Saturday, December 31, 2011

Happy New Year (with a look back)

This is the third year that I've used this post title on 31 December. A year ago, I looked back on 2010 in this post, and a year earlier I reviewed 2009 in this one.

N631S finished the year with 4,207.3 hours on the tach, having flown 175.8 hours in 2011. That's really very close to the 2010 total of 177.9 hours. I made the round trip from KVKX in Maryland to KBDR in Connecticut and back 34 times this year, three and a half fewer than last year. That's in addition to a trip from the DC area down to the Carolina Outer Banks, thence inland to Nashville and back to home plate.

I logged 10.0 hours in actual IMC (instrument meteorological conditions) this year, compared with 2010's 12.9 hours. The weather has been good! The down-side of this is that this year's total of 10 instrument approaches flown in actual conditions is down from last year by four. Time logged as night this year was 10.2 hours, not materially different from last year's 9.2.

Since N631S came to us in 2004, it has been a remarkably reliable machine. But age may be catching up with it a bit, for this year has been – shall we say – maintenance intensive:

And the last item in the above list calls for a mea culpa from me regarding the recent absence of posts here. The December weather has been remarkably cooperative, allowing flight from KBDR to KVKX on the Friday before Christmas (with due attention paid to potential icing), then a return to KBDR after the holiday weekend, and finally, back to the DC area this Friday past to end the year. Each of these trips was completed uneventfully. Let me just offer this video clip, collected over central New Jersey whilst headed south at 6,000 feet on the 23rd, just above the solid, cold and icy undercast. As always, ATC was concerned and helpful:

And finally, may I wish all who may visit here a healthy, prosperous and safe 2012.

Thursday, December 22, 2011

Life's Little Annoyances

It's been one of those weeks.

On Monday morning, I got to Potomac Airfield (KVKX) early – before 6:00 AM local time. The temperature was 28ºF, so I immediately plugged in the Tanis pre-heat system and the quartz heater for the cabin. An hour of that and I'd be on my way.

A few minutes before 0700 I collected my clearance then disconnected the heaters and pulled N631S out of the hangar. And after a bit more housekeeping, got on with the starting program. And achieved no success at all. The voltage readout said 10.4v and the propeller said, "I don't think so."

I called Potomac Approach's Mt. Vernon Sector to let them know I would not be popping up on their scope when expected, and then I called Dan Fragassi at Clinton Aero Maintenance and asked if he would kindly drive over from Hyde Field with a spare battery and a Cessna jumper cable to get me started. Dan said, "Be right there," and thirty minutes later, there he was. Another five minutes and N631S was started and underway.

The good news of the morning was that there was a spanking tailwind yielding ground speeds of about 160 knots as I headed north. Soon N631S and I were over New Jersey and talking to Atlantic City Approach. Soon after checking on with A.C. Approach I heard, "Cessna 631 Sierra, turn 20º left, this will be a vector to Coyle." Cool! A shortcut! I clicked off the S-TEC GPSS module that was allowing the Garmin 530W to control the S-TEC System 50 autopilot – leaving the autopilot in Heading mode – and rolled the heading bug to the left.

Soon, the controller issued "direct Coyle" and I made the necessary key-presses on the 530W and clicked the switch to turn on the GPSS function. And for the second time that morning, the machine said, "I don't think so." No joy – the switch was ineffective.

I completed the trip using manual control of the autopilot in heading mode, and hoping that this wasn't a case of things coming in threes. Two failures in one day were sufficient. On arrival at Sikorsky Memorial (KBDR), after N631S was covered and tied down, I asked Three Wing maintenance to have a look at the battery and at the GPSS switch.

When I checked back with them early on Wednesday morning the news was not wonderful. '31S's battery was not happy. The battery is a Gill G-35 flooded electrode unit (see left) a bit more than two years old. I was told that it seemed to charge satisfactorily but that the electrolyte was discolored and they were concerned about the condition of the electrodes. I fly enough at night in the winter that I don't want to take chances with the condition of the battery so I asked them to install a new one. Hey, it's only money.

The situation with the GPSS switch was more interesting. Dave, the avionics tech, had verified that the switch had failed but they were having difficulty sourcing a new one. I asked for the part number and then queried the collective intelligence of the Cessna Pilots Association on-line forum about finding a switch.

I quickly learned that a new switch (the widget on top in the picture at left) would be available directly from S-TEC for a mere (gasp!) $957.00. That's a little extreme, so I've decided that I'll placard the GPSS as "inop" for a while and see how I like getting along without it.

Subsequently, I've been informed that S-TEC can repair the switches for about $350 (if it isn't completely fried) and I suspect that I'll probably take advantage of that while N631S is down for its annual inspection next spring.

And meanwhile, the weather for this week's trip south looks a bit iffy. As I type this, it's Thursday evening and the Terminal Area Forecast for KBDR looks like this:

KBDR 222330Z 2300/2324 VRB04KT P6SM FEW030 SCT050 BKN150 
     FM230300 08006KT P6SM SCT025 BKN040 OVC080 
     FM230600 06008KT 6SM -SHRA BR FEW007 BKN020 OVC040 
     FM230800 03010KT 3SM RA BR OVC006 
     TEMPO 2308/2311 1SM RA BR OVC004 
     FM231100 01011KT 5SM -RA BR BKN015 BKN030 
     FM231500 35010KT P6SM SCT025 BKN040 
     FM231900 34009KT P6SM FEW025 SCT040
According to this, for tomorrow afternoon I should expect good visibility, a few clouds at 2,500 feet and a scattered layer at 4,000 feet. Conditions to the south are forecast to be a bit better. That's flyable, even with cold temperatures aloft, but the forecast is dependent on some fairly nasty overnight weather clearing out to the east on schedule. Time will tell, and as "Plan B" I have an AMTRAK reservation in my pocket.

Wednesday, December 7, 2011

More About the Fog

Yesterday's post describes an encounter on Monday with dense fog at Bridgeport (KBDR) and the resulting diversion to Waterbury-Oxford (KOXC). It includes the observation that neither the arrival of the fog, nor its persistence, were effectively incorporated in the Terminal Area Forecasts (TAF's) issued for KBDR.

Today I had an exchange on Google+ on the subject with Scott Dennstaedt. Scott is a former National Weather Service (NWS) research meteorologist and the guiding genius behind AvWxWorkshops.com, an excellent source of weather wisdom. He suggested that a comparatively obscure NWS product, the Area Forecast Discussion (AFD), might have helped me to "crack the code" when I was trying to sort out the effects of the fog using the TAF's.

The AFD's are produced by each Forecast Office (Bridgeport is covered by the office at Upton, NY on Long Island) and each AFD includes an Aviation section. The current AFD for the Upton office (OKX) can be seen HERE. Scott was kind enough to send me the Aviation portions of the AFD's that covered the time of interest on Monday.

As I noted yesterday, at 5:00 AM local time Monday KBDR was already fogged in. The TAF extant at that time was predicting that the fog would clear by 9:00 AM (14Z) while the AFD fretted about fog "over much of the area":

350 AM EST MON DEC 5 2011
The forecaster pointed out that the behavior of the fog was difficult to forecast, which I knew well from experience. Still, the TAF came down on the side of the fog being gone by 14Z.

14Z came and went, with no sign of the fog dissipating. An amended TAF valid at 14Z extended the period where fog was considered likely to 15Z, projecting significant improvement thereafter. The Discussion in support of that TAF was still optimistic about improving conditions, but a new AFD issued just before 15Z – shortly after N631S and I had taken off and flown north – incorporated new pessimism:

956 AM EST MON DEC 5 2011
So the AFD's offered through 14Z would not have kept me from departing, while those from 15Z onward might have inspired second thoughts.

