This latest “interactive” issue of CALLBACK deals with two situations that involve general aviation pilots and one that involves an air carrier flight crew. In “the first half of the story” you will find report excerpts describing the situation up to the decision point. It is up to the reader to determine the possible courses of action and make a decision (preferably within the same time frame that was available to the reporter). The selected ASRS reports may not give all the information you want and you may not be experienced in the type of aircraft involved, but each incident should give you a chance to exercise your aviation decision-making skills. In “the rest of the story,” you will find the actions actually taken by reporters in response to each situation. Bear in mind that their decisions may not necessarily represent the best course of action. Our intent is to stimulate thought, discussion, and training related to the type of incidents that were reported. The First Half of the Story Situation # 1: (C170 Pilot's Report) ■ We diverted east-northeast…due to a slow moving storm system across the direct route to my destination…. We were getting beat up with turbulence and I climbed above a scattered layer into smooth air, climbing to 6,500 feet MSL. The layer gradually increased in altitude and I climbed to 8,500 feet MSL to maintain VFR cloud clearances. Everything was fine at this point, but the cloud layer gradually increased to a continuous layer. The cloud layer was expected, but I also expected to be well past it before having to descend for fuel. I stayed above the layer rather than backtracking and descending below the layer. This was a poor decision. The wind gradually increased to about 40 knots of headwind. It gradually became clear to me that I did not have adequate fuel to get past the layer. The cloud layer did turn out to disappear approximately where I expected it to, but I could not get there with the fuel on board. I was way too far into the corner I created by the time I admitted it to myself. At this point, I did not believe backtracking was a reasonable option. The storm system, which I had done an end-run around, was slowly moving toward the route I had flown, the terrain behind me was higher, and the ceiling under the cloud layer was minimal. AWOS stations ahead of me were reporting a ceiling of greater than 6,000 feet, and some of them were reporting a broken layer. I was still hoping that I would find a break in the cloud layer and be able to stay legal VFR. I finally realized that I had to choose between two poor options: 1. A high probability of running out of fuel in flight if I continued trying to fly past the cloud layer. 2. Descend through the cloud layer, even though I am only VFR rated. Situation #2: (C172 Pilot's Report) ■ I am a member of a club which gives me access to four C172’s. I typically fly one of the160HP models. On this trip, however, I would be carrying four adults and the airplane I took on that day was a 180HP model. It was the only plane with enough useful load to carry all of us. So, I chose to fly an airplane that I had never flown before. I got some performance information from the club’s website (50 gallon, long-range tanks, 8.7 gallons/hour fuel burn, and a cruise speed of 128 knots). I used those numbers to calculate that I could fly for 5 hours and 15 minutes before reaching my 30-minute reserve. I purchased [flight planning software] earlier in the week and used that to calculate that the trip should take just under 4 hours so I thought I had plenty of fuel. Once the flight was under way, I learned that the cruise speed was more like 120 knots (at 2,400 RPM), the headwind was stronger than I had planned for and I was only achieving a ground speed of around 100 knots. However, my GPS told me that I would still be able to make [my destination] in less than 5 hours. I failed to note our exact time of departure. Situation #3: (B737 First Officer's Report) ■ It started when we were on [a published arrival] and told to hold. Dispatch gave us an alternate with an enroute fuel burn of 2,800 lbs. We were currently around 7,700 lbs. so we should have diverted then. We told ATC we wanted to divert but then they said to wait three minutes. We waited and then received clearance and vectors for the approach. Once on approach, at 6,500 lbs. on the fuel, at about 1,000 feet, we got a windshear warning and we executed a go-around. At this point, we had 5,900 lbs. of fuel. We were getting backed into a corner. We didn’t have enough fuel for the alternate and the weather was not getting any better at the [destination] airport. We told the Controller we wanted vectors for [a nearby Air Force Base] and we were approved. Everything was fine. Then ATC said the Base was closed. Approach vectored us back around for the approach. We were coming in for a flaps 30 landing. Once again at about 1,000 feet, we received a “Windshear, Go Around” command from the aircraft. | CALLBACK Issue 385 ASRS Online Resources December 2011 Report Intake: | Air Carrier/Air Taxi Pilots | 2,835 | General Aviation Pilots | 748 | Controllers | 540 | Cabin | 238 | Mechanics | 146 | Dispatcher | 68 | Military/Other | 15 | TOTAL | 4,590 | ASRS Alerts Issued: | Subject | No. of Alerts | Aircraft or aircraft equipment | 9 | Airport facility or procedure | 4 | ATC equipment or procedure | 2 | TOTAL | 15 | Special Studies In cooperation with the FAA, ASRS is conducting an ongoing study on wake vortex incidents, enroute and terminal, that occurred within the United States. Learn more » ASRS, in cooperation with the FAA, is gathering reports of incidents that occurred while pilots were utilizing weather or AIS information in the cockpit obtained via data link on the ground or in the air. Learn more » |
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