MartySantic
Well Known Member
Part 91.207.d states what is required every 12 months with respect to ELT testing. My DAR inspection is scheduled for next Wed and want to make the proper logbook entry in the avionics log.
(d) Each emergency locator transmitter required by paragraph (a) of this section must be inspected within 12 calendar months after the last inspection for--
(1) Proper installation;
(2) Battery corrosion;
(3) Operation of the controls and crash sensor; and
(4) The presence of a sufficient signal radiated from its antenna.
From an article on the web, http://www.aviationtoday.com/am/categories/bga/Avionics_188.html
"There are two ways to test for sufficient antenna signal on a C91a ELT. One is to evaluate the signal strength using a test box like those made by QCAvionix or Whiffletree. The other method is to listen to the signal using an AM-band radio receiver.
The FAA endorses the AM radio test and has codified this check in the most recent update of Advisory Circular 43.13-1B (CHG 1). The test for sufficient signal radiated from the antenna is as follows (Par 12-22):
"Active the ELT using the ON or ELT TEST switch. A low-quality AM broadcast radio receiver should be used to determine if energy is being transmitted from the antenna. When the antenna of the AM broadcast receiver (tuning dial on any setting) is held about 6 inches from the activated ELT antenna, the ELT aural tone will be heard."
"It has to be a cheap AM radio," said Bob Glorioso, president of QCAvionix. "It can't be too well shielded. You're trying to overwhelm the AM detector."
Many mechanics, perhaps unaware of the FAA's recommendations, listen the ELT signal on the aircraft's VHF radio, set to receive on 121.5 megahertz. But this isn't a good test, because the aircraft radio's receiver is extremely sensitive. The AM radio test, says AC43.13, "is not a measured check; but it does provide confidence that the antenna is radiating with sufficient power to aid search and rescue. The signal may be weak even if it is picked up by an aircraft VHF receiver located at a considerable distance from the radiating ELT. Therefore, this check [VHF radio] does not check the integrity of the ELT system or provide the same level of confidence as does the AM radio check."
What the FAA is saying is that simply listening to the ELT signal on the aircraft's VHF radio does not meet the requirements of 91.207(d). "
So TWO questions.....How do I satisfy d.(4) The presence of a sufficient signal radiated from its antenna (on both 121.5 and 406 mhz) AND how do I make the proper logbook entry? Do I have to test each freq individually or is the AM radio test sufficient?
Also the battery says it is good thru July 2015. Does that mean the battery does not have to be replaced till then, provided its accumulated time does not exceed the time limit?
(d) Each emergency locator transmitter required by paragraph (a) of this section must be inspected within 12 calendar months after the last inspection for--
(1) Proper installation;
(2) Battery corrosion;
(3) Operation of the controls and crash sensor; and
(4) The presence of a sufficient signal radiated from its antenna.
From an article on the web, http://www.aviationtoday.com/am/categories/bga/Avionics_188.html
"There are two ways to test for sufficient antenna signal on a C91a ELT. One is to evaluate the signal strength using a test box like those made by QCAvionix or Whiffletree. The other method is to listen to the signal using an AM-band radio receiver.
The FAA endorses the AM radio test and has codified this check in the most recent update of Advisory Circular 43.13-1B (CHG 1). The test for sufficient signal radiated from the antenna is as follows (Par 12-22):
"Active the ELT using the ON or ELT TEST switch. A low-quality AM broadcast radio receiver should be used to determine if energy is being transmitted from the antenna. When the antenna of the AM broadcast receiver (tuning dial on any setting) is held about 6 inches from the activated ELT antenna, the ELT aural tone will be heard."
"It has to be a cheap AM radio," said Bob Glorioso, president of QCAvionix. "It can't be too well shielded. You're trying to overwhelm the AM detector."
Many mechanics, perhaps unaware of the FAA's recommendations, listen the ELT signal on the aircraft's VHF radio, set to receive on 121.5 megahertz. But this isn't a good test, because the aircraft radio's receiver is extremely sensitive. The AM radio test, says AC43.13, "is not a measured check; but it does provide confidence that the antenna is radiating with sufficient power to aid search and rescue. The signal may be weak even if it is picked up by an aircraft VHF receiver located at a considerable distance from the radiating ELT. Therefore, this check [VHF radio] does not check the integrity of the ELT system or provide the same level of confidence as does the AM radio check."
What the FAA is saying is that simply listening to the ELT signal on the aircraft's VHF radio does not meet the requirements of 91.207(d). "
So TWO questions.....How do I satisfy d.(4) The presence of a sufficient signal radiated from its antenna (on both 121.5 and 406 mhz) AND how do I make the proper logbook entry? Do I have to test each freq individually or is the AM radio test sufficient?
Also the battery says it is good thru July 2015. Does that mean the battery does not have to be replaced till then, provided its accumulated time does not exceed the time limit?
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