Thursday, December 31, 2009

Happy New Year (with a look back...)

It's already 2010 on Zulu Time (0310Z as I type) but the local clock still has a couple of waning hours of the first decade of this century, so perhaps you'll bear with me as I take a few minutes to look back at what N631S and I have done in 2009.

With my full year of the regular weekly commute between the DC area and Bridgeport, I logged a lot more hours than in any previous year...to be exact, 207.2 PIC hours. Of that time, 18.4 hours were at night and 26.7 hours were in actual instrument conditions.

The log shows 18 instrument approaches this year; 15 in actual conditions and 3 "under the hood". One of the "real" approaches ended in a miss at KVKX and a diversion to my alternate at KHEF (discussed here).

One of the three practice approaches was logged on a 0.7 hour local flight in January for which I also logged 0.7 "dual received" from my friend Bob Parks. I believe that was Bob's last instructional flight at the end of two-thirds of a century as an instructor. His health began to fail soon after that and he "went West" in July. I miss him.

Through it all, N631S was a remarkably reliable machine, allowing me to make the round trip between KBDR and KVKX 35 and 1/2 times. The only notable equipment malfunction was a vacuum pump failure.

Winter is present in full force here in the northeast, so I'll be availing myself of AmTrak quite a lot in the coming weeks (as I did this week). It was nice knowing that N631S was snug in its hangar at Potomac Airfield.

It's my hope that the changing (dare I say improving?) economic climate will permit some corresponding changes in my schedule, allowing me more time in Virginia and fewer trips to KBDR. Time will tell.

I wish for all of you a healthy, safe and prosperous new year. OK, now it's time to go watch Guy Lombardo and His Royal Canadians ring in the New Year. No, wait... Not any more? Well, I guess I'll just turn in. See you all next year.

Thursday, December 24, 2009

NORAD Has Santa Contact

With links to Google Earth and videos of St. Nick in various airspaces.

Official NORAD Santa Tracker

Smiles here, for sure.

Joy of the Season

My thanks to all who visit here, with the hope that all of you have a festive and joyous holiday season!

And to all, best wishes for a healthy, safe and prosperous 2010.

Wednesday, December 23, 2009

Circuit Breaker Safety (cont'd)

A post on this blog from back in July titled Circuit Breaker Safety called attention to aspects of the NTSB report on the NASCAR Cessna 310 accident in Sanford, FL that was attributed to an uncontrollable in-flight electrical fire. In particular, it suggested that the time-honored practice of resetting any tripped circuit breaker one time is badly in need of reconsideration.

Now comes the FAA with Special Airworthiness Information Bulletin (SAIB) CE-10-11 on this topic.

I urge you to read the post linked above and then read the SAIB...and ensure that your flight SOP's are consistent with current guidance. An in-flight fire can ruin your whole day.

Tuesday, December 22, 2009

NEXRAD in the Snow

My last post was a straightforward account of the flight from KBDR to KVKX last Friday evening, arriving a bit ahead of the approaching snowstorm.

As I neared the end of the flight the NEXRAD display provided by XM Weather on my Garmin GPSmap 396 showed a broad field of snow (light blue) nearly encroaching on KVKX, but neither the METAR's at KDCA and KADW nor the view out the windshield indicated any imminent problem. I evaluated the radar display as precipitation aloft, somewhere above the existing overcast ceiling that was up around 11,000 feet MSL.

Back in the summer I'd learned a bit about the differences between NEXRAD base images and composite images of convective weather (and posted about it here and here). Now I inferred that I was seeing the same thing, but with snow.

Last evening I decided to pull out archival NEXRAD images showing the base returns and composite returns for the Sterling, VA radar site at the time I was approaching KVKX on Friday. (The procedure for recovering archival NEXRAD images is outlined in this post.) In looking at the graphics, bear in mind that the terminal part of my flight was over KBWI, thence to OTT, thence direct to KVKX. Here, first, the base return image:

For scale, it's about ten nautical miles from OTT to KVKX, so the approaching weather is ten or more miles away. As it happens, snowfall did not begin at nearby KDCA until nearly two hours after the timestamp of this image.