As recounted yesterday, N631S and I arrived at KBDR about 1715Z, missed on the ILS Runway 6 approach (when the weather was 1/2 mile and 200 feet), held for a while and diverted to KOXC. We landed there about 1745Z. By that time the 18Z TAF was out and it called for low IFR conditions (a mile and 300 feet) through until 10 AM Tuesday, except for brief periods of slightly better conditions during the afternoon. The supporting AFD had this to add:

1252 PM EST MON DEC 5 2011
This discussion certainly casts a shadow over the TAF. In fact, the ceiling at KBDR went up to 400 feet for about 1/2 hour mid-afternoon (long enough for N631S and I to make an unsuccessful attempt to sneak into Bridgeport) and promptly went back down to 200 feet, there to stay overnight.

The Area Forecast Discussions are a useful tool, giving insight into the forecaster's thoughts and level of confidence. But having reviewed them, I don't think that they would have changed any of my decisions on Monday. The forecaster's multiple references to "low confidence" in aspects of the TAF's do reinforce the notion that the behavior of fog is hard to predict.

Tuesday, December 6, 2011

"On little cat feet"

Sunday evening it all looked good for a Monday morning flight from the DC area to Connecticut. Temperatures aloft were going to be warm enough for me to file for an altitude of 7,000 feet – fairly unusual for December. The Terminal Area Forecast (TAF) for Bridgeport issued at 9:00 PM (02Z) suggested that the weather on arrival at KBDR would be reasonable:
KBDR 050209Z 0502/0524 VRB04KT 1 1/2SM BR SCT030 BKN250
   TEMPO 0502/0505 3SM BR 
   FM050500 20005KT 2SM BR BKN025
   FM050800 VRB03KT 2SM BR SCT005 OVC010 
   FM051400 22005KT P6SM SCT010 OVC040 
   FM051600 22007KT P6SM SCT040 OVC150
   FM051900 22008KT P6SM OVC040=
The plan was to depart soon after 7:00 AM (12Z) for the roughly 2 hour trip. For a 14Z arrival I could expect good visibility, scattered clouds at 1,000 feet and an overcast at 4,000. And conditions were forecast to continue improving. I turned in feeling good about the flight.

My first indication that all might not be well came when, on arising at oh-dark-30 (actually 5:00 AM), I checked the METAR at KBDR:

METAR KBDR 050952Z 00000KT 1/4SM FG VV002 07/05 A3036 RMK AO2 SLP279 T00670050=
This was not good. The fog, without being in the forecast, had come to KBDR "on little cat feet" and with the wind calm (0000KT) it could well sit "over harbor and city on silent haunches" for an unpleasantly long time. And 1/4 mile visibility with an indefinite 200 foot ceiling (VV200) was well below minimums for the Runway 6 ILS approach. Still, the forecast continued to call for improving conditions so I headed for the airport.

By the time I'd pre-flighted N631S, taxied to the fuel island and topped off the tanks, the 12Z TAF was out:

TAF KBDR 051120Z 0512/0612 VRB03KT 2SM BR OVC006
   TEMPO 0512/0514 1/2SM FG OVC002 
   FM051400 22005KT P6SM SCT010 OVC040 
   FM051600 22007KT P6SM SCT040 OVC150 
   FM052200 22008KT P6SM OVC040 
   FM060200 19007KT 5SM BR OVC020 
   FM060700 19008KT 4SM -RA BR OVC015=
Now, in the TEMPO group, the forecaster at least acknowledged the presence of the fog. But conditions were still projected to improve after 14Z (9:00 AM).

But I've been flying in and out of Sikorsky Memorial Airport for quite a few years now, and I've seen fog before. The phenomenon could be very persistent, lingering for hours beyond the time when things were forecast to improve. So I wanted to see an improvement at KBDR before I'd launch in that direction. I'd wait a while.

Things improved a bit at KBDR just before 10:00 AM as the following METAR's show:

METAR KBDR 051452Z 00000KT 1/2SM FG BKN004 OVC008 10/09 A3038=
SPECI KBDR 051459Z 00000KT 1SM BR BKN004 OVC008 11/09 A3038
Visibility had improved to a mile and the ceiling was up to 400 feet. These values were adequate for the ILS approach. In addition, an amendment to the TAF had issued that seemed to promise continued improvement:

KBDR 051347Z 0514/0612 VRB03KT 1/4SM FG VV002
   TEMPO 0514/0515 2SM BR OVC006 
   FM051500 22005KT P6SM SCT010 OVC040 
   FM051600 22007KT P6SM SCT040 OVC150 
   FM052200 22008KT P6SM OVC040 
   FM060200 19007KT 5SM BR OVC020 
   FM060700 19008KT 4SM -RA BR OVC015=
If I got underway, I'd be at Bridgeport a bit after noon (17Z) and the forecast suggested that visibility would be good and the ceiling would be, by that time, overcast at 4,000 feet. Neat! So I fired up N631S and we were off the ground at 1522Z, headed north.

Of course, a forecast is just a forecast. A "guess" – a highly educated guess, but... So as soon as N631S was settled down in cruise at 7,000 feet I checked the new METAR at KBDR:

SPECI KBDR 051515Z 00000KT 1SM BR OVC002 11/09 A3038 RMK AO2=
Rats! The ceiling was back down to 200 feet. This was not what I wanted to see. So I did two things. First, I slooooowed N631S down a lot. Prop RPM down to 2100, fuel flow down to 10 gallons per hour. Perhaps some extra time would allow the happier parts of that forecast to materialize. And second, I started looking for another place to land.
SPECI KDXR 051544Z 22003KT 8SM SCT007 OVC055 11/09 A3037
With eight miles of visibility and a high overcast ceiling, Danbury (KDXR) was a good option. With that Plan "B" in hand, all that was left was to go to KBDR and see what I found there.
To cut to the chase, conditions at KBDR did not improve by the time I got there. N631S and I flew the ILS Rwy 6 approach, advised by the tower that the ceiling was at 200 feet with 1/2 mile visibility – well below minimums. At 300 feet on the glide-slope there was nothing to see but gray. I reported on the missed approach, tower switched me back to New York approach and the controller there said, "Say intentions."

I requested a couple of turns in the hold to figure things out. While the Garmin 530W GPS worked with the S-TEC 50 autopilot to fly N631S around in the hold I checked the METAR's at nearby airports. Waterbury-Oxford (KOXC) was only about 12 miles north and was VFR so that's where we went. N631S and I landed there at 1746Z. (The clip above shows the approach to KBDR, the hold and the flight path up to KOXC. Click to enlarge, if you like.)

So there I was in Oxford and there sat the fog at Bridgeport. I checked the 18Z TAF, which had just been issued:

TAF KBDR 051733Z 0518/0618 VRB04KT 1SM BR BKN003 OVC060
   TEMPO 0519/0523 6SM BR SCT005 BKN060 
   FM052300 21005KT 1SM BR BKN003 
   FM061500 22008KT 4SM BR BKN008=
The forecaster was now suggesting that prevailing weather for the balance of the afternoon would be a mile visibility and 300 foot ceiling, with brief periods of good visibility and a 6,000 foot ceiling. I'd watch the METAR's and hope for a break in the weather that I could use to sneak into Bridgeport.

