What Is a Taxiway?
If you’ve ever stared out the airplane window while slowly driving across the airfield and thought, “What exactly are we doing right now?” you were probably on a taxiway. It’s not the runway. It’s not the gate. It’s the in-between road that gets airplanes where they need to go, and it’s a whole world of rules, markings, lights, and safety zones that most people never think about.
So let’s break it down. Taxiways, from the centerline to the edge lights, from the paint to the pavement, and why they matter.
First: What Is a Taxiway?
A taxiway is a designated path for aircraft to move while on the ground. Planes use taxiways to get between runways, ramps, gates, cargo facilities, hangars, you name it. They don’t take off or land on them, but they do spend a lot of time on them.
At CMH, we have dozens of taxiways. Some are full length routes like Taxiway Echo, which runs parallel to the runway. Others are smaller connectors like Echo 3, which link main taxiways to the runway or apron. Echo gets you around the airport. Echo 3 gets you into position. Think of it like a freeway and an exit ramp. Echo is the freeway. Echo 3 is the ramp that gets you to the runway.
How Are Taxiways Named?
Taxiways follow FAA naming standards. They’re labeled with letters, and if there are multiple offshoots, they get a number too. The letters usually start from south to north, and the numbers increase from west to east. That’s how it works at CMH and most airports.
So Alpha is the southernmost taxiway. A1 is farther west, and A6 is farther east. This system helps everyone, pilots, ground controllers, and ops teams, speak the same language.
Runways vs Taxiways
Runways and taxiways have different jobs:
Runways are for taking off and landing
Taxiways are for getting from point A to B while still on the ground
Runways are labeled based on their magnetic heading. That just means the direction the runway points on a compass. Runway 28L at CMH faces 280 degrees, which is roughly west. The opposite end, Runway 10R, faces 100 degrees, which is roughly east. The numbers are rounded to the nearest 10 and shortened to two digits.
If there are parallel runways, like we have at CMH, we add L and R for Left and Right. So we get 28L and 28R, 10L and 10R.
Taxiways don’t use numbers like that. They use letters and are painted differently.
Markings, Paint, and Glass Beads
Taxiway paint is yellow. Runway paint is white. That’s a quick visual to tell where you are.
Taxiway markings include:
Centerline: A solid yellow line, exactly 6 inches wide, to help the pilot stay centered. The centerline is the most important line on the taxiway. It’s what we use to measure and design every safety area around it.
Edge lines: Double yellow lines that show where the pavement ends or where the strength changes. These only appear if the area beyond the edge is not meant for aircraft.
Hold short lines: Two solid and two dashed lines that mark the boundary before a runway. These are like stop signs for pilots. They must stop and get clearance before crossing. If the plane crosses without permission, it could enter an active runway, which is extremely dangerous.
And yes, there are glass beads in the paint. When I worked in Airfield Maintenance, one of my jobs was dropping those beads into wet paint using a pressurized bead gun. They reflect light at night and in low visibility weather, making the markings shine when aircraft lights hit them. Without those beads, a centerline can basically disappear at night or in snow. With them, the lights bounce off the paint and help the pilot stay exactly where they need to be.
Lights: Blue, Green, and a Hint of Amber
Blue lights mark the taxiway edges
Green lights mark the taxiway centerline (on certain routes only)
Coming off a runway, there are lead off lights. These lights guide pilots from the runway onto the taxiway. They alternate green and amber, but the first two lights are always green. That tells the pilot they’re still on the runway. Once they hit amber, they know they’ve fully exited. These lights are especially helpful in low visibility conditions like fog or snow.
What’s a Taxilane?
A taxilane looks similar to a taxiway, but it’s not the same thing. You’ll find taxilanes around the gates, in cargo ramps, and by GA hangars. The key difference is this:
If there’s usable pavement beyond the edge line, it’s probably a taxilane.
Taxilanes aren’t typically controlled by ATC, which stands for Air Traffic Control. That’s the team in the tower giving instructions to pilots and vehicles. Taxilanes also aren’t designed to the same specs as taxiways. But they’re still critical for safe movement, especially in tight ramp areas.
TSA, TOFA, and Taxilane OFA
Here’s the part most people don’t see. The area around the taxiway is just as important as the taxiway itself. That’s where these three zones come in:
TSA (Taxiway Safety Area): The graded, cleared ground next to the taxiway that needs to be strong enough to support an aircraft if it veers off. Nothing should be parked here. No cones, no equipment, no people. It’s like the shoulder of the road for aircraft.
TOFA (Taxiway Object Free Area): The invisible safety bubble around the centerline that ensures aircraft wings don’t hit anything. Poles, signs, equipment, trucks. If the plane is on the centerline, it should have full wing clearance. These areas are calculated based on the wingspan of the aircraft.
Taxilane OFA (Object Free Area): Same idea, just applied to taxilanes. These are often tighter spaces, so the clearances are a bit smaller, but the purpose is the same. Safe, wingtip clear movement.
All three of these zones are measured from the centerline. That’s why paint matters. That’s why inspections matter. That’s why we fix things the moment they’re wrong.
Aircraft Groupings
Airports are designed based on what kind of aircraft operate there. The FAA has six Airplane Design Groups (ADG) based on wingspan and gear width:
Group I: Small GA planes
Group II: Small jets and turboprops
Group III: 737s and similar
Group IV: 757s and 767s — that’s most of CMH
Group V: 777s, 787s
Group VI: A380, 747 8 — that’s Rickenbacker (LCK)
The group determines how wide the taxiways need to be, how much clearance is required in the TOFA, and even how far apart the markings are spaced.
So Why Does Any of This Matter?
Taxiways seem simple. Pavement, paint, some lights. But when you’re moving 100000 pound planes with 156 foot wingspans just a few feet apart, there’s no room for error.
A faded line, a misplaced cone, or a light outage isn’t a small deal. It’s a safety hazard. Every marking, every inspection, every foot of clearance matters.
We check it. We recheck it. We fix it. And if you’re on the centerline, we’ve got you covered.
Eyes on the edge lights. We’ll see you out there.
Why I’m doing this
Partly because people keep asking me, “What do you do?” and I want to be able to point to something that actually shows it.
But mostly?
Because I don’t want to forget what I’m learning.
This job is crazy. It’s complicated. It’s full of nuance. You can work here for twenty years and still not know everything. And I don’t want the lessons to slip past me just because I didn’t take five minutes to write them down.
So this is my version of capturing it.
One post at a time. One story at a time. One lesson at a time.
If you’ve ever wondered what happens behind the jet bridge, out past the taxiway lights, or behind those giant “AUTHORIZED PERSONNEL ONLY” doors… you’re in the right place.
Let’s get to work.