From the Flight Deck

Winging in to a landing at Marshfield Municipal Airport from the west and looking out over Cape Cod Bay is always a breathtaking experience. Bright blue sky hovers over the deep blue sea in a view that never grows old. One of life’s charms is to sit back and gaze at such beauty while the pilots focus on bringing the aircraft in for another safe landing.

And one of the markings the pilots see that passengers might miss is the number that identifies this runway. In the photo at the top, it’s the number 6. Landing from the other direction, the runway number is 24.

So, why 6 and 24? (Or, 2-4 when spoken – the numerals are read individually.)

It’s actually a fairly simple, and universal, system.

But let’s first back up a bit.

Airport Pavement Maintenance System

Among its many responsibilities, the Massachusetts Department of Transportation’s Aeronautics Division provides and funds an Airport Pavement Maintenance System (APMS) program for public-use airports in Massachusetts.

“This is done usually every three to four years to not only improve the aesthetics of the airport pavement, but also to improve airport safety for the airport operator and for the general flying public who use the airport, as well,” explained Ben Garman, the airport’s assistant manager and part of the Shoreline Aviation team. Shoreline manages the airport for the town of Marshfield.

“The pavement maintenance program is split into three stages,” he said. “The first stage is to crack seal the runway and taxiway. Secondly, a seal coat is applied to the runway and the taxiway. And thirdly, the runway and taxiway markings are all cleaned and re-painted.”

Runway 6 before it is markings are repaired. Photo/Ben Garman

Runway 6 is renewed with its paint job. Photo/Ben Garman

The first two stages were conducted over the past few weeks. The third stage was just recently completed. Stantec performed the engineering, Indus handled the pavement work, and Hi-Lite spruced up the lettering.

“Although the airport may have to deal with temporary inconveniences throughout the duration of the pavement maintenance program,” Ben said, “the end result is well worth it, as it improves not only the longevity of the pavement surfaces, runways and taxiways, but it improves the safety of the airport for pilots, where all the markings are clearly visible, especially helping them during night operations.”

All the work is done to FAA guidelines. FAA Airport Marking Aid guidelines note that “airport pavement marking and signs provide information that is useful to a pilot during takeoff, landing and taxiing.” And that “uniformity in airport markings and signs from one airport to another enhances safety and improves efficiency.”

So – how to number a runway?

Marshfield’s runway runs more or less east and west, based on the directions of the prevailing winds. The idea is pilots want to take off and land into the wind (and that is a whole other topic). Actually, the approach to the Marshfield Airport runway from the west is a heading of 062 degrees magnetic (046 degrees true). And that is where we begin the creation of the runway numbers.

To arrive at a runway number, take the magnetic heading, round it off to the nearest 10 degrees (in this case 060) and then drop the final zero. That gives us 06, or just 6, for the runway number.

Coming in from over the water, the approach is 242 magnetic. Rounding off to the nearest zero gives us 240. Drop the zero, and you have runway 24.

Taxiway Charlie has a nice new look. Photo/Ben Garman

Other runway markings are important, too

“The runway centerline is identified by the white dashed markings down the center of the runway,” Ben explained. “Other runway markings include 1,000-foot markings that are white dashes every 1,000 feet down the runway. The displaced threshold is marked by the white arrows pointing towards the beginning of the runway where the runway numbers are. Aircraft can use this displaced threshold for takeoff but not for landing. The aircraft has to touch down after the displaced threshold.”

Larger airports might have parallel runways. Two parallel runways would be numbered with an added L (left) or R (right). Three parallel runways would include one with a C (center). Four or more parallel runways would use these three notations and then shift the number by one. So, you could have 6L, 6C, 6R and 7.

Looking back at the beginning of runway 24 prior to the work. Photo/Ben Garman

Runway 24 appears reborn after its marking repair. Photo/Ben Garman

There’s a good deal of basis for how things work around airports. FAA Airport Marking Aid guidelines note that “airport pavement marking and signs provide information that is useful to a pilot during takeoff, landing and taxiing.” And that “uniformity in airport markings and signs from one airport to another enhances safety and improves efficiency.”

With the major ramp reconstruction done last year, and now the runway upgrades, the airport is in great shape going forward.

“All of us here at KGHG would like to give a big thank you to our friends at MassDOT Aeronautics, Stantec, Indus, and Hi-Lite for keeping not only GHG but all the public-use airports in Massachusetts looking their best,” Ben said. “Thank you to all!”