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.


Sarah said...

I was working flight data during this flight and remember dropping your strip off to one of the controllers who talked to you. The weather on the overhead screens looked awful and I was wondering how you made it through everything - glad it turned out to be a fairly decent flight for you!! :)

Frank Van Haste said...

Hey, Sarah, thanks for thinking of me. For once your team didn't have to do the heavy lifting - McGuire, ACY and Dover did that and they were all superb! (I think you folks enjoy a little wx; gets everyone out of the routine.)

As it happened, my timing was good. There were some growlers rumbling around the DC area that would've caused a problem an hour later.

My son's fiancee was supposed to be on a Cactus flight BTV-DCA due in at 1844 local that evening. They cancelled and she wound up on MHT-LGA-DCA a day later. So for once, the little 182 outdid the airline!

And no, I will not assume that I can do that routinely. I use all available resources, keep an 'out' in my pocket, and stay far away from electrical activity and ice.

Take care - say "Hi" to Eric from me...