2011-12 · NASA ASRS report 986201
B757 flight crew experiences a LE Slat disagree EICAS message during approach. The crew is confused by the new QRH procedures which do not seem to lead to using alternate slat and flap selectors; and plan a flaps up approach. During the approach the First Officer suggests using the alternate flap selector and flaps twenty are eventually achieved for landing.
Approach cleared us to slow to 210 KTS then descend to 6;000 on downwind for runway 28. I was pilot flying and as we slowed to 230 KTS; I called for flaps 1. The Captain selected flaps 1 and the flaps started to move but then stopped indicating between zero and flaps 1 position followed by a 'LE SLAT DISAGREE' EICAS and 'LEADING EDGE' light. I took the radios and continued to fly while the Captain ran the QRH. Captain ran all the steps in the QRH but was unable to get the flaps or slats to move. We were given a descent to 4;000 FT and encountered moderate rime ice at that altitude (we had the wing and engine anti-ice on prior to this encounter as we had received previous reports from ATC). We were then given a base leg and cleared to descend to 3;000 FT which got us out of the icing conditions. The Captain declared an emergency and advised ATC of our situation. The Captain then took the airplane and I reverted to pilot not flying duties. We discussed the approach speed we would need for what appeared to be a flaps up landing. The Captain was frustrated by the QRH and asked me to review the steps again to see if he had missed anything (we were still quite a ways out from touchdown so I had time). I ran the QRH steps again and had the same results he got with the flaps seemingly stuck between zero and one. With Tower calling the winds 340/15G28; the Captain wisely elected to go around and had me ask for vectors to 32L. During the downwind portion of our vectoring; I asked the Captain if I could try selecting the flaps to '5' with the alternate extend switch. I don't know why but the flaps did move this time and I asked him to slow to 170 KTS to see if I could get the flaps out further. We were able to get to flaps 20 with the alternate flap switch but the slats never did come out (this was confirmed with a deadheading pilot on the ground after we landed). The Captain asked me to take the airplane and the radios again; as he wanted to brief the passengers on what was going on. I continued flying the vectors from ATC for a visual approach to 32R without aide of an ILS or PAPI. We elected to use Vref 30 + 30 KTS as the target speed and I flew a successful approach and landing to 32R without further incident. I debriefed Maintenance on our situation and they told me this airplane had a history of flap/slat selector valve problems. The Captain and I talked about what we did and tried to determine if there was anything we would have done differently and came to the following conclusions: 1.) The training we received on use of the QRH was totally inadequate to prepare us for this emergency. Instead of being a useful tool to help us properly configure the airplane for the malfunction; we were forced to rely mostly on our prior training and experience to get us and our passengers safely down. 2.) The QRH directs us to go from the 'LEADING EDGE SLAT DISAGREE' checklist (which is what we had) to the 'LEADING EDGE SLAT ASYMMETRY' checklist (Which is NOT what we were dealing with and didn't make sense to either of us) to determine what speeds to fly. In my opinion; the 'LEADING EDGE SLAT DISAGREE' checklist SHOULD have taken us all the way through configuring the airplane AND the appropriate speeds the way our old flight manual checklists did. 3.) I warned in a previous report that the training approach the Company adopted was inadequate and that it was (IS) reckless to have crews learning to use new checklists/procedures in the form of OJT with passengers on board and here is a case-in-point. We were in an EXTREMELY BUSY AND HAZARDOUS ENVIRONMENT having to deal with a NON-NORMAL situation with an UNFAMILIAR CHECKLIST TOOL with peoples lives at stake. Fortunately and in spite of the incomplete training we received; the outcome was successful and nobody got hurt. However; I believe were it not for our previous experience and skill; the outcome may have been different.
First Officer called for flaps 1 as we slowed for the approach. Trailing edge flaps stopped between position up and 1. EICAS message L.E. Flaps Disagree. Ran appropriate check list; very frustrating. First Officer ran checklist also and we both came to the same conclusion. Flaps up landing [we] declared emergency with approach. [We] advised flight attendants. As we approached the first runway we elected a missed approach. [We] requested another runway to land directly into wind. While being vectored around I decided that since we did not have an EICAS message regarding the trailing edge flaps I would try the alternate system to extend them. We managed to get flaps 20. [We] made uneventful landing on the second runway.
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Source: NASA Aviation Safety Reporting System (public domain). Reports are voluntary submissions and are not verified by NASA.
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