In contrast, here is the composite return for the same time:

The XM Weather display on the Garmin did not look this bad (I wish I'd thought to photograph it). But it certainly looked more widespread and advanced than the base return image shown earlier. The takeaway is, I guess, that it's conservative to take the composite radar image at face value when planning your flight track but sometimes other evidence (e.g., METAR's, PIREP's, the Mark I Eyeball) will reveal that conditions at the base level are not nearly so problematic.

Friday, December 18, 2009

The Gathering Storm

My, but it was cold this morning when I went to the airport (KBDR) to give N631S a "pre-pre-flight" inspection in anticipation of an afternoon flight to the DC area. There was 10 knots of wind out of the north and the thermometer offered 14 Fahrenheit degrees. Really, really cold...this was the METAR:
KBDR 181152Z AUTO 34010KT 10SM CLR M10/M19 A3027 RMK AO2 SLP251

I stowed the baggage and proceeded to check out the airplane. Uh-oh...the nav lights didn't light. Cycling the switch several times was of no help. Bad news, as I was certainly not going to be arriving at KVKX before dark. So, off to see the Three Wing maintenance folks. Tony said they'd pull N631S into the hangar and have a look; I suggested that I needed to be ready for a 21Z departure as the weather from the south was threatening to arrive in my home area around 00Z.

As the day progressed I watched the weather and became a bit uncertain about the conditions I could expect at KVKX on arrival. Better move up the departure! I called ThreeWing and asked them to try to have the airplane ready for a 20Z departure.

Arriving at KBDR a bit before 20Z it was hard to believe that weather was going to be an issue. Conditions were quite pleasant, with clear skies, a zephyr of wind out of the northwest and a temperature just a degree below freezing. Here's the METAR:
KBDR 181952Z 32005KT 10SM CLR M01/M20 A3016 RMK AO2 SLP214

And, at that time, destination weather looked good. Here's the METAR for KDCA, offering little wind and a 9,000 foot ceiling:
KDCA 181952Z 08003KT 10SM BKN090 BKN250 02/M08 A3015 RMK AO2 SLP207

The forecast was indicating that snow would begin in the DC area around 01Z and I wanted to arrive well before that event. The good news today was that winds aloft were relatively light. The computer projected a flight time of about 2 hours + 14 minutes.

I was off the runway at KBDR at 2017Z. Flight conditions along the route were as forecast and N631S and I arrived in the DC area about 2220Z. As we approached KVKX for a visual approach to landing, this METAR was current at KDCA:
KDCA 182152Z 14003KT 10SM BKN110 OVC150 01/M08 A3013 RMK AO2 SLP203

I was on the runway at KVKX at 2232Z. It's good that I completed the trip in a timely fashion. Snow began to fall at KDCA at 0133Z, just two hours later.
KDCA 190139Z 08006KT 10SM -SN OVC030 00/M10 A3005 RMK AO2 SNB33 P0000

I suppose I could have been comfortable with a departure about 30 minutes later than actual, but an hour would have been cutting it too fine.

In any event, here is the flight track courtesy of FlightAware. Note the approaching weather in the southwestern quadrant.

It appears that we will be getting something between 14 and 20 inches of snow here in northern Virginia over the next 24 hours. The latest forecast for KDCA is certainly full of snow:
KDCA 182320Z 1900/1924 12004KT 5SM -SN BR BKN015 OVC030
FM190200 06007KT 1SM -SN BR BKN005 OVC010
TEMPO 1903/1905 1/2SM SN BKN001
FM190500 03009KT 1/2SM SN BKN003 OVC005
TEMPO 1905/1909 1/4SM +SN VV001
FM190900 02014G23KT 1/4SM +SN BKN001 OVC005
FM191500 36015G25KT 1/4SM +SN OVC004
FM192300 36014G23KT 3/4SM -SN BKN003 OVC010

That's calling for heavy snow from about midnight tonight until about 6 PM local time tomorrow. It's nice when the timing of a flight works out.

Wednesday, December 16, 2009


We who linger at airports and mess about with airplanes will occasionally, when grounded by weather or mechanical misfortune and forced to settle for hangar flying, resurrect and recycle the everlastingly interesting discussion that seeks to name "The Most Beautiful Airplane Ever Built". I think that the question is misguided. It seems to me infelicitous to force comparisons of relative aesthetic merit between radically differing types. My thought is to award four "Most Attractive" trophys to the Best of Breed in these categories: Single Engine Prop; Single Engine Jet; Multi-engine Prop and Multi-engine jet. As you might expect, I have opinions that I'm willing to share.

