Science

Moving Stairs and Other Investigations

Answering questions about Stuyvesant’s escalators and the building’s construction.

Reading Time: 5 minutes

Stuyvesant is a very special school, not only because of its academics, but also because of its building. The building tends to be overlooked, but its quirks make it unique for a New York City public high school. Not only is it located right on the Hudson River, but it is also a massive 10 story building with escalators. There is a lot to explore on those 10 floors, so we reached out to the student body for questions about their school, and answered a selection below.


  1. Were there any special considerations for Stuyvesant’s architecture due to its location?

Nearly all of Battery Park City was built on land extended from the natural Manhattan island. The development of the area was based on a plan from the ‘60s and used material excavated from when the World Trade Center was built. Further inland, the old piers in the area were replaced with this material as well. Cellular cofferdams, dams made of interconnected steel boundaries that are filled with sand to withstand water pressure, were built on the border of the new land. Building developments on top of the newly constructed land required driving piles down to the bedrock for support.

At the time, the building was the first built directly by the Battery Park City Authority (BPCA), the administrative body in charge of planning and regulating the area. This means the building follows BPCA’s guidelines to a tee; it has a two or three-story stone base and an earth-toned façade with green detailing.


2. When is it faster to take the escalator instead of the stairs?

Walking up the stairs is not fun for students—especially when they are lugging around 10-pound backpacks—but it can be faster than riding the escalators. To prove this assertion, we must examine whether it is more efficient to take the stairs or the escalator depending on the number of floors being traveled.

The data collected represents the time it took us to travel around Stuyvesant, but students climb stairs carrying different loads and in different physical shapes. Students also differ greatly in how much they are willing to tire themselves while going upstairs, as well as whether they wish to use escalators. Times can also vary with different levels of crowding in staircases and escalators. However, it is still valuable to examine the data, the results of which can be roughly applied to the entire student body.

According to our calculations, it takes 38 seconds to move up a two-story escalator standing in place, and roughly 26 seconds to walk down an empty hallway to reach the next escalator. This means that it takes one minute and four seconds to travel every two floors.

When timing our stair-climbing, we began on the second floor, as this is the first floor with escalators. We ended on the ninth floor, the last floor with escalators. We climbed the stairs at a walking pace and accounted for any time we used to catch our breath.

We recorded that climbing the first flight of stairs with a backpack of around 12 pounds takes approximately 19 seconds. Due to increasing exhaustion, subsequent floors each took a few seconds longer to traverse. The second flight took 21 seconds, the third took 23 seconds, the fourth took 25 seconds, the fifth took 28 seconds, the sixth took 30 seconds, and the seventh took 33 seconds. As flights for different floors are not separated by halls, no additional time was considered for that distance.

Looking exclusively at these results, it would appear that for us, and likely for many others, it is quicker to take the stairs regardless of the number of floors traveled.

Here is a table summarizing our observations:


3. How much faster would hallway traffic move if students got on the first escalator step available instead of the second or third?

Escalator etiquette is a tricky thing—it is uncomfortable to stand too close to someone or their backpack. Thus, Stuyvesant students often wait for one or two stairs to pass before boarding an escalator. To determine how much more efficient Stuyvesant escalator usage could be, we observed the frequently crowded four to six escalator.

Seconds after the passing period began, escalator riders moved slowly. As traffic quickly picked up, the group fanned out around the entrance. During the first minute of the passing period, 43 students got on the escalator. During that time, 22 of them waited for one or more stairs to pass before getting on, and 24 students left one or more steps between them and the person immediately in front. Even if they got on right away, many students did not walk up to close the gap between them and the next person.

Based on the first minute of passing, an estimate for the number of people riding a given escalator per passing time is 215. About half of them are predicted to either skip steps or leave stairs in between themselves and others. Despite each stair taking a fraction of a second to move out, most people’s pauses were between one and two seconds long. Thus, within a given passing time, an average of 2.5 minutes is wasted by people’s hesitation. In reality, this number is lower, perhaps 1.5 minutes, because we observed the rate of students riding the escalator increase—and the number of people pausing decrease—as the next period approached and more people piled onto the escalator. Still, assuming there is a steady supply of students, the equivalent of 1.5 minutes worth of students would be able to get on the escalator if nobody hesitated, equating to 65 extra students.

However, Stuyvesant escalators could be even more efficient. If at least 24 steps are being skipped per minute, at least 120 students lose a spot on the escalator each passing period. Considering that each step can hold two students, that number is 240 students. With every other step being occupied by one or two students, it would be possible for 455 students to ride the escalator if everyone climbed up behind the person in front of them, though by that point it might be a question of how many students are available in the first place.

Currently, traffic on an escalator is about 43 students per minute, but could be above 60 students per minute if nobody paused before getting on. However, by reducing the amount of skipped or half-full stairs, that number could theoretically reach 90 students per minute, or even more. If Stuyvesant students move more efficiently, at least twice the number of people would be able to ride the escalator, and the surrounding crowd would move twice as quickly.