Philip Greenspun’s Weblog

My friend Tom had to give a talk in Washington, D.C., and I wanted to see my brother’s new baby.  So we piled into the Cirrus SR20 on Tuesday and flew from Bedford to Gaithersburg (KGAI).  The trip down involved the usual East Coast flying-as-transportation hazards:  an airmet for icing conditions, layers of clouds allegedly up to 15,000′, an airmet for turbulence below 12,000′, surface winds gusting to 30 knots.  It turned out not to be so bad at 6000′, which we held right over the top of the JFK airport (nyc photo).  Winds aloft were over 50 knots in strength, but weren’t right on the nose, so the ground speed wasn’t reduced by more than 20 knots.  Just north of Atlantic City, New Jersey, we requested a climb to 8000′ to stay above of the bumpy clouds.  The Potomac Approach frequency, 128.7, that is used by low-altitude little airplane guys, was almost dead silent.  The Maryland/Virginia area typically has some of the calmest winds in the U.S. and the local pilots were apparently turned off by the winds.  When we landed on Runway 32, the wind was more or less straight down the runway at 20 knots gusting 27.  Tom wasn’t too impressed by my landing, which was made more difficult by the fact that the runway slopes away downhill just as you are trying to flare.  Despite a higher-than-normal approach speed of 80 knots and the downhill runway, we did not need all 4200′ and turned off at a taxiway about 2/3rds of the way down.

Tom’s Town Car pulled up to the side of the plane just as we were pulling back the mixture.  Just like the turbine crowd!  We were driven to the Four Points Sheraton at 12th and K, whose striped carpet looked as though it had been salvaged from a Holiday Inn circa 1970.  My room was small and smelled of smoke.  The $325/night price shocked me into thinking that inflation is hitting East Coast yuppie lifestyle items pretty hard.

After lunch, I walked over to the National Portrait Gallery and Smithsonian American Art Museum, colocated in the recently restored former headquarters of the U.S. Patent Office (web site for the building).  At 333,000 square feet, it was the largest office building in the U.S. when completed in 1868 (for comparison, 333,000 s.f. is 3-6X the size of the private houses being built by some contemporary American businessmen and movie stars).  The museum has refreshing hours for us computer programmers:  11:30 am to 7 pm.  The portrait collection includes mini-biographies next to each portrait, which makes for an educational visit.  Lots of great Hudson River School and newer American art as well as creative folk art.  Photos:

• map of U.S. in neon and TV monitors (just our route)
• storage space
• gallery space

Dinner was at my brother’s place in Maryland, where his 5-year-old kid proved that you don’t need skill to take a good picture as long as you have a sufficiently capable camera: Nashi, the family Siberian Husky.  This was in a living room with dim lighting, ISO 1600, 1/13th of a second and f/4 at 82mm on the 24-105/4L zoom.  An adult photographer with steady hands would need 1/80th or faster, typically, to get an image without evident camera shake.  The image stabilizer in the Canon lens was good enough to adjust for a 5-year-old kid’s jumpiness.

Tom and I left the Four Points at 0630 and were on the roll around 8:15 am down the runway at Gaithersburg, Maryland, where the winds had calmed down.  We were unable to take advantage of the XM weather data subscription that I pay for every month for the Cirrus because, two months ago, the Avidyne radio receiver decided to deactivate itself.  XM says that we are paid up, that we were always paid up, that the radio should be active, and that they have sent out activation signals.  The Avidyne multi-function display says that our radio is working perfectly, gets a good signal from XM, and that we have no subscription.  The Brave New World of privatized digitally rights managed data sounds good, but when you combine complex business strategies with today’s incompetent programmers, the result is that customers probably won’t get what they paid for.  In an airplane, in the clouds, this is not comforting.  (It is kind of annoying too because the data for which we pay $50/month is all generated by the U.S. government and, in theory, available for free to anyone who can get it.)