In starting with single engined propeller-driven airplanes, I immediately encounter a problem. I've never been able to settle on one exemplar to regard as the Prettiest Bird. In this category, I have to settle for a tie. On one hand there is Reg Mitchell's immortal Spitfire. For anyone who has studied aerodynamics, the perfection of the Spit's elliptical wing planform cannot help but make the heart beat faster. And all of her other lines flow harmoniously into that wonderful wing.

But on the other hand, Walter Beech's beautiful D-17 Staggerwing biplane clamors for attention. The genius of that reverse decalage inspires awe. It was agile, it was fast and above all, it was gorgeous! By all accounts, the Staggerwing has a nasty bite on the ground but any vices have to be forgiven in the presence of such beauty. (And, it's the only one of my "Beautiful Birds" that I can even dream about actually flying someday.)

So there I'm left, Staggerwing or Spitfire. Which is the more beautiful? I can't say - you decide.

When we turn to jet-propelled aircraft, life is easier. Think about single-engined jets and the grace and cleanliness of line offered by the Sabre, product of Ed Schmued's team at North American, come immediately to the fore.

The early versions of the design were straight-winged, like a P-80 or an F9F. But North American's designers were exposed to the research product of the German aerodynamicists and they understood what to do. The lovely, clean swept wing of the Sabre emerged. Other fighters have come along that will outperform the F-86 by a wide margin, but none exceed her beauty (though the Hawker Hunter comes close).

Turning to multi-engined aircraft, and starting with propeller-driven designs, there is in my mind only one answer. My friend Dennis Wolter, a profoundly talented industrial designer, said it well when he told me, "The Lockheed Constellation is the most beautiful industrial artifact ever created by man." The triple-tail, the gentle dolphin-curve of the fuselage, the slender wing supporting the four powerful Wright R-3350's are iconic and incapable of duplication. The Connie of my youth will always be, for me, the Angel of the Airways.

Again leaving behind propeller generated thrust and turning to jets, it is once more an early design (as the Sabre was) that embodies best the natural beauty enforced by natures laws of fluids. What could be more pleasing than the form of Boeing's Stratojet, the B-47? Pilots who had to fly it in defense of our nation will tell you that she was a bitch. Underpowered, and harboring lurking aerodynamic vices, the Stratojet insisted that you be on top of your game and imposed a terrible penalty if you were not. But was she not so very beautiful?

For a good number of years, that's been my take on the "Most Beautiful Airplane" question. Spit or Staggerwing for piston singles, the Sabre for a single engined jet, the Connie for the multi-engined prop and the Stratojet for a multi-engined jet. Many designs have come along, none have prompted me to change my judgement. Most certainly, the utilitarian but (in my view) unlovely A380 has no claim on exceptional beauty or grace.

But recently...in fact, yesterday...things may have changed. Yesterday, the Boeing 787 took to the sky for the first time. And she is such a beauty!

I submit that this is one really gorgeous airplane. Look at the arc of the composite wing under the force of lift. It brings to mind some great-spanned albatross gracefully alighting - or perhaps an owl swooping down over a field to snatch up a wayward vole. This image says to my heart, "Here is a creature of the sky." Many airplanes can be made to fly; this airplane belongs in the sky. Many years ago my aerodynamics professor, Dr. Jack Werner, said to us, "Don't trust an ugly airplane." His point was that nature imposes an aesthetic, and the greatest flying machines work in concert with that aesthetic and never in contravention of it. I feel that the 787 would have pleased him.

The Boeing design team deserves rich congratulations. After a troubled gestation we may find that, in their Dreamliner, they have wrought a classic. And if the B-47 Stratojet is to be displaced as the Most Beautiful Airplane in the multi-engined jet class, it's fitting if the Dreamliner, a product of the "home team", turns out to be its successor.

Monday, December 14, 2009

Ground Fog

THE FOG comes
on little cat feet.

It sits looking
over harbor and city
on silent haunches
and then moves on.

