Beschrijving:The Merlin cargo plane was transporting 127 packages from Seattle to Spokane. The aircraft was dispatched with the primary (NAV 1) ILS receiver having been deferred (out of service) due to unreliable performance the evening before the accident, thus leaving the aircraft with the secondary (NAV 2) ILS receiver for ILS use. Approaching Spokane, the pilot was cleared for an ILS/DME runway 21R approach. Weather at the destination airport was poor with a 400 foot overcast. The pilot was given a low altitude alert by the tower and acknowledged, reporting that he was descending through 2,800 feet. At that point the aircraft was well below the ILS glideslope and about 13 seconds from impacting the trees. The pilot was given a low altitude alert by the tower and acknowledged, reporting that he was descending through 2,800 feet, which was confirmed on the mode C radar readout. At that point the aircraft was well below the ILS glideslope and about 13 seconds from impacting the trees.
|Datum:||Thursday 5 December 2013|
Swearingen SA227-AT Merlin IVC
|Motoren:|| 2 Garrett TPE331-11U-611G|
|Bemanning:||slachtoffers: 1 / inzittenden: 1|
|Passagiers:||slachtoffers: 0 / inzittenden: 0|
|Totaal:||slachtoffers: 1 / inzittenden: 1 |
|Gevolgen:|| Written off (damaged beyond repair)|
|Plaats:||5,5 km (3.4 mijl) E of Spokane-Felts Field, WA (SFF) (Verenigde Staten)
|Fase:|| Nadering (APR)|
|Vliegveld van vertrek:||Seattle-Boeing Field International Airport, WA (BFI/KBFI), Verenigde Staten|
|Vliegveld van aankomst:||Spokane-Felts Field, WA (SFF/KSFF), Verenigde Staten|
PROBABLE CAUSE: "The pilot-in-command's failure to maintain proper glidepath alignment during an ILS approach in poor weather resulting in collision with trees and terrain. Contributing factors were the unreliable status of the primary (NAV 1) ILS receiver (leaving the pilot with only the secondary (NAV 2) ILS receiver), the low ceilings and trees."
Deze kaart geeft het vliegveld van vetrek weer en de geplande bestemming van de vlucht. De lijn tussen de vliegvelden geeft niet
de exacte vliegroute weer.
De afstand tussen Seattle-Boeing Field International Airport, WA en Spokane-Felts Field, WA bedraagt 371 km (232 miles).
This information is not presented as the Flight Safety Foundation or the Aviation Safety Networkĺs opinion as to the cause of the accident. It is preliminary and is based on the facts as they are known at this time.