The break came (I thought) at about 2:00 PM (19Z), when the visibility rose to 3 miles and the ceiling lifted to 400 feet:

SPECI KBDR 051859Z 00000KT 3SM BR OVC004 12/10 A3030 RMK AO2=
OK, that was good enough. I quickly called Flight Service and filed an IFR flight plan for KOXC to KBDR, direct.
In short order, N631S and I were back in the air and headed for KBDR. The New York Approach controller asked if I had ATIS "November" at Bridgeport, which I quickly picked up. It was consistent with the last METAR I'd seen. So far, so good. The controller began to issue vectors to me for the ILS Rwy 6 approach (see clip above, at left). About then I heard another aircraft on the frequency mention "Tango at Bridgeport". Uh-oh. That could only mean a later ATIS incorporating a change in conditions. I went back to the Bridgeport ATIS frequency and heard, "Visibility one and three-quarter miles, sky condition overcast 200 feet." Back below minimums. This wasn't my day.

The controller asked me if I had gotten "Tango" and I said, "Yes, and it's depressing." She said, "A King-Air just missed there...do you want to try it anyway?" I declined and asked for a vector back to KOXC, which still enjoyed excellent visual conditions.

That wrapped up aviating for the day. I arranged with the FBO to park N631S overnight and, with another pilot who'd diverted from KBDR, rented a car for the short drive to Bridgeport. That turned out to be a good choice, as for the rest of the day the ceiling at KBDR never got above 200 feet. The weather at this writing (Tuesday evening) continues to be poor. But this weather system will pass through tomorrow and Thursday is forecast to be VFR. That's when I'll find my way back to Oxford to retrieve N631S.

Tuesday, November 22, 2011

"It's the Third Approach that Kills You"

One of the "Ancient Pelicans" hanging around KBDR shared the wisdom in this post's title with me soon after I got my Instrument Rating. His theory was that if you were shooting an instrument approach for the third time you were tired, and frustrated, and maybe getting a little thin on fuel...and thus perfectly set up to push things a bit too far. And your funeral would be held on a sunny day.

So, he advised, go ahead and take it around for a second try. But if the second approach is a miss...go somewhere else where conditions are better. I thought that was pretty good advice.

That advice came back to me this afternoon, after the folks at FlightAware.com sent me an e-mail notification about a friend's flight. I have the "N" numbers of several friends' airplanes set up for the service and one of them had departed Lancaster (KLNS) for a flight to Manassas (KHEF). I clicked on the link to see where he was.

He'd departed KLNS shortly before 2:00 PM, launching into some fairly significant weather. By the time I brought up the web site (just about 3:00 PM) I expected he'd be close to his destination. But I found him 20 miles north of Manassas, on the ILS approach to Runway 17 at Leesburg (KJYO). Given the weather depicted on the screen, this would likely be an interesting approach. I pulled up the METAR:

KJYO 221955Z AUTO 00000KT 4SM RA BKN002 OVC017 10/10 A3009
That was not at all a sure thing! Ceiling reported at 200 feet, and the Decision Height for the approach at 250 feet AGL. I refreshed the screen a couple more times, watching the airplane icon near the airport location, and the altitude readout roll down. Then, it started to roll up, the speed readout increased and the icon turned away. Missed approach.

My friend flies a Cirrus SR-22, and is a fine instrument pilot. But this was no-kidding-around weather – the Real Deal. I had to hang around to watch the story unfold.

The airplane icon moved off to the north, then turned back toward KJYO. Vectors for a second approach. Back to the final approach course, speed reduced, altitude decreasing...and then increasing. A second missed approach! And the advice of the Ancient Pelican, gone West years ago, arose in my mind. Get out of there, my friend. You don't have to be in Leesburg today.

At left, the track as shown on FlightAware.com to this point. (Click to enlarge.) You can see the first approach, the turn outbound and then back in for the second ILS. And finally, the airplane icon outbound again to the Northwest. "Say intentions."

I will admit to a sigh of relief when he turned to the northeast and left KJYO well behind. Having decided that two tries at that ILS were quite enough he was headed somewhere else. I watched to see where he'd go.

The track bent to the east and then around to the southwest. He was lining up for the Runway 23 ILS approach at Frederick (KFDK). As the icon representing my friend's airplane approached KFDK I pulled up the METAR that was on offer there:

KFDK 222051Z AUTO 36005KT 7SM +RA SCT004 BKN009 OVC023 08/08 A3009 RMK AO2 P0002
Despite the heavy rain (+RA) this looked better. Good visibility and a broken ceiling at 900 feet. I watched, refreshing the display periodically, as the tiny blue airplane moved over the airport symbol...and stopped. Safe on the ground. (Below, the rest of the track courtesy of FlightAware.com)

Of course, the outcome was never seriously in doubt. My friend is a capable aviator, well qualified to deal with these conditions. But I'm sure he had some adrenalin flowing and he probably sat in the airplane for a minute after shutting down, while some tension dissipated.

As for me, I applauded the good judgement he exercised in avoiding a third approach to KJYO. Perhaps somewhere my other friend, the Ancient Pelican, is smiling.

Tuesday, November 8, 2011

Children of the Magenta Line

The video embedded below was posted on the AvSig online forum by a friend. It's a presentation by a senior American Airlines training Captain on the subject of automation dependency (a subject I've commented on before). For my friends out there who fly aircraft that are able to let the GPS navigator drive the autopilot – well, you really ought to invest the 25 minutes in watching this; every time he says "FMC", substitute "GPS".

Automation Dependency from Bruce on Vimeo.

Sunday, November 6, 2011

Parsing the Regs

The previous post discussed the "inop" status of the beacon that sits atop N631S's vertical stabilizer. In summary, (a) as of Friday morning it was not working at all; (b) the maintenance folks were on the case; and (c) I believed it to be a "no-go" item that would need to be fixed if I wanted to make my weekly trip from Connecticut to the DC area by airplane rather than AmTrak.

Well, perhaps not so much.

Midday Friday I went over to Three Wing Flying Services and talked with Tony and Jared. Tony had the bad news: "We found a short, and your lamp is shot...and we don't have a 14 volt lamp in stock." Jared offered the good news: "You've got strobes, right? As long as you have strobes, you don't need the beacon."

Really? I needed to think about this a bit. This was one of those times when it would be necessary to see what the regulations said, and to consider what the regulations mean!

The applicable regulation is found in Title 14 CFR Part 91 Subpart C (Equipment, Instrument, and Certificate Requirements) Section 91.209 (Aircraft lights), which says in relevant part:

No person may:...(b) Operate an aircraft that is equipped with an anticollision light system, unless it has lighted anticollision lights. ...

N631S is in fact "equipped with an anticollision light system", so that part of 91.209 is applicable. In normal circumstances, that system is comprised of the red flashing beacon atop the vertical stabilizer and the white wingtip strobes. If the beacon is "inop" but the strobes are working just fine, then the aircraft complies with the requirement that it "ha(ve) anticollision lights" when being operated. So far, so good.

Here's an excerpt from an on-line forum called TheCFI.com that shows at least one other person using the same logic to arrive at the same conclusion:

Beacon/Rotating Beacon vs Anti-Collision Lights
by jdkiger » Tue Aug 19, 2008 10:02 am

A recent discussion at my flight school resulted in very different opinions in understanding of what is required. Not quite addressed in past questions on this forum. Our situation is: Aircraft has wing tip strobes/anti-collision lights in addition to a vertical stabilizer mounted aviation red/white strobe (individual power supplies). With the strobe out on the vertical stabillizer inop, placarded as such. Required log book entries documented. Is the aircraft airworthy? Many suggest that since the wing tip strobe/anti-collision lights are operating the aircraft meets the requirements to be airworthy. How about it?


by midlifeflyer » Mon Aug 25, 2008 7:50 am

This is pure guesswork on my part since I've never seen anything from the FAA on it...

