Narrative:

I was on sector 46. I took a hand off on a COL4; eastbound. I didn't have a whole lot going on [in] the sector at the time; but I did have an overtake with two aircraft that I was attempting to fix and all the ride reports (mdt [moderate] turbulence) and weather information on nexrad (mdt to heavy precipitation) was making me busier than the volume. I noticed the COL4 at 114 and descending. I asked the pilot their altitude; thinking it was a bad mode C hit. The next hit was 112; the pilot then stated they were having some trouble with the weather. I never called the weather because the previous sector (42) had told them about the weather several times because it started inside 42's airspace and only went into mine just [slightly]. I was having trouble understanding the pilot; partly because they weren't answering me that much and partly because their accent was difficult to understand. I couldn't get a reported altitude from the pilot; the mode C triple xxx'ed; though in darc it showed them out of 90. I finally got a report; though I can't remember the altitude; it was close to 50 I think; and I asked the pilot if they could maintain 50 (the mia in that area is 48) and told them about an alternate landing site (it was only about 8 miles north of them). The pilot couldn't hold altitude and started for the alternate; but said there was too much rain by the airport. I told them about another airport which used to be an emergency airport; but wasn't depicted on the map (though I think it is on another selectable map layer on the keypad); as well as a private strip just southwest of the fix. The pilot asked for a vector to either of those; but I was concerned that it would put him back into the heart of the weather. I suggested to him to go to another airport; even though it was further away (about 13 miles); but because the nexrad was showing him almost out of the weather and it was clear to that airport (according to nexrad). The pilot canceled IFR (I can't remember when; but it was below 5;000). Since the pilot didn't seem to be familiar with the area; but had visual contact with the ground; I used the sectional to guide him to the interstate which runs just to the west of the intended airport. I had another aircraft at 170 do a relay for me once the pilot made it to the ground. Before he landed; he stated on frequency that there was a lot of blowing dust at the airport (he circled the airport a couple of times; whether to set up for final or not I don't know). He also told me that he said that the autopilot was trying to hold altitude; but that wind shear had put him into a 3;000 FPM dive. About 45 minutes earlier; I had a BE36 at 100; about 30 miles east of this area; who had the auto pilot kick off; went into a descent and turned about 180 degrees in the opposite direction. The pilot didn't say what caused it; I had assumed it was a mechanical problem or the pilot had kicked the autopilot off inadvertently. The pilot called on the phone to talk to the supervisor; told him the same thing about the wind shear; and had decided to set the plane down to make sure nothing had damaged the aircraft; to settle his nerves (he said he was rattled; for that matter; so was I); and to wait for the storm to clear before going on to his planned destination. Recommendation; although there wasn't anything I could really do to prevent this occurrence based on the information I had on hand; there is one thing I think we can do better as an organization to become more proactive when it comes to weather. The vast majority of the weather information we have is based on pireps and it learned retroactively. Although we have a weather information terminal at the supervisor desk; most controllers; myself included; neither can see it from the sectors nor really understand the information presented on the screen. I know the jet stream; but the other screens that cycle through are relatively gibberish to me. Also; I am assuming that wind shear or something similar was probably forecasted for the day. I also had a ton of weather (there were earlier reports of moderate rime icing) and bad rides (moderate turbulence from FL180 to FL240). I have to assume all of this stuff was forecasted; but it seems like the forecast is never discussed with the controller workforce and is always found out about retroactively; i.e. When a pilot tells us. I know the supervisors; traffic management supervisors; and operations managers go to stand up in the weather station up front and get a briefing on this; but the information is never disseminated beyond that point. Although I couldn't have prevented this; if the condition was forecasted and the information was properly disseminated; I might have been able to warn the COL4 pilot about it so it wouldn't have taken him and me by surprise. When I was in the military (approach control at three locations); we always showed up for work fifteen minutes early so we could get a crew brief on what to expect that day with respect to equipment; weather; conditions; etc. It helped prevent problems throughout the shift.

Google
 

Original NASA ASRS Text

Title: Enroute Controller detailed a significant wind shear event resulting in a General Aviation aircraft making an unscheduled landing; unable to maintain altitude; the reporter expressing concern reference the limited weather equipment/information available to controllers at the sector/s.