--- Carl Sandburg

The fog seems also to be fond of aerodromes. A nice layer of radiation fog was nestled across the runway when I arrived at KVKX this morning about 1210Z. According to Paul Freeman's fascinating Abandoned and Little-Known Airfields site, before KVKX was called Potomac Airfield it was Prince Georges Airpark and before that it was Rose Valley Airport. And it is in a valley. This results in pleasantly calm wind conditions much of the time, and a tendency to collect ground fog.

From midfield the trees beyond the end of Runway 6 were lost in the mist, so it seemed that visibility was less than 1/4 mile. There was naught to do but go about getting N631S ready for flight and wait for the rising sun to accomplish its thermal task.

In truth the fog wasn't a complete surprise. I'd checked the weather at about 1130Z. At that time the METAR for KDCA was encouraging:
KDCA 141052Z 19003KT 10SM SCT130 01/00 A3016
But the word from KADW was less so:
KADW 141129Z AUTO 20004KT 1SM ... BR CLR M01/M01 A3013

Still, a mile isn't bad...but it would get worse before it got better.

I took my time pre-flighting N631S while the Tanis heater warmed the engine, then started and taxied to the fuel island and topped off the tanks. By the time I'd finished fueling and checked the weather in the office again the sun was visible through the murk above the tree line, and the density of the fog seemed to be waning. The on-field weather instruments soon were claiming a mile and I could see past the end of the runway, so I called Potomac Approach for my clearance and headed out just before 14Z, about an hour later than I'd have been sans fog.

The fog was certainly thinning, but visibility was still limited - until I'd taken off and climbed to about 200 feet AGL where there was all of the blue sky and sunshine one could wish for. The balance of the trip to KBDR was uneventful, in clear VMC with a fair tailwind.

Sunday, December 13, 2009

That Wasn't So Bad!

Flight conditions for the trip on Friday evening from KBDR to KVKX were about as anticipated. Clear skies and prodigious winds out of the west-northwest. But except for a little turbulence climbing out from KBDR that might have risen to "moderate", and a few minutes of light chop near Baltimore, the flight was smooth. Slow but smooth.

For the most part I was looking at ground speeds in the mid-80's to low-90's of knots on the westbound legs (i.e., KBDR to SAX and SBJ to ETX). At one point, just before turning south near Reading, PA the ground speed dropped below 80 knots for a couple of minutes. That's about a 55 knot headwind component. In general, though, the more southerly bits of the trip went quite a lot quicker. Total tach time was 2.9 hours which is nowhere near a record. The weather was fine, I had a quick visual approach to land at KVKX, and ATC helped here and there with shortcuts to speed me on my way.

And now, a word about pre-heat systems...

I'd like to add here an unsolicited testimonial for the engine pre-heat systems supplied by Tanis Aircraft. N631S came to me with a Tanis TAS-100 system installed on the Continental O-470U engine. It is comprised of individual resistance heating elements installed in the temperature probe wells of five of the six cylinder heads and a pad heater attached to the engine block. (There's no cylinder head heater on the #3 cylinder because its probe well is occupied by the thermocouple for the original equipment CHT gage, which must remain installed and functional. This is fine because the #3 cylinder heats satisfactorily by conduction from the rest of the heater array.) When the Tanis system is connected to 110v AC power it nicely heats the engine in a couple of hours to facilitate starting in cold weather.

Friday afternoon brought the first actual cold weather start of the season, with sub-freezing temperatures at KBDR. I asked the line crew at Three Wing Flying Services to plug in N631S's Tanis after lunch, which they did. When I got to the airplane and turned the key it started as readily as if it were a warm spring day.

I've had lots of opportunities to thrash around with propane fired pre-heaters and I am fully convinced that an electric engine pre-heater (of which the Tanis system is a fine example) is one of the greatest blessings that can come to a pilot who has to start an airplane in the cold. Just make certain that you tie down within extension cord range of AC power!

Tomorrow is looking flyable!

It's raining fairly steadily here in Virginia as I write this, but it's supposed to stop by about 00Z. The forecast for tomorrow morning at 12Z is calling for a few low clouds and a scattered layer at 5,000 feet along most of the route up to Connecticut. Best of all, the freezing level is expected to be above 9,000 feet MSL almost all the way to JFK. So, it appears that a nice IFR flight can be planned.

