Philip Greenspun’s Weblog

What do three pilots do for fun on a Saturday night? Fly to Nantucket for dinner. We were apparently in a hurry, because we opted to take a Twin Commander 1000. In the 1970s, corporate managers thought it would be the height of luxury to ride in the back of a plane that could seat 8 people, cruised at 300 knots up to 35,000′, with a range of 1800 nautical miles (good to go to Europe with a stop in Iceland). The typical number of passengers carried on a private jet, then and now, is less than 2. In response to this demand, Gulfstream manufactured the Twin Command from around 1973 through 1985. Corporate managers, having figured out that there was nothing to stop them looting an extra $50-100 million from their shareholders, abandoned these planes for bizjets closer in size to a Boeing 737 and Gulfstream followed that market, leaving the Twin Commanders mostly to private owners.

We walked out of Jet Aviation in Bedford around 5:30 pm. The interior of the Twin Commander is cavernous by general aviation standards. Four people would have plenty of room to stretch out in the back all the way to Europe; six or seven would be comfortable on a trip to D.C. Starting the plane’s Garrett direct-drive turbine engines is more or less automatic. Taxiing the plane is famously difficult and the copilot’s seat has limited rearward travel due to a cabinet. My shins were up against a sharp metal piece of the panel and it was hard to work the rudder pedals and toe brakes. Winds were less than 10 knots and more or less straight down Runway 23, the 5000′ crosswind runway at Hanscom. I advanced the throttles to about 80 percent torque and, with about 1400 horsepower on tap, we hurtled down the runway towards a rotation speed of 100 knots. Rotating the Twin Commander requires a heroic tug back on the yoke that would flip a Cessna over on its back. We probably weighed close to 11,000 lbs. and with a plane that heavy, you have to be alert with the trim. Fortunately, thanks to the twin-engine nature of the beast, there were no issues with left-turning tendencies. I was instructed to climb at 120 knots, but was holding closer to 140 and still we were climbing at closer to 1000 fpm.

We contacted Boston Approach and were quickly cleared through the Class Bravo airspace to an altitude of 10,500′. I was “behind the airplane” at all times, just barely able to keep up with attitude, heading, airspeed, and power, while the owner worked the radio. The workload was high, but seemed like it could be manageable. Like the 2006 TBM-700 that I had flown the day before, this 1982 Twin Commander does not offer much integration of information. There are about the same number of switches, dials, and lights as in the TBM.

The weather was severe clear, but it was pitch black and we were over the water. Between the lack of visual references and the limited visibility over the high panel, I found it easier to fly the instruments than the real horizon. Removing headsets, it was remarkably quiet in the cabin, which had been passively soundproofed the last time that the interior was refurbished. It wasn’t that hard to slow the plane down for a 120-knot approach speed on a right base to Runway 24 at KACK. With the gear and full flaps down, we crossed over the threshold at 110 knots and touched down at close to 100 knots (the stall speed in this configuration is 77 knots). The specs say that the plane can be landed in 1300′ with reverse thrust, which we did use; we probably chewed up 3500′ of runway (out of 6000′ available).

Over some cod cakes (the Nantucket equivalent of hamburger), we talked about airplanes and children (the good pilots tend to be successful husbands and fathers as well). I almost always feel good after hanging out with pilots, but these guys were especially impressive for the level of responsibility they are willing to take for their passengers’ safety and also, in the Twin Commander owner’s case, for the level of flying skill evidenced.