At our filed altitude of 7000′, the FAA apparently wants airplanes passing up the East Coast well clear of the jets landing and departing the New York City airports.  We were routed through Lancaster and Wilkes-Barre, Pennsylvania and then over the Hudson River north of I84 and West Point.  The winds aloft were blowing 60 knots, with a 30-knot headwind component (the plane was moving at 150 knots through the air, but going only 120 knots over the ground).  Just after we entered New York State, I called Flight Service to provide a pilot report and get the weather between us and Bedford.  Winds were as expected, out of the northwest at 20 knots, gusting up to 27.  This would be a piece of cake compared to the landing at Gaithersburg.  We had a nice U.S. Air Force runway, almost twice as long and fully twice as wide as the runway at Gaithersburg, oriented to magnetic 290 and thus more or less into the wind.  We relaxed, fat, dumb, and happy until about 30 miles outside of Bedford when we listened to the ATIS, the prerecorded information distributed by the airport controllers to pilots:  “Runway 11-29 closed.  Expect a visual approach to Runway 23.”  [Runway 23 is the shorter “crosswind” runway, typically only used when winds are strong and from the southwest.] It turned out that Massport had decided to redo the sealcoat on the runway that morning.  I called for a wind check.  The wind was from 330 at 17, gusting higher.  Runway 23 has a bunch of little hills in its approach path, which tend to generate some ugly turbulence 100-200′ above the ground.  230 to 330 is more or less a direct crosswind (with a slight tailwind component).  The Cirrus SR20 has a maximum demonstrated (by a test pilot) crosswind component of 21 knots, which was higher than the steady wind, but lower than the gusts.  I asked for 29 and was told that we could have it if we waited 30 minutes.  The prudent pilot would have circled around in the bumps for half an hour or landed into the wind at Nashua’s Runway 32 and had lunch at Sandy’s.  Tom had an important business lunch to attend, however, so we decided to give Runway 23 a try.

We decided to hold an approach speed around 85 knots with half flaps.  The standard half-flap approach speed is 80 knots, but we added 5 knots to make sure that we didn’t get too slow in the event of a big gust.  The higher airspeed makes the rudder more effective and we would be needing most of our rudder to keep the airplane pointing down the runway.  I flew a wider than usual pattern and gave myself a long time to get established on the final approach course and on the visual glideslope, which is a shallower approach than standard in a light single-engine airplane, but about the right angle for half-flaps.  We held a more or less constant attitude over the hills and bumps while the airspeed indicator jumped around between 75 and 95 knots.  The touchdown wasn’t that bad, in the end, and we shut down in time for Tom to make it to his meeting.

Lessons?  Any flight for transportation, as opposed to recreation, requires a high level of training, preparation, and equipment.  If you have to be somewhere specific at a specific time, you will probably get into some kind of a trouble.  Check the NOTAMs carefully (I had missed this runway closure (two lines) in an online briefing (50 pages) the night before, focusing on the weather, after a couple of glasses of wine; a flight service woman didn’t mention it when I called for an updated briefing from the Gaithersburg airport a few minutes before departure).  If you’re going to own an airplane equipped with Avidyne avionics (local MIT spinoff), hire a full-time kid to keep up with the service bulletins, software updates, equipment failures, and shutdowns due to alleged non-payment.

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A friend from Seattle stopped by this morning for breakfast.  He developed a software product that layers some new user interface on top of Windows XP/Vista and we talked about how to get people to use it.  I noted that the original Macintosh OS spawned some successful UI extensions/plugins, notably Boomerang (put your recently accessed files and folders on a pull-down menu in every application), but that since the early 1990s nobody except Microsoft or Apple had been able to foist new user interface off on anyone (and Microsoft’s TabletPC hasn’t worked well at all, achieving an even smaller market share than Mac OS).

So… how come nobody can get anyone to use a user interface plugin that addresses the woeful shortcomings of Windows, notably navigating up and down the hierarchical folders and among all the simultaneously running apps?