91.209(b) says "an" anticollision light system (so do the applicable provisions of 91.205). If the aircraft has two different ones that each comply with TSO C96a (and whatever other requirements there might be), one should be sufficient for compliance with 91.209(b).

That is, of course, assuming that the other requirements of 91.213 regarding flight with inoperative equipment are met.

Like I said, pure guesswork.

Finally, I recall that the previous airplane in my life, N82953, a 1981 Piper Archer II, came from the factory with wingtip strobes and no rotating beacon. And it was just fine in that configuration. So in the end, I concluded that N631S was indeed airworthy with the beacon placarded "inop" (as required by 91.213) and the strobes fulfilling the requirement of Section 91.209 for operating anticollision lights. I could make my flight to DC without transgressing the bounds of the regulations.

Three Wing is ordering the parts needed to restore N631S's beacon to operating status, which work will be done during the coming week.

Friday, November 4, 2011

First, the Good News...

The weather forecast is fine for a flight this afternoon from KBDR down to KVKX in the DC area. While temperatures aloft will be below freezing (after all, it is November), the skies should be clear or at least ceilings should be quite high. Thus, icing ought not to be at issue.

On the subject of ceilings, I've been enjoying a new (to me) weather data site, the High Resolution Rapid Refresh (HRRR) model from NOAA. (A "hat tip" to Jim Fallows for pointing this one out on his blog a couple of days ago.) It appears to have evolved from the highly regarded Rapid Update Cycle (RUC) model and includes excellent forecasted ceiling graphics like, for example, this:

That graphic depicts ceiling heights forecast for 23Z this evening and, as you can see, it's an optimistic picture. And, the Terminal Area Forecasts (TAF's) are consistent with it. So it's all good, but...

Now, the Bad News!

This morning, when I went to the airport to stow my bag and pre-pre-flight N631S, a problem cropped up. The flashing beacon (that red flasher on top of the vertical stabilizer) neither flashed nor beacon-ed. I'd expect to be flying after sunset, and the rules say that if you have anti-collision lights installed they have to work. So I look at this as a "no-go" item. My friends at Three Wing Flying Services are working on the problem. If it's an easy fix, I'll be good to go. If it turns out to be hard or to require a part that isn't in stock, then I will find myself on AmTrak this weekend.

Saturday, October 29, 2011


The terminal area forecast for KDCA that issued at 18Z yesterday (recovered from the marvelous OgiMet site) had me motivated to get N631S and myself airborne and headed toward the DC area without undue delay. The lines for "FM2100Z" and "FM2300Z" are relevent:
TAF KDCA 281740Z 2818/2918 06005KT P6SM SCT140 SCT170 BKN250 
FM282100 08004KT P6SM VCSH BKN060 OVC090 
FM282300 10004KT P6SM -RA FEW020 SCT040 OVC080 
FM290300 07005KT 6SM -RA BR SCT020 OVC030 
FM290600 03006KT 5SM -RA BR SCT015 OVC025
FM290900 01007KT 6SM -RA BR FEW007 OVC011 
FM291100 36009KT 4SM -RASN BR SCT008 OVC012 
FM291500 35011G18KT 3SM -RASN BR FEW005 BKN008 OVC011 
FM291700 35015G24KT 1SM -SN BR BKN004 OVC007=
The 21Z line in the TAF for KBWI was about the same. I could get past Baltimore with a broken ceiling at 6,000 feet (BKN060) and for arrival I could work around "showers in the vicinity" (VCSH). But the freezing level was going to be somewhere around 3,000 feet which made the forecast for 23Z, calling for light rain (-RA) and an overcast at 3,000 (OVC030) a "no-go" condition. My conclusion was that I'd better be on the ground at Potomac Airfield (KVKX) well before 23Z (7:00 PM EDT).

Conditions were quite good departing KBDR and stayed that way until I reached the Allentown Approach airspace. From that point onward the overcast was solid and at 8,000 feet it looked like I could reach up and touch it. On the positive side of the ledger, winds aloft were light and I was making good speed over the ground (mostly between 130 and 140 knots).

I had to smile looking at the screen showing the NEXRAD returns when N631S and I were abeam of Allentown. The Outside Air Temperature was 27 degrees, and to look at the green area ahead, you might think that there was a problem in the making. NEXRAD was indicating lots of moisture, and that added to sub-freezing OAT's can mean ice! But, if you go ahead and click on that screen shot, you'll see a picture taken seconds later that shows what I was seeing straight ahead through the windshield.

The hint is in the color of the triangles next to the ABE and RDG airport symbols. Blue means good VFR weather, and that held up all the way across Baltimore and into KVKX. This was the METAR in effect as I crossed the BAL VOR:

KBWI 282054Z 11005KT 10SM FEW060 BKN110 OVC150 09/M02 A3021 RMK AO2 SLP231 T00891022 53001\
And this was the one for Andrews AFB (KADW) as I was landing a couple of miles away at KVKX:
METAR KADW 282055Z AUTO 11003KT 10SM FEW075 SCT090 08/M01 A3022 RMK AO2 SLP236 T00791007 53002 $=
N631S was snug in its hangar well before the rain began, about an hour after the TAF had forecast:
KADW 290016Z AUTO 07003KT 10SM -DZ FEW024 BKN044 OVC055 07/00 A3021 RMK AO2 DZB0016 SLP235 $

Monday, October 17, 2011

Into the Darkness

Hindsight being consistently 20-20, I now find myself looking back on last Friday's flight from Bridgeport (KBDR) to Potomac Airfield (KVKX) with acute interest. The interesting bits came in three distinct parcels; I'll describe them in turn.

Part I

The previous post reviewed my planning for the flight, and included an off-hand comment that it's the time of year when one needs to think "less about, 'Will there be convection issues?' and more about 'Will there be ice?'" Famous last words.

As N631S and I were taxiing for departure, the controller advised that ATC was not providing IFR releases for aircraft headed west or south "due to weather." I said I'd park and wait it out. On the way back to the tie-down I took the screen shot at left, showing the weather that was causing the problem.

I was aware that there was significant weather in that area, but I had felt I could depart and work with ATC to find a route through the line or at worst, turn around and return to KBDR. But that scheme didn't work for ATC! In the busy New York Approach airspace, I guess that there isn't time to work individual aircraft through a line of convection. They just shut the routes down until the weather improves.

So, N631S and I sat on the ramp, checking in with the tower every 15 minutes for an update. After an hour and a half, the answer came back as, "Things are improved over by Sparta...you'd better get taxiing." Which we did!

The screen shot at left was taken soon after departure and shows the break in the line that we were aiming for. With just a few vectors for spacing, we were on our way westward. There were some cloud buildups to go through that looked a little intimidating, but the NEXRAD radar display showed little precipitation and there was no indication of lightning. And in the event, the clouds contained nothing worse than light turbulence.
At left, the view at 8,000 feet, coming out of the far side of that line of weather near the Sparta VOR (SAX). You can see the glow of sunset, a result of the delay in departure from KBDR. I hadn't expected to be logging night time on this trip but it was working out that way.