We headed back to the airport and fired up. The weather was beginning to come down in the Boston area. We departed VFR and contacted Cape Approach to ask for VFR advisories into Bedford. The controller seemed confused, never got our tail number right, and kept asking us to press the Ident button on the transponder. Finally he said that we were out of his airspace and to talk to someone else, but he didn’t give us a frequency. We used the “nearest center” function on the Garmin 530 to bring up the frequency for Boston Center, the controllers of higher altitude aircraft. A sharp-minded woman answered and gave us an instrument clearance to return to Bedford at 12,000′. At almost 270 miles per hour over the ground, I was just getting organized when it was time to descend towards Bedford. The wind was about 6 knots right down Runway 23 and the controllers were proposing a non-precision VOR approach to 23. That would have involved a bit of extra flying to the NE side of the airport and it is safer and easier to fly an instrument landing system (ILS) approach, so we asked for the ILS 29 instead. We entered the clouds at around 7000′ and kept getting closer to the final approach fix without getting clearance to a lower altitude. Finally we were cleared down to 2000′ and we pulled the power back to idle and nosed over for a 3000 fpm descent. To my piston instincts, it felt wrong to be hurtling towards the ground so fast, but because the Twin Commander is pressurized, I didn’t feel anything in my ears. We slowed down to 120 knots and dropped the gear as we intercepted the glide slope. The ILS was uneventful and we broke out at 1300′, about 1200′ above the runway, then continued visually to land. Despite cutting the power and aiming just beynd the numbers of 29 rather than for the 1000′ markers, our touchdown speed of close to 100 knots kept us moving all the way to the intersection with Runway 23, i.e., we used about 4000′ out of the 7000′ runway. It was easy to keep the plane straight against the light crosswind.

This is a great airplane that is beyond my current level of piloting skill, but the owner, a Twin Commander expert, thought that I would be able to fly it safely by myself in reasonably good weather after 25 hours of flying as a copilot. It is quiet and comfortable in the back, good enough for anyone not spoiled by a Gulfstream GV or Boeing Business Jet. It has the speed and range to go anywhere in the world.

What are the practical aspects of owning a Twin Commander? $1-2 million to buy. 100 gallons of jet fuel per hour (approx. $400) plus maybe another $500 per hour for maintenance. Insurance would probably be $40,000 per year. Better to take JetBlue if you want to go somewhere obvious like San Francisco or Los Angeles…

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As the Internet gets faster and collaboration tools get better, it is very hard to explain why one needs to travel. Nonetheless, some of my friends have decided that we need to be able to get around by airplane in the winter and do so on our schedule. This means we need an airplane that can climb through ice-filled clouds into dry clear air. The TBM 850 is one candidate and we flew one today out of Hanscom with the regional sales guy, Ken Dono. [links: the plane in general; the plane we flew]

Weather was clear with winds gusting to 20 knots and an airmet for moderate turbulence below 8000′. I buckled into the four-point harness in the left seat with Ken on the right. Pre-start checklist involves setting up diverse switches to appropriate settings and giving the emergency oxygen system a try. The start procedure is typical of a non-FADEC turbine engine. You hold down the start switch and monitor the temperature to make sure that the engine doesn’t get too hot. Once the RPMs are in the green, you let go of the start switch.

I was able to taxi out to Runway 29 without embarrassing myself. The torque gauge lags the throttle a bit and, in attempting to advance to 100% torque, I pushed the engine up over the redline to 105% (oops). We rotated at 80 knots, climbed at 110, and, after retracting the flaps, pitched for 120 knots. We did most of our climb up to 16,500′ at 140 knots, achieving a cruise climb rate of 1500-2000′ per minute. Managing the rudder trim was a bit of a challenge through the climb out and level-off.

I did some turns at 30 degrees of bank and then reconfigured the plane for landing and did some maneuvering at 95 knots with full flaps. The plane is very docile and easy to handle. We did an emergency descent at 6000 fpm, the appropriate action to take in event of a pressurization failure. Ken kept having to tell me to “push down more” because it seemed wrong to nose the plane so far over (the red line is at 266 knots).

My friend Julian took over at the controls for the trip back towards Hanscom. Swapping pilots in the tight cabin is awkward, but doable. Julian is halfway through his instrument rating, a relative beginner pilot, but he was able to bring the plane in for a smooth landing with a bit of coaching. Thanks to some reverse pitch on the propeller, we made the very first turnoff from Runway 29 at Hanscom, Taxiway Golf. I think it is about 1800′ from the runway threshold. This is a plane that is as fast as some turbojets and yet can land at almost any airport in the U.S.

