Five Things You Should Know About Takeoffs

To most people, a runway is simply a runway. We all know that an aircraft needs ample space to take off and land safely. Beyond that, the average passenger doesn’t know much about runways. However, there is much more to a runway than the length. The following details five things you can add to your repertoire if you need to make small talk with a pilot.

• Basic key factors. There are three key factors at play with any runway: the length, the current air temperature, and the altitude. Many people don’t realize that all of these factors are at play when airplane flights are scheduled. For example, typically flights leaving from Mexico City going to Europe leave late at night. With a high airport elevation and year round warm temperatures, planes function best during the coolest part of the day.

• Thrust rating. The thrust rating tells us how much power the take off produces to help the aircraft make its initial ascent. Once the plane has left the ground, the thrust is reduced for the majority of the flight. While the aircraft isn’t as powerful as it was when it took off, it gained considerable momentum, requiring a minimal thrust level for the duration of the flight. A pilot may boost the thrust if the plane needs to gain speed or increase its altitude.
• ISA rating. The ISA or International Standard Atmosphere rating tells us where the engine achieves optimal performance. Typically the rating is followed by a plus sign and a number. In simple terms, it tells us at what point in temperature, plus ISA, that the engine will perform as intended.

• Landing Distance Required (LDR) and Landing Distance Available (LDA). There are two data points that are used to determine how much distance a plane requires for landing. LDR is the amount of runway required for landing, and LDA is the runway length. LDR must always be less than LDA. Ideally the actual landing distance will be significantly below LDR to provide an ample safety buffer zone.
• Runway categories. ILS or Instrument Landing System is a ground system that assists pilots with landing airplanes safely. The three types of ILS are used to categorize runways as follows: CAT I, CAT II, CAT III, CAT IIIa, and CAT IIIb. Each category has a decision height and a runway visual height, both measured in feet. The decision height is the height at which the pilot must make a decision on a missed approach if the runway isn’t visible. The runway visual height is the minimum amount of visibility that a pilot must have while approaching a runway to make a safe landing.