Comments about technological history, system fractures, and human resilience from James R. Chiles, the author of Inviting Disaster: Lessons from the Edge of Technology (HarperBusiness 2001; paperback 2002) and The God Machine: From Boomerangs to Black Hawks, the Story of the Helicopter (Random House, 2007, paperback 2008)

Thursday, July 21, 2011

The Billion-Dollar Branch: From flashover to blackout

Power blackouts begin with a single triggering event, like relays failing, or a heat wave that causes a transformer to explode, or a key power plant going down. These are single-point failures and usually don't lead to monster blackouts ... unless they're helped along by more failures, errors, and missed signals.

Trees that have grown too close to high-voltage lines (called "grow-ins" by the industry) are a common contributing cause, because these can lead to massive short circuits. The risk escalates during extreme weather events. Prevention of grow-ins costs billions of dollars every year.
Flashovers from powerlines to trees were a contributing cause of the August 14, 2003, Northeast Blackout. It started about noon, with a monitoring tool called a state estimator being accidentally left off line. This, along with a previously unknown software glitch in an alarm system (called a "race condition"), combined to reduce the operators' awareness of what was about to happen. At 1:30 pm, FirstEnergy's Eastlake, OH, generating station went off line. This redirected the flow of power around the region and beginning at 2 pm, caused high-voltage lines in three areas to overheat, soften, and sag toward tree branches below. Flashovers followed when the electricity arced to the tree, then to the ground. The huge flow of current caused protective relays to trip and each line went out of service in turn. These events set up a positive feedback loop (a bad one) that progressively put more strain on the system. Other problems followed and two hours after the first tree flashover, the blackout was fully underway, flicking off the lights for 55 million people. 

Why not trim every branch as soon as it poses a hazard? There's always room for improvement, and more assiduous branch-lopping was a key recommendation from the 2003 blackout lessons-learned reports. But nationwide there's almost 180,000 miles of high-voltage right-of-way, and it's not possible to know and respond to every hazard. That's because the problem is dynamic. Lines sway; trees sway and fall over. Branches grow toward the right of way, since there's more sunlight there.

Winter poses its own problems; here's my last post on the southwestern US freeze-out in early February, which set off a wave of generator outages and rolling blackouts across Texas.

Saturday, July 16, 2011

Empire State, Airships, and That World of Tomorrow

The NY Times ran this piece by Edward Rothstein about a history exhibit on the 80th floor of the Empire State Building.

This post is to add background to a line in the article:  "The walkway circles around the building’s narrow spire, which, in 1930, was envisioned as a mooring mast for dirigibles; as it turned out, only King Kong ever reliably used it for support."

Airships did stop by, but never for a passenger operation. The longest visit, by Goodyear's Enterprise, was a very brief publicity stunt. And it didn't look like this:
That was an artist's paste-up, done for the mooring mast's publicity campaign. For those curious about our early romance with gasbags and rooftops, here's an excerpt from my article "Hindenpunk," printed in the Winter 2010 issue of Invention&Technology magazine:

"How close did real airships actually come to shuttling passengers from building to building? In 1903 the Brazilian flier Alberto Santos-Dumont used his compact, gasoline-powered airship La Baladeuse to commute between Paris and the suburbs, trying it off to iron balconies while visiting. Airships dropped off passengers atop roofs in Akron and Cleveland. In 1929 an Army blimp rushed Sen. Hiram Bingham from an army base in Virginia to the steps of the Capitol, when he was was short of time. A Navy airship once sidled up to the National Bank of Tulsa's skyscraper. But none of these one-off events would muster even a footnote had the Empire State come through.

Talk of the Empire State's mast – what mastermind John J. Raskob called its hat – first appeared in the newspapers on December 11, 1929, following a press conference by ex-governor Alfred E. Smith. Citing the imminence of transoceanic airship routes, Smith said the mast and its speedy elevators would allow disembarking passengers to step onto Fifth Avenue just seven minutes after the airship made landfall. He didn't need to add that the mast's main job was to steal attention from the rival Chrysler Building. Better yet, it rode into a wave of international enthusiasm raised by Graf Zeppelin's round-the-world voyage.

Though the mast's extra cost (somewhere north of $100,000) was never offset by a dime in passenger fees, it yield a PR bonanza in “world's highest” stories. Luminaries including Ogden Nash, James Thurber, and Lewis Mumford wrote about it. Whenever interest flagged, publicists Amy Vanderbilt and Josef Israels drummed another airship event, each time snarling midtown traffic for hours. That included bringing airships to buzz the mast for newsreel cameras, luring the Goodyear blimp Enterprise over for a three-minute visit, and the inexplicable delivery by airship of a bundle of old newspapers from the roof of the New York Journal-American Building.

