What You May Not Know About Runways

 It’s said that a mile of highway will take you a mile, but a mile of runway will take you anywhere.

From the world’s shortest runways to runways over a mile above sea level, pilots need training to be prepared to execute nontraditional take-offs and landings.

What You May Not Know About Runways

Successful vs Rejected Takeoff

The takeoff speed required of an aircraft depends entirely on the type. Speed at takeoff is also determined by the condition of the runway, including its length, slope, and any road hazards. Did you know when calculating a takeoff, a pilot includes a “Plan B” in the event there’s a rejected takeoff? In the event of any technical difficulties with the aircraft, the pilot has a backup plan for aborting the takeoff and safely rerouting back to the gate. Keep reading for some more specifics on how a pilot gauges whether or not s/he can execute a successful take-off.

Types of Takeoff

Horizontal takeoff is dictated by V-speeds. Governed by aviation regulations, V-speeds refer to the data that has been collected regarding an individual aircraft’s needs for taking flight, maintaining flight, and landing.

  • V1 - When an aircraft reaches this speed on the runway, the plane should not consider rejecting takeoff.

  • V2 - At this speed, an aircraft can attempt a takeoff even if one engine has failed.

  • V2 Min - This is the safest minimum speed at which the aircraft can takeoff

  • V3 - Known as the speed at which flaps can be retracted

  • V4 - This is the optimal, steady climbing speed for an aircraft. An aircraft operating with both engines should reach V4 by 400 feet elevation.

  • V FTO - Final takeoff speed

  • V LOF - Lift-off speed

There are a number of other V-speeds, but these are the ones most commonly used when planning for takeoff.

Vertical takeoff allows an aircraft to take off without a runway. Angling the aircraft’s rotors and exhaust streams toward the ground allows the aircraft to create adequate lift and thrust to become airborne. 

How Fast Airplanes Are Going

Have you ever wondered exactly how fast the aircraft is going on the runway? It can be hard to tell when you’re in the cabin, busy securing your trays in an upright position and trying to stow your belongings under the seat in front of you. According to aerospaceweb.org, the average takeoff speed of large jetliners are as follows:

  • Boeing 737 - 150 mph takeoff speed

  • Boeing 757 - 160 mph takeoff speed

  • Airbus A320 - 170 mph takeoff speed

  • Airbus A340 - 180 mph takeoff speed

  • Boeing 747 - 180 mph takeoff speed

  • Concorde - 225 mph takeoff speed

How long it takes for an aircraft to reach these speeds varies, and can determine whether or not a plane can take off or land at certain airports.

Runway Lengths

The average runway length sits between 8,000 and 13,000 feet. Let’s take a look at some atypical runway lengths, compositions, and inclines.

Longest Runways

The longest military runway measures 7.41 miles and is located at Edwards Air Force Base in Muroc, California. This runway is actually a dry lake bed.

The longest commercial runway is at Qamdo Bamba Airport in Tibet, China. It’s 3.4 miles long (18,045 feet) and is 14,219 feet (2.6 miles) above sea level. Due to the size of the aircraft it services, and its elevation, the long runway is required for better takeoff and landing performance. No other commercial runway is located at a higher elevation.

Longest Ice Runway

Where else but in Antarctica would you find the longest ice runways in the world? The McMurdo Station in Antarctica is home to two ice runways, each measuring 10,000 feet in length. They were carved out of the frozen sea to allow large Air Force aircraft to bring cargo and crew to and from McMurdo.

Steepest Runway

The steepest runway in the world can be found at Courchevel International Airport in France. Measuring at 1,722 feet long, the angle of the runway is 18.5 degrees, which makes sense because this airport is in the French Alps. The runway was only 1,230 feet long until 1992 when it was extended for use during the Winter Olympics. IMDB credits this airport as a filming location for the 1997 James Bond film Tomorrow Never Dies

Shortest Commercial Runways in the World

For perspective, the average length of a driveway at a private residence is anywhere between 18 to 20 feet. Stack a couple dozen driveways end-to-end and you’re looking at viable aircraft runways.

Juancho E Yrausquin Airport

Although the runway at Courchevel is rather short, it’s still not considered the shortest commercial runway in the world. That title goes to a runway at Juancho E Yrausquin Airport on the Dutch Caribbean island Saba. This runway measures 1,312 feet and is surrounded by drop-offs on three sides.

Heligoland Airport

Another contender for the shortest runway in the world is one at Heligoland Airport in Germany. Located on Dune Island in the North Sea, the runway was initially 1,312 feet. In 2006 the runway was extended to 1,575 feet per European Union regulations for commercial aircraft.

Tenzing-Hillary Airport

A runway at Tenzing-Hillary Airport measuring 1,729 feet comes in at the third shortest in the world. It services many climbers heading to Mount Everest in Nepal, and only services small, fixed-wing aircraft and helicopters. In addition to being one of the shortest runways, this is also the 37th highest runway in the world, topping out at 9,101.05 feet (just over 1.7 miles) above sea level.

John A. Osborne Airport

Not only is a runway at John A Osborne Airport one of the shortest commercial landing strips in the world, but there’s a public road running underneath it. Located on the island of Montserrat in the Caribbean, this runway features a short tunnel underneath, allowing public access.

Scariest Runways in the World

For some of us, any airplane landing is a scary landing until we’ve come to a complete stop and have exited the aircraft. But did you know there are airports with such technical landings that only a handful of pilots have the necessary training to fly in and out?

Toncontin Airport

Located between mountains in Honduras, this airport requires pilots to make tight maneuvers in order to approach the runway. Aircraft also have to contend with inclement weather in this tropical location.

Paro Airport

Bhutan only allows 17 pilots to land on its Paro Airport runway. Due to its location between the mountains, flights are only allowed to operate in daylight. There is a 45-degree angle approach required before leveling out to land on the 6,500-foot runway.

Wellington Internation Airport

This New Zealand airport features a runway that has water at both ends. It was first extended in 1972, and Wellington City Council has been advocating for another extension since 2015. They hope to keep up with demand by lengthening the runway to accommodate both Boeing B787s and Airbus A350s.

Princess Juliana Internation Airport

No big deal, but this airport runway has a beach at one end. This means beachgoers get blasted with wind and engine noise when a plane takes off or lands on Saint Maarten. 

Gisborne Airport

Speaking of runway obstructions, this New Zealand airport has three runways that are unpaved and grassy. If you think that’s scary, the main runway at Gisborne has an active railway crossing. Yes, a freight train crosses the airplane runway.

With so many factors affecting the safety of take-offs and landings, it’s important to have a skilled pilot with hours of flight simulator and practical training under his cap. You never know when you’ll have to make a landing in the Alps, next to a beach, or after letting a train cross.

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