Transponder to standby
Guest
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Just as a point of information -- do all transponders use thumbwheel switches or one-button-per-digit? While these were common in certain classes of radio equipment a few years back, as far as I'm aware most such applications now use a keypad plus some form of execute/load button.
That has the advantage that you can't select an intermediate code while you're changing the settings, but does mean that if you don't press the execute button properly you're left thinking that the code displayed has been accepted while the equipment is still using the old one. Good user interface design (UID) can minimise the chance of this happening, through a number of strategies.
I'dve thought that in any case better UID could sort out this problem, leaving the transponder active on the old setting during the process of changing the code while ensuring the code IS changed safely, even during very busy or choppy times. In this particular case, the fact that the safety aspects are so pressing and that both modes of use -- going to standby during change, or leaving it active -- have their downsides makes me think that this is a good case for getting some kind of fix into the works.
R
That has the advantage that you can't select an intermediate code while you're changing the settings, but does mean that if you don't press the execute button properly you're left thinking that the code displayed has been accepted while the equipment is still using the old one. Good user interface design (UID) can minimise the chance of this happening, through a number of strategies.
I'dve thought that in any case better UID could sort out this problem, leaving the transponder active on the old setting during the process of changing the code while ensuring the code IS changed safely, even during very busy or choppy times. In this particular case, the fact that the safety aspects are so pressing and that both modes of use -- going to standby during change, or leaving it active -- have their downsides makes me think that this is a good case for getting some kind of fix into the works.
R
Guest
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FBW,
Thanks for a summary of your visit to the D&D chap.
Would you mind next time at the office, popping in to your supervisor and or techs and asking them what would happen if everybody in the UK FIR's switched their transponder to standby when changing squawk?
Would this suit the overall operation or not?
BTW, have a careful read of my precise words on TCAS. I didn't teach the use for a number of years to be taken for granted.
G'day
[This message has been edited by Feather #3 (edited 05 May 2000).]
Thanks for a summary of your visit to the D&D chap.
Would you mind next time at the office, popping in to your supervisor and or techs and asking them what would happen if everybody in the UK FIR's switched their transponder to standby when changing squawk?
Would this suit the overall operation or not?
BTW, have a careful read of my precise words on TCAS. I didn't teach the use for a number of years to be taken for granted.
G'day
[This message has been edited by Feather #3 (edited 05 May 2000).]
Guest
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Interesting Thread.
Hadn't considered the push-button SSR type.
Along the same vane.....
What is o/s (non-oz) view on ACFT sel TXPDR ON/ALT before entering the active RWY? And what about when crossing an Active runway during taxy out? Also...what are your company procedures for TCAS mode selection whilst in the TMA or close prox to AD?
[email protected]
www.highabove.com
[This message has been edited by LoLevel (edited 06 May 2000).]
[This message has been edited by LoLevel (edited 06 May 2000).]
Hadn't considered the push-button SSR type.
Along the same vane.....
What is o/s (non-oz) view on ACFT sel TXPDR ON/ALT before entering the active RWY? And what about when crossing an Active runway during taxy out? Also...what are your company procedures for TCAS mode selection whilst in the TMA or close prox to AD?
[email protected]
www.highabove.com [This message has been edited by LoLevel (edited 06 May 2000).]
[This message has been edited by LoLevel (edited 06 May 2000).]
Guest
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Since SSR will rarely pick up a squawk from the ground (at my place, I'm lucky if it picks it up from 500'!), I would say not necessarily b4 you enter the active, but certainly yes please definately b4 you roll. I'm also ppl/me/imc used to work for Air Service Training (remember them?) at EGPT. Last 3 chks on the runway b4 roll were txpr - alt
strobes - on
rwy - clear.
Something I always stick to.
Consider this; A/c recovering on RAS to ILS at busy class G airfield, a/c 2 gets airborne to depart 3/4 upwind vfr, but not yet switched on txpr...OOPS AVOIDING ACTION!!!
How am I the radar controller supposed to know that the primary blip is remaining at 1000' if he's not wearing the squawk I gave him?
I give squawks for a reason (not just to ease my nerves), but anyway, doesn't the Good Book say somethin about
"Txpr-equipped a/c are to squawk 7000 + mode C from t/o to t/d unless instructed to squawk a discrete code issued by an ATSU, the exeptions being a/c in emergency (natch) and a/c remaining in the visual circuit (txpr to s'by)
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Once more unto the breach, Dear Friends...
strobes - on
rwy - clear.
Something I always stick to.