But no dirigible captain staked his life and career on a meeting with the mast. Readers may recall a visually striking motion picture released in 2004, Sky Captain and the World of Tomorrow. In the opening scene, the dirigible Hindenburg III pulls up to the Empire State's pinnacle on a snowy night. A man standing on the building's parapet catches a rope from the craft and holds tight while the airship drops a boarding ramp from the nose to the balcony. Seem reasonable? That's how motor boats and fishing skiffs pull up at a dock. 

But a speedboat isn't 800 feet long and doesn't go on a rampage if untethered during gusty winds. Hugo Eckener, the greatest airship pilot of the age, laughed when a reporter asked about bringing his Graf Zeppelin to the Empire State. He noted that many spiky buildings nearby turbled the winds and said with Teutonic politeness that he would not proceed without “many, many experiments” beforehand.

The job of a mooring mast (one early model of which still exists, in Recife, Brazil) is to draw an airship nose first into a secure locking mechanism. Empire State planners based their designs chiefly on two masts. The first was a tall land-based structure at St. Hubert, Canada, erected for the visit of the airship R-100 in August 1930 (and never used again). Drawings of the Empire State's mast show a very similar mechanical connection between mast and airship. Hubert was a “high mast,” 210 feet tall, which held airships so far off the ground that passengers could only come and go through a nose-mounted gangway that linked to a circular railing near the top of the mast. The Empire State would have relied on the same gangway arrangement to get passengers out of the ship.

But bringing mast and airship together was going to be tricky in a downtown setting, for several reasons, one being that ground crews couldn't run around the streets of Manhattan, gathering lines dropped from airships a half mile up then feeding them into winches, in the way that crews could hustle across the grass at conventional dirigible stations. (Note to fantasy writers: don't forget the port and starboard yaw lines when mooring your dirigibles. Without yaw lines, a big airship will veer and surge when approaching a mast and, quite likely, crash into it.)

Since the mast on the Empire State was a quarter-mile high, an arriving airship would have to drop its three lines almost on the mooring crew's heads. This was the reason that the Navy recommended a look at the stern-mounted mast on the airship tender USS Patoka, a converted oil tanker.

The Patoka's crew came up with a streamlined mooring method in which arriving airships like the Los Angeles dragged a grappling hook across the ship's stern. This allowed the Patoka to connect its winches to the airship and avoided the need for sending out motor launches to retrieve lines from the water. A unique feature of the Patoka's mast was its two side-mounted “yaw booms,” each 100 feet long, making an inverted “T” when deployed. Engineers of the Empire State extended the wall columns at the top of the building for mounting these heavy booms. Had it carried through, the skyscraper would have taken on a distinctly nautical look.

Considering the architects' close attention to the workings of other masts, I'd say builders of the Empire State made more than a sham effort through 1931. But no experts came up with a way to control airships in such a wickedly drafty setting. In 1939, seven years after Manhattan got over its case of airship fever, The New Yorker commented that nobody in the building management even wanted to talk about it."

Monday, July 11, 2011

Cars Below, Copters Above: That's Carmageddon

Winding up a research trip to LA and pulling up at LAX, Los Angeles International Airport, I saw a sign for the heliport, designated P4. It occupies the top of a concrete parking garage. If you happen to have the money to own or rent a helicopter, access to LAX doesn't get much easier, particularly this coming weekend, when Carmageddon does LA. 

First, to Carmageddon, then the remarkably obscure heliport at LAX.

Los Angelenos live and die by their car-borne freedom, so the upcoming 53-hour closure of ten miles of the Four-Oh-Five (aka Interstate 405, or the San Diego Freeway) has sent an earthquake-like shudder through the driving population. 

Why? The 405 is one of the busiest highways in the country ... a critical link in a no-slack grid. It's the shortest path for travelers from coastal communities up north to get across the basin to San Diego. For people living in the San Fernando Valley the 405 is the shortest way to West LA or LAX airport. 

Within the first four minutes of getting into my rental car on Thursday, I heard five references to Carmageddon: from the rental attendant, and on two different radio stations. And that was more than a week ahead of C-Hour late Friday night, when crews will start closing the interstate until Monday morning.