The second question that came to mind was what the Apple guys have been doing with their $billions.  Bill Gates and the Microsoft crowd have been very prominent in charitable circles, saving Africans from disease, etc.  By contrast, a Google search for “Steve Jobs charity” or “Steve Jobs donation” turns up nothing except an article on how Apple bought him a $90 million Gulfstream bizjet.

So… if Steve Jobs doesn’t give money to charity and doesn’t pay for his own jet, is he doing something interesting with his $billions?  And what about the rest of the Apple and Pixar crowd?  Are they funding a secret desert project somewhere?

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The exciting life of a helicopter instructor on a rainy/windy day… Captioning and converting camera RAW images on my Dell 30″ monitor, which remarkably is now selling for $1279 (link) and then hitting the MIT pool (subject of an earlier blog posting due to the lack of soap in the showers).  I’ve always had trouble with swim goggles leaking, but for about a year I’ve been using a pair from http://www.aquagoggles.com/, which are even available with corrective lenses for the nearsighted (up to 9 diopters), and they are almost perfectly watertight.  Only have to swim 5 miles a day to lose enough weight to instruct in the R22…

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Yesterday was a proud one for the helicopter division of East Coast Aero Club.  Brad Pretzer and Dale Zeskind passed their checkrides and added helicopter ratings to their existing pilot’s certificates.  Paul Cantrell, Mike Rhodes, and I were relieved, but not surprised, when Don Cody (16,000-hour helicopter hero and FAA designated examiner) blessed our students’ 180-degree autorotations, slope landings, confined area approaches, etc.  Paul Edmonds had come up from Florida to learn how to fly the Robinson R44, so we had a lunch to celebrate his SFAR 73  pilot-in-command signoff and the new ratings for Brad and Dale.

I’d like to thank Brad (Boeing 767 pilot) and Dale (Beechcraft Baron instrument flying hero) for being such easy students to teach and Paul and Mike for their supervision and assistance through this process.  As a novice CFI, it is great to have the experience of 10- and 20-year CFIs available in the same hangar.  I also should thank the guys who trained me for my CFI:  Paul Cantrell, Jeroen Alberts, and Ben Fouts.  Thanks are also owed to Josh Maciejewski, who got the school rolling with a summer of hard work, and Mark Holzwarth, for keeping East Coast Aero Club operating for 20+ years.  Mostly, I guess, we owe our lives and fortunes to Rob Brigham, the helicopter expert on the East Coast Aero Club maintenance team, as well as Adam Harris, Ross, Rick, and Greg.

Aviation is one thing that you can’t accomplish by yourself (at least not safely).

Photos:

• Philip, Brad, Alex, and Dale
• Philip and Paul
• stuffing Samoyed into helicopter: Phase1; Phase2

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I was saddened to learn today of a Cirrus SR20 that crashed into a Manhattan skyscraper, killing Cory Lidle, the New York Yankees pitcher, and Tyler Stanger, a 26-year-old flight instructor from California.  As it happens, I was at the exact same spot yesterday, en route to the Downtown/Wall Street heliport in a Robinson R44.  I have flown my own Cirrus SR20 all the way to the Arctic Ocean and then southwest to Alaska.  Friends have thus been asking me to speculate on how this accident might have occurred.

The airspace around New York City is extremely complex (chart).  There are three Class B airports, LGA, JFK, and EWR, and therefore a lot of protection for jets flying in and out of these busy airports.  You can’t be anywhere near the city unless you are talking to New York Approach, the tower controllers for one of those airports, or over the Hudson River between the surface and 1100′ above sea level (i.e., pretty darn low).

I have often been confused about the East River.  Careful study of the helicopter and terminal area charts has led me to conclude, mistakenly, that it is not legal to fly too far north of the Brooklyn Bridge without explicit clearance from LaGuardia Tower on 126.05.  As Lidle and his instructor probably knew from talking to local experts, it is in fact legal to continue up to Roosevelt Island, at 86th St., without talking to LGA.  In any case, if you continue straight ahead up the river indefinitely without getting clearance (which is easy to get), you are very seriously violating LGA’s airspace.  If discovered, the FAA could have suspended the pilot or instructor certificates of anyone on board the aircraft.

