What are you talking about feather#3.....
Jurasic radar? old technique? You've obviously spent too much time in that glass cockpit that you fly.....try a bit of real flying in the real world. Oh, by the way, next time you are sitting at the controls of your 747, in between cups of coffee I would respectfully suggest you brush up on TCAS operations....which ONLY works on mode C interrogation.
Back to the real world.
I spoke to D&D at LATCC this morning who were pleased this subject has been mentioned as pilots who change squawk without going to standby mode are the bane of their lives. The chaps there were very helpfull and made three important points.
1. D&D (SAR) radar is no different from any other radar. Two hits will be required for capture.
2. ALLWAYS turn to standby when changing codes to avoid setting SAR alarms off, which happens on a regular basis due to pilots using the "Ausie" method of just changing the numbers.
3. When the SAR alarm is set off, that screen is then out of action untill the matter has been resolved thus creating a small delay should a real emergency code be transmitted.
They also mentioned that since 7000 was introduced they get far more erroneous alarms as two aircraft changing to 7000 without going to standby in close proximity can trigger the alarm. Apparantly this is quite common around the Solent area.
They informed me that there is talk of reverting back to the old 4321 conspicuity code.
It may be helpfull to draw a line between GA traffic pottering about VFR and airways traffic who will not be squawking 7000. It is the GA traffic that can cause a problem when changing without reverting to standby.
D&D are now aware of this site and may well talk to us in more detail if requested.
[This message has been edited by Flybywyre (edited 05 May 2000).]