Page:CAB Accident Report, Southeast Airlines Flight 308.pdf/8

- 8 - The closest frequency of any local facility to this setting is the Emmett "H" radio beacon which is 320 kcs. It is extremely doubtful that this receiver would be utilised on Emmett "H," however, as this homer is nondirectional. Normally the low frequency receiver is tuned to the TRI low frequency radio range, 221 kcs., and used as another aid in determining the aircraft position in relation to the radio range legs. It is clear this receiver was not being used on the TRI-LFR because it is extremely improbable that impact forces could move the frequency over 100 kcs.

Third, the ADF was tuned to the radio range frequency of 221 kcs. While en route from Knoxville to Tri-City it would be expected that the radio compass would be used to follow the airway. However, after the aircraft had reached the vicinity of the airport and an approach on the ILS was started, the crew would normally tune the ADF to the nondirectional compass locator associated with the middle or outer marker. These frequencies are: 201 kcs. and 239 kcs., respectively.

Another alternative would be to tune the ADF to the Emmett "H" facility for assistance in establishing the safe easternmost limit of the procedure turn area.

Two inferences arise because the radio compass was not tuned to the frequency of a facility which would assist in determining position along the localizer. The first is that the automatic direction finding feature was not functioning or was not being used. The second is that the radio compass was entirely inoperative and neither the visual presentation nor the audio signals could be received.

During the last transmission from the flight, the pilot stated that "... his AIF was acting up." In addition, Captain Bond testified that he was unable to receive either visual or aural signals on the ADF prior to landing at Nashville. The evidence also indicates that he informed Captain Gollmier of the malfunction at Nashville but that no maintenance was performed there or at Knoxville. It is therefore reasonable to presume that the ADF was completely inoperative and further that the crew was aware of the situation prior to take off from Nashville.

It should be noted here that there is a remote possibility that a sightseer at the crash site could have altered the setting found on the No. 2 navigation receiver frequency selector; it is also possible that the frequency selector was moved as a result of heavy inertia forces. If this were true and the receiver was being used on the TRI VOR, the pilot should have been acutely aware of his position. As for the ADF, because of the fire markings on the dial and exposed gears, investigators determined that the frequency setting had not been altered. It is clear that this receiver was tuned to 221 kcs.

Flight 308 reported as being over Gray intersection at 2024. About 2032, the conversation with the tower took place. Before completion of that conversation the aircraft crashed. This would place the accident, as near as can be determined, at 2032. A study was made to determine the airspeed which would have been required for the aircraft to traverse the distance from Gray to the crash site in eight minutes. Knowing the straight-line distance from the crash site to Gray, and the wind, and assuming a standard procedure turn and standard