Comms boxes...Ozz style
Guest
Posts: n/a
Comms boxes...Ozz style
A while back I worked for a SE Asian airline which had lots of Aussies. This company had adopted many of their Ozz style SOPs. Some of these made sense, others were downright weird.
I was recently chatting to an engineer friend about my experiences there, and mentioned the practice that they had convinced the locals to adopt as SOP regarding use of the VHF comms boxes.
For those of you not familiar with the 'Ozz style' it goes like this.
Most of the world (as far as I've seen) use the VHF 1 box as the main comms box. VHF 2 is used as a secondary one for getting weather, talking to company etc etc.
But not in Ozz apparently!
Down there the technique is to use VHF 1 to transmit, and VHF 2 to receive (I kid you not).
This means you have to tune the active frequency on box 1, and select the transmit switch only on that box. Box 2 is then selected to the same frequency, but the receive switch is selected on that box only.
The net result of all these shennanigans was that every time you got a frequency change you had to retune both boxes to the new frequency before transmitting on box 1 and receiving on box 2. Pain in the a**s!
When I deigned to ask why...I was told 'how else would you know if your transmitter was working/mike stuck open/transmission crossed'.
Fair enough...if that's how they wanted it then so be it. seemed like overkill to me though.
But my (electronics) engineer friend was totally incredulous. He claims that having both boxes tuned to the same frequency was likely to damage the RX box because of swamping by the too adjacent transmitting box, and that there was every likelihood the failure rates of the boxes (especially Box 2) would be higher than normal.
So, what do you think? Any Ozzies like to comment?
I was recently chatting to an engineer friend about my experiences there, and mentioned the practice that they had convinced the locals to adopt as SOP regarding use of the VHF comms boxes.
For those of you not familiar with the 'Ozz style' it goes like this.
Most of the world (as far as I've seen) use the VHF 1 box as the main comms box. VHF 2 is used as a secondary one for getting weather, talking to company etc etc.
But not in Ozz apparently!
Down there the technique is to use VHF 1 to transmit, and VHF 2 to receive (I kid you not).
This means you have to tune the active frequency on box 1, and select the transmit switch only on that box. Box 2 is then selected to the same frequency, but the receive switch is selected on that box only.
The net result of all these shennanigans was that every time you got a frequency change you had to retune both boxes to the new frequency before transmitting on box 1 and receiving on box 2. Pain in the a**s!
When I deigned to ask why...I was told 'how else would you know if your transmitter was working/mike stuck open/transmission crossed'.
Fair enough...if that's how they wanted it then so be it. seemed like overkill to me though.
But my (electronics) engineer friend was totally incredulous. He claims that having both boxes tuned to the same frequency was likely to damage the RX box because of swamping by the too adjacent transmitting box, and that there was every likelihood the failure rates of the boxes (especially Box 2) would be higher than normal.
So, what do you think? Any Ozzies like to comment?
Guest
Posts: n/a
sounds like ILS PRM procedures at YSSY. It's a method to ensure ATC to Pilot communication, which can become critical in IMC approach conditions. It's required due to "polys" again: when they build parallel runways too close to each other. Only used inside about 10 or so miles.
Read the Jepp.
------------------
Goddamit! Burnt another one
Read the Jepp.
------------------
Goddamit! Burnt another one
Guest
Posts: n/a
CaptSensible,
The person who advocated this procedure was either :
(1) A !!!!!!!! (if he was serious); or,
(2) A bloody legend (if it is the case that he managed to keep a straight face while convincing you of such a cock and bull story).
Of course, perhaps he is ex-mil, in which case all bets are off.
I have never heard of such non-sense south of the equator.
The person who advocated this procedure was either :
(1) A !!!!!!!! (if he was serious); or,
(2) A bloody legend (if it is the case that he managed to keep a straight face while convincing you of such a cock and bull story).
Of course, perhaps he is ex-mil, in which case all bets are off.
I have never heard of such non-sense south of the equator.
Joined: Aug 1998
Aviation Qualifications: ATPL
Posts: 6,623
Likes: 847
From: Ex-pat Aussie in the UK
Current procedure in my Airline (an Australian major) is for COM1 to be used for all ATC transmissions, and COM2 to be used for Weather & company, and "parked" on 121.5Mhz at other times. Exceptions are for OCTA work (COM1 on MBZ "Aerodrome traffic" freq. and COM2 on Area) and PRM monitored approaches at Sydney, as mentioned previously.
However, when I joined six years ago, they did indeed have both COMs set to the same frequency, and the pilots crosschecking that each could recieve ATC on each COM at each frequency change. Strange but true.
However, when I joined six years ago, they did indeed have both COMs set to the same frequency, and the pilots crosschecking that each could recieve ATC on each COM at each frequency change. Strange but true.