Part II

In looking at the weather forecast for this flight, it was clear that there might be some flirtation with ice. And near Allentown at 8,000 feet N631S and I found ourselves in the cloud layer with the outside air temperature (OAT) coming down. I wanted to stay at 8,000 as long as possible because the winds were more favorable there than at 6,000. Despite a true airspeed of about 140 knots, speed over the ground was only about 110 knots. Lower, the wind would be more directly "on the nose" and the headwind component stronger. I watched the declining OAT until it reached 34°F, and then asked Allentown Approach for a descent to 6,000. And as expected, about 7 knots of ground speed went away. But that altitude was below the clouds and significantly warmer.

Except for needing to be vectored around an isolated patch of convective weather just north of Lancaster, the balance of the en route portion of the flight was uneventful.

Part III

As had been forecast, the surface winds in the DC area were strong and gusty. And, as expected, the winds at KVKX were moderated by the field's location in a valley. Still, there was enough wind (reported as 7 knots from 260°) to make Runway 24 the clear choice. My final controller from Potomac Approach asked if I had the weather at KVKX and I replied, "Yes, I've picked that up; looks like it'll be Runway 24 tonight."

That elicited an offer that I couldn't refuse. Andrews AFB, which lies about 5 miles northeast of KVKX, was more or less between my position and the approach end of runway 24. I could get a turn toward the airport passing just south of Andrews, provided that I agreed to timely cancellation of IFR (since I'd wind up below Approach's Minimum Vectoring Altitude). Visibility was good, so I said, "Sure, we can do that." To which the controller said, "Proceed direct to VKX while I talk to Andrews."

A few minutes later I was at 1,500 feet, essentially crossing east to west over the approach lights of Andrews' Runways 1R and 1L. I was set up on a left base for 24 at VKX. Having cancelled IFR when I had the beacon in sight, I reported the runway in view and was released by the controller. N631S rolled out on about a 3 mile final.

It was a bit after 8 PM local time, and completely dark. Approaching KVKX from the northeast – something I'd never before done at night – offers only the most sparse ground lighting. The runway lights are clearly visible and welcoming, but the intervening terrain is something of a "black hole". The area is basically flat and featureless and I was down at about 1,300 feet to stay well below the floor of the Class B Airspace.

We've all read the training materials on visual illusions. We've been told about the dangers of the "black hole approach." (Avoiding Black Holes by Dale Wilson gives a good overview.) But now I was about to have the experience.

The visual approach aid for Runway 24 is a two-light VASI (Visual Approach Slope Indicator). Red beside red means you're low. White beside white, you're high. Red with white is just right. As I looked out into the dark night, the VASI was stubbornly red with red. Yet everything else about the sight picture had my ground-dwelling brain screaming at me, "Too high! You're too high! Get down!" I had to consciously remind myself, "It's an illusion. Do not descend. Trust the VASI." I was applying that first rule of IFR flight – trust your instruments! And soon, one of the red lights turned white and I started a descent toward the runway.

The landing itself was uneventful, and I was left reflecting on how a VFR-only pilot, trained to trust his eyes, could so easily be trapped by what I'd just experienced. It's a sobering thought.


Two nights later. Sunday, about 8 PM, N438CP – a Cirris SR-22 – was on a visual approach to Runway 26 at Danbury (CT) Municipal Airport (KDXR). The weather was good. I've flown into Danbury on occasion and can state that the terrain surrounding the airport is interesting at the best times.

The approach to 26 is over a residential neighborhood, presumably fairly dark. About a half mile short of the runway, at a point approximately 160 feet above the threshold elevation, the Cirrus flew into the terrain (reportedly where the red dot appears at left). The pilot, sole occupant of the aircraft, was fatally injured. And now I wonder...was he a victim of the siren call to fly lower that I was fortunate enough to be able to ignore?

Thursday, October 13, 2011

It Looks Like Summer's Over

A friend says that there are two seasons here in the Northeast: "Leaves On" and "Leaves Off". We're now well into the transition to the latter, and the times call for a different approach to flight planning. It's now less about, "Will there be convection issues?" and more about "Will there be ice?"

The plan for tomorrow, as usual on a Friday, is to depart Bridgeport (KBDR) late in the afternoon for the flight down to the DC area (KVKX). I expect that my clearance will take N631S and I west to the Sparta VOR (SAX) then south to Solberg (SBJ), west again to the Allentown, PA area, south across Reading, Lancaster and Baltimore, MD, then on into my destination. The first question is, "What's the big picture look like?"

We've got a surface low just north of Lake Huron, with an occluded front trailing off to the southeast. The map (from the NCEP Hydrometeorological Prediction Center site, reflecting the forecast for 00Z Saturday, i.e., 8 PM EDT) depicts an area of showers covering much of New England and New York along with parts of New Jersey and Pennsylvania. Maryland and Virginia are not included. So, I can may get wet on departure but the arrival at KVKX is likely to be dry.

The latest Terminal Area Forecast (TAF) for KBDR (at 00Z Friday, 8 PM EDT, from the AviationWeather.gov site's TAF page) indicates that the rain will stop about 1 PM tomorrow afternoon and the ceiling will be broken at 2,000 feet – not so bad! Here's the TAF:

KBDR 132342Z 1400/1424 06007KT 2SM BR OVC007 
     TEMPO 1400/1402 1SM -DZ BR OVC006 
     FM140400 10007KT 3SM -RA BR OVC003 
     TEMPO 1409/1412 1SM BR 
     FM141400 14010KT 5SM -RA BR BKN008 OVC012 
     FM141700 15012KT P6SM BKN020 
     FM142200 20011KT P6SM SCT030 BKN100

For another indication of the flight conditions to be expected, I can look at the relative humidity (RH) aloft. The chart at left (collected from the NCEP Model Analysis & Guidance site), also valid for 00Z, shows the RH for the 850 millibar level of the atmosphere (or, about 5,000 feet). Most of my expected route is covered by the lighter green, indicating RH of 70% to 90%. In that range, I can probably expect nice, juicy clouds. (An RH above 90% says that rain is very likely.) I'll be starting out at 8,000 feet and then probably descending to 6,000 somewhere in Pennsylvania, so it's a good bet that I'll get to log a significant bit of actual instrument time.

The really important question is whether icing is a hazard. Given the expected RH data, it's pretty clear that if the Outside Air Temperature (OAT) aloft is below freezing then airframe icing is a real possibility. Let's look at the forecast.

Here's the forecast (from the AviationWeather.gov Winds & Temperatures page) for 00Z tomorrow night, showing isotherms at the 725 Mb level (about 9,000 feet). At an altitude of 8,000 feet (required to stay above the Newark arrivals) N631S and I ought to see OAT's a Celsius degree or two above those depicted. It might be a bit close, but conditions ought to be acceptable going over to Sparta and down to Solberg.

Once in Allentown Approach airspace (i.e., about at the Pennsylvania border), Newark arrivals will no longer be a factor and I'll be able to request a descent to 6,000 feet. (The chart at left shows 00Z temperatures at 800 Mb, about 6,000 feet.) That will be well below the freezing level and should be the end of concerns about icing. The rest of the trip, in warmer air and toward improving conditions, should be uneventful.

It will not, however, be quick. At left, the 00Z forecast winds at 9,000 feet (and the forecast conditions for 6,000 to 8,000 feet are similar). As you see, there will be substantial headwinds to deal with. According to FlightPlan.com, the average headwind component for the flight will be 18 knots and the expected time en route is 2 hours + 24 minutes – a rather tedious trip!

As for arrival conditions, the TAF for nearby Washington National Airport (KDCA) is suggesting that from 20Z (6 PM) there will be showers in the vicinity with generally good visibility and scattered clouds at 1,500 feet under a broken ceiling at 5,000.

