B-17 Pilots Manual.pdf

14. EMERGENCY OPERATIONOF RADIO EQUIPMENT.a. PORT ABLE EMERGENCY RADIO- TRANSMITTER (Type SCR-578-A).(1) GENERAL.@) A complete self-contained portable emergencytransmitter is stowed on the right rear side ofbulkhead 6, and is provided for operation anywhereaway from the airplane. It is primarily designed foruse in a small boat or life raft, but it may be placedin operation anywhere a kite can be flown or wherewater may be found.(Q) When operated, the transmitter emits anMCW signal and is pretuned to the international distressfrequency of 500 kilocycles. Automatic transmissionof a predetermined signal is provided. Anysearching party can "home" on the signal with the aidof a radio compass.(£) No receiver is provided.(2) REMOVAL FROM AIRPLANE.@) If the airplane has made an emergencylanding on water, the emergency set should be removedat the same time that the life raft is removed.The set is waterproof and will float, and it is notnecessary to take any precautions in keeping theequipment out of the water; however, be sure thatit does not float out of reach.(Q) The emergency set may be dropped fromthe airplane by use of the parachute attached. Thealtitude of the airplane when dropping the equipmentshould be between 300 and 500 feet. To drop theequipment, the following steps should be observed:1. Tie the loose end of the parachute staticline to any solid metal structure of the airplane.CAUTIONBe sure that the static line is in the clear andwill not foul.~. Throw the emergency set out through aconvenient opening in the airplane. Parachute willbe opened by the static line.CAUTIONDo not attach static line to any part of one'sclothing or body when throwing the equipmentthrough the opening.(3) OPERATION. - Complete operating instructionsare contained in one of the bags which containthe equipment. Complete instructions for the u'se ofthe transmitter are also located on the transmitteritself.Q. INTER PHONE EQUIPMENT FAILURE. - In theevent of interphone equipment failure, the audio frequencysection of the command transmitter may besubstituted for the regular interphone amplifier. Tomake this connection, the pilot should place his commandtransmitter control box channel selector switchin either channel No.3 or 4 position. Set the interphonejack-box selector switch on the "COMMAND"to place the interphone equipment in operation.NOTEWhen the command transmitter control boxchannel selector switch is set in either theNo.3 or 4 position for emergency operationof the interphone equipment, it is not possibleto establish communication with any stationor any other airplane. It is possible at alltimes to resume normal command set operationby placing the channel selector switch ofthe command transmitter control box in eitherthe No.1 or 2 position..£. SUBSTITUTION OF RADIO COMPASS RECEIV-ER FOR LOW FREQUENCY COMMAND SET RE-CEIVER. - If the low frequency receiver of the commandset fails, the radio compass receiver may besubstituted, with the pilot having direct control overthe compass receiver. To complete this emergencyhook-up, the pilot must set his interphone jack-boxselector switch in the "COMP" position and then placethe radio compass selector switch in the" ANT"position.The radio compass can then be tuned as desired.d. SUBSTITUTION OF LIAISON RECEIVER FORLOW, MEDIUM, AND/OR HIGH FREQUENCY COM-MAND RECEIVER. - In case of the failure of the low,medium, and/or high frequency receiver of the commandradio equipment, the liaison receiver may besubstituted, but the pilot will have only limited controlover it. The pilot should first call the radio operatoron the interphone system and tell him what frequencyhe desires to receive, that he is switching the interphoneselector switch to the "LIAISON" position, andfor him (the radio operator) to tune in this frequencyand maintain the setting until further advised.~. COMMAND SET TRANSMITTER FAILURE.-Incase of failure of the command set transmitter, theliaison transmitter may be substituted. The pilotshould first call the radio operator on the interphoneand have him adjust the liaison transmitter to the frequencyhe desires to use. He should then set hisinterphone selector switch to the "LIAISON" positionand operate his microphone button in the samemanner that he did when the command set was inoperation. When he is through using the liaison transmitter,the pilot should place the interphone selectorswitch in the "INTER" position and tell the radio operatorto cut the liaison transmitter off, so as to reducethe load on the electrical system.48