Consider this; A/c recovering on RAS to ILS at busy class G airfield, a/c 2 gets airborne to depart 3/4 upwind vfr, but not yet switched on txpr...OOPS AVOIDING ACTION!!!
How am I the radar controller supposed to know that the primary blip is remaining at 1000' if he's not wearing the squawk I gave him?
I give squawks for a reason (not just to ease my nerves), but anyway, doesn't the Good Book say somethin about
"Txpr-equipped a/c are to squawk 7000 + mode C from t/o to t/d unless instructed to squawk a discrete code issued by an ATSU, the exeptions being a/c in emergency (natch) and a/c remaining in the visual circuit (txpr to s'by)
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Once more unto the breach, Dear Friends...
Guest
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Interesting question, "Turn x-ponder to standby when changing codes"? Back to the books. Our King Air is equipped with dual Collins TDR-94 mode-S units. Upon any change to the code selection, the control head waits approx 5 seconds before resuming squawk. I have to believe that most units today have this feature.-CY
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*deep inhale* I LOVE the smell of jet-a in the morning..
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*deep inhale* I LOVE the smell of jet-a in the morning..
Guest
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From an ATC's point of view, pilots SHOULD select transponder to standby prior to changing the assigned code!
The reason is that in the process of changing the code, the radar may sweep and pick up an intermediate code which has been assigned to another aircraft. Alternatively a wrong code could be selected, and be transmitted prior to the error being realised by the pilot. This could cause an erroneous code/callsign coupling. This is particularly a problem with the newer ATS systems which display flight plan, ADS and radar tracks, as a pilot squawking the wrong code can cause the deletion of the aircraft symbol of a lower hierarchy (eg: a flight plan track).
Of course, transponders and radar systems do have features to mitigate these risks, but they don't seem to work...
The reason is that in the process of changing the code, the radar may sweep and pick up an intermediate code which has been assigned to another aircraft. Alternatively a wrong code could be selected, and be transmitted prior to the error being realised by the pilot. This could cause an erroneous code/callsign coupling. This is particularly a problem with the newer ATS systems which display flight plan, ADS and radar tracks, as a pilot squawking the wrong code can cause the deletion of the aircraft symbol of a lower hierarchy (eg: a flight plan track).
Of course, transponders and radar systems do have features to mitigate these risks, but they don't seem to work...
Guest
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Here it is verbatim...The Ctl head waits approx. 5 sec. before sending the new code to the transponder. This provides time for verification of the selected code before it is transmitted and prevents inadvertant transmission of a partially set code. For 7700 & 7600, the display (Ctl Head) flashes the code for 5 sec. before sending the code to the transponder.--CY
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*deep inhale* I LOVE the smell of jet-a in the morning..
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*deep inhale* I LOVE the smell of jet-a in the morning..
Guest
Posts: n/a
"just when you thought it was safe to come out..................................!"
Airservices Australia have just issued a Notam shooting down my previous argument [which was based on Euro/US data.]
They have decided that transponders should be selected to SBY prior to squawk change if you have a 'tumbler' selection unit as you may trigger someone else's code and confuse the system.
Life wasn't meant to be easy!!
G'day
Airservices Australia have just issued a Notam shooting down my previous argument [which was based on Euro/US data.]
They have decided that transponders should be selected to SBY prior to squawk change if you have a 'tumbler' selection unit as you may trigger someone else's code and confuse the system.
Life wasn't meant to be easy!!
G'day
Guest
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<font face="Verdana, Arial, Helvetica" size="2">I have to say that I thought it was all a bit much ado about nothing until my 170a flight test for my instrument rating. I was changing xpndr codes (on standby ).
I glanced down to check the code before I switched the thing on and blow me if I didn't find the thing reading 7700 and an examiner waiting expectantly...</font>
I glanced down to check the code before I switched the thing on and blow me if I didn't find the thing reading 7700 and an examiner waiting expectantly...</font>
-me
Guest
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The initial question seemed to be whether good airmanship dictated that turning the transponder to standby would prevent wrong squawks showing on radar. That seems sensible, especially when you think (as many of you don't seem to be) that we are talking about student pilots with twiddly knob transponders and an information overload. It is not as simple as you airliner types with two transponders and push buttons. It seems a good starting point from which you can progress when you start moving to push button or two transponders etc.