KDCA 132335Z 1400/1424 12008KT P6SM VCSH BKN030CB 
     FM140600 18005KT 5SM BR BKN008 OVC015 
     FM141300 22007KT P6SM VCSH BKN015CB 
     FM141800 26010G18KT P6SM SCT015 BKN050 
     FM142000 27012G24KT P6SM VCSH SCT015 BKN050
If one of those "showers in the vicinity" (VCSH) chooses to park right over the airfield, then the RNAV Rwy 6 approach may be necessary but there's nothing to suggest any real difficulty getting in. The forecast wind (for KDCA, 12 knots out of the west, gusting to 24 knots) looks a bit energetic, but the field at KVKX is nestled in a valley and the winds there are rarely as strong as forecast at nearby airports.

So, to summarize:

  • A departure into fairly low, possibly showery conditions;
  • Some near-freezing OATs possible in northwestern New Jersey at 8,000 feet;
  • Steady, fairly strong headwinds throughout;
  • Reasonably good arrival conditions, with a possible shower and perhaps gusty winds.
In short, a fairly typical Fall IFR flight.

Thursday, October 6, 2011

Steve Jobs

I have never owned an Apple product. The controlling, "we-know-what's-best-for-you" ethos that emanates from the Cupertino mother ship was not something with which I can deal. But that doesn't mean I can't recognize just how very good Steve Jobs was at what he did.

He was a unique amalgam of rare properties, combining the design genius of a Frank Lloyd Wright with the marketing savvy of a Lee Iacocca. Of the Jobs quotations that have been sloshing around the online world for the last 18 hours the one that goes to the heart of his brilliance is this:

"In most people's vocabularies, design means veneer. It's interior decorating. It's the fabric of the curtains, of the sofa. But to me, nothing could be further from the meaning of design. Design is the fundamental soul of a human-made creation that ends up expressing itself in successive outer layers of the product or service."
Looking at the phenomenon that is Apple, after sloughing off the non-essential, it is all about product design. In the beginning was the design and from the design all good things flowed. The designs are perfect, with nothing lacking that is needed and nothing present that is not necessary. They are like Hemingway's prose, like the music of Mozart, like a Frank Lloyd Wright house. That was Steve Jobs' genius – that he could so order life that such glorious artifacts emerged as a matter of course.

He did not save lives through his work, nor feed the hungry nor cure the sick. But through his art he taught us how to make our interaction with a technology-intensive world richer and more productive. For that he will long be remembered and honored. And his like will not be seen again in our time.

Monday, September 26, 2011

Reflecting on Reno

It's been difficult for me to sort out a number of conflicting impulses in the aftermath of the crash of Galloping Ghost at the National Championship Air Races in Reno, NV. My initial reflexive reaction was to recoil from the pointless tragedy. So much death and destruction for so little purpose! In the wake of the mishap, I would not have protested a decision to end these events forever. And yet...

In another context, these words have appeared in this venue:
"...it is very good for the character to engage in sports which put your life in danger from time to time. It breeds a saneness in dealing with day-to-day trivialities which probably cannot be got in any other way, and a habit of quick decisions."
This was written by Nevil Shute Norway in his autobiography, Slide Rule. And he did engage in such sporting activities: offshore yachting, motor racing, and aerial exhibitions. Air racing fits neatly into this context and has, in fact, a long heritage in aeronautical development.

Not long ago, I acquired a copy of The Conquering Wing by Grover C. Loening. This author was a giant figure in the early decades of American aviation. He managed the Wright Aircraft factory for Orville Wright, founded his own aircraft manufacturing firm, and made important contributions to aeronautical design. But in this book, published in 1970, he chose to write a work of fiction to convey what aviation was like in the U.S. prior to the First World War. Air racing is central to Loening's plot as it was central to pushing the bounds of technology before the imperatives of combat took over that role. And Grover Loening was there!

The names of the great air race trophies resonate with us. The Thompson Trophy, the Bendix Trophy, the Schneider Trophy. In pursuit of these prizes, the great pilots and engineers advanced the state of the art. Who can say what ships "the Few" would have had to launch against the onslaught of the Luftwaffe if Spitfire designer Reg Mitchell hadn't the opportunity to design the Supermarine S.6B (and its immediate progenitors) for the Schneider Cup?

The National Championship Air Races in Reno have carried on this rich tradition – but they have not fulfilled the role. Aeronautical engineering has passed by the air race. It no longer can serve as a technology driver. The only role left to it is commemoration of the glory of a bygone era. Who can say that isn't enough, for the zealous participants who willingly assume the obvious mortal risks?

But there must be a corollary to Shute's endorsement of danger-laced sport, stipulating that the dangers must not, beyond irreducible minima, devolve upon non-participants. In many cases – mountaineering, spelunking, white-water kayaking, as examples – all of the risk is assumed by the participant. But in some cases the risk to life and limb flows outward to others. For example, there has been controversy in the offshore yacht racing community over races that were started in awful weather, with a foreseeable likelihood that air-sea rescue teams would be called on to risk their lives to recover crews in distress. And now, there is controversy in the air race community, and in the wider community surrounding the races, about the risks assumed by spectators. This issue has been confronted by other motor sports and by the related air show community. Now the air race world will have to adapt.

The argument that spectators at high-risk events have somehow "volunteered" to accept the risk by choosing to be present does not hold water. It is the obligation of the participants and the event organizers to so arrange things that the dangers to which spectators are exposed are mitigated to the greatest degree possible. No "hold harmless" printed on the back of a ticket can change this.

Motor racing and the air-shows have implemented serious risk-mitigation efforts, triggered in each case by horrific mass-casualty mishaps. Motor racing changed forever after the 1955 LeMans Gran Prix accident. Thereafter, improved barriers, track reconfiguration and performance limits (e.g., restrictor plates) led to a profound reduction in spectator risk.

For the airshow world, the triggering event was the disastrous accident at the 1988 Ramstein Airshow in Germany. Three aircraft of the Italian Frecce Tricolori demonstration team crashed into the crowd causing 67 fatalities and hundreds of injuries on the ground. This led to regulations requiring designated buffers (of sizes that depend on aircraft performance) and a ban on aerobatic maneuvers that direct kinetic energy toward the spectators. In the U.S., each airshow functions under an FAA waiver that codifies these requirements.

An air race is a somewhat different animal. Because of the oval course configuration, the notion of "no energy directed toward the spectators" has been regarded as impractical for air races. (At Reno, the Grandstand is located in the apron area across the runway at the "bottom" of the oval course (left).) Thus, the tragedy at Reno was made possible.

It has been suggested that the spectators could be relocated inside the oval course. This notion has several drawbacks: (1) The cost of relocating the race's infrastructure could be prohibitively high; (2) much of the action would take place behind the spectators; and (3) the dimensions of the oval courses for the smaller, slower classes are confining.

There may be another alternative; one that would require the abandonment of two-dimensional thinking.

Keep the Grandstand and the Start/Finish line where they are. Run a "lap" that begins with a straight course from left to right across the front of the crowd (with an appropriate buffer distance ) at an altitude no lower than 1,200 feet AGL, After passing the crowd, there would be a tear-drop course reversal beginning with a turn away from the crowd and incorporating a descent to an altitude no higher than 1,000 feet AGL and then a second opposite direction straight pass in front of the stands. At the end of the second straight, a course reversal in the vertical plane (an "Immelman") to re-establish the aircraft on the initial straight.

