Narrative:

Pre-flight; taxi-out; and takeoff were normal. After takeoff; when selecting flaps 0 from flaps 1; we received a slat fail EICAS caution message. We performed QRH procedure; which failed to make the message go out. After performing steps 1-2 of the procedure; we also received shaker anticipated; aoa limit fail; and spoiler fault EICAS caution messages. Slat position was visually confirmed to be partially extended; barely from the fully retracted position. We contacted dispatch and determined that a return to [departure airport] was appropriate. Take-off weight was approximately 82;000 pounds; which exceeds the maximum structural landing weight. We experienced no aircraft control problems. We briefed the flight attendants and passengers; and entered a hold to reduce our weight below maximum landing weight. We remained in contact with dispatch. As a precaution; we declared an emergency and requested emergency equipment to standby for our landing. We landed uneventfully. Maximum brake temperature observed was 380C. QRH procedure lacks clear guidance as to whether the additional EICAS caution messages we received were related to our initial problem (slat fail). We can reasonably assume that the aoa limit fail and shaker anticipated messages are related; however we were unsure of the spoiler fault message. We queried dispatch and maintenance regarding whether these were related. We specifically asked whether a slat fail would cause the spoilers to switch to direct mode (see ACARS messages). Dispatch/maintenance were unable to provide an answer (final reply stated that maintenance does not know). Note that we were airborne for nearly 2 hours during this event; which should be more than enough time to determine the answer. Therefore; it was unclear to us whether it was necessary to perform the spoiler fault procedure as well. We did have the flight attendant visually confirm that the spoilers were retracted; and assumed that the spoilers would be unavailable for landing. However; clear guidance for the slat fail procedure as to which additional EICAS message; if any; may be expected as part of the procedure (and which additional systems may become inoperable as a result). Note upon landing that the ground spoilers deployed normally. Note also that an additional landing distance multiplier is used in the event that ground spoilers were unavailable (as we assumed). Again; it is not clear whether the multiplier (1.38) used as a result of a retracted slat and multiplier (1.45) as a result of a inoperative ground spoiler system are cumulative; or something else. In addition; we experienced airframe ice accretion and the stall protect ice EICAS advisory message during descent. Again; the QRH procedure lacks clear guidance as to whether a 'stall protect ice' correction shall be applied to landing speeds. We already were adding 30 KTS to vref due to the retracted slats. Field temperature was high enough that landing with any ice accretion was not a concern. If the ice correction should be applied; it adds an additional 11 KTS to our vref unnecessarily; further increasing landing distance; and increasing braking energy required. The landing tables in the QRH do list a landing distance factor for residual ice (which we did not have). We are able to communicate without issues with dispatch; however I would expect dispatch to automatically perform certain tasks without any prompting from me. These include: 1) sending us updated current and forecast weather (it was gradually deteriorating); 2) calculating landing distance requirements for us; 3) coordinating with operations and sending us gate information; and 4) any other relevant items to assist the crew. Any communications between our flight and dispatch was initiated by us. Finally; it is 100% unacceptable in a part 121 operation to receive a response of 'we don't know' about a specific maintenance problem in an emergency situation.

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Original NASA ASRS Text

Title: An ERJ-170 flight crew received a 'SLAT FAIL' EICAS along with other caution messages; causing some procedural confusion that Maintenance was unable to resolve. They declared an emergency and returned to departure airport.

Narrative: Pre-flight; taxi-out; and takeoff were normal. After takeoff; when selecting Flaps 0 from Flaps 1; we received a SLAT FAIL EICAS caution message. We performed QRH procedure; which failed to make the message go out. After performing steps 1-2 of the procedure; we also received SHAKER ANTICIPATED; AOA LIMIT FAIL; and SPOILER FAULT EICAS caution messages. Slat position was visually confirmed to be partially extended; barely from the fully retracted position. We contacted Dispatch and determined that a return to [departure airport] was appropriate. Take-off weight was approximately 82;000 LBS; which exceeds the maximum structural landing weight. We experienced no aircraft control problems. We briefed the flight attendants and passengers; and entered a hold to reduce our weight below maximum landing weight. We remained in contact with Dispatch. As a precaution; we declared an emergency and requested emergency equipment to standby for our landing. We landed uneventfully. Maximum brake temperature observed was 380C. QRH procedure lacks clear guidance as to whether the additional EICAS caution messages we received were related to our initial problem (SLAT FAIL). We can reasonably assume that the AOA LIMIT FAIL and SHAKER ANTICIPATED messages are related; however we were unsure of the SPOILER FAULT message. We queried Dispatch and Maintenance regarding whether these were related. We specifically asked whether a SLAT FAIL would cause the spoilers to switch to direct mode (see ACARS messages). Dispatch/Maintenance were unable to provide an answer (final reply stated that Maintenance does not know). Note that we were airborne for nearly 2 hours during this event; which should be more than enough time to determine the answer. Therefore; it was unclear to us whether it was necessary to perform the SPOILER FAULT procedure as well. We did have the Flight Attendant visually confirm that the spoilers were retracted; and assumed that the spoilers would be unavailable for landing. However; clear guidance for the SLAT FAIL procedure as to which additional EICAS message; if any; may be expected as part of the procedure (and which additional systems may become inoperable as a result). Note upon landing that the ground spoilers deployed normally. Note also that an additional landing distance multiplier is used in the event that ground spoilers were unavailable (as we assumed). Again; it is not clear whether the multiplier (1.38) used as a result of a retracted slat and multiplier (1.45) as a result of a inoperative ground spoiler system are cumulative; or something else. In addition; we experienced airframe ice accretion and the STALL PROTECT ICE EICAS advisory message during descent. Again; the QRH procedure lacks clear guidance as to whether a 'STALL PROTECT ICE' correction shall be applied to landing speeds. We already were adding 30 KTS to Vref due to the retracted slats. Field temperature was high enough that landing with any ice accretion was not a concern. If the ice correction should be applied; it adds an additional 11 KTS to our Vref unnecessarily; further increasing landing distance; and increasing braking energy required. The landing tables in the QRH do list a landing distance factor for residual ice (which we did not have). We are able to communicate without issues with Dispatch; however I would expect Dispatch to automatically perform certain tasks without any prompting from me. These include: 1) sending us updated current and forecast weather (it was gradually deteriorating); 2) calculating landing distance requirements for us; 3) coordinating with Operations and sending us gate information; and 4) any other relevant items to assist the crew. Any communications between our flight and Dispatch was initiated by us. Finally; it is 100% unacceptable in a Part 121 operation to receive a response of 'We don't know' about a specific maintenance problem in an emergency situation.

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.