Narrative: I was on Sector 46. I took a hand off on a COL4; eastbound. I didn't have a whole lot going on [in] the sector at the time; but I did have an overtake with two aircraft that I was attempting to fix and all the ride reports (MDT [moderate] Turbulence) and weather information on NEXRAD (MDT to HEAVY precipitation) was making me busier than the volume. I noticed the COL4 at 114 and descending. I asked the Pilot their altitude; thinking it was a bad Mode C hit. The next hit was 112; the Pilot then stated they were having some trouble with the weather. I never called the weather because the previous Sector (42) had told them about the weather several times because it started inside 42's airspace and only went into mine just [slightly]. I was having trouble understanding the Pilot; partly because they weren't answering me that much and partly because their accent was difficult to understand. I couldn't get a reported altitude from the Pilot; the Mode C triple xxx'ed; though in DARC it showed them out of 90. I finally got a report; though I can't remember the altitude; it was close to 50 I think; and I asked the Pilot if they could maintain 50 (the MIA in that area is 48) and told them about an alternate landing site (it was only about 8 miles north of them). The pilot couldn't hold altitude and started for the alternate; but said there was too much rain by the airport. I told them about another airport which used to be an emergency airport; but wasn't depicted on the map (though I think it is on another selectable map layer on the keypad); as well as a private strip just southwest of the fix. The pilot asked for a vector to either of those; but I was concerned that it would put him back into the heart of the weather. I suggested to him to go to another airport; even though it was further away (about 13 miles); but because the NEXRAD was showing him almost out of the weather and it was clear to that airport (according to NEXRAD). The Pilot canceled IFR (I can't remember when; but it was below 5;000). Since the Pilot didn't seem to be familiar with the area; but had visual contact with the ground; I used the sectional to guide him to the Interstate which runs just to the west of the intended airport. I had another aircraft at 170 do a relay for me once the Pilot made it to the ground. Before he landed; he stated on frequency that there was a lot of blowing dust at the airport (he circled the airport a couple of times; whether to set up for final or not I don't know). He also told me that he said that the autopilot was trying to hold altitude; but that wind shear had put him into a 3;000 FPM dive. About 45 minutes earlier; I had a BE36 at 100; about 30 miles east of this area; who had the auto pilot kick off; went into a descent and turned about 180 degrees in the opposite direction. The Pilot didn't say what caused it; I had assumed it was a mechanical problem or the Pilot had kicked the autopilot off inadvertently. The Pilot called on the phone to talk to the Supervisor; told him the same thing about the wind shear; and had decided to set the plane down to make sure nothing had damaged the aircraft; to settle his nerves (he said he was rattled; for that matter; so was I); and to wait for the storm to clear before going on to his planned destination. Recommendation; although there wasn't anything I could really do to prevent this occurrence based on the information I had on hand; there is one thing I think we can do better as an organization to become more proactive when it comes to weather. The vast majority of the weather information we have is based on PIREPs and it learned retroactively. Although we have a weather information terminal at the supervisor desk; most controllers; myself included; neither can see it from the sectors nor really understand the information presented on the screen. I know the jet stream; but the other screens that cycle through are relatively gibberish to me. Also; I am assuming that wind shear or something similar was probably forecasted for the day. I also had a ton of weather (there were earlier reports of moderate rime icing) and bad rides (moderate turbulence from FL180 to FL240). I have to assume all of this stuff was forecasted; but it seems like the forecast is never discussed with the controller workforce and is always found out about retroactively; i.e. when a pilot tells us. I know the supervisors; Traffic Management Supervisors; and Operations Managers go to stand up in the weather station up front and get a briefing on this; but the information is never disseminated beyond that point. Although I couldn't have prevented this; if the condition was forecasted and the information was properly disseminated; I might have been able to warn the COL4 Pilot about it so it wouldn't have taken him and me by surprise. When I was in the military (Approach Control at three locations); we always showed up for work fifteen minutes early so we could get a crew brief on what to expect that day with respect to equipment; weather; conditions; etc. It helped prevent problems throughout the shift.

Data retrieved from NASA's ASRS site as of April 2012 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.