This would give the spectators a good show, require a bit more of the pilots than "fly low, go fast and turn left", and enhance safety by ensuring that no kinetic energy is directed toward the crowd.

I can claim no qualification to justify my making suggestions to the air racing community at this sad time. But perhaps this sort of "out of the horizontal plane" thinking can help to bring about practical changes that will allow the Air Race tradition to continue and make the loss of Jimmy Leeward and ten others the impetus for a new era of reduced risk at Reno.

Jimmy Leeward – Gone West, 16 September 2011

Saturday, September 10, 2011

Muddy Waters

The flight from Connecticut to the DC area yesterday was thoroughly uneventful – the best kind! The adverse weather that came north with the remnants of Tropical Storm Lee had moved on leaving no trace aloft. But it's another matter at zero feet AGL.

Here (left) a look at the Hudson River from 8,000 feet, a few miles north of the Tappan Zee Bridge. Normally the entire river is the color of the waters seen at the lower left of the image, in Croton Bay. The bay is protected by the Croton Point peninsula. Outside this embayment, the river is a rich, silty brown from the massive upstream runoff that the rains of the past week generated. Upstate New York experienced almost as much flooding as Vermont and many small rural streams turned into raging torrents. Now, the Hudson is carrying the effluent to the sea.

About an hour later, this was the view of the Susquehanna from 6,000 feet. The stream flows from the bottom of the image toward the top and is usually a steely blue-gray. But with the upper Susquehanna reaching flood-stage and beyond at Binghamton and Wilkes-Barre, it isn't surprising to see it turned brown by a burden of silt headed for the Chesapeake. It may be a while before the region's rivers recover their accustomed colorations. Meanwhile, it's enlightening to see the changes induced by Mother Nature from the perspecive of a small aircraft a mile or so up.

And what happens to all that silt? Look at this NASA Landsat 5 image from 2 September. It shows (from a somewhat higher perspective) the Connecticut River depositing silt generated by runoff from Hurricane Irene into Long Island Sound. (Click here for a full description of the image.) That used to be a large part of Vermont, right there.

Friday, September 9, 2011

Today at KBDR

The Collings Foundation WWII bombers mentioned in the previous post seem to have made it to KBDR despite the wet weather of the week. This morning they were parked on the ramp.

Witchcraft (below) is a Consolidated B-24J Liberator, one of very few left in airworthy condition.

Nine-O-Nine (below) is a Boeing B17-G Flying Fortress, a type that became more rare earlier this year when Liberty Belle burned after a forced landing (story here).

Along with Betty Jane, the P-51C Mustang, they are heading up the road to Waterbury-Oxford Airport (KOXC) for the weekend.

Tuesday, September 6, 2011

Lee's Leftovers

Tropical Storm Lee arrived at the Gulf Coast a couple of days ago and has been working its way inland, losing its classic cyclonic form and devolving into a widespread, northeast-bound rain event. The precipitation field encroached on the DC area last evening and this morning N631S and I had some moisture to deal with on our trip north.

All in all it wasn't so bad. In and out of the showers all the way, with some rising to the level of "moderate." No turbulence to speak of, and for most of the trip a healthy tailwind. Just your basic rainy-day IFR flight, including a nice stretch over New Jersey (left) where the sky brightened and the rain stopped.

This pleasant interlude continued to the Coyle VOR (CYN), when McGuire Approach asked for a descent from 7,000 feet to 5,000 which was back in the schmoo...where we stayed until the final New York Approach controller took us down to 3,000 feet east of JFK. The flight ended with an easy ILS approach through a layer of few clouds at about 1,300 feet to BDR's Runway 6.

Having covered and tied down the airplane, I was walking toward the FBO when I saw the lovely machine pictured below, tucked into a hangar and out of the weather. That's Betty Jane, the Collings Foundation's North American P-51C Mustang, s/n 42-103293.

The aircraft has been modified to include a second seat with dual-controls (located where the fuselage fuel tank was). She's here for a few days – and her compatriot B-17G Flying Fortress and B-24J Liberator are also expected – for a few days of tours and warbird rides. It will be unfortunate if the wet weather forecast for the next few days dampens the event.

Monday, August 29, 2011

An Eerie Silence

Hurricane Irene has hurried off to points north leaving an array of inconveniences with which to deal. But life goes on, so this morning N631S and I were airborne and headed toward Connecticut as we are nearly every Monday. Today's trip was a quick one, as Irene's parting gifts included a tailwind at 7,000 feet of about 15 knots. This let me reduce the prop RPM to 2150, lean the fuel flow to 9.7 gallons per hour, and still make about 145 knots over the ground.

The air traffic control frequencies seemed quieter than normal, but the silence got downright spooky in New York Approach airspace. Transiting some of the busiest airspace in the world, it seemed like N631S and I were alone. On a normal day, the flight path follows airway Victor 1 from New Jersey directly over John F. Kennedy International Airport, then off to the northeast along Victor 229 to Bridgeport. Today was not normal.

Just clearing Sandy Hook, the controller asked, "Skylane 31 Sierra, would you like to go direct Bridgeport at this time, or wait until after JFK?" There just wasn't any traffic to interfere with! I responded with, "31 Sierra will take direct Bridgeport," accepting an extra mile or two of flight over water. This moved my track off to the east a few miles, allowing me to snap this picture of a nearly empty JFK. Click on it to enlarge and you'll see very few aircraft.

Flooding from Irene's torrential rains had caused the closure of Sikorsky Memorial Airport (KBDR) but one runway had re-opened at 0830 local time. Having been cleared for the visual approach to Runway 24, I contacted the Tower and the controller advised me to exercise caution due to ponding near the runway and extensive bird activity. Apparently, our feathered friends are enthusiastic about the new-born pond!

As I was about to turn base, toward the runway, the controller said, "31 Sierra, if you can give me a right 360 there, I'll get a truck to go over there and scare away the birds." I said "Wilco," and set up a standard two-minute turn while "Rescue 4" drove past the pond making noise. Finishing 270 degrees of the turn put me onto the base leg of the approach. I saw the pond, and the birds now returning to it. So I "landed long", passing over the birds and touching down well past them. It's to be hoped that the waters will soon subside, and the birds will return to their more usual environs.

Saturday, August 27, 2011

Ahead of Irene

Yesterday afternoon when I arrived at KBDR, N631S was one of the few aircraft on the ramp. With Hurricane Irene on the way, most others were either in hangars or flown away to safer locales. Earlier in the day my friend Jared Gowlis from Three Wing Flying Services had called me just to be certain that I planned to fly out. The precautions are well advised, as conditions anticipated for Sunday at KBDR are downright unpleasant. Here's the 18Z TAF issued on Saturday, 26 August:

KBDR 271939Z 2720/2818 10012KT 5SM -SHRA BR BKN004 OVC008 
     FM272300 10015KT 3SM RA BR OVC006 
     FM280200 09030G38KT 1SM +RA BR OVC006 
     FM280600 10040G49KT 1SM +RA BR OVC004 
     FM281100 10050G60KT 1SM +RA BR OVC004 
     FM281500 09060G72KT 1SM +RA BR OVC004
Yes, that last line says sustained winds of 60 knots (69 mph) with gusts to 72 knots (83 mph) from 11:00 AM until at least 2:00 PM tomorrow. Not fit for man nor beast nor unprotected airplane!