My preliminary best guess (and at this point it can only be a guess) is that the two pilots on board the accident SR20 were cruising slowly up the East River.  At some point, they decided that they’d reached the end of the little cut-out tongue of uncontrolled airspace over the East River.  They attempted a 180-degree turn in an attempt to get southbound down the river toward uncontrolled airspace.  An airplane in a sharp turn stalls at a much higher airspeed than when straight and level.  Merely by putting the airplane into a steep bank and trying to hold altitude, they could have gone from flying to an aerodynamic stall (wings at too high an angle to the relative wind or, in simpler terms, air not moving fast enough over the wings) in a matter of seconds.  At this point, the airplane is not easily controlled and a lot of bad things can happen.  Low-speed low-level maneuvering, which typically happens when aircraft are trying to land, is the leading cause of plane crashes.

[It is possible to turn an airplane tightly and safely and is commonly done inside mountain valleys in Alaska (where guys just love to take off and head towards a pass to see if there is any separation between the clouds and the terrain; if not, they turn around and go back to their cabin).  The trick is to slow down as much as possible.  An ice skater going fast will use up a lot more ice in a 180-degree turn than an ice skater going very slowly.  In an airplane, this means putting out flaps so that you can fly slower without stalling and slowing down to maybe 1.5 times stalling speed (in the Cirrus SR20 this would be about 75 knots with two people on board).  At a slow speed, you have to be somewhat careful with bank angle because you are closer to the stalling speed.  On the other hand, you don’t need a steep bank angle to make a tight turn because you’re only going about as fast as a car.]

[Thursday update:  I was interviewed by a New York City radio station this morning.  The interviewer, as have most journalists, seemed very interested in the Cirrus’s parachute.  People can’t shake the idea that a plane with a parachute is safer than a plane without one, though in this situation, the safest plane would have been an old slow cheap one that could be flown slowly and therefore turned tightly.  The Cirrus is a great plane for going straight and level on a 400-mile trip, but its virtues become liabilities when trying to fly low and slow.

 http://cbs4boston.com/video/?id=25043@wbz.dayport.com is a video clip from the local TV news station that flew with me and Alex this afternoon]

[Saturday update:  found a good table of airspeed/bank versus turn radius: http://selair.selkirk.bc.ca/aerodynamics1/Lift/Min_Radius.html ; my example above of slowing the Cirrus down to 75 knots would enable a turn diameter of 1000′ at a comfortable, yet steep-by-Private-pilot-standards, 45-degree bank angle.  The East River is approximately 2000′ wide.  At a more standard slow pace for a Cirrus of 100 knots and 30-degree bank angle, the turn diameter is 3075′.]

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The recent mid-air collision in Brazil of a new regional airliner (fitted out for use as a business jet) and a Boeing 737 has people baffled.  How could two brand-new airplanes with advanced avionics, flown by two professional pilots in each plane, collide at 37,000′?  The precision of modern avionics may well have contributed to this collision.

Airplanes under instrument flight rules fly from one navigation beacon to another along published standard routes.  In the old days, with radio navigation receivers and pilots flying by hand, a plane wouldn’t fly its clearance exactly.  The airways include a tolerance for error of +/- 4 miles.  If you’re 4 miles to the right of course, in other words, you’re still legal and safe from hitting mountains or other obstacles.  Altitude was similarly sloppy.  If you reached for a drink of coffee or to look at a chart, you might drift up or down 200′.  Air traffic control wouldn’t get upset.

How does it work now that the computer age has finally reached aviation?  The GPS receiver computes an exact great circle route from navaid to navaid.  All GPS receivers run from the same database of latitude/longitude coordinates, so they all have the same idea of where the Manchester, New Hampshire VOR is, for example.  The autopilot in the plane will hold the airplane to within about 30′ of the centerline of the airway and to perhaps 20′ in altitude.  If two planes in opposite directions are mistakenly cleared to fly on the same airway at the same altitude, a collision now becomes inevitable.