How about interior comfort? The noise levels at a 260 knot, 16,500′ cruise were 91-92 dBA in front and 88-89 dBA in back, i.e., comparable to, but not superior than, the quieter piston airplanes. The front seats are comfortable, slightly cramped, and offer fair visibility. The rear seats are comfortable for two, but would have been cramped for four tall adults. The rear seats have limited visibility through small windows that are much lower than eye-level (i.e., much worse than a window seat on a 737) and are afflicted with a fair amount of yaw (“tail-wagging”) and turbulence. The plane carries about four hours of fuel, plus a reserve, and has… no bathroom or “relief tube” (don’t ask, but most of the higher-end piston airplanes have them; remember how Tycho Brahe died). It would be tough to imagine a rich person paying for a ride in the back of this airplane.

How does the airplane compare to the new Very Light Jets (VLJs)? The TBM user interface is squarely in the mold of airplanes that have been with us since World War II. Every time a new system is added to the plane, some new switches, dials, knobs, warning lights, and test switches for the warning lights are added to the panel (dashboard). There are about seven switches that turn on different anti-icing subsystems. You’d think that this would be a three-position switch: “no ice is possible” (everything off), “ice is a theoretical possibility” (pitot heat on to both tubes), “I am picking up ice” (everything on). But nothing like this level of integration is present in the TBM. The VLJs, by contrast, present most of their information on three big LCD screens, very similar to the two big LCD screens on simple piston airplanes being delivered today. They don’t need a grid of 50 warning lights and associated test switches. If you can see a big LCD screen, any warnings that you need to see will appear as text on the screen. The integration on the Eclipse jet is so high that it is probably going to be simpler to fly than the TBM.

What is the competition for the TBM?

• Pilatus PC-12: longer range, slower cruise speed, much larger cabin, similar hourly costs
• King Air: two engines, 6000 out there flying, can replace all the avionics in an older one with a Garmin G1000 and Garmin autopilot for about $225,000, slow cruise speed, limited range, higher hourly costs due to two engines spinning towards overhaul
• the VLJs: starting at $1.5 million for the Eclipse, potentially much cheaper than the TBM and maybe a lot quieter inside, but also very cramped

The TBM does seem to be the champ for a plane that a low-time owner can fly by himself to reasonably short runways.

Related: Pilatus PC-12 quick review

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The U.S. Air Force announced today that it will be using the Boeing HH-47 as its new combat search-and-rescue helicopter, starting in 2012. The HH-47 is a variant of the CH-47 Chinook, “the only aircraft that can have a mid-air collision with itself.” This machine was designed in the late 1950s, first flown in 1961, and first used by the U.S. military in 1962.

There were a couple of competitors for this $10 billion program. They had the advantages of fifty years of improvements in engineering education, an average rising IQ, modern computers and computer software for simulation… and they lost to a group of engineers who grew up driving Model T Fords.

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We went out to run some errands today and passed near to the house of an old friend who is a constant complainer. It struck me that someone who complains constantly should be marked down as remarkably optimistic. The complainer believes that people actually might care.

Who are the true pessimists? People who never complain. They are so far into the depths of despair that they’ve lost hope that anyone is listening.

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Now that the American people have registered their dissatisfaction with George W.’s Iraq policy, I think it would be a good time to review the Iraq-related writings in this blog:

April 15, 2003: I noted that it didn’t take long for the U.S. military to beat the Iraqi military, the “war” having lasted less than one month.

April 23, 2003: I advocated breaking up Iraq into three countries, one Kurdish, one Sunni, and one Shiite (and presumably taking a leaf from the British book and giving ownership of each to a friendly (to us) local strongman)

June 4, 2003: Bad intelligence over weapons of mass destruction in Iraq compared to a similar situation in WWII.

June 6, 2003: “Saddam may yet go down in history as the kindest and gentlest 21st century leader of a unified and stable Iraq.” (I think this one is holding up pretty well!)

July 3, 2003: I wish that George W. Bush would stop taunting Iraqis with guns.

July 21, 2003: Iraqis will be poor even if they crank up oil production. (includes the now-ridiculous assumption that oil will sell for $25/barrel… oops)

September 4, 2003: I bemoan the fact that we’re spending $100 billion to rebuild Iraq instead of on tech infrastructure for the U.S. [ridiculous posting now that people are estimating the total cost of our Iraqi adventure at $1-2 trillion]

September 26, 2003: skepticism that Iraq can be pacified within the $100 billion budget.

November 11, 2003: conversation with a reporter who had visited Iraq and said ““Iraq isn’t a country; it is three countries: a Kurdish north, a Sunni center, and a Shiite south.”