From an ATC point of view we have a system called Auto-DM which recognises the squawk assigned to a flight in the computer. Within certain parameters, if the computer sees that squawk it will activate the flight. If you have by chance selected the squawk in error then the computer will produce flight strips, estimates etc for a flight which is not yet airborne. The plan will then need to be cancelled and re-input. OK so the chances are small, but we are in the business of minimising chances of error, so if you can do that by selecting standby then what's stopping you?
I will certainly continue to teach my students to squawk standby, especially as some of them take 30 seconds or more to finish twiddling the buttons!
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"Take-off is optional, Landing is mandatory"
From an ATC point of view we have a system called Auto-DM which recognises the squawk assigned to a flight in the computer. Within certain parameters, if the computer sees that squawk it will activate the flight. If you have by chance selected the squawk in error then the computer will produce flight strips, estimates etc for a flight which is not yet airborne. The plan will then need to be cancelled and re-input. OK so the chances are small, but we are in the business of minimising chances of error, so if you can do that by selecting standby then what's stopping you?
I will certainly continue to teach my students to squawk standby, especially as some of them take 30 seconds or more to finish twiddling the buttons!
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"Take-off is optional, Landing is mandatory"
Guest
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Single engine, single crew, IMC, no autopilot
my technique (as taught by a great instructor)is stanby-scan-twiddle-scan-twiddle-scan-check-scan-squawk and txpndr only goes on during after take off checks to avoid unnecessary garbling in the circuit area. Probably very different in Class A and a Jumbo but that's my twopenneth. ATCOing at a non SSR unit, with lots of puddle jumpers we get lots of calls from D&D about misdialled 7700's
my technique (as taught by a great instructor)is stanby-scan-twiddle-scan-twiddle-scan-check-scan-squawk and txpndr only goes on during after take off checks to avoid unnecessary garbling in the circuit area. Probably very different in Class A and a Jumbo but that's my twopenneth. ATCOing at a non SSR unit, with lots of puddle jumpers we get lots of calls from D&D about misdialled 7700's
Guest
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Whose idea was 7000 for conspicuity?
Only one click away from SOS.
What's wrong with 1200?
How many times have you dialled up your slot time in your transponder and forgot to change it? Why do you do that? Don't you have a pen?
As eyeinthesky said, false autoDM on an incorrect squawk is very common. I reckon I have to get a pilot to change squawk after departure at least once an hour!
To standby or not standby, I don't mind.
Just set it right!
Only one click away from SOS.
What's wrong with 1200?
How many times have you dialled up your slot time in your transponder and forgot to change it? Why do you do that? Don't you have a pen?
As eyeinthesky said, false autoDM on an incorrect squawk is very common. I reckon I have to get a pilot to change squawk after departure at least once an hour!
To standby or not standby, I don't mind.
Just set it right!
Guest
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I agree - I think 7000 for conspicuity was a very silly idea.
Our aircrafts' TXPDRs (Collins) are the same as Corporate Yank's - they switch themselves to standby when you twiddle until five seconds after the last input.
I appreciate the controllers' points of view regarding problems over briefly selecting a code that might trigger a flight plan, but for TCAS point of view, however long it takes (within reason) I would prefer to have my TXPDR interrogating another's.
Okay, the first might well be thoroughly inconvenient. The second might be thoroughly dangerous! And let's face it, whilst we're trying to avoid errors, we're also trying FIRST AND FOREMOST to eliminate danger.
So let's have those transponders on (please?)
As a sideline, I would also prefer use of a transponder Mode C mandatory. So often controllers pass us "Slow-moving traffic your twelve o'clock, no height information". If we're under a RAS and can't see it, he HAS to give us avoiding action, even though the chances are it's more than 10,000 below.
So instructors, please teach your studes to use Mode C at all times.
Our aircrafts' TXPDRs (Collins) are the same as Corporate Yank's - they switch themselves to standby when you twiddle until five seconds after the last input.
I appreciate the controllers' points of view regarding problems over briefly selecting a code that might trigger a flight plan, but for TCAS point of view, however long it takes (within reason) I would prefer to have my TXPDR interrogating another's.
Okay, the first might well be thoroughly inconvenient. The second might be thoroughly dangerous! And let's face it, whilst we're trying to avoid errors, we're also trying FIRST AND FOREMOST to eliminate danger.
So let's have those transponders on (please?)
As a sideline, I would also prefer use of a transponder Mode C mandatory. So often controllers pass us "Slow-moving traffic your twelve o'clock, no height information". If we're under a RAS and can't see it, he HAS to give us avoiding action, even though the chances are it's more than 10,000 below.
So instructors, please teach your studes to use Mode C at all times.
