how the aircraft is used, moved, and handled — and that authority is final, it rests with the commander alone. There’s a note attached to this that I want you to hold onto: The Rules of the Air may only be broken if absolutely necessary in the interests of flight safety. So the rules are not optional decoration — you break them only when flight safety genuinely demands it, and that’s the only justification. Now, section 6.10 — Intoxicating Liquor, Narcotics or Drugs. The rule is blunt: No person is to pilot an aircraft, or act as a flight crew member of an aircraft, whilst under the influence of intoxicating liquor, any narcotic or drug, by reason of which that person’s capacity to act is impaired. So the trigger is impairment — if the substance impairs your capacity to act, you’re prohibited from piloting or crewing. Here’s an important contrast. ICAO does not lay down any restrictions or maximum blood/alcohol levels for aircrew. ICAO leaves that blank. But JAR OPS-1 does — that’s the Joint Aviation Requirements for Operations, the European operating rules. Under JAR OPS-1, aircrew are not permitted to exercise the privileges of their licences with a blood/alcohol level exceeding 0.2 promille (20 mg/100 ml). Let me unpack that. Promille means parts per thousand — so 0.2 promille is 0.2 grams of alcohol per litre of blood. The parenthetical gives you the same limit in different units: 20 mg per 100 ml of blood. And to give you a sense of scale, that’s about one quarter of the UK driving limit. So the aviation limit is far stricter than the road limit. Then ICAO adds another layer: ICAO clearly states that no person may act as aircrew if he/she is under the effect of any psychotropic substance. A psychotropic substance is one that acts on the mind — affecting mood, perception, or consciousness. So even if a drug doesn’t show up as alcohol, if it’s psychotropic and you’re under its effect, you cannot act as aircrew. And then the professional expectation: As professional pilots, you are expected to behave in an adult manner commensurate with the responsibility placed on your shoulders concerning the safety of the passengers in your care. This is an onerous duty — heavy, burdensome — and if it is abused, it will result in the full force of the law being applied if you are found negligent in that duty. So the legal consequence is real and severe. Now section 6.11 — Minimum Heights, under General Rules. The rule: Except when necessary for take-off or landing, or except by permission of the appropriate authority, aircraft shall not be flown over the congested areas of cities, towns or settlements or over an open-air gathering of persons, unless at such a height as will permit, in the event of an emergency arising, a landing to be made without undue hazard to persons or property on the surface. Let me break that down. The exceptions are take-off, landing, or permission from the appropriate authority. Otherwise, over congested areas — cities, towns, settlements — or over an open-air gathering of people, you must fly at a height that, if an emergency happens, lets you land without undue hazard to persons or property on the surface. So the height is set by the emergency-landing requirement, not by a fixed number. And here’s the crucial clarification: No specific heights are mentioned in this rule, and this rule should not be confused with the minimum height rules for IFR or VFR. So this is a separate, general rule — it doesn’t give you a number, and it’s distinct from the specific IFR and VFR minimum height rules you’ll meet later. Finally, a terminology note: The term “aircraft level” is used generally to mean flight level, altitude, or height. So when you see “aircraft level” in the rules, it’s a catch-all covering all three ways of expressing vertical position — flight level, altitude, or height. Let me tie it together. The commander studies current weather, plans fuel and an alternate, and holds final authority over the aircraft. Alcohol and drugs are capped at 0.2 promille under JAR OPS-1, with no ICAO limit but a psychotropic-substance ban, and the duty is onerous with legal force behind it. And minimum heights over congested areas are set by the emergency-landing requirement, with no fixed figure, distinct from the IFR/VFR rules.