Audio, e-book, Print, & Large Print
And a great charity anthology including Miranda’s 1st investigation story, Galaxy
In February, my wife and I went out with the Massachusetts Audubon Society to two lovely spots: Incinerator Road and the Wastewater Treatment Plant in the, slightly sad, old mill town of Lawrence, Massachusetts. Incinerator Road actually leads to a ball field perched atop a hill that offers a sweeping view of town and the Merrimack River. The busy little airport is perched just over the ridge, and small private planes were zipping aloft for a sunset flight the chill but beautifully clear evening.
There wasn’t much to see at first. The occasional crow flitted by, but the Audubon guide promised us there was more to come.
It only happens in the winter. Crows will gather in staging groups in this area. And then, as a single mass, all of them will go aloft and move to the final resting spot where they will spend the night.
So we watched and waited. The groups grew. The last photos I was able to get before it became too dark are the three below. These photos were mere seconds apart. The same section of river, just different segments of the great stream of crows flying above its waters.
Over the next, rather cold, hour, this stream was constant: a massive group of 2-300 crows would pass by, a five-minute pause, and another two groups would wing in. And that was just from the south. We could see them coming downriver as well in the far distance.
They come from all over this section of Massachusetts. For at least 20 or 30 miles around, the crows all fly to the river and then follow it to this area. They’ve been doing it for decades that we know of.
We then shifted to the riverside wastewater treatment plant at the very tip of N. Main St., thankfully odor free. It was now too dark to photograph, but we were at the very southern edge of a massive gathering spot. The crows were so thick that we kept wondering why the branches above us weren’t breaking.
Then at full dark, just as the guide had predicted, they swirled aloft en masse. Venus was clear in the sky and Orion (discussed back in February in NerdGuy #6: Orion and Not Orion) was showing his changing form. For five minutes, the night was so thick with crows that the last of the dark evening blue was blotted out. In flights of thousands they crossed the river to perch on trees directly across the river from us on a little no man’s land between a freeway on ramp and the river.
The “why” is a puzzle. They’re big birds, so they don’t need to huddle for warmth in most weather as the little birds do. Some of it is for protection from owls and such. But why not in groups of a thousand or so closer to home? No, some twenty thousand of them come here every night for the winter months. We’re seeking grant money to tag them and track where they go during all of the spring, summer, and fall.
These big night groupings happen all over. But for dozens of square miles around, perhaps hundreds, in the winter they’re roosted in the trees along the Merrimack River in Lawrence, Massachusetts.
Before we talk flight levels, we need to talk about one of the great peculiarities of flying. This is true worldwide and for a couple of bizarre reasons.
As I often rail against in my stories, the US is the very last country in the world to use the English standards of measurement. One major reason for this is that long ago, just as metrication began, the car lobby convinced Congress to pass a law. To avoid having to recalibrate so many things on American automobiles, the law states that federal funds may not be used to change highway signs from English to metric nor can states be forced to do so. (Federal Highway Act of 1976)
This effectively halted a planned multi-year roll-out through areas of our lives in the US. This grinding halt has now left us with 2 liters of Coke, 750ml of whiskey, but a 12-ounce beer. And forty years on, there are few other signs of the planned change.
Some few countries have converted to metric flight over their territories. China, North Korea, and five countries in SW Asia. One of which, Turkmenistan, uses meters near the surface, but English-based flight levels above 21,000′. For a while Russia flew in metric, but they switched back in 2011.
This original plan, I’m sure implemented by the US and the British Empire in the early days of flight, was adopted worldwide. And to get away from it, we really need to all change at once.
Flight below 18,000 feet (in most countries) is very different from flight above that.
At lower altitudes, pressure rules. There is a little dial on an airplane’s altimeter (lower left in the diagram below), that allows the pilot to dial in the pressure (little window on the right in inches of mercury), and read their altitude above sea level (even if they’re flying over Switzerland–that way everyone is calibrated the same).
The little pressure dial is critical because a high- or low-pressure weather system can change your displayed altitude drastically. So everyone must stay in sync.
Naming a flight level is easy; knock off the last two zeros as irrelevant. 15,000′ becomes FL150 (read as Flight Level One-five-zero). In metric, they always have to add the word “meters” to avoid confusion. However, just to be more awkward, they have to read out the two zeros (or say something like “four thousand five hundred meters”) because no one say Flight Level Four-five hectometers.
Above 18,000′ everyone uses the same pressure setting of 29.92′ of mercury (or the metric equivalent pressure of 1013.25 hPa [hectoPascals]). This makes it so that they’re all flying on a common level, once they’re high enough that they don’t really care about much other than the Himalayas. So FL210 may not be at 21,000′, but it will be exactly the same altitude for everyone flying at that altitude.
This is the fun bit you can use to understand the pilot’s announcements a little better on your next plane flight: Flight Levels have directions.
Eastbound flights fly at an odd number of thousands of feet. Westbound flights at an even number. This provides a thousand feet of vertical separation for any planes going in generally opposite directions. So the next time a pilot announces, “We’ve been cleared to climb to our cruising altitude of 36,000 feet”, you’ll know that you’re headed west.
Actually, you’ll never hear that, unless your pilot is drunk.
Why? Because above 31,000′ it was decided that 1,000′ wasn’t enough separation, so they jump to 2,000′ separations. The levels go like this:
Just to add to the fun, countries with predominantly N/S routes will actually twist this to be North-South rather than East-West: New Zealand, France, Italy, and Portugal. (And you thought flying was easy. This is all just about how high to fly!)
In my upcoming book Condor, it creates conversations like this one:
Jon looked around for how to explain himself to the others. “Miranda, stand up and hold out your hand. It’s now an airplane flying at thirty-nine thousand feet.”
“Which is my nose?”
She twisted around and faced the other end of the parked airplane’s narrow cabin as she held up her hand, palm down.
“What are you doing?”
“Flight level three-nine-zero is for westbound traffic. I’m pointing the nose of my hypothetical aircraft west.”
He noted the direction of the late afternoon sun slanting through the windows.
“Okay, flight level four-three-zero.”
She glanced over her shoulder at him. “Lizzy had said that the Russians would most likely be using an AN-124 Condor for transport.”
“So you mentioned. Your point?”
Then he knew what she was going to say. They ended up speaking in unison.
“Service ceiling of thirty-nine thousand feet.”
“Flight level three-seven-thousand feet, please.”
She turned around and aimed her fingertips at him with her palm still down, lowering her hand slightly to represent the change in altitude as she made the turn. She made him want to laugh aloud. But with the way Holly was watching him… He decided that cautious professionalism was a far better choice.
Hope you join me for nerding out on March 10th with Condor!
Five fire towers.
Five fire seasons.
Five stories of true love found while watching for wildfire.
Collected together for the first time, these heart-warming tales are the perfect antidote to a cold winter’s night. Includes exclusive author introductions to every story.