There will be 24/7 work to add a new high-occupancy-vehicle lane, demolition of bridge sections, seismic refits, and other odds and ends. Is it worth the money and hassle? Skeptics like the LA Weekly predict that in a short time the 405 will be back to its sluggardly pace, as drivers who formerly had avoided the freeway begin using the HOV lane.

Traffic-watchers suggest that drivers flee the city before C-Hour or leave the car in the garage. One reason is Sepulveda Pass, where drivers will be shunted onto side streets like Sepulveda Boulevard, the Pacific Coast Highway (routinely crowded each summer weekend, even at the best of times), or steep, winding, two-lane canyon roads, where drivers can participate in traffic jams that could rival those that ring Beijing. Once stuck a mile or two down a canyon road, there will be no way to change one's mind, No Exit.

While outsiders may think all of Greater LA as one big smoggy basin, many commuters live to the northwest, in the San Fernando Valley. The problem is a set of ridges and low mountains that separate the San Fernando area with the LA Basin, and choke down the traffic routes.

In any case the most visible aspect of work during Carmageddon will be 53-hour demolition of the south portion of the historic Mulholland Bridge. The north part will come down a year from now. Here's a bridge photo:
Construction of the replacement bridge will be much slower. While it's possible to pre-build a new highway overpass nearby, and then use wheeled, heavy-transport platforms to roll the sections into place, that's not the plan here. (Here's a link to a video showing a rapid-build bridge project in Massachusetts.)

Thus, thinking of the car-chaos to come, I was interested to see the sign to the LAX P4 Heliport.

In 2006 I rode into this heliport with chopper news-reporter pilot Larry Welk (technically, Lawrence Welk III, grandson of Lawrence Welk). I was researching my copter book, The God Machine

Larry wanted to make the point to me that helicopters can blaze their own path. It was surprising to me that with just a few radio calls to the tower, and a few tweaks to the cyclic and collective, Larry was able to breeze his AStar onto the heliport, which is smack in the middle of the airport complex. Also aboard was ace camera operator Gil Leyvas. 

Larry showed me a few tips, then took off and headed out over the coast to resume the prowl for news. 

Despite the high hopes of helicopter enthusiasts of the early 1960s, who expected heliports to be common feature of major buildings in all major cities, LAX's P4 heliport is one of the very few public heliports in the LA Basin. It survived a 2001 attempt to close it and convert the space to car-parking.

While no other helicopters were parked when I dropped in with Larry and Gil, helicopter parking spots at LAX may see a spike in usage in the next few days, given that street access into and out of the airport will be problematic. Affluent flyers can buy rides direct to LAX from locations like the new Maguire Heliport atop a parking garage in downtown LA, or from the Van Nuys Airport. 

Los Angeles heli-history note: President John F. Kennedy flew into the Beverly Hilton's helipad during his 1963 visit to LA, and the Beatles used a pad at the Millennium Hilton in 1964. Disneyland in Anaheim once had its own ground-level heliport, which Los Angeles Airways used for a commuting service that ran until 1971.

Here's a link to locating the Disneyland heliport, on the Abandoned and Little Known Airports site. 

Sunday, July 3, 2011

Night Lights on the Prairie

Driving through Iowa last week, we saw a major thunderstorm develop to the west, cross our line of travel, and head east. 

The first sign was a major anvil cloud, dozens of miles long, building to the west. We noted the portents, checked NOAA radar via iPhone, and sought shelter at a rest area at Lake Mills, Iowa, where we saw this shelf cloud:
After waiting in the concrete building for the chilly winds behind the front to blow over (literally ... the gusts toppled newspaper stands at our location and knocked down trees elsewhere) we continued north and angled for lightning photos on the way as the front moved east. 

I used exposures of two to three seconds, aiming out the passenger window. Such photos tend to be blurry, like this image of phantom trees on phantom hills:

One good thing about time exposures from a moving, handheld camera is that multiple bolts -- leaders and return strokes -- can be imaged separately in the same picture, even though they follow the same ionized channel in the atmosphere. Check out the bolt on the left: it's composed of at least four baby bolts.

Next is an illustration of how a single lightning blast can act like a big flashbulb. Note how the fence posts and grasses are sharp and clear, though it was pitch dark. With our car moving at sixty miles an hour, any normal lighting would have blurred the scene. Observers at the predawn Trinity atomic test at Alamogordo, NM, in 1945 noted the same phenomenon at ignition: for a split second, one said later, he felt he could see every tree and rock for miles.
We got off at an exit to catch this bolt-lit sheet of clouds:
Finally, here's a cloud-to-cloud bolt, spanning 40 degrees of sky.