So N631S and I got underway for the trip south to KVKX, Potomac Airfield, just across the river from home in Alexandria. The clearance was what I've come to expect: vectors to SAX V239 SBJ V30 ETX V39 LRP V93 BAL Direct.*

Aside from dealing with moderately strong headwinds, the trip proceeded uneventfully for the most part. About an hour after departure I had a look at the NEXRAD display on the Garmin GPSmap 396, zoomed out to a wide view, to see where the leading edge of Irene's precipitation shield was. It was well to the south – nothing to be concerned about on that score. The only weather in Virginia was a few isolated thunderstorms unrelated to the approaching cyclone.

Later, still over Pennsylvania with an hour to go, I took a look at the situation near KVKX, my destination. Ah, there was a bit of a surprise! A couple of those summer cells had set up shop in the immediate vicinity of where N631S and I wanted to go. And with the storm on the way, this would be a bad night to have to divert. I watched those cells for a while – they were stubbornly disinclined to move away. The only good news was that there appeared to be no weather immediately over KVKX.

Just south of Baltimore, with Andrews AFB abeam, the rain was clearly visible. There still seemed to be no weather over KVKX and the approach to Runway 6 looked clear. The Potomac Approach controller asked if I wanted to try a visual approach or would I like the RNAV Rwy 6 instrument approach. I considered the visual too chancy, given the cells of weather in the area so I requested the RNAV approach and loaded it into the GNS-530W.

Approach passed along a couple of weather avoidance vectors as they routed me around the intervening precipitation and toward WOBUB, the Initial Approach FIX (IAF) for the RNAV approach. I was asked whether I would like Vectors-to-Final for the straight-in approach or the full approach with the procedure turn. Under the circumstances, it was a good idea to get N631S on the ground with all deliberate speed, so I requested the straight in.

A couple more vectors routed me toward CRROL, the Final Approach Fix (FAF) and onto the final approach course. After passing through just a spray or two of drizzle, Runway 6 at KVKX popped into view for an uneventful landing. N631S was soon snug in the hangar and I headed home to wait for Irene.

* Or, to translate, radar vectors from Bridgeport west to the Sparta, NJ VOR then south along airway Victor 239 to the Solberg, NJ VOR thence westward along airway Victor 30 to the East Texas VOR (near Allentown, PA) thence south along airway Victor 39 to the Lancaster, PA VOR thence southeast along airway Victor 93 to the Baltimore, MD VOR, thence direct to KVKX.

Tuesday, August 23, 2011

The Mark I Eyeball (cont'd)

The previous post reviewed a flight N631S and I made about a week ago, from Potomac Airfield (KVKX) to Bridgeport (KBDR), that involved coping with some convective weather. The coping mechanisms included the XM Weather NEXRAD display, advice from ATC based on their radar displays, and the Mark I Eyeball. To continue with the theme, herewith a review of last Friday's return flight with more weather and more coping.

By the time I arrived at KBDR, a little after 20Z, it was obvious that my anticipated clearance over eastern Pennsylvania (via Sparta, Allentown, Lancaster, etc.) was a non-starter. I told Clearance Delivery that I was "unable" that routing due to extensive convective activity and asked for a route over Deer Park (DPK), thence JFK and Victor 16 over New Jersey down to the DC area. This time, New York Approach came back fairly quickly with a workable clearance: Vectors to DPK V16 ENO V268 SWANN BAL thence direct to KVKX. That was about as good as I was going to get.

I was already aware of a sizable patch of stormy weather churning around over Delaware and eastern Maryland and not moving too quickly. My working theory was that I could get started and head down there, get at least as far as southern New Jersey, and then work with ATC to work through that OR work around it OR land somewhere and wait it out. But the route across JFK and down through central NJ looked good – so we got underway just about 2030Z.

The screen capture at left, taken about 20 minutes after departure, is interesting for two reasons. First, all of that colorful stuff off to the northwest gives a good idea of why the original clearance's route was not going to work. I for one wouldn't care to fly through all that! Second, there's a little surprise waiting for me up ahead, southwest of DIXIE. Where did that come from? About forty minutes before, a last look at the radar display at the FBO had shown no weather at all in that part of New Jersey. I activated the "Animate Weather" option on the Garmin GPSmap 396 and got an answer. The weather in question had popped into existence about 25 minutes earlier and had grown explosively! Well, now I needed to deal with it.

Nearing DIXIE, New York Approach handed me off to McGuire Approach. As I checked in with McGuire I asked if a deviation left, perhaps "direct Atlantic City", was in order for weather avoidance. The controller advised that I should expect a turn to a 180 heading in a couple of miles. That surprised me, but his display's information was more current than mine. I'd happily accept the more aggressive turn.

The turn to the south came quickly, along with a descent from 6,000 feet to 4,000. This proved to be quite important because it allowed me to "stay visual" on the weather for the rest of the flight. Then, after about five miles the controller asked, "Skylane 31 Sierra, can you accept a 230 heading at this time?" Well, I figured, first, he wouldn't have asked if it didn't look acceptable to him. And the NEXRAD picture indicated that the proposed heading would keep me out of the more undesirable colors.

And, finally, looking off to the right I didn't see anything intimidating. With all inputs in favor, I turned N631S to the 230 heading. That done, my friend at McGuire Approach handed me off to Atlantic City Approach. I checked on and the ACY controller gave me an altimeter setting and added, "Deviations for weather are approved, just let me know what you're doing. And advise when you can head back toward Victor 16." I said wilco, but that it would be a while.

I kept N631S on the 230 heading, essentially paralleling Victor 16, until the NEXRAD display and the Mark I Eyeball agreed that the more enthusiastic weather was passing behind us and that a turn to the west was workable. In fact, the display showed a nice clear path back over to the Cedar Lake VOR (VCN), which is on the Victor 16 airway. I told the controller I thought direct VCN would work and got an "Approved!" from him.

That turn to VCN was the start of a quiet 15 minutes, which I used to think about my options for the next part of the flight. This was where the weather began to look really interesting. There was no obvious path on the NEXRAD display toward and beyond Dover AFB. The clear lane I was in continued west toward Wilmington but there wasn't a clear "out" at the far end. There was a path around to the east but it would be a long detour. Well, soon Atlantic City would hand me off to Dover Approach and I would discuss the situation with them.

As N631S and I crossed the New Jersey coast and headed out over Delaware Bay I was switched to Dover Approach. Checking on, I asked the controller how the weather was looking to him. He replied, "We have areas of moderate to heavy precipitation. Turn to a 240 heading."

Now that didn't look too slick on the NEXRAD display. But the controller liked it, and to the Mark I Eyeball it didn't look too bad at all (left). OK, I'm in. If it got nasty I could turn 180º and trek off to the east. But with clouds to the left and clouds to the right, I was flying toward the light, in light rain and smooth air.

The Dover controller bent my course a little further to the left and asked what my flight conditions were. I told him, and he said, "It looks like you'll go through some moderate rain...it's about the best you're going to do." There was one more patch of precip to get past, and conditions were really not too bad.

The photo at left was taken just seconds after the preceding screen shot. It shows about the worst flight conditions I saw during the entire flight. But the path toward better conditions is clearly visible and it was consistent with the controller's guidance. And in a few more minutes N631S and I flew into the clear.

From then on the hard part was over. I should note that the area of rain I worked through with the help of the Dover Approach controller (and the Mark I Eyeball) was free of any indication of lightning. I saw a couple of flashes off to the left while crossing Delaware bay, but none where I was actually headed – the presence of lightning would have required a different plan. As it was, once past those rain cells the rest of the flight across eastern Maryland and into the DC area was clear of weather. My array of tools for coping with the adverse weather appeared to have served me well.