Wednesday, December 9, 2009

We'll Try It Again!

Here it is Wednesday evening and the weather forecast for Friday is (more or less) promising for a flight from Connecticut down to the DC area. The projected map looks like this:

I can expect the high centered over eastern Tennessee to dominate the weather over the route. That will mean high clouds (if any) and no precipitation...so, no icing. But the isobars circling the low that will be far to the north over Ontario look pretty tightly wrapped. That will produce a lot of wind out of the west.

Here is the projected wind pattern for 00Z Saturday (i.e., 7 pm EST Friday evening) at 9,000 feet MSL. (I'll certainly be cleared for 8,000 feet MSL out of CT and over Eastern PA):

That looks to me like 55 to 60 knots of wind out of the west over my route to Allentown. The westbound portion of the flight looks to be a long, slow slog, and the southbound part - quartering into the strong westerly - won't be much better. I'll need to look at the winds forecast for 6,000 feet MSL, or lower. The best scenario may prove to be 8,000 until across the Newark (KEWR) arrivals, then descend to 4,000 past Allentown, Reading and Lancaster, then climb back to 6,000 to get across Baltimore (KBWI).

And I can hope that the low will have gotten far enough to the north that the winds will be steady and strong but not terribly turbulent. We shall see.

Friday, December 4, 2009

Ice Isn't Nice

Well, I've declared "AMTRAK Weather" for today. Here's why:

Conditions here in Connecticut are lovely but some unpleasantness has crept into the southern end of my proposed route. There is a stable sub-freezing cloud layer from 4,000 to 6,000 MSL reflected in the TAF's from DC up to Harrisburg. As the pirep graphic shows, there have already been a fair number of ice encounters, one described as "moderate", and there's no reason to expect things to improve.

The "Moderate" icing pirep got my attention. It was filed by the pilot of an Embraer 190 regional jet just about over KVKX, describing moderate rime ice from 5,000 to 6,000 feet. I really don't want to go there.

So I shall proceed on the ground, wishing I could be in the air but knowing that this is a lot better than the other way around.

Thursday, December 3, 2009

Hail to the Chief, Redux

He's doing it again. El Presidente is travelling to Allentown, PA tomorrow accompanied by his usual two-tier Temporary Flight Restriction (TFR). As of now the enabling NOTAM tells us that the restrictions go into effect at 1450Z and continue in force until 2140Z. Once again, the FAA has been kind enough to provide a graphic interpretation of the boundaries of the TFR:

The red line I've added to the graphic is my usual IFR clearance for a Friday afternoon trip from Connecticut to DC. As you can see, it goes right through the heart of the inner TFR core (the smaller thin red ring). Now, N631S and I are not going to be leaving KBDR any earlier than about 2130Z, so if the Man is on schedule the tents will be folded and the circus gone from town before I get there. But if he runs late I wouldn't be surprised to find the TFR extended to a later hour.

So, I'm going to file for a more southerly route - the blue line on the graphic, via Pottstown (PTW) VOR and thence on down toward Baltimore. If ATC will clear me for that route then all is well. It goes through the outer ring of the TFR (the larger thin red ring) but that's transparent to me since I'll be on an IFR flight plan. But if they insist on issuing me the usual "preferred" route then I'm just going to have to stay alert and insist on an en route deviation if required to circumvent the TFR (if it is still in effect).

That said, the good news is that the weather looks like it will cooperate. The freezing level charts are saying that it's going to be cold up there but the TAF's are all calling for high ceilings (if any), so icing shouldn't be an issue. I expect moderately strong headwinds and a flight time of about 2.8 hours. For December, it should be a nice trip.

Wednesday, December 2, 2009


This Glossary is intended to provide some idea of the meanings of abbreviations, acronyms, jargon and terms of art that may find their way into posts without adequate definition. It will be maintained in the sidebar and will always be a work in progress, as I will add to it and refine the definitions as allowed by improved understanding and corrective inputs.

These are not definitions that I've looked up. They represent my understanding of the meanings of the terms, and that may evolve. If you think I've got something wrong, please let me know via the comment field or by e-mail (the address is in my profile).