Almost any other system would be safer.  If you sent airplanes up to fly in random point-to-point paths, e.g., from Boston to Denver, they’d be less likely to encounter one another.  If you kept the airway system, but introduced some extra logic into the avionics so that planes always flew 1 mile to the right of an airway and + or – 200′ in altitude, they’d be less likely to encounter one another.  If you replaced the precise autopilots with imprecise humans, planes would be less likely to encounter one another.  If you replaced the high-precision GPS receivers with low-precision VOR receivers, planes would be less likely to encounter one another.

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I was giving a lift to one of my helicopter students from the military side of Hanscom Field back to the civilian parking lot.  “I’m driving my [18-year-old] son’s car today,” he noted.  I scanned the parking lot for a 1998 Honda Accord or similar.  He directed me towards an almost new black Mercedes E-series sedan, the $50,000+ dream car of so many yuppies.  “I like all of the airbags,” my friend said.  “He’s already had five accidents.”  Was it a car that this health care professional had bought for himself and then given to the kid?  “Oh no.  I was born to be a father and I just love giving things to my kids.”

Christian Europeans at various points in history passed anti-finery laws prohibiting Jews from wearing fancy clothing or jewelry.  This incident led me to wonder if we shouldn’t have a similar law for teenagers.  We want Americans to work hard and strive to improve their salaries so that they can grow the economy and pay more taxes.  If a guy who is working two jobs to improve his economic situation sees a kid driving to high-school in his own brand-new Mercedes merely in virtue of having been born into the family of a doctor/dentist/lawyer/whatever, might it not demotivate him a bit?

Perhaps I have gotten out of touch with the modern world.  When I attended public high school in Bethesda, Maryland in the late 1970s, a rich kid was one who had a car of any kind.  Has it all escalated to the point where in suburban Boston a kid needs a new Mercedes to hold his head up among his peers?

[Or maybe I’m just envious, driving a 1998 Toyota minivan that smells like a wet dog.]

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Yesterday’s mail contained a newsletter to neighbors (Cambridge, MA residents) from Harvard University.  It was just after I read a news report on Harvard’s endowment, which earned 16.7 percent on an approximately $30 billion stash.  In other words, Harvard earned around $4.5 billion, tax-free.  After deducting for inflation, in other words, Harvard earned enough last year to purchase a nuclear-powered aircraft carrier, complete with a fleet of fighter jets.  What did the letter to neighbors say?  It seems that one day per year, Harvard’s museums, normally $10 per person per museum, open their doors to Cambridge residents for free.  That’s right, 1/365th of the time, Harvard will not collect every last possible dime.  When is this glorious day to occur?  September 17, 2006.  I.e., the “connections” newsletter arrived in my mailbox several days after it would have been possible to visit the museums for free.

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For those who believe that aviation and alcohol don’t mix well, a video of Robinson R22 and R44 helicopters being used to open beer bottles… http://www.glumbert.com/media/beerbottle

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Our summer rental in Lincoln, Massachusetts, a Boston suburb with two-acre minimum zoning, is coming to an end.  My friend Tom asked me whether I was sorry to be giving up the yard, woods, and pond and moving back to my crummy two-bedroom apartment in Harvard Square.  I said, “Well, in three months here I’ve only met one other person.”  Tom said that he’d lived in a Manhattan high-rise and found it difficult to meet people outside of work. The authors of A Pattern Language advocated a three- or four-story maximum height for housing with a lot of public squares, which is sort of what Cambridge is like (sadly the three- and four-story structures are wooden and fell into disrepair 50+ years ago).  It is definitely much easier to meet folks while out walking the dog in Cambridge than wandering around in isolation over the trails of Lincoln.

Could it be that Cambridge has the ideal physical structure?

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