January 20, 2004: making fun of Howard Dean’s vacuous plans for America (the Democrats seem to have come up in the world since then, or maybe the Republicans have come down (the old joke was “one notch below child molestor”, but I guess that isn’t funny in the context of Republican politicans anymore))

March 11, 2004: musings about how we make foreigners angry and then have to tax ourselves to build more military capacity to go and attack them

April 11, 2004: pointing out that we will never be able to win in Iraq because we only attack governments, not civilians, and in Iraq it is the civilians who want to kill us

May 27, 2004: proposal that we give Iraq back to Saddam and apologize (I guess this won’t work too well after they hang the guy)

June 7, 2004: Ahmad Chalabi turns out to be an MIT graduate

July 16, 2004: Why we hate Bush more than Reagan (Reagan concentrated on domestic challenges; my assertion is that George W. is actually an Iraqi)

July 24, 2004: complaining about George W. glorifying angry Muslims (by talking about them all the time instead of letting a lower-level official deal with our antagonists)

November 28, 2005: conversation with a guy who had spent two years in Iraq: ““Democracy is a foreign concept to them, as is capitalism. Whether we get out in six months or ten years, our definition of success is not going to be a nation like our own.”

Probably I’m just in love with my own ideas, but imagine if George W. had done the things that I suggested:

• never personally mention Iraq or any Iraqis, delegating the entire affair to lower-level officials
• pull our military out after military victory had been achieved, splitting Iraq up into three new countries or handing it back to Saddam (all in 2003)
• concentrated his personal energies and speeches on doing things for Americans in America

I don’t think the Republicans would have lost the recent election so badly. (Though perhaps they needed to lose since they had become complacent, sending guys like Mark Foley to Capitol Hill, and cranking up public spending to frightening levels.)

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The Picasso show at the Whitney has some of us talking… “How often does a painter as good and innovative as Picasso come along?” One theory is that there are a lot of people who could be very talented painters, but they choose to do other things with their lives unless there is some kind of innovation in the art world that makes painting a congenial place for a creative person. Thus Picasso might have done something else if not for the fact that the Impressionists opened up a world of possibilities. In the history of painting, who are the folks who stand out as much as Picasso and how often have they come along? Some possibilities: Da Vinci, Michelangelo, Titian, Rubens, Vermeer, Goya.

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Can one do RAID 1 over a network? Alternatively, one might ask “Has any progress been made in file systems in the 20 years since AFS?” We’re trying to build a more capacious and reliable photo sharing system for photo.net and would like to avoid giving a lot of money to EMC (since we don’t have any money) for one of those fancy shared fiber channel disk arrays. http://www.photo.net/doc/design/photodb-arch lays out our goals. Comments from sysadmin geniuses would be appreciated!

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I know that there are a lot of sysadmin/networking experts reading this Weblog, so I’m appealing for suggestions on the following question: What is the best open-source software for a firewall/load balancer to be used at photo.net?

http://www.photo.net/doc/design/firewall-load-balancer-200611.txt

Explains what we need.

Thanks in advance for your help.

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We’re about to vote in Massachusetts. A variety of folks are vying to become governor. Nobody seems to notice that the existing governor, Mitt Romney, didn’t accomplish anything substantial during his four years in office. It seems that the office is purely ceremonial and that all of the power is with the legislature.

Ted Kennedy is running more or less unopposed for Senator. I’m not sure what it says about a state that nobody more sober and worthy than Ted K. can be found to run for national office. I’m not sure if politicians can still take home their unused campaign funds when they retire, but Ted supposedly has more than $7 million in the bank that he won’t be spending.

Speaking of national office, John Kerry isn’t running, but he is talking about how poorly educated our military personnel are. All of the folks I’ve met who served in Iraq seemed to be of above-average motivation and education. On the same day that Kerry was in the news, I had lunch with one of my instrument airplane students. He is a U.C. Berkeley-educated engineer who has worked designing high-speed CPU chips. At the age of 35, he has decided to apply to join the Army Reserve as a helicopter pilot. I asked if he was concerned about the possiblity of being sent to Iraq. “If they asked me, I would be honored to serve.”

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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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